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دانلود کتاب Rosen's Emergency Medicine: Concepts and Clinical Practice: 2-Volume Set
دانلود کتاب اورژانس روزن: مفاهیم و عملکرد بالینی: مجموعه 2 جلدی
مشخصات کتاب
Rosen's Emergency Medicine: Concepts and Clinical Practice: 2-Volume Set
ویرایش: [10 ed.] نویسندگان: Ron Walls, Robert Hockberger, Marianne Gausche-Hill, Timothy Erickson, Susan Wilcox سری: ISBN (شابک) : 0323757898, 9780323758482 ناشر: Elsevier سال نشر: 2022 تعداد صفحات: [3050] زبان: English فرمت فایل : PDF (درصورت درخواست کاربر به PDF، EPUB یا AZW3 تبدیل می شود) حجم فایل: 280 Mb
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توجه داشته باشید کتاب اورژانس روزن: مفاهیم و عملکرد بالینی: مجموعه 2 جلدی نسخه زبان اصلی می باشد و کتاب ترجمه شده به فارسی نمی باشد. وبسایت اینترنشنال لایبرری ارائه دهنده کتاب های زبان اصلی می باشد و هیچ گونه کتاب ترجمه شده یا نوشته شده به فارسی را ارائه نمی دهد.
توضیحاتی در مورد کتاب اورژانس روزن: مفاهیم و عملکرد بالینی: مجموعه 2 جلدی
برای نزدیک به 40 سال، اورژانس روزن، پزشکان اورژانس، دستیاران، دستیاران پزشک و سایر پزشکان اورژانس را با اطلاعات معتبر، در دسترس و جامع در این زمینه به سرعت در حال تحول در اختیار آنها قرار داده است. نسخه دهم کاملاً بازبینی شده دانش عملی، مبتنی بر شواهد و توصیه‌های خاص از متخصصان بالینی را در قالبی واضح و دقیق، با نوشتار متمرکز، مراجع فعلی و استفاده گسترده از تصاویر برای ارائه راهنمایی قطعی برای شرایط اضطراری ارائه می‌کند. با پوششی از مدیریت راه هوایی و مراقبت های ویژه تا تشخیص و درمان تقریباً هر وضعیت اورژانسی، از بسیار پیچیده گرفته تا ساده و رایج، این مرجع دو جلدی برنده جایزه، انتخاب شماره 1 شما برای اطلاعات معتبر و به روز است. در سراسر طیف عمل پزشکی اورژانس. فوراً مرتبط‌ترین محتوای بالینی را از هر منبع پزشکی اورژانسی ارائه می‌کند و توصیه‌های تشخیصی و درمانی و گردش کار را با نشانه‌های واضح و اقدامات ترجیحی ارائه می‌دهد. شامل هشت فصل کاملاً جدید است که ویروس‌های کرونا/COVID-19، بیمار چاق مرضی، قاچاق انسان، بیماران اقلیت جنسی (LGBTQ)، عوامل اجتماعی تعیین‌کننده سلامت، خشونت جامعه، و کمک‌های بشردوستانه در جنگ و بحران را پوشش می‌دهد. دارای بیش از 1700 شکل، از جمله بیش از 350 طرح جدید آناتومی، نمودارها و نمودارها، الگوریتم‌ها و عکس‌ها. شامل اطلاعات جدید در سراسر طیف مراقبت های اورژانسی، مانند مدیریت راه های هوایی بزرگسالان و کودکان، شوک، بیماری همه گیر، سم شناسی اورژانسی، سندرم سپسیس، احیا، فوریت های پزشکی بارداری، بیمار دچار نقص ایمنی، کودک آزاری، آرامبخشی کودکان، ترومای کودکان، و بیشتر. دارای الگوهای فصل اصلاح شده و اصلاح شده است که ناوبری را بهبود می بخشد و یافتن سریع اطلاعات کلیدی را آسان می کند. دسترسی به بیش از 1200 پرسش و پاسخ آنلاین برای کمک به آمادگی برای امتحان، و همچنین دوجین کلیپ ویدیویی جدید را فراهم می‌کند که نشان می‌دهد چگونه می‌توان روش‌های اضطراری بحرانی را به بهترین شکل در زمان واقعی انجام داد. بررسی و تایید پوشش به جلد توسط تیمی از داروسازان بالینی خبره برای اطمینان از صحت و کامل بودن تمام اطلاعات دارویی و توصیه‌های درمانی. نسخه کتاب الکترونیکی پیشرفته همراه با خرید. کتاب الکترونیکی پیشرفته شما به شما امکان می دهد به تمام متن ها، شکل ها و مراجع کتاب در دستگاه های مختلف دسترسی داشته باشید.
توضیحاتی درمورد کتاب به خارجی
For nearly 40 years, Rosen’s Emergency Medicine has provided emergency physicians, residents, physician assistants, and other emergency medicine practitioners with authoritative, accessible, and comprehensive information in this rapidly evolving field. The fully revised 10th Edition delivers practical, evidence-based knowledge and specific recommendations from clinical experts in a clear, precise format, with focused writing, current references, and extensive use of illustrations to provide definitive guidance for emergency conditions. With coverage ranging from airway management and critical care through diagnosis and treatment of virtually every emergency condition, from highly complex to simple and common, this award-winning, two-volume reference remains your #1 choice for reliable, up-to-date information across the entire spectrum of emergency medicine practice. Offers the most immediately clinically relevant content of any emergency medicine resource, providing diagnostic and treatment recommendations and workflows with clear indications and preferred actions. Contains eight entirely new chapters covering coronaviruses/COVID-19, the morbidly obese patient, human trafficking, sexual minority (LGBTQ) patients, social determinants of health, community violence, and humanitarian aid in war and crisis. Features over 1,700 figures, including more than 350 new anatomy drawings, graphs and charts, algorithms, and photos. Includes new information across the spectrum of emergency care, such as adult and pediatric airway management, shock, pandemic disease, emergency toxicology, sepsis syndrome, resuscitation, medical emergencies of pregnancy, the immunocompromised patient, child abuse, pediatric sedation, pediatric trauma, and more. Features revised and refined chapter templates that enhance navigation, making it easy to find key information quickly. Provides access to more than 1,200 questions and answers online to aid in exam preparation, as well as two dozen new video clips showing how to best perform critical emergency procedures in real time. Reviewed and verified cover-to-cover by a team of expert clinical pharmacists to ensure accuracy and completeness of all drug information and treatment recommendations. Enhanced eBook version included with purchase. Your enhanced eBook allows you to access all of the text, figures, and references from the book on a variety of devices.
فهرست مطالب
Cover ROSEN’S Emergency Medicine Concepts and Clinical Practice Copyright Acknowledgments Contributors Preface to the Tenth Edition Preface to the Ninth Edition How This Medical Textbook Should Be Viewed by the Practicing Clinician and Judicial System 1 - Airway Principles Background Anatomy, Physiology, and Pathophysiology Failure to Maintain or Protect the Airway Failure of Ventilation or Oxygenation Anticipated Clinical Course Identification of the Difficult Airway Difficult Direct Laryngoscopy: LEMON . The patient first should be examined for external markers of difficult intubation, which are determined based simply on the in... . The second step in the evaluation of the difficult airway is to assess the patient’s airway geometry to determine suitability ... . Oral access is assessed with the Mallampati scale (Fig. 1.3). Visibility of the oral pharynx ranges from complete visualizatio... . Upper airway (supraglottic) obstruction may make visualization of the glottis, or intubation itself, mechanically impossible. ... . Neck mobility is desirable for any intubation technique and is essential for positioning the patient for optimal DL. Neck mobi... Difficult Bag-Mask Ventilation: ROMAN Difficult Extraglottic Device Placement: RODS Difficult Cricothyrotomy: SMART Measurement and Incidence of Intubation Difficulty Confirmation of Endotracheal Tube Placement Management Decision Making Difficult Airway Failed Airway Methods of Intubation Rapid Sequence Intubation . In the initial phase, the patient is assessed for intubation difficulty and abnormal physiology unless this has already been d... . The goal of preoxygenation is denitrogenation of the alveoli and formation of an oxygen-rich reservoir within the lung’s FRC.... . Airway management can be made more complex by unstable hemodynamics and impaired patient physiology. Although shock states, se... . In this phase, a potent sedative agent is administered by rapid IV push in a dose capable of producing unconsciousness rapidly... . The patient should be positioned for intubation as consciousness is lost. Usually, positioning involves head extension, often ... . Approximately 45 to 60 seconds after administration of the NMBA, the patient is relaxed sufficiently to permit laryngoscopy. ... . After confirmation of tube placement by ETco2, obtain a chest radiograph to confirm that mainstem intubation has not occurred... Delayed Sequence Intubation Awake Oral Intubation Oral Intubation Without Pharmacologic Agents Pharmacologic Agents Neuromuscular Blocking Agents . Succinylcholine is a combination of two molecules of ACh. Succinylcholine is rapidly hydrolyzed by plasma pseudocholinesteras... . Succinylcholine is rapidly active, typically producing intubating conditions within 45 seconds of administration by rapid IV b... . As an ACh analogue, succinylcholine binds to ACh receptors throughout the body, not just at the motor end plate. It is difficu... . The depolarizing action of succinylcholine results in fine chaotic contractions of the muscles throughout the body for several... . Succinylcholine has been associated with severe fatal hyperkalemia when administered to patients with specific predisposing cl... . Succinylcholine has rarely been reported to cause masseter spasm, primarily in children and young adults. The clinical signifi... . Succinylcholine has been associated with malignant hyperthermia, a perplexing and exceptionally rare syndrome of rapid tempera... . Competitive NMBAs are classified according to their chemical structure. The aminosteroid agents include pancuronium, vecuroniu... . When a patient has a contraindication to succinylcholine, rocuronium is the paralytic agent of choice. At a dose of 1.2 mg/kg ... . After intubation, prolonged paralysis may be desired to optimize mechanical ventilation; however, current management is based ... Induction Agents . Etomidate is an imidazole derivative that has been in use since 1972. Its activity profile is similar to that of thiopental, w... . Ketamine, a phencyclidine derivative, has been widely used as a general anesthetic agent since 1970. After an IV dose of 1.5 m... . Propofol is a highly lipophilic alkylphenol with γ-aminobutyric acid (GABA) receptor stimulation activity. Its primary use in... . Given the widespread acceptance and familiarity with etomidate, propofol, and ketamine, other drug classes such as barbiturate... Special Clinical Circumstances Status Asthmaticus Hemodynamic Consequences of Intubation Elevated Intracranial Pressure Hypotension and Shock Potential Cervical Spine Injury Airway Devices and Techniques Direct Laryngoscopy Versus Videolaryngoscopy Videolaryngoscopes Flexible Intubating Scopes Extraglottic Devices . LMAs collectively include a number of commercially available ovoid, silicone mask devices designed to seal above the glottis a... . In addition to LMAs, which sit above the glottis, there are other types of EGDs that travel behind the laryngeal inlet with th... Surgical Airway Management Needle Cricothyrotomy with Transtracheal Jet Ventilation Cricothyrotomy Outcomes References 2 - Mechanical Ventilation and Noninvasive Ventilatory Support Foundations Physiology of Positive-Pressure Breathing Positive End-Expiratory Pressure Noninvasive Techniques Management Decision Making: Noninvasive Versus Invasive Ventilation Approach to Initial Ventilator Settings Noninvasive Ventilation High-Flow Nasal Cannula Mechanical Ventilation of the Intubated Patient Ongoing Management Ventilator-Associated Pneumonia Prevention Troubleshooting the Ventilator Special Clinical Circumstances Status Asthmaticus Acute Respiratory Distress Syndrome Outcomes Complications References 3 - Shock Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Specific Causes Hemorrhagic Shock Septic Shock Cardiogenic Shock Neurogenic Shock Management Decision Making Quantitative Resuscitation Pharmacology Volume Replacement . Standard treatment for hemorrhagic shock historically consisted of rapidly infusing several liters of isotonic crystalloid in ... . Colloids offer the theoretical advantage of a high osmotic pressure, which should help maintain normal intravascular volume. C... . In the setting of hemorrhage or a critically low hemoglobin level (<7 g/dL), we recommend transfusion of PRBCs (1 to 2 units i... Vasopressors Inotropes Antimicrobial Therapy Corticosteroids Special Cases Devices and Procedures Ventilation Source Control Mechanical Circulatory Support and Percutaneous Coronary Intervention Pericardiocentesis and Thrombectomy Outcomes References 4 - Brain Resuscitation Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Elevated Intracranial Pressure Management Decision Making Pharmacology Intracranial Pressure Management Devices and Techniques Cardiopulmonary Resuscitation Reperfusion . Maintaining cerebral oxygen delivery is a mainstay of therapy after ischemic brain injury. Oxygen delivery requires a sufficie... Elevated Intracranial Pressure . Medical treatment for elevated ICP has similarly not been proven effective in randomized controlled trials, and treatment prot... . Surgical options for the management of refractory ICP include decompressive craniectomy and evacuation of intracranial hematom... Maintenance of Body Temperature Targeted Temperature Management Outcomes References 5 - Adult Resuscitation Background and Importance Anatomy, Physiology, and Pathophysiology Management Decision Making Prehospital History and Physical Examination Resuscitation Ventricular Fibrillation and Pulseless Ventricular Tachycardia Pulseless Electrical Activity Asystole Pharmacology Devices and Techniques Monitoring End-Tidal Carbon Dioxide Central Venous Oxygen Saturation Echocardiography Extracorporeal Cardiopulmonary Resuscitation Laboratory Testing Arterial Blood Pressure and Coronary Perfusion Pressure Outcomes Post–Cardiac Arrest Care Hypothermic Targeted Temperature Management Coronary Angiography and Primary Percutaneous Coronary Intervention Antidysrhythmic Therapy Oxygen Debt and Hemodynamic Management References 6 - Pain Management Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Pain Conduction Pathways Pain Detection Information Transmission . All sensory neurons are composed of a cell body located in the dorsal root ganglia. The dorsal root ganglia are connected by n... Pain Transmission . The dorsal horn is the gray matter of the posterior aspect of the spinal cord (Fig. 6.2). The dorsal horn acts as an integrati... . The quantity and type of stimuli that produce pain vary among visceral structures. The myocardium, for example, is sensitive t... . Fibers carrying pain impulses exit the dorsal horn and ascend the spinal cord to the brain. The predominant pathways for pain ... Pain Modulation Central Sensitization Pain Expression Reflex Responses to Pain Endorphin System Acute Versus Chronic Pain Management Decision Making Pain Assessment Oligoanalgesia Pain Measurement Treatment Groups . Symptomatic treatment of pain should be initiated promptly, titrated to an acceptable level of relief, and continued while the... . The assessment of pain in the absence of acute or obvious physical injury requires a great deal of communication skill on the ... . Recurrent pain is a subset of chronic pain; the term describes patients who have symptoms with repeated episodes of similar pa... . Chronic malignant pain is similar to acute pain related to ongoing nociceptive stimulation and similar to chronic pain in its ... . Complex regional pain syndrome (CRPS) is a term that includes most sympathetically maintained neuropathic pain. CRPS type 1 (o... Pharmacologic Therapy Opioids . Opioids bind to specific endorphin system receptors located throughout the nervous system. These receptors suppress pain detec... . Some patients feign or exaggerate pain to receive opioids to abuse medications or sell them to others, an occurrence defined a... . The goal of opioid administration is to attain effective analgesia with minimal adverse effects. The effects of opioids vary w... Specific agents . IV morphine is frequently used for the treatment of acute severe pain in ED patients. Morphine is the opioid analgesic agent w... . Meperidine (Demerol), although once widely used, has several disadvantages compared with morphine and other parenteral opioids... . Hydromorphone is a semisynthetic derivative of morphine that is a potent analgesic agent, frequently used to manage acute pain... . Fentanyl is a synthetic opioid that is highly lipophilic; it produces analgesia within 1 to 2 minutes following IV infusion. F... . Sufentanil is a highly lipophilic synthetic opioid. It has been noted to have fewer cardiac effects than other opioids, and no... . Buprenorphine is a synthetic opioid with a high affinity for the opiate receptor. Buprenorphine has no current indication for ... . Oxycodone is a strong opioid agonist that is highly bioavailable in an oral form. Oxycodone is widely sold in combination with... . Hydrocodone is metabolized in the liver to hydromorphone and is typically given orally. Hydrocodone provides greater pain reli... . Codeine is a weak opioid receptor agonist, usually prescribed in combination with acetaminophen, but has little, if any, role ... . Methadone has several unique features that distinguish it from other opioids. It has no known neurotoxic or active metabolites... . Naloxone is an opioid antagonist that reverses the effects of opioids and is used in the setting of adverse, opioid-induced e... . Tramadol is a synthetic oral analgesic that is a weak mu agonist, with some serotonin and norepinephrine reuptake qualities. I... . Tapentadol is a mu opioid agonist and norepinephrine reuptake inhibitor. It is thought to control acute pain via both these pa... . Historically, pain treatment was withheld from patients with abdominal pain to avoid confounding a diagnosis. These recommenda... Nonopioid Analgesic Agents . Acetaminophen is the first-line agent for treating acute and chronic pain and is the safest pharmacologic option for pain in ... Nonsteroidal Antiinflammatory Drugs Drug interactions with nonsteroidal antiinflammatory drugs . NSAIDs may impair the cardioprotective effect of aspirin, although the available evidence is unclear, and the use of daily asp... . The antiplatelet effects of NSAIDs add to the anticoagulant properties of warfarin, compounding the risk of significant bleedi... . Concurrent use of NSAIDs with angiotensin-converting enzyme (ACE) inhibitors may impair renal function and impair the antihyp... . Patients taking diuretics have a greater risk of developing renal failure due to NSAID-mediated decreased renal blood flow. A... . Patients on corticosteroids have an increased risk of peptic ulcer disease. NSAIDs should generally be avoided in patients con... . NSAIDs enhance lithium reabsorption and may directly reduce lithium excretion, leading to increased lithium levels. CNS sympto... . NSAIDs combine analgesia and antiinflammatory effects with low abuse potential and many different side effects compared to opi... . Ketorolac was the first nonopioid analgesic agent available for parenteral use in the United States. For acute pain management... . Ibuprofen is the most widely used agent in the NSAID class. It is available over the counter in various preparations, includin... . Skeletal muscle relaxants have been advocated as an adjunct to analgesics in managing musculoskeletal pain with a spasm compon... . The analgesic and anesthetic properties of nitrous oxide were discovered more than 200 years ago, and it is one of the origina... . Ketamine is a drug that has typically been used primarily as a dissociative anesthetic for procedural sedation; it is one of t... Local/Regional Anesthesia . Peripheral nerves are responsible for transmitting pain information from pain receptors to the spinal cord. Each fiber consist... . Local anesthetic agents are chemical compounds that consist of an aromatic and amine group separated by an ester (e.g., procai... . True allergies to local anesthetics are rare. When an allergy to local anesthetics is reported, the offending substance is oft... Local and systemic toxicity . Local anesthetic agents, depending on the concentration, can be directly toxic to tissue. Also, there are theoretical concerns... . Systemic toxicity of local anesthetics occurs when a sufficient quantity of the drug accumulates in the body so that sodium ch... . Many techniques can be used to reduce the pain of anesthetic injection (Box 6.7). Distraction by manual methods such as scratc... Topical Anesthesia Topical anesthetics applied to intact skin . A eutectic mixture of local anesthetics (EMLA) is a mixture of lidocaine and prilocaine in an alkaline oil mixture in which th... . Ethyl chloride and fluoromethane sprays are occasionally used for superficial analgesia. The agents evaporate quickly and cool... Agents applied to mucosal surfaces . Cocaine is unique among local anesthetic agents, given that it is a potent vasoconstrictor in addition to being an anesthetic ... . Both 2% and 4% lidocaine solutions are available in a viscous matrix for mucosal surfaces. Gel lidocaine can be used in nasal ... . Tetracaine is a potent ester used for surface anesthesia of the cornea. Tetracaine stings when placed in the eye, but only for... . Almost insoluble in water, benzocaine remains on mucous membranes in the mouth and is commonly used to provide superficial ana... . The combination of lidocaine, epinephrine, and tetracaine, 5 to 10 mL, may be applied to an open wound using sterile cotton, w... Nonpharmacologic Interventions Transcutaneous Electrical Nerve Stimulation Out-of-Hospital Analgesia Outcomes: Treatment Endpoints References 7 - Procedural Sedation and Analgesia Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Management Decision Making Patient Assessment Preprocedural Fasting Personnel Devices and Techniques Supplies and Equipment Recovery Post-procedure Recovery and Discharge Pharmacology Routes of Administration Opioids Fentanyl Morphine Benzodiazepines Midazolam Ketamine Sedative-Hypnotics . Etomidate is a short-acting, sedative-hypnotic agent structurally unrelated to the other PSA agents, with no analgesic prope... . Propofol is another short-acting sedative-hypnotic that is structurally unrelated to the other PSA drugs, with no analgesic ... . Ketamine is commonly combined with propofol (known as “ketofol”) for PSA. The two are thought to have synergistic effects that... . Emergency department experience with agents such as alfentanil and remifentanil for PSA is limited. Alfentanil is an ultra–sho... . Careful titration of medications to the desired level of sedation is generally the goal in PSA. At times, however, unanticipat... . Naloxone is a competitive antagonist of opioids and has been effectively used for the reversal of opioid-induced respiratory ... . Flumazenil is a competitive antagonist of benzodiazepines. Although it reverses the sedation effect of benzodiazepines, it is ... Drug Selection and Administration References 8 - Fever in the Adult Patient FOUNDATIONS Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Untitled Signs Ancillary Testing Diagnostic Algorithm EMPIRICAL MANAGEMENT DISPOSITION 9 - Weakness Foundations Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Diagnostic Algorithm Critical and Emergent Diagnoses Specific Presentations of Neuromuscular Disorders Unilateral Weakness . Weakness involving the combination of arm, hand, or leg with ipsilateral facial involvement is generally caused by a lesion in... . Weakness involving the combination of arm, hand, or leg with contralateral facial involvement indicates a brainstem lesion. A ... . Weakness involving the combination of arm, hand, or leg without facial involvement is most likely to be a result of one of the... . Isolated weakness of one extremity is usually caused by a spinal cord or peripheral nerve lesion. Examination for UMN signs in... Bilateral Weakness . When weakness involves the lower extremities only, the first consideration is a spinal cord lesion. If this is the case, UMN s... . When weakness involves the upper extremities only, the lesion is localized within the central portion of the cervical spinal c... . When weakness involves all four extremities without facial involvement, the primary concern is a cervical spinal cord injury o... . Weakness confined to the proximal portions of the upper extremities only points to a myofiber disorder, provided that there ar... . Weakness involving the distal portions of the extremities only is almost always caused by a peripheral neuropathy (see Box 9.2... Facial Weakness Without Extremity Involvement . Isolated, unilateral weakness of the upper and lower halves of the face is caused by a CN VII problem. Causes for an isolated ... . Facial weakness not limited to CN VII will be associated with some combination of ptosis, binocular diplopia, dysarthria, or d... Empiric Management Disposition References 10 - Cyanosis Foundations Epidemiology Pathophysiology Diagnostic Approach Pivotal Findings Presentation and Symptoms Signs Ancillary Testing Imaging Electrocardiography and Echocardiography Diagnostic Algorithm Critical Diagnoses Emergent Diagnoses Empiric Management Methemoglobinemia and Sulfhemoglobinemia Other Causes of Cyanosis Patient Disposition Discharge References 11 - Syncope Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Electrocardiogram Laboratory Testing Urine Testing Imaging Chest Imaging Neuroimaging Echocardiography Diagnostic and Management Algorithm Risk-Stratification Empiric Management References 12 - Depressed Consciousness and Coma Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Diagnostic Algorithm Empirical Management References 13 - Confusion Foundations Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Diagnostic Algorithm Empirical Management References 14 - Seizures Foundations Epidemiology Pathophysiology Diagnostic Approach Pivotal Findings History Taking and Physical Exam Ancillary Testing Laboratory Testing Imaging Studies Electroencephalography Cardiac Monitoring Differential diagnoses Diagnostic Algorithm Empiric Management Disposition References 15 - Dizziness and Vertigo Foundations Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Physical Examination . The vital signs, including orthostatic changes, may be the key to identifying a cardiovascular etiology or drug effect as the ... . Carotid or vertebral artery bruits suggest atherosclerosis and risk for TIA or stroke. The vertebral artery can be auscultated... . The presence of CN deficits suggests a space-occupying lesion in the brainstem or cerebellopontine angle, such as an acoustic... . Positional testing confirms the diagnosis of BPPV. The Hallpike test, also known as the Dix-Hallpike test or the Nylen-Baran... . HINTS (Head Impulse test, Nystagmus, Test of Skew) is a bedside oculomotor examination test that has been proposed as a way to... Ancillary Testing . Acute vertigo by itself does not warrant urgent computed tomography (CT) or MRI in all patients, particularly patients in whom... Diagnostic Algorithm Empirical Management Disposition References 16 - Headache Background and Importance Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Diagnostic Algorithm Empirical Management References 17 - Diplopia Foundations Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings . The history begins by determining if the diplopia is monocular or binocular. Additional information helpful in formulating the... Physical Exam . The external eye exam includes an exam of the orbital and periorbital structures. The conjunctiva is examined for signs of inj... . The patient should undergo a careful pupillary examination, looking for signs of asymmetry. Patients with a CN III palsy may h... . The extraocular muscles of the eye include the lateral rectus, which is innervated by the abducens nerve (cranial nerve VI), t... . Structures of the posterior chamber include the retina, the optic nerve, the optic disk, the central retinal artery, the retin... . Structures of the anterior chamber include the sclera, conjunctiva, cornea, iris, lens and the aqueous humor. Examination incl... Signs and Symptoms . Monocular diplopia is present only if the patient complains that the diplopia persists in the affected eye with the normal eye... Binocular diplopia . An orbitopathy refers to any disease that affects the orbit and its contents. A structural orbitopathy can be caused by orbita... . There are multiple causes of an isolated oculomotor nerve palsy including hypertensive or diabetic vasculopathy, a demyelinati... . A focal brainstem lesion, seen in multiple sclerosis, may result in isolated diplopia. However, localized brainstem lesions us... . Diplopia that is variably triggered in multiple directions, without a distinct structural or neuropathic cause, implies a neur... Ancillary Testing Diagnostic Algorithm Empirical Management Management Algorithm References 18 - Red and Painful Eye Epidemiology and Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Visual Acuity Visual Field Testing External Examination Extraocular Muscle Function Pupillary Evaluation Pressure Determination Ancillary Testing Swinging Flashlight Test Slit-Lamp Examination Direct Funduscopic Examination Topical Anesthetics Imaging Laboratory Testing Diagnostic Algorithm Critical Diagnoses Emergent Diagnoses Urgent Diagnoses Empiric Management References 19 - Sore Throat Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms and Signs Ancillary Testing Imaging Diagnostic Algorithm Critical and Emergent Diagnoses Empiric Management References 20 - Hemoptysis Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Diagnostic Algorithm Critical Diagnoses Bronchoscopy Empirical Management References 21 - Dyspnea Foundations Epidemiology Pathophysiology Diagnostic Approach Differential Diagnosis Considerations Pivotal Findings Symptoms .. The description of symptoms may provide clues to a diagnosis. For example, chest tightness is fairly specific to bronchoconst... .. Chronic or progressive dyspnea usually denotes primary cardiac, pulmonary, or, less commonly, neuromuscular disease. Many of ... .. Orthopnea can result from left-sided heart failure, COPD, or neuromuscular disorders.4 It can be one of the earliest symptom... .. Anxiety or overwhelming fear, particularly if it precedes the onset of dyspnea, may point to panic attack or psychogenic dysp... Signs Ancillary Testing Diagnostic Algorithm Critical Diagnoses Emergent Diagnoses Empirical Management References 22 - Chest Pain Foundations Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings History Physical Examination Ultrasound Ancillary Studies Diagnostic Algorithm Empirical Management References 23 - Abdominal Pain DIAGNOSTIC APPROACH Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Laboratory Tests Imaging Studies DIAGNOSTIC ALGORITHM Critical Diagnoses Emergent Diagnoses EMPIRIC MANAGEMENT REFERENCES 24 - Jaundice Pathophysiology Normal Bilirubin Metabolism Abnormalities in Bilirubin Metabolism Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Laboratory Tests Imaging Diagnostic Algorithm Empirical Management References 25 - Nausea and Vomiting Epidemiology Pathophysiology Diagnostic Approach Differential Diagnosis Considerations Pivotal Findings Symptoms Signs Ancillary Studies Diagnostic Algorithm Empirical Management Adults Pediatrics Special Situations Opioid-Induced Vomiting Headache Pregnancy Chemotherapy Cyclical Vomiting Syndrome and Cannabinoid Hyperemesis Syndrome Vertigo Gastroparesis Disposition References 26 - Gastrointestinal Bleeding Foundations Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Laboratory Testing Electrocardiogram Nasogastric Aspirate Testing Imaging Diagnostic Algorithm Management Empiric Treatment Resuscitation Blood Product Transfusion Pharmacologic Therapy Balloon Tamponade Definitive Treatment References 27 - Diarrhea Introduction Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Signs and Symptoms Ancillary Testing . Leukocytosis has been reported in C. difficile infections, although an isolated white blood cell count elevation is not sensit... . Fecal leukocytes are not sufficiently specific or sensitive as the sole criterion to determine which patients should be treate... . There are multiple tests available to identify the specific pathogen causing a patient’s symptoms; however, the results are ge... . Stool cultures are generally not indicated in the ED given their low sensitivity and delayed results. Stool culture panels for... . Testing for C. difficile should be considered if the patient is immunocompromised or reports antibiotic use during the precedi... . This assay should be considered when there is a known outbreak or if the presentation occurs in an endemic area. It should als... . These tests may be useful in patients with chronic diarrhea (Entamoeba histolytica and Cryptosporidium), patients with a histo... . Giardia antigen assay and serologic testing for amebiasis should be considered in patients exposed to poor sanitation or those... . Radiographic studies are not commonly used in the evaluation of acute diarrhea. Plain radiography is rarely indicated. If peri... Gastrointestinal Referral Diagnostic Algorithm Critical Diagnoses Emergent Diagnoses Empiric Management Rehydration Antibiotics Antimotility Agents Probiotics Disposition References 28 - Constipation Foundations Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Ancillary Testing Critical Diagnoses Emergent Diagnoses Empirical Management References 29 - Acute Pelvic Pain Epidemiology Pathophysiology Diagnostic Approach Differential Considerations Pivotal Findings Symptoms Signs Ancillary Testing Laboratory Tests Imaging Diagnostic Algorithm Empirical Management References 30 - Vaginal Bleeding Background and Importance Pathophysiology Nonpregnant Patients Pregnant Patients Diagnostic Approach Differential Considerations Nonpregnant Patients Pregnant Patients Pivotal Findings Symptoms Signs Ancillary Testing Diagnostic Algorithm Empiric Management Disposition References 31 - Back Pain Foundations Background and Importance Pathophysiology Diagnostic Approach Differential Considerations Myelopathy Radiculopathy Spondylosis Disc Herniation Spinal Infections Spinal Tumors Cauda Equina Syndrome Acute Transverse Myelitis Mechanical Back Pain Chronic Back Pain Pivotal Findings Symptoms Signs Ancillary Testing Laboratory Tests Imaging Studies Abdominal Ultrasound Plain Film Radiographs Computed Tomography Scan Magnetic Resonance Imaging Diagnostic and Management Algorithms Critical Diagnoses Emergent Diagnoses Empiric Management Mild to Moderate Back Pain Severe Back Pain Chronic Back Pain Disposition Acknowledgments References 32 - Multiple Trauma Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Primary Survey Secondary Survey Differential Diagnoses Diagnostic Testing Laboratory Evaluation Radiographic Evaluation Management Out-of-Hospital Management Emergency Department Management Disposition References 33 - Head Trauma Foundations Background and Importance Anatomy and Pathophysiology Anatomy . The scalp consists of five tissue layers (Fig. 33.1). The skull is comprised of the frontal, ethmoid, sphenoid, and occipital ... . The brain is a semisolid structure that weighs approximately 1400 g (3 lb.) and occupies approximately 80% of the cranial vaul... Pathophysiology . The brain has an extremely high metabolic rate, accounting for approximately 20% of the entire oxygen consumption of the body ... . Increased ICP is defined as a CSF pressure greater than 15 mm Hg (or 195 mm H2O) and is a frequent consequence of a severe TBI... . Progressive hypertension associated with bradycardia and diminished respiratory effort is a specific response to acute, poten... Altered Levels of Consciousness Definitions and Patterns of Injury Traumatic Brain Injuries: Severe, Moderate, and Mild Direct and Indirect Injuries . Direct head trauma occurs when the head is struck, or its motion is suddenly arrested, by an object. The resulting damage to t... . In indirect brain injury, the cranial contents are set into motion by forces other than the direct contact of the skull with a... Neurochemical Cascade Penetrating Head Trauma Scalp Wounds Skull Fractures Linear Fractures Depressed Fractures Basilar Fractures Extra-Axial and Intra-Axial Intracranial Injuries Extra-Axial Injury . An EDH is bleeding that occurs between the inner table of the skull and dura. Most EDHs result from a direct-impact injury th... . An SDH is a hemorrhage that occurs between the dura and brain and is usually caused by acceleration-deceleration injuries. SD... . A traumatic SAH is blood within the CSF and meningeal intima and probably results from tears of small subarachnoid vessels. Tr... . A SDHG is a collection of clear, xanthochromic blood-tinged fluid in the dural space. The pathogenesis of an SDHG is not cert... Intra-Axial Injury . Prolonged traumatic coma not caused by mass lesions or ischemic insult is thought to result from diffuse axonal injury (DAI). ... . Contusions are bruises on the surface of the brain, usually caused by impact injury. Contusions are produced when parenchymal ... . Intracerebral hematomas (ICHs) are formed deep within the brain tissue and are usually caused by shearing or tensile forces th... . Primary traumatic intracerebellar hematomas are rare but can occur after a direct blow to the occipital area. Often, these pat... Primary and Secondary Brain Injuries Secondary Systemic Insults . Hypotension, defined as SBP less than 90 mm Hg, has been found to have a negative impact on severe brain injury outcome. Syste... . Hypoxia, defined as a Po2 less than 60 mm Hg, is relatively common in the brain-injured patient. Causes include: (1) transien... . Paco2 is one of the most potent drivers of CBF. Hypocarbia (Paco2 ≤35 mm Hg) results in vasodilation, while hypercarbia (Paco2... . Anemia caused by blood loss can be detrimental to the head-injured patient by reducing the oxygen-carrying capacity of the b... . Hyperpyrexia (core body temperature >38.5°C [101.3°F]) is also correlated with worse outcomes after TBI, and its magnitude and... Cerebral Herniation Syndromes Uncal Herniation Central Transtentorial Herniation Cerebellotonsillar Herniation Upward Transtentorial Herniation Clinical Features Physical Examination Acute Neurologic Examination . The goals of the acute neurologic assessment of head trauma patients include detection of life-threatening injuries and ident... . The GCS is a 15-point scale used to quantify the patient’s LOC and as an objective method of following the patient’s neurolog... . An evaluation of the patient’s pupil size and responsiveness is performed early in the initial assessment of the head-injured... . The patient’s acute motor examination assesses for strength and symmetry. If the patient is not cooperative or is comatose, mo... . In the acute setting, brainstem activity is assessed by the patient’s respiratory pattern, pupillary size, and eye movements. ... Common Presentations of Specific Lesions Epidural Hematoma Subdural Hematoma Traumatic Subarachnoid Hemorrhage Subdural Hygroma Traumatic Axonal Injury Cerebral Contusion Intracerebral Hematoma Traumatic Intracerebellar Hematoma Differential Diagnoses Diagnostic Testing Laboratory Tests Neuroimaging . Skull radiography after head trauma has long been replaced by cranial CT, which is the cornerstone of imaging for acute head t... . Noncontrast CT of the head is the diagnostic standard for identifying intracranial injury in the ED. This scan delineates acut... . This is often associated with missile wounds that penetrate the sinuses but can be caused by free air sucked into the penetrat... . On CT scan, an EDH appears hyperdense, biconvex, ovoid, and lenticular. The EDH does not usually extend beyond the dural attac... . Unlike EDHs, SDHs often extend beyond the suture lines (Fig. 33.8). An SDH may follow the contour of the tentorium and be dete... . A noncontrast CT scan allows the diagnosis to be made, with increased density noted within the basilar cisterns. Blood can als... . On CT, SDHGs appear crescent shaped in the extra-axial space; the density is the same as that of CSF. Bilateral SDHGs are com... . Diffuse TAI is the most common CT finding after severe head trauma, estimated to occur in over 50% of all comatose head injure... . Non–contrast-enhanced CT is the best diagnostic test to discover contusions in the early posttraumatic period. These appear h... . An ICH may be detected on the first CT scan immediately after injury but often is not seen for several hours or days. Unlike c... . Often, these patients have an associated skull fracture, posterior fossa EDH or SDH, or supratentorial contrecoup hematomas an... . On CT scans, diffuse edema manifests as bilateral compression of the ventricles, loss of definition of the cortical sulci, or ... Management Out-of-Hospital Care . The ultimate goal in the field is to prevent or minimize hypoxia. Out-of-hospital airway protocols balance the risks of emer... . Avoiding and managing hypotension are critical elements of the prehospital treatment of the head-injured patient.50 The evalu... . Many severely head-injured patients are initially combative or agitated. Transporting an agitated patient who is fighting aga... Emergency Department Management . In the ED, management of patients with severe head trauma is in accordance with ATLS (Advanced Trauma Life Support) protocols.... . Primary airway compromise in the setting of head trauma may result from craniofacial or neck trauma, bleeding, or vomiting. Se... . While hypotension can occasionally be attributed to isolated head injury, it is almost always secondary to another systemic in... . Osmotic therapy should be guided by findings on ICP monitoring. Prior to initiation of such monitoring, brain-directed osmoti... . Under normal conditions, Paco2 is the most powerful determinant of CBF and, between a range of 20 and 80 mm Hg, CBF is linearl... . In patients with impending herniation who do not respond to first-line therapies, cranial decompression may temporarily rever... . Patients taking warfarin anticoagulants should have these medications reversed in the case of ongoing intracranial bleeding. V... . Recombinant factor VIIa (rFVIIa) is a hemostatic agent that was originally developed to treat bleeding in hemophiliacs. Limite... . Hyperpyrexia has been suggested to worsen outcomes after severe TBI. Induced therapeutic hypothermia decreases ICP and has bee... . Though rare, acute symptomatic seizures may occur as a result of severe TBI.76 Such posttraumatic seizures (PTSs) are classifi... . Although the practice was once widespread, there is no evidence to support the use of antibiotic prophylaxis for the preventio... Other therapies . Corticosteroids have no benefit for patients with head trauma, and in fact demonstrate an increase in adverse events, includin... . Barbiturate therapy has historically been used in severely brain-injured patients to reduce cerebral metabolic demands of the... . Invasive ICP monitoring has been a mainstay of management for severe TBI, although its utility has recently been called into q... . In randomized trials of patients with moderate to severe TBI, erythropoietin did not reduce severe neurologic dysfunction or i... . Progesterone has been shown to improve neurologic outcome in early-phase trials involving patients with TBI. In a double-bli... . Hyperbaric oxygen therapy following severe, acute TBI provides the injured brain with an increased partial pressure of oxygen ... Management of Specific Injuries . For briskly bleeding scalp wounds, rapid hemostasis is a priority. Initially, hemostasis may be achieved by the application of... . A noncontrast head CT scan with bone windows is the imaging modality of choice for patients with suspected skull fractures or ... . Linear skull fractures are clinically important if they cross the middle meningeal groove or major venous dural sinuses; they ... . When a depressed fracture occurs, traumatic impact drives the bone piece below the plane of the skull. The edges of the depres... . Basilar fractures are the result of considerable impact force and are highly associated with underlying brain injury. Emergenc... Extra-axial lesions . Consensus guidelines support rapid surgical evacuation for any patient who has mass effect on a CT scan or progressive neurolo... . SDH is often associated with significant brain injury. Further, delays in clinical signs and symptoms and the older mean age o... . In the absence of other brain injury, tSAH generally carries a favorable prognosis. The most serious complication of tSAH is w... . If SDHGs are asymptomatic, observation is a reasonable approach. Otherwise, they are surgically evacuated. Mortality approache... Intra-axial lesions . Patients with brain contusions can often be treated conservatively, although almost half will have significant progression on ... . Many patients with an ICH require emergent intervention or surgery to lower elevated ICP. Mortality is low in patients who are... . Mortality from isolated traumatic intracerebellar hematoma is very high. Emergent neurosurgical consultation is indicated Complications and Outcome Central Nervous System Infections . Posttraumatic meningitis can be caused by a variety of microbes, depending on the portal of bacterial entry. Patients have typ... . Brain abscesses develop infrequently after penetrating missile injuries to the head. Abscesses can also develop after open dep... . Cranial osteomyelitis can occur after penetrating injury to the skull. The clinical manifestations include pain, tenderness, s... Medical Complications . The injured brain is a source of tissue thromboplastin that activates the extrinsic clotting system. Disseminated intravascula... . Pulmonary complications in the hours to days following TBI are common. Acute lung injury has been theorized to occur from a va... . Cushing noted a connection between cardiac dysrhythmias and intracranial bleeding in the early 20th century, and a variety of ... Disposition Clinical Features Physical Examination Head and Neck Mental Status and Alertness Cranial Nerves Cognitive Function (Attention, Memory, Concentration) Vestibular Function (Balance, Gait, and Eye Movements) Differential Diagnoses Diagnostic Testing Neuroimaging in the Emergency Department with Computed Tomography Other Neuroimaging Modalities . CT is the imaging modality of choice for initial screening to exclude serious traumatic intracranial lesions in MTBI. However,... . A significant advancement in the imaging of MTBI has been the development of susceptibility-weighted imaging (SWI). This tech... . DTI uses MRI technology to analyze the movement of water molecules in the white matter of the brain and provides the opportuni... . Vascular imaging such as CT angiography and MR angiography are not recommended routinely for patients with MTBI unless there i... Ancillary Studies . Laboratory tests are not needed for patients with isolated MTBI except for a bedside glucose level in those with a GCS score l... . Neuropsychological testing is used to assess cognitive function after MTBI and includes in-depth testing of memory, attention... Disposition Complications Postconcussive Syndrome Seizures Posttraumatic Transient Cortical Blindness Special Populations with Mild Traumatic Brain Injury Mild Traumatic Brain Injury and Sports-Related Concussion Military Personnel and Blast Injury Anticoagulated Patients . Most clinical decision guidelines for determining need for CT scan exclude patients who are taking anticoagulants such as warf... . The most serious site of bleeding for children and adults with inherent bleeding disorders, such as hemophilia, is the CNS. In... Head Trauma in Older Adults References 34 - Facial Trauma Background and Importance Anatomy, Physiology, and Pathophysiology Bones Nerve Supply Ears Eyes Nose Mouth Temporomandibular Joint Soft Tissue, Vasculature, and Specialized Glands Pathophysiology Clinical Features History Physical Examination . In addition to the examination of lacerations and contusions, the face should be evaluated for symmetry. The appearance of the... . The integrity of the mouth and nasal complex may be evaluated by listening to the patient’s speech. A muffled or hoarse voice ... . Otoscopy is performed to evaluate the integrity of the external canal, look for hemotympanum, and assess for otorrhea. Subcuta... . The nose is palpated for tenderness, crepitus, or abnormal movement; then each naris is held closed in turn to ensure that the... Neurologic Examination Soft Tissue Injuries and Lacerations Mouth Cheeks Nose Ears Eyes Fractures and Dislocations Forehead Orbit Midface Zygoma Mandible Dental and Alveolar Trauma Temporomandibular Joint Diagnostic Testing Imaging Management Out-of-Hospital Care Emergency Department Treatment Disposition References 35 - Spinal Trauma FOUNDATIONS Background and Importance Anatomy and Physiology Pathophysiology Classification of Spinal Column Injuries . Atlanto-occipital and atlantoaxial joint dislocation can occur with or without associated fractures of the odontoid (Fig. 35.... . Trauma to the head directed in an anteroposterior (AP) direction may result in fracture of the odontoid process above the tran... . Rotary atlantoaxial dislocation is an unstable injury visualized best on open-mouth odontoid radiographs (Fig. 35.15) or comp... . Fracture of the posterior neural arch of the atlas (C1) results from compression of the posterior elements between the occiput... . Vertical compression injuries occur in the cervical and lumbar regions, which are capable of straightening at the time of impa... Classification of Spinal Cord Injuries . The spinal cord may be injured by three broad categories of injury patterns. First, penetrating trauma or massive blunt trauma... . The maximum neurologic deficit after blunt spinal cord trauma is often not seen on initial examination and may, instead, progr... Classification of Cervical Soft Tissue Injuries CLINICAL FEATURES Neurologic Evaluation Spinal Cord Lesions Complete Spinal Cord Lesions Incomplete Spinal Cord Lesions DIFFERENTIAL DIAGNOSES DIAGNOSTIC TESTING Radiographic Evaluation Indications Cervical Plain Radiographs Thoracolumbar Plain Radiographs . The inspection of the lateral cervical spine film should be methodical and complete. It is helpful to remember the ABCs of int... MANAGEMENT Spinal Column Stabilization Out-of-Hospital Care Emergency Department Airway Management Spinal Shock Pharmacologic Treatment for Incomplete Cord Injury Associated Injuries Cardiopulmonary Gastrointestinal and Genitourinary Skin Definitive Treatment and Prognosis DISPOSITION Cervical Soft Tissue Injuries Minor Fractures REFERENCES 36 - Neck Trauma Foundations Background and Importance Anatomy and Physiology Pathophysiology Vascular Injuries Pharyngoesophageal Injuries Laryngotracheal Injuries Hanging Clinical Features Vascular Injuries Pharyngoesophageal Injuries Penetrating injury Blunt Injury Laryngotracheal Injuries Penetrating injury Blunt injury Hanging Miscellaneous Differential Diagnoses Diagnostic Testing Vascular Injuries Penetrating Injury Blunt injury Pharyngoesophageal Injuries Penetrating injury Blunt Injury Laryngotracheal Injuries Penetrating injury Blunt Injury Hanging Management Vascular Injuries Penetrating injury Blunt injury Pharyngoesophageal Injuries Penetrating injury Blunt Injury Laryngotracheal Injuries Hanging Miscellaneous Disposition Penetrating Injury Blunt Injury References 37 - Thoracic Trauma Rib Fracture Foundations Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Sternal Fracture Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Management Nonpenetrating Ballistic Injury Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Management Disposition Pulmonary Contusion and Laceration Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Laboratory Radiology Management Pneumothorax Foundations Background and Importance Pathophysiology . A pneumothorax is considered simple or closed (Fig. 37.5) when there is no communication with the atmosphere or any shift of t... . A communicating pneumothorax (Fig. 37.7) is associated with a defect in the chest wall and most commonly occurs in combat inju... . The progressive accumulation of air under pressure within the pleural cavity, with shift of the mediastinum to the opposite he... Clinical Features Diagnostic Testing Occult Pneumothorax Management Simple Pneumothorax Communicating Pneumothorax Tension Pneumothorax Hemothorax Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Management Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Management Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Management Myocardial Concussion Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Laboratory Tests and Electrocardiogram Management Disposition Myocardial Contusion Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Laboratory Tests and Electrocardiogram . The right ventricle is far more likely to be injured than the left ventricle because of its anterior position in the thorax an... . Creatine kinase (CK) is nonspecifically increased in trauma patients owing to associated skeletal muscle injury, and CK-MB le... Imaging Management Disposition Myocardial Rupture Foundations Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Diagnostic Testing Management Penetrating Cardiac Trauma Acute Pericardial Tamponade Foundations Background and Importance Pathophysiology Clinical Features Diagnostic Testing Radiology . Ultrasound enables rapid, accurate, and noninvasive diagnosis of pericardial tamponade.22 This study can be performed at the b... . The radiographic evaluation of the cardiac silhouette in acute pericardial tamponade generally is not helpful, unless a trauma... Electrocardiography Management Emergency Department Thoracotomy . Although it is tempting to perform “life-saving” EDT on all traumatic arrest victims in the ED, there are many cases in which... Blunt Aortic Injury Foundation Background and Importance Pathophysiology Clinical Features Diagnostic Testing Chest Radiography Chest Computed Tomography Scan Management Stabilization and Empirical Therapy Definitive Management . A number of studies indicate that success and complication rates are likely better than those of traditional open surgical rep... Esophageal Perforation Foundations Background and Importance Pathophysiology Clinical Features Iatrogenic Foreign Bodies Caustic Burns Penetrating and Blunt Trauma Spontaneous Rupture Diagnostic Testing Radiology Endoscopy Management References 38 - Abdominal Trauma Foundations Background and Importance Penetrating Abdominal Trauma Blunt Abdominal Trauma Anatomy and Physiology Pathophysiology Penetrating Abdominal Trauma . Stab wounds occur most commonly in the upper quadrants and are caused by a variety of sharp implements besides knives. However... . The science of ballistics is complex, but a few basic principles are helpful in understanding the pathophysiologic processes. ... Blunt Abdominal Trauma . Unrestrained passengers are at an unequivocally greater risk of intra-abdominal injury than their restrained counterparts. Th... . Abdominal injuries may be sequelae of various medical procedures. External cardiac compressions, manual chest thrusts to clear... Clinical Features Specific Clinical Presentations Penetrating Abdominal Trauma . The number of stabs inflicted, type and size of the instrument, posture of the victim relative to the direction of assault, es... . Clinically helpful information for gunshot wound victims includes the weapon used, its distance from the victim when shot, the... Blunt Abdominal Trauma Physical Examination Penetrating Abdominal Trauma . Serial physical examination performed by the same observer is useful in appropriately staffed and established trauma centers, ... . As with blunt or other modes of penetrating trauma, there are limitations to physical examination of patients with abdominal g... Blunt Abdominal Trauma Differential Diagnoses Diagnostic Testing Ultrasonography Laboratory Testing Radiology Plain Radiographs Computed Tomography Magnetic Resonance Imaging Management Penetrating Abdominal Trauma Stab Wounds . In approaching the management of stab wounds to the anterior abdomen, the clinician is faced with three fundamental tasks. The... . Various clinical factors can be used to determine the need for emergent laparotomy (Table 38.1) based on the likelihood of ass... . If clinical indications for laparotomy are absent, the logical next step is assessing the wound tract itself. The presence of ... . In this algorithm, patients requiring an operation on clinical grounds have proceeded to laparotomy, and those in whom periton... . Even a single stab wound to the low chest can violate the mediastinum, thoracic cavity, diaphragm, peritoneal cavity, and retr... . The incidence of retroperitoneal injuries after stab wounds to the flank and back is greater than with injury to the anterior ... Gunshot Wounds . Abdominal gunshot wounds enter the peritoneal cavity in approximately 80% of cases, and in more than 90% of those with penetra... . Fifty percent of patients with gunshot wounds to the low chest have intraperitoneal injuries. Clinical indications for emergen... . CT scan is highly accurate for identification of retroperitoneal injury and is the diagnostic test of choice in a stable patie... Blunt Abdominal Trauma Operative Versus Nonoperative Management Pelvic Fracture Multiple System Injury Bedside Procedures Diagnostic Peritoneal Lavage Local Wound Exploration Resuscitative Endovascular Balloon Occlusion of the Aorta Therapeutic Angioembolization Disposition Consultation Transfer References 39 - Genitourinary Trauma Foundations Background and Importance Anatomy and Physiology Pathophysiology Renal Trauma Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Ureteral Trauma Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Bladder Trauma Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Urethral Trauma Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Genital Trauma Clinical Features Differential Diagnoses Diagnostic Testing Imaging Management Disposition References 40 - Peripheral Vascular Trauma Background and Importance Anatomy and Physiology Upper Extremity Lower Extremity Pathophysiology Penetrating Trauma Blunt Trauma Vascular Injuries Complete occlusive injury . The most common vascular injury is complete transection, in which distal flow is effectively eliminated. Cleanly transected ar... . Intraluminal thrombosis (Fig. 40.3) may occur in an injured artery acutely (within 24 hours) or may be delayed for many months... . The precise cause and incidence of significant reversible arterial spasm after trauma are unknown. In the case of arterial tra... Nonocclusive injuries . An intimal flap occurs when there is a break in the vessel intima, generally from excessive stretch or concussive forces. Alth... . A true aneurysm contains all three layers of the vessel wall (intima, media, and adventitia) and is rarely caused by trauma. A... . An AVF is formed when both an artery and an adjacent vein are injured. Higher-pressure arterial flow is directed into the low... Compartment Syndrome Clinical Features Hard Findings of Vascular Injury Soft Findings of Vascular Injury Asymptomatic High-Risk Wounds History Physical Examination Differential Diagnoses Diagnostic Testing Plain Radiography Pulse Oximetry and Near-Infrared Spectroscopy Handheld Doppler Arterial Pressure Index and Ankle-Brachial Index Ultrasound Computed Tomography and Magnetic Resonance Imaging Arteriography Diagnosis of Specific Vascular Injuries Management Major Vascular Injuries Upper Extremity Arterial Injuries Lower Extremity Arterial Injuries Late Complications of Arterial Injury Venous Injuries Minor Vascular Injuries Arterial Spasm Antibiotics Disposition References 41 - General Principles of Orthopedic Injuries Overall Foundations Background and Importance Fractures Foundations Anatomic Location of a Fracture: Nomenclature Anatomic Descriptors Descriptive Modifiers Fracture Eponyms and Mechanistic Names Epiphyseal Fractures Clinical Features of Fractures Fracture Healing Complications of Fractures Infection (Osteomyelitis) Hemorrhage Vascular Injuries Nerve Injuries Compartment Syndrome . Increased pressure in a closed, non-expandable compartment essentially represents a mismatch between the volume of that space... . Compartment syndrome theoretically can develop in any location where neuromuscular tissue is contained within a limited or con... . Compartment syndrome is a clinical diagnosis. In a conscious and fully oriented patient, pain that is disproportionate to the ... . Clinical examination remains the diagnostic cornerstone of acute compartment syndrome, which can then be confirmed by the meas... . Complete fasciotomy is the only treatment that can reliably normalize elevated compartment pressure. Surgery should be perform... Avascular Necrosis Fat Embolism Syndrome Fracture Blisters Complications of Immobilization and Hospitalization Damage Control Orthopedic Surgery Differential Diagnoses Diagnostic Testing Plain Radiography Special Imaging Techniques . Although conventional radiography remains the initial imaging study of choice for skeletal trauma, CT offers a more detailed a... . MRI constitutes the most advanced noninvasive examination of orthopedic structures, delineating lesions of bone, cartilage, li... . Point of care ultrasound can be an effective tool for the diagnosis of fractures when conventional radiography is unavailable,... Laboratory Testing Management Field Care . Suspected fractures should be splinted in the field to limit damage to muscles, nerves, vessels, and skin and to prevent a clo... Emergency Department Care Upper Extremity . Sling-and-swathe bandages are useful in immobilizing the shoulder, humerus, and elbow. They are commonly used after reductio... . A simple sling of the arm on the affected side is sufficient to support the clavicle, improving healing immobilization and rel... . Well-fitting, customized plaster splints can be fashioned easily to immobilize the elbow, forearm, wrist, and hand. The advan... Casts Forearm and Wrist Splints Lower Extremity . Immobilization of the ankle can be accomplished by numerous methods. Plaster or fiberglass splints can be used temporarily for... Thermal Therapy Disposition Subluxation and Dislocations Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Soft Tissue Injuries Sprains Foundations Clinical Features Differential Diagnoses Diagnostic Testing . Plain radiography is indicated in some, but not all, cases of suspected sprain to rule out a fracture. From a medical standpoi... . MRI is generally not indicated acutely but may be indicated in follow up when significant ligamentous injuries that may requir... Management Disposition Strains Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Tendinitis and Tendinosis Foundations Clinical Features Differential Diagnosis Diagnostic testing Disposition Bursitis Foundations Clinical Features Diagnostic Modalities Management Disposition Other Soft Tissue Conditions References 42 - Hand Injuries Anatomy Surface Anatomy and Skin Skeletal Anatomy and Ligaments Musculature and Tendons . The intrinsic hand muscles include the muscles of the thenar and hypothenar eminences as well as the adductor pollicis, lumbri... . The extrinsic hand muscles are those that originate proximal to the wrist and insert within the hand. Most extrinsic hand musc... . The extensors tendons pass through the dorsum of the wrist at 6 different compartments and are innervated by the radial nerve ... . The anterior forearm contains muscles responsible for flexion of the wrist, hand, and digits and can be divided into an anteri... . The digital flexor sheath of the hand is a closed system of synovial membranes that is divided into membranous and retinacular... Blood Supply . The radial and ulnar arteries are primarily responsible for blood supply to the hand. The radial artery courses through the an... Venous and Lymphatic System Innervation and Sensory Systems Regional Blocks Digital Block Metacarpal and Transthecal Blocks Wrist Blocks . The radial artery at the volar surface of the wrist is palpated. Immediately lateral (radial) to this region, after aspirating... . The tendon of the flexor carpi radialis at the volar surface of the wrist is palpated. The needle is inserted over the median ... . The needle should be inserted between the ulnar artery and the flexor carpi ulnaris tendon and advanced approximately 1 cm. If... Splinting Ring Removal Specific Hand Injuries Phalanx and Metacarpal Fractures Clinical Features Differential Diagnoses Diagnostic Testing Management Phalanx Fractures Distal Phalanx Fractures Clinical Features Differential Diagnoses Diagnostic Testing Management Middle Phalanx Fractures Clinical Features Differential Diagnoses Diagnostic Testing Management Proximal Phalanx Fractures Clinical Features Differential Diagnoses Diagnostic Testing Management Metacarpal Fractures Clinical Features Differential Diagnosis Diagnostic Imaging Management Thumb Fractures Clinical Features Differential Diagnoses Diagnostic Testing Management Joint Injuries Clinical Features Differential Diagnoses Diagnostic Testing Management Interphalangeal Joint Injuries Clinical Features Differential Diagnoses Diagnostic Testing Management Metacarpophalangeal Joint Injuries Clinical Features Differential Diagnoses Diagnostic Testing Management Carpometacarpal Joint Injuries Clinical Features Differential Diagnoses Diagnostic Testing Management Thumb Dislocations and Ligamentous Injuries Clinical Features Differential Diagnoses Diagnostic Testing Management Tendon Injuries Extensor Tendon Injuries Clinical Features . This zone includes the distal phalanx and DIP joint. Terminal tendon disruption from sudden flexion of the extended DIP joint ... . Injuries occur over the middle phalanx and are usually due to a laceration. Rarely, a mallet deformity will form from a lacera... . Injuries in this zone involve the PIP joint and the central slip. Boutonnière injury (flexion at the PIP joint with hyperexten... . This zone includes injuries over the proximal phalanx. Like in zone II, injuries usually occur from lacerations. The tendon is... . Injuries at this zone involve the sagittal band at the MCP joint. The most common injury is to the radial sagittal band of the... . Injuries at this zone occur over the metacarpals, most frequently secondary to lacerations. Complete lacerations are often mis... . Lacerations over the carpals and extensor retinaculum account for most injuries at this zone, though injuries may also occur w... Differential Diagnoses Diagnostic Testing Management . Most mallet finger injuries are successfully treated with immobilization, though injuries accompanied by fracture dislocations... . Incomplete lacerations can be managed with simple closure and splinting of the DIP in extension for 2 weeks. Complete lacerati... . Central slip disruptions (boutonnière injuries) are treated by splinting the PIP joint in extension for 4 to 6 weeks followed ... Zone IV Extensor Injuries Management . Stable sagittal band injuries (type I) can be treated with buddy or dynamic taping for 3 to 4 weeks. Acute injuries with sublu... . Clean, complete tendon lacerations may be repaired by an EM physician, though we recommend discussion with a hand specialist f... . If there is no need for immediate surgical intervention (such as gross contamination), wounds should be thoroughly irrigated f... Disposition Flexor Tendon Injuries Clinical Features Differential Diagnoses Diagnostic Studies Management Disposition Trigger Finger Clinical Features Differential Diagnoses Diagnostic Testing Management Finger and Nail Bed Injuries Nail Bed Injuries . The nail bed is frequently injured in a manner that ranges from minimal to severe. Injury occurs after direct trauma to the fi... . When evaluating a patient with a suspected nail bed injury, the EM clinician should also consider an underlying tuft fracture,... . Imaging is needed to determine if there is fracture of the finger tuft. PA, lateral, and oblique radiographs will identify a f... . For a subungual hematoma covering greater than 50% of the nail bed, the typical practice is to trephinate, or create an openin... . The injuries resulting in subungual hematomas with non-displaced fractures can be followed up by primary care physicians as m... Amputations Fingertip Amputations . Amputations of the fingertips are common, most often occurring in children. These injuries can result in macerated tissue, but... . When caring for a patient with a digit amputation, one should consider associated foreign bodies, proximal fractures, ligament... . Standard 3-view x-rays of the affected digit should be performed . Initial management includes assessment of the wound, control of bleeding, and thorough irrigation of the injury without furthe... . Immediate consultation with the hand specialist is needed for all but those with zone I and other minimal injuries. In the Uni... Degloving Injuries Mutilating Hand Injuries Skin and Soft Tissue Injuries Clinical Features Diagnostic Testing Management . Evaluation of a laceration over the extensor tendon includes obtaining visualization of the underlying tendon throughout its e... Disposition Clenched Fist Injuries Infectious Disorders of the Hand General Hand Infections Paronychia Onychomycosis Felon Herpetic Whitlow . Herpetic whitlow is a cutaneous herpes simplex virus (HSV) infection seen on the fingers from contact with oral lesions via se... . Herpetic whitlow is sometimes confused with a paronychia or felon. Special attention should be given to the presence of vesicu... . Diagnosis is made through viral culture or PCR assay of the unroofed lesions . No antiviral therapy is indicated in immunocompetent patients because the disease is generally self-limited, though oral acyc... Purulent Flexor Tenosynovitis . The most common symptom of purulent flexor tenosynovitis is fusiform swelling of the digit, with direct tenderness over the fl... . One should also consider trigger finger (stenosing tenosynovitis), Dupuytren contracture, tendon injury, inflammatory arthriti... . Plain films do not appear to distinguish between tenosynovitis and other general hand infections, though they are used to asse... . Skin contaminants of gram-positive bacteria are typical in these infections, making early use of antibiotics appropriate. Ini... Deep Space Infections . Deep space infections of the volar side of the hand are found under the flexor tendons but above the interosseous muscles in t... . Consider compartment syndrome in patients with exceptional swelling, disproportional pain, and neurovascular compromise . Ultrasound and MRI are more sensitive than CT scan and often are needed to make the diagnosis early in the course of the disea... . The classic infectious organisms include Staphylococcus aureus and Streptococcus spp. Because there has been an increase in gr... Skin and Soft Tissue Disorders Onycholysis High-Pressure Injury Ganglion Cysts Dupuytren Contracture Acknowledgments References 43 - Wrist and Forearm Injuries Foundations Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Carpal Injuries Scaphoid Fractures . Scaphoid fractures often occur after a fall on the outstretched hand, causing hyperextension of the wrist. These injuries are ... . Patients typically report radial-sided wrist pain distal to the radial styloid with decreased range of motion of the wrist an... . Radiographic imaging remains the cornerstone for the evaluation of acute wrist trauma, but radiographic diagnosis of scaphoid ... . To avoid complications associated with delayed diagnosis, such as occult fracture displacement and AVN, patients with suspecte... Lunate fractures . Fractures of the lunate are relatively uncommon. This injury tends to occur in persons with a congenitally short ulna . Patients will experience pain over the dorsum of the wrist, exacerbated by axial loading of the long finger metacarpal. On phy... . In the ED, wrist radiographs are utilized to assess for lunate fractures; however, fractures of the lunate may be difficult to... . To minimize the risk of AVN, clinically suspected lunate fractures should be immobilized due to the possibility of occult luna... Triquetral Fractures . There are two main patterns of triquetral fractures that are observed: triquetral body and dorsal cortical chip fractures. An ... . Patients will experience local tenderness over the dorsal wrist (in the setting of dorsal cortical chips) or volar wrist (avul... . A fracture to the triquetral body is best seen on the AP view. Dorsal triquetral chip fractures are best seen on the standard ... . Treatment of triquetral fractures involves immobilization in a short arm volar splint. Urgent orthopedic referral within 5 to ... Pisiform Fractures . The pisiform is unique because it is the only sesamoid-like carpal bone and attaches to the FCU tendon, articulating on its d... . Fractures of the pisiform usually occur from a fall on the outstretched hand but also may be seen after direct blows to the hy... . Pisiform fractures are poorly seen on routine wrist radiographs and are likely underreported. A reverse (supinated) oblique an... . Nondisplaced fractures of the pisiform generally carry a good prognosis and are treated conservatively, with immobilization in... Hamate Fractures . The hook or hamulus is the most common site of hamate fracture, although articular surfaces and body fractures are also seen . Fracture of the hook usually occurs from a fall on the outstretched hand or from a direct blow to the palm. A fracture to the ... . Hamate body and articular surface fractures are best seen on PA views of the wrist (Fig. 43.17). Standard wrist radiographs ha... . Confirmed hook of hamate fractures should be immobilized in a volar splint that includes the fourth and fifth MCP joints in fl... Trapezium Fractures . There are two main types of trapezium fractures, those involving the body and trapezial ridge . A direct blow to the adducted thumb causes fracture through the body of the trapezium, with transmittal of the force by the ba... . Although trapezium fractures may be seen on the AP view of the wrist, they are typically better visualized on oblique views (F... . Nondisplaced trapezium fractures are treated with immobilization in a short arm thumb spica splint, with orthopedic referral w... Capitate Fractures . The capitate lies in a central position in the distal carpal row and, because of this protected location, it is rarely fractur... . The mechanism generally is a direct blow to the dorsum of the wrist. Fractures may also be seen in association with perilunate... . Fractures usually are visible on the standard PA view of the wrist, although the lateral and oblique views may be helpful in d... . Identified or suspected nondisplaced fractures of the capitate should be managed with immobilization in a short arm thumb spic... Trapezoid Fractures . Trapezoid fractures are rare, usually seen in association with other carpal injuries . The typical mechanism of injury is a direct blow down the long axis of the index metacarpal, which may result in isolated frac... . The fracture may be visible on routine PA views of the wrist; however, oblique views may be superior for visualization of the ... . Confirmed or suspected nondisplaced trapezoid fractures should be immobilized with a short arm thumb spica splint with urgent ... Carpal Instability . The Mayfield classification of carpal instability is comprised of four distinct stages. Each stage represents a sequential int... . Carpal ligamentous injury is caused by wrist hyperextension, ulnar deviation, and intercarpal supination. Patients with these ... . A stage I injury, or scapholunate dissociation, results in a characteristic widening of the scapholunate joint on the PA view,... . Carpal dislocation injuries need emergent orthopedic consultation in the ED for reduction and stabilization. ED management of ... Radiocarpal Dislocation . Radiocarpal dislocations and fracture dislocations are considered extremely rare and are typically associated with high-energ... . Patients are commonly involved in polytrauma scenarios. Dislocations may be volar or dorsal, although ulnar translation of the... . Radiographs of the wrist are typically sufficient to identify radiocarpal dislocations . Emergent reduction of these injuries is paramount because of the extensive soft tissue damage and commonly associated neurovas... Distal Radius and Ulna Injuries Colles Fracture . A Colles fracture refers to a transverse fracture of the distal radial metaphysis, which is dorsally displaced and angulated . Patients classically present with a “dinner fork deformity” on physical examination. The fracture usually is located within 2 ... . The PA view may show extension of the fracture into the radioulnar or radiocarpal joints and the amount of intraarticular step... . Most Colles fractures require ED reduction for restoration of radial length, correction of dorsal angulation (especially when ... Smith Fracture . Smith fracture is a transverse fracture of the metaphysis of the distal radius, with associated volar displacement and angulat... . The typical mechanism of injury involves a direct blow to the dorsum of the wrist or a fall onto the dorsum of the hand result... . The fracture is visible on PA and lateral radiographs of the wrist, but the lateral view best shows the degree of volar displa... . Treatment of this fracture involves closed reduction and immobilization in a splint if the fracture is extra-articular, as di... Barton Fracture . Barton fracture is an oblique intraarticular fracture of the rim of the distal radius, with displacement and dislocation of th... Clinical features . Volar and dorsal rim fractures are visible on PA and lateral wrist radiographs; however, the lateral view best shows the degre... . Treatment of these unstable fractures requires emergent orthopedic consultation for reduction and fixation. Closed reduction m... Hutchinson Fracture . Hutchinson fracture, or chauffeur’s fracture, is an intra-articular fracture of the radial styloid . The mechanism of injury is usually a direct blow or fall resulting in trauma to the radial side of the wrist. The term chauffe... . The fracture is seen best on the PA view of the wrist as a transverse fracture of the radial metaphysis, with extension throug... . Nondisplaced fractures may be immobilized in a sugar tong splint, with the patient given urgent orthopedic referral within 2 t... Distal Radioulnar Joint Disruption . Acute dislocation of the DRUJ can occur as an isolated injury, which is rare, or in association with a fracture to the distal ... . Certain characteristic findings on clinical examination may constitute the only clue to the presence of this injury. The typic... . Diagnosis often is difficult because when the injury occurs in isolation or is not suspected, plain radiographs commonly are r... . Treatment of DRUJ dislocations commonly requires emergent orthopedic consultation for reduction and stabilization. Closed redu... Soft Tissue Injuries of the Wrist Carpal Tunnel and Acute Carpal Tunnel Syndrome Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition De Quervain Disease Foundations Clinical Features Diagnostic Testing Management and Disposition Intersection Syndrome Foundations Clinical Features Diagnostic Testing Management and Disposition Anatomy, Physiology, and Pathophysiology Differential Diagnoses Diagnostic Testing: Radiology Shaft Fractures of Radius and Ulna Foundations Clinical Features Diagnostic Testing Management and Disposition Ulna Shaft Fractures Foundations Clinical Features Diagnostic Testing Management and Disposition Monteggia Fracture Foundations Clinical Features Diagnostic Testing Management and Disposition Galeazzi Fracture Foundations Clinical Features Diagnostic Testing Management and Disposition Essex-Lopresti Lesion Foundations Clinical Features Diagnostic Testing Management and Disposition References 44 - Humerus and Elbow Injuries Background and Importance Anatomy, Physiology, and Pathophysiology General Differential Diagnoses General Diagnostic Testing General Management General Disposition Specific Fractures Shaft of the Humerus . Fractures of the humeral shaft commonly result from a direct blow to the arm, severe twisting, or a fall on an outstretched ha... . Imaging studies should routinely include the shoulder and elbow joints. The humerus is a common site for benign tumors, unicam... . Isolated, closed fractures are treated with a high degree of success. Attempts at fracture reduction and external immobilizati... . Splinting can be done for comfort during patient manipulation but should be limited. Cefazolin (2 g intravenously) is given, a... .5 Radial nerve injury causes wrist drop with loss of the ability to extend the fingers and thumb.6 This nerve injury is most of... . All patients with humeral shaft fractures should be referred to an orthopedic surgeon for further evaluation within 48 hours a... Distal Humerus . Distal humerus fractures that occur proximal to the epicondyles are called supracondylar fractures. This type of fracture is a... Anchor 328 . Extension supracondylar fractures occur as a consequence of a fall on the outstretched hand when the elbow is either fully ext... . Two diagnostic aids in evaluating for possible supracondylar fractures include using the anterior humeral line and evaluation ... . Current treatment recommendations for supracondylar fractures from the American Academy of Orthopedic Surgeons remain based on... Flexion type supracondylar fractures . Flexion-type supracondylar injuries are much less common, with a reported frequency of about 2% of all supracondylar fracture... . Plain films may reveal a simple increase in the anterior angulation of the distal supracondylar fragment or gross displacement... . For flexion-type supracondylar injuries, when the posterior periosteum is torn, the anterior periosteum functions as a tensio... Transcondylar Fractures . Both extension and flexion types of transcondylar fractures have been described based on the position of the elbow when fractu... . Transcondylar (or dicondylar) fractures have a fracture line, either transverse or crescent shaped, that passes through both c... . Transcondylar (or dicondylar) fractures are difficult to treat because the small distal fragment possesses little extra-artic... Intercondylar Fractures . These injuries are rare and generally are seen in adults aged 50 to 70 years. The common mechanism of injury is direct trauma ... . Good-quality anteroposterior and lateral radiographic views are essential in evaluating fracture displacement and comminution... . Treatment of intercondylar fractures is challenging. The goal of treatment is to reestablish articular congruity and alignment... Condylar Fractures . Condylar fractures are rare in adults and typically involve the articular surface and the non-articular portion of the distal... . Diagnosis is usually made on standard anteroposterior and lateral views, although an oblique view also may be helpful. These f... . For condylar fractures, treatment depends on radiographic findings, but controversy exists about the accuracy of these finding... Capitellum and Trochlea Fractures . Fractures of the capitellum and trochlea typically occur together, usually as a result of posterior dislocation of the elbow, ... . For capitellum fractures, a lateral plain film usually shows the fragment lying anterior and proximal to the main portion of t... . Treatment of capitellum and trochlea fractures begins in the ED with a posterior splint, ice packs, elevation, compression, an... Epicondylar Fractures . Most epicondylar fractures involve the medial epicondyle. Medial epicondyle fractures are most common in children and adolesce... . Simple fractures of the medial epicondyle are extra-articular injuries with limited soft tissue injury.18 They generally do n... . For epicondylar fractures, if the fracture fragment is minimally displaced (< 5 mm), treatment with a posterior splint is appr... Olecranon . Fractures of the olecranon commonly occur from a direct blow as a result of a fall, a motor vehicle or motorcycle crash, or an... . Lateral radiographic views provide the most information. In addition to the fracture, the degree of comminution, the extent of... . In olecranon fractures, non-displacement in the 90-degree flexion position indicates that the triceps aponeurosis tendon is ... Radial Head and Neck . Radial head and neck fractures, in general, are produced by an indirect mechanism, typically a fall on an outstretched hand. T... . Radiographic findings range from a subtle disruption of the usual gradual sweep of the radial neck and head surface to an obvi... . Radial head and neck fractures are classified by Manson criteria. Type I nondisplaced fractures are treated symptomatically wi... Dislocations/Subluxations Elbow . The elbow is inherently subject to mechanical instability because of its anatomic structure and dislocations are common. The e... . A radiographic example of posterior elbow dislocation before reduction is provided in Fig. 44.26. The anteroposterior view is ... . Rapid reduction of complete elbow dislocations is important to relieve pain and to prevent circulatory injury or cartilaginous... Radial Head Subluxation . Subluxation of the radial head (or “nursemaids’ elbow”) is a common injury, representing more than 20% of upper extremity inju... . When the history is suggestive of radial head subluxation, radiographs are not indicated and are rarely useful. If there is sw... . Reduction may be attempted in children with typical presentations and is safe even when the classic history is absent. Althoug... Soft Tissue Disorders Epicondylitis . Epicondylitis is a term first introduced to describe an inflammatory process that involves the radiohumeral joint or lateral e... . Radiographic findings may be normal, although with chronicity, calcifications may be present over the lateral epicondyle. Char... . Treatment includes protection, rest, ice, compression, elevation, and analgesics. Initial therapy includes avoidance of the in... Olecranon Bursitis . Olecranon bursitis is commonly caused by repetitive minor trauma, such as leaning on the elbow during work activities. It also... . The most important aspect of evaluation is the differentiation of a septic process from a benign inflammatory one, and this di... . Aspiration is diagnostic and therapeutic because relief of pressure relieves some of the pain. In cases of purulent bursitis, ... Biceps Tendon Rupture . Biceps tendon rupture occurs most commonly in the proximal portion of the long head of the biceps. It is most common in middle... . The patient’s history and physical exam is often diagnostic of such an injury, and radiographs are not revealing and usually n... . All patients require referral to an orthopedist within 72 hours for evaluation for early anatomic repair of complete ruptures.... Acknowledgments References General Clinical Features 45 - Shoulder Injuries Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features History Physical Examination Differential Diagnoses Diagnostic Testing Radiology Specific Injuries Fractures Clavicle . The clavicle accounts for 3% to 5% of all fractures with a 2:1 male to female ratio. It is also the most commonly fractured bo... . The affected extremity is held close to the body as a result of the effect of gravity and the pull of the muscles (pectoralis ... . In patients with direct fall onto lateral shoulder the differential diagnosis includes soft tissue injury (hematoma, contusion... . Clavicle-specific plain radiographs may be required to confirm the presence of a fracture, although most clinically significa... . Principles of initial management for simple fractures include pain control, immobilization primarily for comfort, and proper f... . Most fractures of the clavicle heal uneventfully, and follow-up can be provided by a primary care physician. A sling should b... Scapula . Fractures of the scapula are rare, accounting for approximately 1% of all shoulder fractures and caused by high-energy trauma... . In a conscious patient, the shoulder is held in a position of most comfort, usually with the arm adducted and held close to th... . High energy trauma that can lead to a scapula fracture should also include the following on the differential diagnosis: rib fr... Diagnostic testing . The three-view trauma shoulder series will reveal most scapular fractures, as will careful examination of the scapula on the ... . Presence of a scapular fracture should prompt a thorough search for associated thoracic, intracranial, orthopedic, and neurova... Proximal Humerus . Fractures of the proximal humerus occur primarily in the older population, in whom structural changes (osteoporosis) weaken th... . The affected arm is held close to the body, and movement is restricted by pain. Tenderness, hematoma, ecchymosis, deformity, o... . The differential diagnosis of a proximal humerus fracture includes: glenohumeral dislocation, AC joint separation, rotator cuf... . The three-view trauma series allows for assessment of the number of fracture fragments and degree of displacement or angulati... . Minimally displaced fractures (see Fig. 45.12) constitute up to 80% to 85% of all cases. In these instances, limited displacem... Pediatric Proximal Humeral Fracture . Fractures of the proximal humeral physis and metaphysis are uncommon and account for a small proportion of pediatric fractures... . The patient typically holds the injured arm tightly against the body, using the opposite hand. The area over the proximal hume... . The differential diagnosis for pediatric proximal humeral fractures varies based on age and acuity of the injury. Differential... . Orthogonal radiographs help confirm the diagnosis. Comparison views may be helpful with minimally displaced fractures (Fig. 45... . Fractures of the proximal humeral epiphysis can result in significant permanent injury and disability as the physis accounts f... Dislocations Sternoclavicular . SCJ dislocations are infrequent and account for less than 1% of all dislocations.17 Significant forces are required to disrupt... . Clinical suspicion based on mechanism and exam is the single most important factor in diagnosing these injuries. The injured e... . The differential diagnosis for patients with traumatic SC joint pain include medial clavicle fracture, rib fracture, costochon... . Although diagnosed clinically, sternoclavicular dislocation requires radiological confirmation. Findings on standard anteropos... . Treatment of grade I injuries includes sling immobilization for comfort and primary care follow-up. Immobilization generally ... Acromioclavicular Joint . Injuries of the ACJ occur primarily in young men as a result of MVCs, bicycle accidents, or participation in high impact conta... . Patients should be examined while they are upright, because the supine position can mask ACJ instability, and it is helpful to... . While a lateral blow to the shoulder can cause an AC joint dislocation, other important diagnostic considerations include dist... Diagnostic testing . The recommended projections include routine anteroposterior and axillary lateral view to evaluate for vertical migration of th... . Type I and II injuries should be immobilized in a sling for comfort and to remove stress on injured ligaments. Patients with t... Glenohumeral Dislocations . The GHJ is the most commonly dislocated major joint in the body. Dislocation follows a bimodal age distribution for men, age 2... Anterior Dislocations . Anterior dislocations can result from indirect or direct forces. In younger persons, the injury usually is sustained during at... . The patient presents in severe pain often supporting the dislocated shoulder with the opposite extremity. The lateral edge of ... . Patients presenting with shoulder pain and a full anterior shoulder on examination should be evaluated for glenohumeral disloc... Diagnostic testing . Radiographs including anterior-posterior, trans-scapular Y view, and axillary lateral will confirm the clinical diagnosis and... . Reduction of the dislocation should be accomplished expeditiously, because the incidence of neurovascular complications increa... Posterior Dislocation . Posterior dislocations are uncommon, accounting for fewer than 5% of all glenohumeral dislocations.24,26 The glenoid fossa act... . Early diagnosis is essential to prevent long-term complications. The affected arm is held across the chest in adduction and i... . Posterior glenohumeral subluxation is a much more common event than posterior glenohumeral dislocation and remains an importan... Diagnostic testing . True or standard anteroposterior radiographs can appear deceptively normal with posterior dislocations. Radiographic features ... . Closed reduction may be attempted in the ED with procedural sedation. The technique incorporates internal rotation and lateral... Inferior Glenohumeral Dislocation (Luxatio Erecta) . Luxatio erecta is a rare type (<0.5%) of glenohumeral dislocation in which the superior aspect of the humeral head is forced b... . Clinically, the patient has the arm locked overhead in 110 to 160 degrees of abduction. The elbow usually is flexed, and the f... . Luxatio erectae dislocations are easily mistaken, diagnosed, and treated as subglenoid anterior dislocations, because the radi... Diagnostic testing . Standard radiographs show the superior articular surface inferior to the glenoid fossa (Fig. 45.28). In addition, the humeral ... . Reduction usually can be accomplished by traction/countertraction maneuvers (Fig. 45.29) under procedural sedation. Regional a... Scapulothoracic Dissociation . Scapulothoracic dissociation is a rare and severe injury characterized by complete disruption of the scapulothoracic articulat... . Because most patients present with significant concomitant trauma, the dislocation may not be initially recognized. Massive lo... . Scapulothoracic disassociation is the result of a significant forceful movement and evaluation for concurrent neurovascular in... . Vascular and neurologic injuries can be confirmed through emergent CT angiography and MRI.30 . Identification is a critical step in the management of this injury. Rarely occurring in isolation, these dislocations will typ... Soft Tissue Conditions Impingement Syndrome . Impingement syndrome of the subacromial space occurs across a wide spectrum of the population from the young adult overhead th... . The spectrum of illness is marked by a progression of symptoms. Initially patients report a dull ache around the deltoid area ... . People presenting with vague shoulder pain localizing to lateral shoulder that is worse with movement may have impingement syn... . POCUS can show thickening of the supraspinatus tendon and associated fluid in the subacromial bursa.31 . Initial treatment for impingement syndrome is conservative and consists of rest, simple analgesia using acetaminophen or analg... Rotator Cuff Tears . The rotator cuff acts as a dynamic stabilizer of the GHJ. Its primary function is to hold the humeral head in place throughout... . With acute tears, patients report a sudden tearing sensation in the shoulder followed by severe pain that radiates into the la... . Rotator cuff tears are rarely acute traumatic injuries. In the evaluation of a suspected chronic rotator cuff tear alternative... Diagnostic testing . Plain radiographs likely will be normal in acute or chronic tears and are not generally indicated.34 If obtained, they may sho... . Acute tears should be immobilized in a sling for comfort and the patient referred for orthopedic follow-up within 1 to 2 week... Lesions of the Biceps Muscle Bicipital Tendinitis . Anatomically, the long head of the biceps is subject to the same stresses as those incurred by the rotator cuff within the sub... . On examination, point tenderness can be elicited over the biceps tendon as it passes through the bicipital groove. This is bes... . The differential diagnosis of insidious onset anterior shoulder pain includes proximal biceps tendon tear, rotator cuff tear, ... Diagnostic testing . Radiographs are usually normal and not indicated unless fracture or dislocation is suspected. If obtained, they may show evide... . Emergency treatment consists of rest (sling for comfort), ice, and oral analgesia. Gentle exercises are encouraged as symptoms... Ruptures of the Biceps Tendon . Ruptures of the biceps tendon can be classified into proximal and distal types. Distal ruptures are rare (estimated to have an... . The classic history of an acute rupture is that of a sudden snap or pop, followed by pain and ecchymosis along the arm. Recent... . Alternative differential considerations for anterior shoulder pain after an acute pop include: subluxing bicep tendon, rotator... Diagnostic testing . Radiographic findings usually are unremarkable, and the confirmatory test of choice is MRI. POCUS can be used to identify pres... . The injured arm should be immobilized in a sling with the elbow in 90 degrees of flexion. The patient should be referred to an... Calcific Tendinitis . Shoulder calcific tendinitis affects up to 10% of the population and frequently is encountered in the ED. The condition affect... . The clinical presentation can be divided into silent, subacute, and acute phases based on the physical characteristics of the ... . The clinical presentation of symptomatic calcific tendinopathy can be similar to that of rotator cuff tendinopathy, rotator cu... Diagnostic testing . Radiographs show calcific deposits in the involved tendon (Fig. 45.33). POCUS can identify and effectively localize calcific d... . The acute phase should be treated with a sling for comfort, NSAIDs, and avoidance of offending activities. Refer patients to p... Adhesive Capsulitis . Adhesive capsulitis (“frozen shoulder”) is a specific diagnostic entity characterized by an idiopathic inflammatory reaction w... . Risk factors for developing adhesive capsulitis include female sex, age between 40 and 60 years old, thyroid disease, and diab... . Asymmetric limitations in passive and active range of motion are hallmarks of adhesive capsulitis. Other causes of limited pas... . The diagnosis of adhesive capsulitis is typically made based on a clinical exam and history alone. Radiographs are helpful to ... . The best form of therapy is preventive in nature. Prolonged shoulder immobilization is to be avoided, and early motion encoura... Injection Therapy References 46 - Pelvic Injuries Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Bony and Ligamentous Anatomy Vascular Anatomy Neurologic Anatomy Pathophysiology and Key Patterns of Pelvic Fracture Stable Injuries (Tile Type A) . The normal pelvis is not completely rigid, due to the slight mobility at the sacroiliac joints and symphysis pubis and the inh... . Transverse fractures of the sacrum do not compromise the pelvic ring. Transverse fractures at or below the S4 level are unlike... . These usually occur during athletic activities and are the result of a sudden, forceful muscular contraction or excessive musc... . Stress fractures can occur with vigorous athletic or military training or during the last trimester of pregnancy. The diagnosi... . Pathologic fracture related to neoplasm, Paget disease, or dietary osteomalacia should be included in the differential diagnos... Partially Stable and Unstable Injuries (Tile Types B and C) . Severe anteroposterior compression forces cause disruption at or near the symphysis pubis. The symphysis is normally ≤0.5 cm i... . Lateral compression of the pelvic ring results in varying degrees of internal rotation of the affected hemipelvis. Initially, ... . Vertical shear injuries are the most unstable injuries affecting the pelvic ring and are associated with violent axial loading... . A crucial distinction in considering sacral fractures is that transverse fractures do not involve the pelvic ring, but vertica... Open Pelvic Fractures Penetrating Pelvic Trauma Associated Pelvic Injuries Urologic Injury Neurologic Injury Gynecologic Injury Associated Non-Pelvic Injuries Acetabular Fractures Coccyx Fractures Clinical Features History Physical Examination Deep Venous Thrombosis Differential Diagnosis Diagnostic Testing Radiology Plain Radiography Computed Tomography Evaluation of Hemorrhage Diagnostic Peritoneal Lavage Ultrasound Computed Tomography Management Resuscitation Control of Hemorrhage Stabilizing the Pelvis . The most readily available means to stabilize the pelvis quickly in the ED is a sheet and towel clamps. Wrapping the pelvis ti... . External fixation of the pelvis is performed by orthopedic surgeons to prevent movement at fracture sites and to control bleed... Angiography and Embolization Hemodynamically Unstable Patients With Pelvic and Intra-Abdominal Hemorrhage Disposition References 47 - Femur and Hip Injuries General Information Foundations Anatomy of the Hip and Femur Skeletal Anatomy Musculature Arterial Supply Venous System Nerves Pathophysiology and Key Patterns of Injury Fractures and Trauma of the Femur and Hip Osteoporosis of the Femur . A large percentage of the American population experiences chronic pain from degenerative osteoarthritis of the hip. Disability... Avascular Necrosis Myositis Ossificans Calcific Bursitis and Calcifying Peritendinitis Neoplastic Disease in the Hip History Physical Examination Differential Diagnoses Diagnostic Testing Radiographic Evaluation Occult Hip Fracture Management Traction and Immobilization Open Fracture Care Compartment Syndrome Pain Management Systemic Analgesia Pharmacologic Approaches Femoral Nerve Block Specific Fractures of the Hip and Femur Avulsion Fractures . The incidence of avulsion fractures is increasing as a result of the growth of competitive sports and outdoor activities, espe... . The athlete classically experiences a sudden piercing pain at the site of injury, along with a “snapping” or “popping” sound a... . The differential diagnoses of these avulsion fractures include muscle strain and tears, tendinopathy, and hip dislocations . As depicted in Fig. 47.15, avulsion at the ASIS involves the separation of a thin piece of bone as the sartorius muscle sudden... Proximal Femur Fracture Femoral Neck Fractures . Femoral neck fractures are classified as either nondisplaced or displaced. Between 15% and 20% of all femoral neck fractures a... . On initial evaluation, a patient with a displaced fracture of the femoral neck lies with the limb externally rotated, abducted... . Plain hip radiographs generally confirm the diagnosis of a femoral neck fracture . Treatment of these displaced fractures consists of open reduction and internal fixation (ORIF), hemiarthroplasty, or total hip... . Patients with femoral neck fractures should be admitted for operative repair Intertrochanteric Fractures . The fracture line of intertrochanteric fractures extends between the greater and lesser trochanters of the femur. These injuri... . The strong action of the iliopsoas muscle causes the leg to be shortened and externally rotated . Plain hip radiographs generally confirm the diagnosis of intertrochanteric fractures . A substantial majority of intertrochanteric fractures require internal fixation. Such fixation brings rapid mobilization, decr... . Patients with intertrochanteric fractures should be admitted for operative repair Isolated Fractures of the Greater or Lesser Trochanter . Isolated fractures of the greater or lesser trochanter are rare. They occur in women more often than in men and are the result... . Patients present with hip pain and tenderness over their trochanter . Plain hip radiographs generally confirm the diagnosis of these isolated fractures . Treatment consists of pain control and early mobilization with crutches; weight bearing is allowed as tolerated . Satisfactory outpatient management of this injury is possible because the healing process and prognosis is generally good Subtrochanteric Fractures . Subtrochanteric fractures occur between the lesser trochanter and the proximal 5 cm of the femoral shaft. They may accompany i... . Plain hip radiographs confirm the diagnosis of most subtrochanteric fractures . Definitive management of subtrochanteric fractures is complex. Maintaining limb length and controlling rotation are difficult.... . Patient with subtrochanteric fractures should be admitted for operative repair Femoral Shaft Fractures . Femoral shaft fractures are common injuries in young adults after high-energy trauma. As is the case with other femoral corti... . Patients often arrive with the injured extremity immobilized by traction devices, which should be removed while immobilization... . Plain hip radiographs including full length views of the femur confirm most femoral shaft fractures . Internal fixation with intramedullary rods has been demonstrated to shorten both hospitalization and total disability time aft... . Patients with femoral shaft fractures should be admitted for operative repair Stress Fractures . Femoral neck stress fractures or reactions occur when normal bone is subjected repeatedly to submaximal forces. This recurring... . The symptoms of a stress fracture of the femoral neck are often subtle and can be mistaken for a muscle strain or an overuse i... . Radiographs are helpful if they demonstrate a fracture, but findings are often negative until 10 to 14 days after the symptoms... . Treatment of stress fractures of the femoral neck is based on involvement of the compressive or tensile aspect. Compressive-s... . Urgent orthopedic consultation for decision of operative versus nonoperative treatment is recommended for these types of stres... Dislocations and Fracture-Dislocations of the Hip and Femur Hip Dislocations . Dislocations and fracture-dislocations of the hip are true orthopedic emergencies. The hip joint possesses impressive inheren... . The position of the injured extremity might provide valuable clues in the evaluation of a hip dislocation. A patient with a po... . Radiologic investigation begins with an anteroposterior view of the pelvis. This view alone will identify the majority of hip ... . Hip dislocations constitute a true orthopedic emergency, and reduction should be performed within 6 hours. The incidence of AV... . Most patients with a native hip dislocation will require admission to the hospital and urgent orthopedic referral for serial e... Fracture-Dislocation of the Femoral Head . Hip dislocations can be associated with fractures of the femoral head (Fig. 47.29A). Femoral head fracture occurs in 35% to 55... . When a femoral head fracture and hip dislocation coexist, patients assume the position typical for the dislocation. Hip mobili... . Radiographs should be evaluated for any femoral head fracture in patients with hip dislocations. Evidence for fracture of the ... . In most cases, satisfactory results can be obtained with closed reduction (see Fig. 47.29B). Several experts recommend obtaini... . Patient with fracture-dislocation of the femoral head should be admitted for operative management Dislocation of Hip Prosthetics . An increasing number of patients have undergone hip arthroplasty. In addition to those procedures performed for treatment of f... . Most patients will present with inability to bear weight with associated hip or groin pain. The affected leg with be externall... . Radiologic investigation begins with an anteroposterior view of the pelvis. See the Hip Dislocation section in this chapter fo... . Reduction techniques for prosthetic hip dislocations are identical to those described earlier but are not as time dependent as... . Consultation with an orthopedic surgeon is recommended for development of a long-term treatment plan for the patient as chron... Soft Tissue Injuries Muscular Injuries . Strenuous exercise by a poorly conditioned person, sudden exertion, and direct trauma all can injure soft tissues. Cold temper... . Partial tears are reversible injuries that are aggravated by movement or tension. Mild spasm, swelling, ecchymosis, and tender... . Differential diagnoses of these soft tissue injuries include muscle strain, partial and complete muscle tears, ligamentous or ... . In the ED, plain radiographs can be obtained to exclude any fractures. Bedside ultrasound is also helpful in evaluating for pa... . Initial management of incomplete tears traditionally includes the local application of ice for the first 48 hours, followed by... . Any patient with significant injury should be referred for physical therapy. A complete muscle tear requires follow-up care w... Tendon Injuries . Clinically, tendinopathies tend to have a more insidious onset than that typical for muscle strains. These strains occur at th... . Local pain over the tendon, exacerbated by stretching of the tendon, is a common physical examination finding. Pain may radiat... . Differential diagnoses of these tendon injuries include avulsion fractures, partial or complete tears of the muscles or tendon... . Ultrasound imaging may lend additional diagnostic information. MRI can provide a definitive diagnosis but is not indicated in ... . Treatment of a tendon strain is similar to that for other soft tissue injuries. The use of crutches with weight bearing as tol... . Most patients will require follow up with an orthopedic or sports medicine specialist within a week Osteitis Pubis . Osteitis pubis is characterized by pubic symphysis pain and joint disruption and is most common in distance runners and soccer... . Clinically, patients have groin pain of insidious onset, with most reporting pain at the symphysis and adductor muscles. Pain ... . Osteitis pubis has been associated with spontaneous cases of pubic symphysis osteomyelitis and should be considered in the dif... . Plain radiographs show widening of the symphysis, irregular contour of the articular surfaces, or periarticular sclerosis (a d... . Treatment is conservative since in most cases the process is self-limited. Patients benefit from activity modification, weari... . Owing to the length of healing associated with these injuries, follow-up care should be arranged at the time of initial injur... Vascular Injuries . Hip dislocations and femoral fractures may have associated arterial injury. The vessel can be partially lacerated, dissected, ... . Patients may have decreased pulses, poor capillary refill, cold extremities, paresthesias and increased pain . The differential diagnoses of these vascular injuries include arterial thrombus, arterial dissection, and complete or partial ... . Ultrasound or CT angiogram are indicated for evaluating the vasculature . Orthopedic or vascular surgery consultation is recommended if any partial or complete vascular tear is found. Fracture reducti... . Most patients with these vascular injuries will require admission for their femoral fracture repair Neurologic Injuries . Peripheral nerve injuries can be caused by trauma, external compression, infection, and degenerative disease. In trauma, nerve... . Patients present with sensory loss or motor weakness. Mild cases may present with paresthesias . No specific testing in the emergency department is indicated other than a focused physical examination, though MRI may be able... . Treatment of neurovascular compromise from a hip dislocation or a displaced femoral fracture consists of immediate reduction t... . Most traumatic nerve injuries will be observed in the hospital or require urgent orthopedic consultation. Neurapraxia from com... References 48 - Knee and Lower Leg Injuries Knee Injuries—Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Femur The Tibia Cruciate Ligaments (ACL and PCL) Collateral Ligaments (MCL and LCL) Knee Compartments Fabella Popliteal Fossa Popliteal Artery Tibial Nerve Extensor Mechanism Meniscus The Iliotibial band The Popliteus Bursae Knee Injuries—Clinical Features Physical Examination Knee Injuries—Differential Diagnoses Dislocation Effusion Anterior Knee Pain Medial and Lateral Pain Posterior Knee Pain Knee Injuries—EXAMINATION MANEUVERS Anterior Drawer/Lachman Test Posterior Drawer Test Posterior Sag Sign Test Collateral Ligament Stress Test Assessing for Meniscal Tears McMurray Test Apley Test Knee Injuries—Diagnostic Testing Radiologic Evaluation Vascular Imaging Arthroscopy Joint Injection Arthrocentesis Specific Knee Injuries Knee Dislocations—Foundations Knee Dislocations—Clinical Features Knee Dislocations—Diagnostic Testing Knee Dislocations—Management and Disposition Distal Femur Fractures—Foundations Distal Femur Fractures—Clinical Features Distal Femur Fracture—Diagnostic Testing Distal Femur Fractures—Management and Disposition Tibial Plateau Fractures—Foundations Tibial Plateau Fractures—Clinical Features Tibial Plateau Fractures—Diagnostic Testing Tibial Plateau Fractures—Management and Disposition Tibial Spine Fractures—Clinical Features Tibial Spine Fractures—Diagnostic Testing Tibial Spine Fractures—Management and Disposition Osteochondritis Dissecans—Foundations Osteochondritis Dissecans—Clinical Features Osteochondritis Dissecans—Diagnostic Testing Patellar Fractures—Foundations Patellar Fractures—Clinical Features Patellar Fractures—Diagnostic Testing Patellar Fractures—Management and Disposition Patellar Dislocation—Foundations Patellar Dislocation—Clinical Features Patellar Dislocation—Diagnostic Testing Patellar Dislocation—Management and Disposition Cruciate and Collateral Ligament Injuries—Foundations Meniscal Injuries—Foundations Meniscal Injuries—Clinical Features Meniscal Injuries—Diagnostic Testing Meniscal Injuries—Management and Disposition Overuse Syndromes Patellofemoral Pain Syndrome—Foundations Patellofemoral Pain Syndrome—Clinical Features Patellofemoral Pain Syndrome—Diagnostic Testing Iliotibial Band Syndrome—Foundations Iliotibial Band Syndrome—Clinical Features Iliotibial Band Syndrome—Diagnostic Testing Iliotibial Band Syndrome—Management and Disposition Patellar Tendinopathy—Foundations Patellar Tendinopathy—Clinical Features Patellar Tendinopathy—Diagnostic Testing Patellar Tendinopathy—Management and Disposition Plica Syndrome—Foundations Plica Syndrome—Clinical Presentation Plica Syndrome—Diagnostic Testing Plica Syndrome—Management and Disposition Popliteus Tendinopathy—Foundations Popliteus Tendinopathy—Clinical Presentation Popliteus Tendinopathy—Diagnostic Testing Popliteus Tendinopathy—Management and Disposition Bursitis—Foundations Bursitis—Clinical Features Bursitis—Diagnostic Testing Bursitis—Management and Disposition ARTHRITIS Osteoarthritis—Foundations Osteoarthritis—Clinical Features Osteoarthritis—Diagnostic Testing Osteoarthritis—Management and Disposition Septic Arthritis—Foundations Septic Arthritis—Clinical Features Septic Arthritis—Diagnostic Testing Septic Arthritis—Management and Disposition BAKER CYST Baker Cyst—Foundations Baker Cyst—Clinical Features Baker Cyst—Diagnostic Testing Baker Cyst—Management and Disposition Leg Foundations Anatomy, Physiology, Pathophysiology Tibia and Fibula Vascular Supply Fascial Compartments Leg Injuries Differential Diagnoses Specific Leg Injuries Proximal Extra-articular Tibial Fractures Subcondylar Tibial Fractures—Foundations Subcondylar Tibial Fractures—Clinical Features Subcondylar Tibial Fractures—Diagnostic Testing Subcondylar Tibial Fractures—Management and Disposition Tibial Tubercle Fractures—Foundations Tibial Tubercle Fractures—Clinical Features Tibial Tubercle Fractures—Diagnostic Testing Tibial Tubercle Fractures—Management and Disposition Tibial Shaft Fractures—Foundations Tibial Shaft Fractures—Clinical Features Tibial Shaft Fractures—Diagnostic Testing Tibial Shaft Fractures—Management and Disposition Proximal Fibula Fractures—Foundations Proximal Fibula Fractures—Clinical Features Proximal Fibula Fractures—Diagnostic Testing Proximal Fibula Fractures—Management and Disposition Proximal Tibiofibular Joint Dislocations—Foundations Proximal Tibiofibular Joint Dislocations—Clinical Features Proximal Tibiofibular Joint Dislocations—Diagnostic Testing Proximal Tibiofibular Joint Dislocations—Management and Disposition Stress Fractures—Foundations Stress Fractures—Clinical Features Stress Fractures—Diagnostic Testing Stress Fractures—Management and Disposition Medial Tibial Stress Syndrome—Foundations Medial Tibial Stress Syndrome—Clinical Features Medial Tibial Stress Syndrome—Diagnostic Testing Medial Tibial Stress Syndrome—Disposition and Management Compartment Syndrome Soft Tissue Injuries Involving the Lower Leg . The gastrocnemius is composed of two distinct muscle bellies, the medial and lateral heads. The medial head is usually slightl... . Patients with gastrocnemius injury typically present to the ED with point tenderness and swelling in the calf. If the gastrocn... . Venous duplex should be performed to rule out DVT and may help to differentiate between these conditions. Soft tissue defects ... . A small partial rupture of the medial head of the gastrocnemius can be treated with rest and non–weight bearing for several da... . Foreign bodies such as plant matter (e.g., thorns), glass, and metallic objects are commonly encountered in the leg. Missed re... References 49 - Ankle and Foot Injuries Background and Importance Anatomy Physiology and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Radiology Other Imaging Techniques Ankle Fractures and Dislocations General Considerations Unimalleolar Fractures Lateral Malleolar Fractures Medial Malleolar Fractures Posterior Malleolar Fractures Bimalleolar Fractures Trimalleolar Fractures Open Fractures Pilon Fractures Clinical Features Differential Diagnoses Diagnostic Testing Management Dislocations Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Ligamentous Injuries Foundations Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Tendon Injuries Differential Diagnoses Achilles Tendon Rupture . Achilles tendon rupture is most common in middle-aged men, and its causes are multifactorial. This condition is easily misdia... . Achilles tendon rupture results from direct trauma or indirectly transmitted forces, including sudden unexpected dorsiflexion,... . The diagnosis of Achilles tendon rupture is primarily clinical. Patients usually describe a sudden onset of pain at the back o... . A lack of consensus exists between operative and nonoperative management in the treatment of Achilles tendon rupture.14 Surgic... Peroneal Tendon Dislocation or Rupture . The peroneal muscles are the primary evertors and pronators of the foot and also participate in plantar flexion. The peroneus ... . Plain radiographs of the ankle may show the peroneal “fleck” sign, which can be confused for a simple avulsion fracture off th... . Peroneal tendon rupture, subluxation or dislocation should be clinically (see Table 49.2) or radiologically assessed and the p... Tibialis Posterior Tendon Rupture . The tibialis posterior is primarily responsible for plantar flexion and inversion along the subtalar joint. Its tendon uses th... . The diagnosis is generally made on a clinical basis. Plain radiographic films can exclude other bony pathology. Ultrasound can... . Urgent outpatient orthopedic consultation within a week is indicated for tibialis posterior tendon ruptures because surgical r... Other Tendon Injuries Foot Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Specific Pathologic Conditions Hindfoot Injuries Differential Diagnoses Talar Fractures . The talus is a complex structure with articular cartilage covering 60% of its surface. It has no muscular attachments and is h... . Talar fractures range from obvious fractures to subtle injuries requiring special imaging for diagnosis. There is generally a ... . Talar neck fractures account for 50% of all talus fractures. With the exception of dorsal avulsion fractures, talar neck fract... . Talar head fractures make up 10% of all talar fractures. Their mechanism is an axial compressive force applied on a plantar-f... . Major talar body fractures are uncommon and usually result from falls with axial compression of the talus, between the tibial ... . When talar fractures are clinically suspected, initial imaging should include standard foot and ankle radiographs. This series... . Talar neck fractures have a significant risk of long-term morbidity and require precise reduction. Type 1 fractures, which ar... . With the exception of minor dorsal avulsion fractures, all talar fractures should be managed by orthopedics. In the case of ma... Osteochondral Lesions . Osteochondral lesions of the talar dome warrant special mention. These talar body injuries are defects of the articular cartil... . An osteochondral lesion should be considered in any patient with an acute ligamentous ankle injury with a joint effusion. Most... . Differential diagnoses of osteochondral lesions include those items outlined in Box 49.2 . Plain radiography can identify significant osteochondral defects, although CT is useful in identifying occult osteochondral le... . When an acute osteochondral lesion is confirmed or suspected, patients are best managed with outpatient orthopedic or sports m... Subtalar Dislocations . Subtalar dislocation, also called peritalar dislocation, is the simultaneous disruption of the talocalcaneal and talonavicular... . Obvious deformity is typically present, often with skin tension on the side opposite the direction of dislocation. Neurovascul... . Although standard foot radiographic views are diagnostic, properly positioning the patient for them may be difficult. The sing... . Subtalar dislocations require emergent reduction. Most closed subtalar dislocations can be treated with closed reduction with ... . Emergent orthopedic consultation is indicated for subtalar dislocations Pantalar Dislocation Calcaneal Fractures . The calcaneus is the largest and most commonly fractured tarsal bone. It articulates superiorly with the talus (forming the su... . These are more serious and more common, accounting for up to 75% of calcaneal fractures. Classification systems used to descri... . These include fractures of the anterior process, sustentaculum tali, lateral and medial calcaneal processes, peroneal tubercle... . Physical examination reveals pain, swelling, and tenderness over the heel. Weightbearing on the hindfoot is usually impossible... . Please refer to Table 49.3 for differential diagnoses of extraarticular calcaneal fractures . In the case of a suspected calcaneus fracture, initial radiographic imaging should include a foot series with the addition of ... . Emergency evaluation includes careful assessment for associated injuries, particularly vertebral fractures. Adequate pain cont... . All patients with intraarticular calcaneal fractures, or fractures that compromise overlying skin or soft tissue, warrant orth... Midtarsal Joint Injuries . The midtarsal joint (Chopart joint) is comprised of the talonavicular and calcaneocuboid joints. Injury in this area is uncomm... . Refer to Table 49.3 for a list of differential diagnoses of midtarsal joint injuries . Although standard radiographs are often abnormal, the diagnosis frequently is overlooked or delayed, with symptoms ascribed to... . Nondisplaced injuries may heal with casting, but operative fixation is often required. Orthopedic consultation in the outpatie... Nontraumatic Hindfoot Pain Clinical Features Differential Diagnoses Diagnostic Testing Management Midfoot Injuries Differential Diagnoses Navicular Fractures . The navicular forms the supporting structure for the medial arch of the foot and bears most of the load within the tarsal comp... . Navicular fractures are classified as dorsal avulsion fractures, tuberosity fractures, and body fractures. Fractures of the bo... . Navicular fractures cause localized tenderness over the dorsal and medial aspects of the midfoot. The navicular tuberosity is ... . See Table 49.3. The os tibiale externum is an accessory bone present in approximately 10% of the population and it is not unco... . Although standard foot radiographs usually identify navicular fractures, advanced imaging with CT may be necessary. This is pa... . Nondisplaced dorsal avulsion fractures can be treated symptomatically. Displaced dorsal avulsion fractures, or those involving... . The majority of navicular fractures are suitable for outpatient orthopedic referral. Nondisplaced dorsal avulsion fractures in... Cuboid Fractures Cuneiform Fractures Dislocations of the Navicular, Cuboid, and Cuneiforms Lisfranc (Tarsometatarsal) Fractures and Dislocations . Lisfranc injuries refer to any fracture, dislocation, or ligamentous injury at the tarsometatarsal joint (Lisfranc joint). In ... . Lisfranc injuries carry a significant risk of long-term disability resulting from arthritis, instability, foot deformity, and... . The diagnosis of Lisfranc injury can be a challenge, particularly in the case of low-energy, isolated ligamentous injuries. C... . See Table 49.3 for differential diagnoses of Lisfranc (tarsometatarsal) fractures and dislocations . Standard radiographic views of the foot are the initial investigation of choice for suspected Lisfranc injuries. However, plai... . High-energy Lisfranc injuries or ligamentous injuries with displacement, either on standard radiographs or stress imaging, ar... . All proven or suspected Lisfranc injuries should be managed with orthopedic consultation. Delayed treatment or misdiagnosis ca... Nontraumatic Midfoot Pain Forefoot Injuries Differential Diagnoses Diagnostic Testing Metatarsal Fractures . Metatarsal fractures are common and account for one-third of foot fractures. Management depends both on the specific location... . The first metatarsal is the largest and strongest of the metatarsal bones and is rarely fractured. Injury to the first metatar... . Middle metatarsal fractures often result from crush injuries but can occur from indirect trauma such as in twisting injuries. ... . Patients will present with pain, tenderness, and swelling in the midfoot and usually inability to bear weight . See Table 49.3 for a list of differential diagnoses of metatarsal fractures . Plain radiographs are generally adequate for diagnosis of acute fractures. CT imaging may better delineate the diagnosis, part... . The middle metatarsals are inherently stable with extensive soft tissue support from adjacent metatarsals. Nondisplaced fractu... . The fifth metatarsal is the most commonly fractured metatarsal. Fractures of the fifth metatarsal are divided anatomically int... . Fractures of the shaft of the 5th metatarsal are often referred to as “dancers’ fractures.” These injuries result from an inve... . Fractures in zone 1 of the fifth metatarsal base occur from avulsion of the tuberosity by the lateral band of the plantar apon... . See Box 49.2 and Table 49.3 for a list of differential diagnoses of fifth metatarsal fractures . Plain radiographs are generally adequate for diagnosis of acute fractures of the fifth metatarsal . Historically, tuberosity fractures involving more than 30% of the articular surface or with more than 2 mm of displacement wer... Phalangeal Fractures . Phalangeal fractures are the most common forefoot fracture. The proximal phalanges are more commonly fractured than middle or ... . Although phalangeal fractures generally are considered minor injuries, they can lead to disabling sequelae. Patients present w... . See Table 49.3 listing differential diagnoses for phalangeal fractures . As with metatarsal fractures, carefully assessed standard radiographic views are sufficient to demonstrate phalangeal fracture... . Most phalangeal fractures are easily managed and heal well. Large (greater than 50% of the nail bed) and symptomatic subungual... . In general, primary care follow-up is appropriate for phalangeal fractures. If displacement persists or causes cosmetic or fu... Sesamoid Fractures Metatarsophalangeal Dislocations . MTP joint dislocations can occur in any joint and in any direction. First MTP joint dislocations require large forces and usua... . First MTP joint dislocations usually are obvious because the toe is angled upward, with dorsal and proximal displacement of th... . See Table 49.3 describing differential diagnoses of metatarsophalangeal dislocations . Dislocations of the MTP joint are well-visualized on standard radiographic views of the foot. Radiographs should be scrutiniz... . Most MTP joint dislocations, particularly of the lesser toes, are easily reduced with longitudinal traction. Analgesia or loca... . Most MTP joint dislocations can be managed without orthopedic consultation. If crepitus or obvious instability is present, or ... Interphalangeal Joint Dislocations Nontraumatic Forefoot Pain . The forefoot is the site for a myriad of painful problems. Bunions, painful bursae, blisters, corns, calluses, hammertoes, and... . Refer to Table 49.3 for differential diagnoses of nontraumatic forefoot pain . Although the vast majority of nontraumatic forefoot pain is diagnosed clinically, plain radiography may be useful to rule out ... . Most diagnoses of nontraumatic forefoot pain may be managed on a nonurgent basis by a podiatrist or primary care physician. Mo... Special Considerations Complex Regional Pain Syndrome Stress Fractures Foundations and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Tendon Injuries Compartment Syndrome of the Foot and Ankle Foundations Clinical Features Differential Diagnoses Diagnostic Testing: Special Procedures Management and Disposition References 50 - Wound Management Principles Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features History Physical Examination Differential Diagnoses Diagnostic Testing Management Anesthesia Anesthetic Agents Allergy Skin Preparation Wound Preparation Debridement Wound Cleansing Irrigation Wound Closure Decision-Making Wound Tension Suture Technique . Wound closure with simple interrupted sutures is the most common method of laceration repair in the ED and the majority of wou... . The needle is placed to one side of the laceration margin and enters the skin at approximately 90 degrees. To pass the needle ... . Placing cutaneous sutures in wounds under tension can lead to ischemia of the wound margin and an unsightly scar. Proper place... .. Placement of buried sutures differs from traditional suturing because of the need to bury the knot deep to the skin. Failure ... . In contrast to small lacerations elsewhere on the body, most scalp lacerations require repair because of the propensity to ble... . Anesthesia with epinephrine is recommended to help control bleeding. Hair removal is necessary only if the hair makes closure ... . Most commonly seen in elders and the chronically ill, skin tears can be a treatment dilemma for emergency clinicians. These te... . Vertical mattress sutures improve wound edge eversion. They are also used to close gaping wounds and deep lacerations that may... . A vertical mattress suture technique is a combination of deep and superficial components. The needle is introduced at a 90-de... . Horizontal mattress sutures are useful to help disperse excess skin tension and to evert wound edges. The scalp, which has min... . The initial step is to pass the needle as for a simple interrupted stitch (Fig. 50.4). On exiting the skin, however, the needl... . Redundant tissue may be left on one side of the repair as the closure nears completion, especially with curvilinear laceration... . The laceration repair begins in a traditional manner and continues to approximately the final 1 cm of the wound (Fig. 50.5). A... . Jagged and triangular wounds create corners that can be difficult to repair. The clinician must avoid placing the suture direc... . The needle is introduced percutaneously through the non-flap side of the wound a few millimeters from the corner of the wound... . The V-Y closure is indicated for the repair of V-shaped wounds with tissue loss or with nonviable margins that must be trimm... . Nonviable tissue is trimmed with fine iris scissors (Fig. 50.7). The long V-shaped portion of the wound is sutured with simpl... Materials . The ideal suture is inert to metabolism, resistant to infection and inflammatory reactions, has great tensile strength, does n... . Surgical needles are available in a variety of sizes and shapes with myriad other characteristics. Cutting needles may be reve... . Tape closure may be superior to closure with sutures and staples if applied in the appropriate circumstances. In general, the ... . Staples offer several advantages over sutures. Monofilament stainless steel staples offer less risk of infection than even the... . European and Canadian physicians have used tissue adhesives (butyl-2-cyanoacrylates) for many years. In 1998, octyl-2-cyan... Antibiotic Prophylaxis . Antibiotic prophylaxis with an antibiotic covering skin flora (e.g., cefazolin IV, cephalexin PO) is recommended for patients ... . Wounds that involve joints or open fractures require prophylactic antibiotics. Prospective randomized controlled studies have ... . Antibiotics are indicated for through-and-through intraoral lacerations, cat bites, some dog bites, some human bites, and so... . Antibiotic prophylaxis is required for patients with cat bites, especially bites to the hand. These bites tend to be deep punc... . Antibiotic prophylaxis for dog bites is more controversial. The infection rate has been reported as 6% to 16% for patients not... . In addition to the previous bite wound recommendations, antibiotic prophylaxis of injuries to the metacarpophalangeal joints i... . Lacerations of the oral mucosa involve bacteria-rich oral secretions and may become infected slightly more often (6% to 12%) ... . Puncture wounds of the foot are seen frequently in the ED. These wounds are often caused by common carpentry nails, although o... Drains, Dressings, and Immobilization . Drains have no role in ED wound care. In general, drains are placed when a collection of fluid exists or may develop. The pres... . Various dressing materials are available. The microenvironment created by a dressing affects the biology of healing. The optim... . Wounds in proximity to joints must be immobilized as part of routine care. Splinting the injured body part places the injury a... Disposition Wound Care Instructions Tetanus Immunization References 51 - Foreign Bodies Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Specific Disorders Eye Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Ear Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Nose Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Airway Foundations . Children and the elderly are at high risk for foreign body aspiration. Most airway foreign body patients are younger than 9 ye... . Foreign bodies can be located as proximally as the oropharynx, with retained objects having been found in the palatal and phar... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Gastrointestinal Tract Foundations Pharynx and Esophagus Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Stomach and Bowel Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Rectum Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Genitourinary Tract Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Soft Tissues Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 52 - Mammalian Bites Foundations Background and Importance Dog Bites Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Capnocytophaga canimorsus Diagnostic Testing Differential Diagnoses Management . The value of prophylactic antibiotics given for mammalian bites is secondary to the value of vigilant cleaning, debridement, a... Disposition Cat Bites Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Pasteurella multocida Differential Diagnoses Diagnostic Testing Management Disposition Other Mammals Monkeys Foundations . Monkey bites are rare in the United States, occurring primarily in laboratory workers involved in biomedical research. Monkey ... . Monkey bites may present with superficial bruising, puncture marks, or small, grouped lacerations. Superficial and deep soft t... . B virus disease in humans has an incubation period as short as 2 days but more commonly 2 to 5 weeks. The disease often starts... . The bacteria isolated from infected monkey bites is similar to that from infected human bites, with a predominance of Staphylo... . While under studied, monkey bites may also have a risk profile for bacterial infection similar to human bites and should recei... . The majority of monkey bites can be safely discharged home from the emergency department (ED) following local wound care, appr... Rodents Foundations . As with monkey bites, laboratory workers are frequent rodent bite victims because these animals are commonly used in biomedica... . Infection and systemic illness, “rat bite fever,” is caused by bacteria from Streptobacillus moniliformis or Spirillum minus, ... . Disease transmission may occur by bite, scratch, handling a rat, or by ingestion of contaminated food or water. The incubation... Differential diagnoses . Rodent bites are at low risk for local wound infection and require only appropriate wound care without antibiotic prophylaxis.... . The vast majority of rodent bites can be safely discharged home from the ED with wound care instructions and outpatient follow... Uncommon Animal Bites Ferrets Domestic Herbivores Sheep, Cattle, and Pigs Horses Camels Wild Animals Bears Wild Cats Coyotes and Wolves Management Human Bites Foundations . Human bites tend to occur during summer months, typically on weekends, and most often involve acts of aggression. Sporting eve... . Human bites can be divided into two categories: occlusive bites and clenched-fist injuries (CFIs). Occlusive bites are those ... . Fight bites (clenched-fist injury). Acute CFIs typically present as an innocuous appearing 3- to 8-mm laceration over the d... . Human occlusive bites generally cause less tearing and crush injury than dog bites, and do not penetrate soft tissues as readi... . Human bites have resulted in transmission of tetanus, syphilis, actinomycosis, and herpes. Herpetic whitlow, an infection of t... . Due to their high incidence of deep structure injury and the possibility of retained tooth fragments, we advise obtaining radi... . Treatment should focus on the mechanism of the bite (occlusive or CFI), the health of the bite victim including medical histor... Prophylactic Antibiotics Disposition References 53 - Venomous Animal Injuries Foundations Venom Delivery Venomous Reptiles Snakes Classification and Characteristics Anatomy and Identification Other Reptiles Pathophysiology and Toxins Venom Delivery Clinical Features Crotalids (Pit Vipers) Coral Snakes Infection Differential Diagnoses Diagnostic Testing Management Out-of-Hospital Care Emergency Department Care Patient History Patient Examination Initial Medical Care Pit Viper Envenomation Classification Antivenom Dosage and Precautions Coral and Exotic Snakes Wound Care Serum Sickness Heloderma Envenomation Disposition Venomous Arthropods Foundations Hymenoptera Spiders and Scorpions Black Widow Spider Brown Recluse Spider Scorpions Clinical Features Hymenoptera Africanized Bees Fire Ants Black Widow Spider Brown Recluse Spider Scorpions Differential Diagnoses Hymenoptera Black Widow Spider Brown Recluse Spider Scorpions Diagnostic Testing Hymenoptera Black Widow Spider Brown Recluse Spider Scorpions Management Prehospital Care Hymenoptera Black Widow Spider Brown Recluse Spider Scorpions Emergency Department Care Hymenoptera Black Widow Spider Latrodectus Antivenom Brown Recluse Spider Scorpions Disposition Hymenoptera Black Widow Spider Brown Recluse Spider Scorpions Other Arthropods Venomous Marine Animals Foundations Pathophysiology and Venom Delivery Bites Nematocyst Toxicity Clinical Features Stings Sea Urchins Cone Shells Stingrays Bony Fishes Differential Diagnoses Diagnostic Testing Management Bites Nematocysts Stings Disposition References 54 - Thermal Injuries Background and Importance Anatomy, Physiology, and Pathophysiology Pathophysiology of Burns Cutaneous Injury Clinical Features Classification and Diagnosis of Burns Depth Size Inhalation Injury Differential Diagnoses Diagnostic Testing Management Initial First Aid Airway Management Breathing Management Circulation Management and Fluid Resuscitation Escharotomy Local Wound Therapies Pain Management Disposition References 55 - Chemical Injuries General Approach to a Hazmat Event Foundations Background and Importance Community Preparedness and HazMat Response Contingency Plan Anatomy, Physiology, and Pathophysiology Clinical Features and Differential Diagnoses Diagnostic Testing Management Disposition Ocular Injuries Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Specific Toxins Hydrofluoric Acid Foundations . Hydrofluoric acid is an acidic aqueous solution made from fluorine. It has a variety of industrial indications, including glas... . Absorption of hydrofluoric acid can occur upon exposure to the lung, skin, and eyes. In a 20-year review of all hydrofluoric ... Clinical Features Inhalational Exposure Gastrointestinal Exposure Ocular Exposure Dermal Exposure Differential Diagnoses Diagnostic Testing Management Infiltration Therapy . Infiltrative therapy is necessary for treatment of deep, painful hydrofluoric acid burns. Calcium gluconate is the agent of ch... . Patients with pain refractory to local or subcutaneous calcium administration may benefit from regional anesthesia, either int... Respiratory Exposures Ocular Exposures Systemic Toxicity Disposition Formic Acid Foundations . Formic acid is a caustic organic acid used in rubber, paper, tanning, agricultural, and electroplating industries. It has also... . Formic acid causes cutaneous injury by inducing a coagulative necrosis Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Anhydrous Ammonia Foundation . Anhydrous ammonia is a colorless, pungent gas used extensively as a fertilizer in agriculture. It can also be used to manufact... . Anhydrous ammonia is generally stored at an extremely low temperature (−33°C). Consequently, exposure to liquid at this temper... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Cement Phenol and Derivatives Foundations . Phenols are used industrially as starting materials for many organic polymers and plastics. They are widely used in the agricu... . Phenol (carbolic acid) is an aromatic acidic alcohol with a characteristic odor. The concentration of phenol is inversely rela... . When the skin comes in contact with a phenol, treatment should be instituted immediately. The exposed area should be irrigated... Differential Diagnoses Diagnostic Testing Management Treatment of Systemic Toxicity Disposition Phosphorus Foundations . Phosphorus is a nonmetallic element that exists in three forms: elemental, white (yellow), and red. White phosphorus (also kno... . The autoignition temperature (the temperature at which spontaneous combustion can occur) is 30°C (86°F). When white phosphorus... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Nitrates and Nitrites Foundations . Both nitrates (NO3−) and nitrites (NO2−) are abundant in rural and industrial settings. Both sodium nitrate and sodium nitrite... . Reduced hemoglobin contains four heme groups, each with a ferrous (Fe2+) ion. Methemoglobinemia results when the ferrous ion b... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Hydrocarbons Foundations . Hydrocarbons are a heterogeneous group of organic compounds that are derived from carbon and hydrogen molecules. They are foun... . The toxicity from hydrocarbons can affect many different organs, but the lungs are the most commonly affected. The toxicity of... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Tar Foundations . There are two types of hot tar: coal tar pitches and petroleum-derived asphalts. Both products are heated to maintain a liqui... Clinical Features Management Disposition Elemental Metals Chromium Miscellaneous Chlorine, Chloramine, Phosgene, Nitrogen Oxide and Phosphide . Chlorine and phosgene gases were used in World War I as part of chemical warfare. Today, exposure to chlorine exposures can re... . Chlorine is a heavy greenish-yellow gas or liquid with a characteristic odor. The combination of bleach (sodium hypochlorite)... . Mild exposure to chlorine or chloramine may simply cause mucosal membrane irritation, whereas more severe exposure will induce... . The first step in treating an exposure to chlorine, chloramine, or phosgene gas is removal of the individual from the environm... . Phosgene, phosphene, NO2, nickel carbonyl, diborane, as well as zinc-based smoke bombs can cause delayed-onset pulmonary ede... Chemical Terrorism Response During a Chemical Attack Chemical Agents Nerve Agents Foundations . The nerve agents are classified as either “G” agents or “V” agents and most recently include the Russian-based novice or “Nov... . The nerve agents function by affecting acetylcholine (ACh). Acetylcholine receptors are found on the postsynaptic membranes of... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Vesicants Foundations . At temperatures below 14°C, mustard exists in the solid form. Once in the liquid or gaseous form, mustard gas can be recognize... . Mustard gas can enter the body after inhalational, dermal, or oral exposures. After entering the body, it functions as an alky... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Cyanide Foundations . Cyanide salts and hydrocyanic acid are commonly used for metal cleaning, precious metal extraction, photographic processes, el... . Cyanide is a cellular toxin. It binds to both Fe3+ and cobalt. By binding and inactivating the enzyme cytochrome oxidase, whic... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 56 - Oral Medicine Introduction Disorders of the Tooth Foundations Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Disorders of the Gingiva and Periodontium Foundations Anatomy, Physiology, and Pathophysiology . Periodontitis is inflammation of the supporting structures of the teeth (gingiva, alveolar bone, cementum, and periodontal lig... . The gingiva and surrounding tissue can also become inflamed leading to a condition known as pericoronitis. As teeth start to e... . Gingival hyperplasia is an overgrowth of the gum tissue surrounding the teeth. It can occur secondary to poor oral hygiene, de... Clinical Features Differential Diagnoses Diagnostic Testing Gingivitis and Periodontitis Pericoronitis Management Gingivitis and Periodontitis Pericoronitis Disposition Gingivitis and Periodontitis Pericoronitis Disorders Involing Dental Procedures Foundations Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Odontogenic and Deep Neck Infections Foundations Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Dentoalveolar Trauma Foundations Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Dental Fractures Tooth Avulsion Luxation and Alveolar Fractures Soft Tissue Injuries Disposition Foundations Anatomy, Physiology, and Pathophysiology . The cause of TMD is debated, but jaw clenching and grinding associated with stress is thought to contribute. Tooth malocclusio... . TMJ dislocation occurs when the condyle travels anteriorly along the eminence and becomes locked in the anterosuperior aspect ... Clinical Features Temporomandibular Joint Disorder Temporomandibular Joint Dislocation Differential Diagnoses Diagnostic Testing Management Temporomandibular Joint Disorder Temporomandibular Joint Dislocation Disposition References 57 - Ophthalmology Overview Traumatic Conditions Foundations Periorbital Contusions and Eyelid Lacerations Clinical Features and Differential Diagnoses Diagnostic Testing Management and Disposition Conjunctival and Scleral Injuries: Subconjunctival Hemorrhage, Conjunctival Laceration, and Scleral Laceration Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Corneal Injuries: Corneal Abrasions, Foreign Bodies, and Lacerations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition . There is no evidence that the treatment of corneal abrasions with topical antibiotics, as often recommended, has any beneficia... . Foreign bodies of the cornea and conjunctiva, especially those containing iron (given the risk of rust deposition over time), ... . Large but partial corneal lacerations should be evaluated by ophthalmology for potential closure in the operating room versus ... Anterior Segment Injuries: Traumatic Hyphema, Iritis, Cyclodialysis, and Lens Dislocation Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition . With isolated traumatic iritis, the primary goals of treatment are minimizing scarring, decreasing inflammation, and pain reli... . Lens subluxations or dislocations can be vision-threatening emergencies and should be evaluated by an ophthalmologist in the ... Posterior Segment/Ocular Injuries: Commotio Retinae, Retinal Detachment, Intraocular Foreign Body, and Perforated Globe Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition . A traumatic retinal detachment, if detected and treated early before the macula is involved, carries a good prognosis. Approxi... . For patients with a possible globe perforation (open globe) with or without an intraocular foreign body, examine the eye with ... Retrobulbar and Peribulbar Injuries: Orbital Wall Fracture, Retrobulbar Hemorrhage, and Optic Nerve Injury Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition . Prophylactic antibiotics are commonly administered for orbital wall fractures that extend into an adjacent sinus, although the... . The loss of vision associated with a retrobulbar hematoma is thought to be irreversible within 60 to 100 minutes after the ons... . Once the determination of the type and degree of optic neuropathy is determined, treatment options can be considered. There is... Chemical Exposures and Glues Clinical Features and Differential Diagnoses Diagnostic Testing Management and Disposition Inflammatory Conditions Foundations The Conjunctiva and Cornea: Keratitis, Pterygium, and Pinguecula Clinical Features Differential Diagnoses Diagnostic Testing Management . Superficial punctate keratitis and UV keratitis are treated the same as corneal abrasions because all entail injury to the cor... . Treatment of pterygium and pinguecula are similar, and it includes UV protection, lubrication, and treatment of acute inflamma... Disposition The Globe: Uveitis, Scleritis, and Episcleritis Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition The Orbit: Orbital Pseudotumor, Orbital Apex Syndrome, and Thyroid Orbitopathy Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Infectious Conditions Foundations The Conjunctiva: Allergic, Viral and Bacterial Conjunctivitis, and Ophthalmia Neonatorum Clinical Features and Differential Diagnoses Diagnostic Testing Management and Disposition . Allergic conjunctivitis and viral conjunctivitis are usually self-limited and can be treated with supportive measures such as... . Although bacterial conjunctivitis is typically self-limited, most resolving in 1 to 2 weeks without treatment, topical antibi... . Hospitalization of neonates with blood and cerebrospinal fluid (CSF) examination may be indicated for ophthalmia neonatorum. N... The Cornea: Corneal Ulcers, Herpes Simplex Keratitis, and Herpes Zoster Keratitis Clinical Features Differential Diagnoses Diagnostic Testing Management . Topical anti-microbial therapy for corneal ulcers and infiltrates is appropriate initial therapy, although systemic antibioti... . Herpes simplex keratitis is the most common cause for corneal transplants in the United States. Emergent ophthalmologic consul... . Herpes zoster ophthalmicus accounts for approximately 10% to 20% of all zoster cases and necessitates emergent ophthalmologic ... Disposition The Eyelids and Periorbital Area: Hordeolum, Chalazion, Dacryocystitis, Blepharitis, and Cellulitis Clinical Features Differential Diagnoses Diagnostic Testing Management . Hordeola and chalazia are typically self-limited and can resolve on their own when the glands become unobstructed. Conservati... . The most common causative organisms in dacryocystitis are S. aureus, S. pneumoniae, H. influenzae, Serratia marcescens, and Ps... . The initial treatment of blepharitis is conservative, designed to remove residual oils and scurf, and entails warm massage wit... . If pre-septal cellulitis in a patient with no other underlying medical conditions is diagnosed with certainty, the patient ca... Disposition The Globe: Endophthalmitis Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Acute Angle-Closure Glaucoma Foundations Clinical Features Differential Diagnoses Diagnostic Testing Primary Disorders of Vision Foundations Blurred Vision: Optic Neuritis, Toxic and Metabolic Disturbances, and Papilledema Clinical Features Differential Diagnoses Diagnostic Testing . With optic neuritis, visual acuity will usually be abnormal, and the patient may have variable visual field defects with centr... . These processes are bilateral, progressive, and symmetrical and may manifest with a significant drop in visual acuity along wi... . Early or mild papilledema may be difficult to detect with the direct ophthalmoscope. When clinical suspicion is high, consulta... Management Disposition Floaters, Flashes, and Field Deficits: Vitreous and Retinal Disorders Clinical Features Differential Diagnoses Diagnostic Testing . With a vitreous hemorrhage, direct ophthalmoscopy reveals a reddish haze in mild cases and a black reflex in severe cases. Det... . With a retinal detachment, visual acuity can range from minimally changed to severely decreased. Visual field deficits relate ... . A chiasmic or cortical cause of a visual field disturbance can usually be made by confrontation visual field testing. The clas... Management Disposition Sudden Monocular Vision Loss: Retinal Artery and Vein Occlusion, and Ischemic Optic Neuropathy Clinical Features Differential Diagnoses Diagnostic Testing Management . Like acute ischemic stroke, CRAO is a time-sensitive process. Animal models suggest that the retina will likely make a full r... . An ultimate visual acuity better than 20/200 is seen in over 80% of patients with a non-ischemic CRVO but in less than 10% of... . Temporal arteritis with evolving vision loss or amaurosis fugax from A-AION represents a distinct clinical emergency. Untreat... Disposition Functional Vision Loss Diplopia Anisocoria Foundations Clinical Features Adie’s and Argyll Robertson Pupils Pharmacologic Mydriasis and Miosis Third-Nerve Palsy Horner Syndrome Physiologic and Headache-Associated Anisocoria Diagnostic Testing, Management, and Disposition Nystagmus Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management References 58 - Otolaryngology Otitis Media Foundations Background and Importance Anatomy and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Otitis Externa Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Necrotizing (Malignant) External Otitis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Mastoiditis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Sudden Hearing Loss Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Epistaxis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Sialolithiasis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Neck Masses Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Disclaimer References 59 - Asthma Foundations Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Signs and Symptoms Risk Factors Specific Contexts Cough Variant Cigarette Smokers Athletes Perimenstrual Asthma Elderly Obesity Aspirin-Exacerbated Respiratory Disease Differential Diagnoses Diagnostic Testing Peak Expiratory Flow Pulse Oximetry Capnography Blood Gas Other Blood Testing Radiology Point of Care Ultrasound Electrocardiogram Management Oxygen Administration Adrenergic Medications Inhaled Beta2 Agonists Long-Acting Beta-2 Agonists Intravenous Beta2 Agonists Subcutaneous Beta2 Agents Epinephrine Corticosteroids Systemic Corticosteroids Inhaled Corticosteroids Corticosteroids and Discharged Patients Anticholinergic Medications Magnesium Methylxanthines Leukotriene Modifiers Antibiotics Sedatives Ketamine Heliox High-Flow Nasal Canula Noninvasive Ventilation Mechanical Ventilation Extracorporeal Membrane Oxygenation Other and Future Therapies Special Situations Pregnancy Near Fatal Asthma Clinical Approach to Acute Severe Asthma Disposition References 60 - Chronic Obstructive Pulmonary Disease Foundations Background Anatomy/Physiology/Pathophysiology Clinical Features Acute Exacerbations Respiratory Failure Differential Diagnosis for the Emergency Presentation Diagnostic Testing Chest Radiography Pulse Oximetry Blood Gas Analysis Electrocardiogram Laboratory Tests Management Short-Acting Beta Agonists Glucocorticoids Antibiotics Adjunctive Treatments Respiratory Support Oxygenation Non-Invasive Ventilation High-Flow Nasal Cannula Invasive Ventilation Disposition References 61 - Upper Respiratory Tract Infections Pharyngitis Foundations Clinical Features Differential Diagnosis for Emergency Presentation Diagnostic Testing Management Disposition Laryngitis Foundations Clinical Features Differential Diagnosis for Emergency Presentation Diagnostic Testing Management Disposition Epiglottitis Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnosis for Emergency Presentation Diagnostic Testing Management Disposition Ludwig Angina Foundations Clinical Features Differential Diagnosis for Emergency Presentation Diagnostic Testing Management Disposition Retropharyngeal Abscess Foundations Clinical Features Differential Diagnosis for Emergency Presentation Diagnostic Testing Management Disposition Parapharyngeal Abscess Foundations Clinical Features Differential Diagnosis for Emergency Presentation Diagnostic Testing Management Disposition Rhinosinusitis Foundations Clinical Features Differential Diagnosis for Emergency Presentation Diagnostic Testing Management Disposition References 62 - Pneumonia Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 63 - Pleural Disease Spontaneous Pneumothorax Foundations Background and Importance Anatomy and Physiology Clinical Features Differential Diagnosis Diagnostic Testing Point of Care Ultrasound Management Primary Spontaneous Pneumothorax Secondary Spontaneous Pneumothorax Tension Pneumothorax Disposition Pleural Effusion Foundations Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition References 64 - Acute Coronary Syndromes Epidemiology Stable Angina Unstable Angina Acute Myocardial Infarction Pathophysiology Clinical Features Prehospital Evaluation Emergency Department Evaluation History . A description of typical symptoms may not be present in ACS. This nontraditional presentation may be a result of atypical feat... Physical Examination of the ACS Patient Early Complications of Acute Myocardial Infarction Differential Diagnoses Diagnostic Testing Electrocardiography Electrocardiographic Abnormalities in Acute Coronary Syndromes Anatomic Location of Acute Myocardial Infarction Electrocardiographic Differential Diagnosis of ST Segment Elevation Non–ST Segment Elevation Myocardial Infarction Electrocardiographic Adjuncts in the Diagnosis of Acute Coronary Syndrome Limitations of Electrocardiography in Acute Coronary Syndrome Chest Radiography Serum Markers Troponin Testing Other Serum Markers Exercise Stress Testing Echocardiography Myocardial Scintigraphy (Nuclear Imaging) Coronary Computed Tomography Angiography Risk Stratification Instruments Management Pharmacologic Intervention Oxygen Nitroglycerin Morphine and Other Opioid Analgesic Agents Beta-Adrenergic Blockers Angiotensin-Converting Enzyme Inhibitors HMG–Coenzyme A Reductase Inhibitors Calcium Channel Blockers Antiplatelet Therapy . Aspirin, the prototypical antiplatelet agent, is the most cost-effective treatment in ACS care. It irreversibly acetylates pl... . The P2Y12 inhibitors include the thienopyridines ticlopidine, clopidogrel, and prasugrel, as well as ticagrelor and cangrelor.... . Glycoprotein IIb/IIIa receptor inhibitors (GPIs) are potent antiplatelet agents; they include abciximab, eptifibatide, and tir... Antithrombins . The term heparin refers not to a single structure but to a family of mucopolysaccharide chains of varying lengths and composit... . The direct thrombin inhibitor bivalirudin is a potent antithrombin anticoagulant providing significant theoretical advantages ... Reperfusion Therapies Fibrinolytic Therapy . Options for fibrinolytic therapy include streptokinase (the original fibrinolytic agent) and three types of plasminogen activa... . In the absence of contraindications, fibrinolytic therapy should be considered in patients with STEMI and the onset of ischemi... . Combined with the patient’s history and physical examination, the 12-lead ECG is the key determinant of eligibility for fibri... . Past trials do not provide evidence to support withholding fibrinolytic therapy or choosing one particular agent over another ... . The generally accepted therapeutic time window for administration of a fibrinolytic agent after the onset of STEMI is 12 hours... . Patients with a history of chronic hypertension should not be excluded from fibrinolytic therapy if their blood pressure is ad... . Active diabetic hemorrhagic retinopathy is a strong relative contraindication to fibrinolytic therapy because of the potential... . CPR is not a contraindication to fibrinolytic therapy unless CPR is prolonged—more than about 10 minutes—or extensive chest tr... . A history of a previous stroke or TIA is a major risk factor for hemorrhagic stroke after treatment with fibrinolytic therapy.... . In the setting of STEMI, a previous MI should not preclude consideration for treatment with fibrinolytic agents. Without treat... . Recent surgery or trauma is considered a relative contraindication to fibrinolytic therapy. The term recent has been subject t... . There is minimal clinical experience with fibrinolysis in premenopausal women. Any excessive vaginal bleeding that may occur a... . Although fibrinolysis has widespread availability and a proven ability to improve coronary flow, limit infarct size, and impro... . Historically, rescue PCI was considered advantageous in patients whose infarct-related arteries failed to reperfuse after fib... . Facilitated percutaneous coronary intervention refers to combination therapy involving fibrinolysis coupled with emergent PCI.... . As noted, the two primary choices for reperfusion therapy in the STEMI patient include fibrinolysis and PCI. Important issues ... . Patients with STEMI complicated by cardiogenic shock, occurring in up to 10% of cases, demand special consideration because of... Resuscitated Cardiac Arrest with Suspected ACS Disposition Transfer of a Patient with Acute Coronary Syndrome Missed Diagnosis of Acute Coronary Syndrome References 65 - Dysrhythmias Foundations Cardiac Cellular Electrophysiology Anatomy and Conduction Mechanisms of Dysrhythmia Formation Classification of Antidysrhythmic Drugs Class IA Agents Procainamide Class IB Agents Lidocaine Class IC Agents Flecainide Propafenone Class II Agents Esmolol Metoprolol Class III Agents Amiodarone Ibutilide Sotalol Dofetilide Dronedarone Class IV Agents Diltiazem Verapamil Miscellaneous Agents Adenosine Digoxin Magnesium Isoproterenol Clinical Features Initial Assessment of Stable Patients Differential Diagnosis Management Sinus Bradycardia and Sinoatrial and Atrioventricular Block Sinus Bradycardia Sinus Dysrhythmia Sinus Arrest and Sinoatrial Exit Block Sick Sinus Syndrome Atrioventricular Block First-Degree Atrioventricular Block Second-Degree Atrioventricular Block . Type I second-degree AV block, also called Wenckebach or Mobitz I AV block, is associated with progressive impairment of cond... . Type II second-degree AV block, or Mobitz II block, is a conduction block just below the level of the AV node. On the surface... Third-Degree Atrioventricular Block Extrasystoles Premature Atrial Contractions Premature Ventricular Contractions Narrow-Complex Tachycardia Sinus Tachycardia Atrial Tachycardia Atrial Fibrillation Atrial Flutter Atrioventricular Nodal Reentrant Tachycardia Junctional Tachycardia Preexcitation and Accessory Pathway Syndromes Wide-Complex Tachycardia Ventricular Tachycardia Torsades de Pointes Brugada Syndrome Disposition References 66 - Implantable Cardiac Devices Clinical Features Pacemaker Terminology Pacemaker Components History Physical Examination 12-Lead Electrocardiogram Differential Diagnosis Complications of Implantation Infection Venous Thrombosis and Stenosis Complications of Existing Pacemakers The “Pacemaker Syndrome” Complications Unique to Biventricular Pacing Pacemaker Malfunction Failure to Capture Inappropriate Sensing Inappropriate Pacemaker Rate Diagnostic Testing Chest Radiograph 12-Lead Electrocardiogram Pacemaker Interrogation Magnetic Resonance Imaging in Patients with a Pacemaker Management Resuscitation Disposition Clinical Features Terminology and Components Differential Diagnosis Complications of Implantation Malfunction Diagnostic Testing Management ICD Defibrillation Resuscitation Disposition Mechanical Circulatory Support Devices Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition References 67 - Heart Failure Foundations Background and Importance Epidemiology Congestion and Preload Afterload Disorganized Contraction Myocardial Infarction Versus Injury Cardiorenal Syndrome Other Factors Clinical Features History and Physical Exam Precipitants Differential Diagnosis Diagnostic Testing Electrocardiogram Chest Radiography Laboratory Testing Lung Ultrasound Echocardiography Management Initial Evaluation Blood Pressure Considerations Vascular Phenotype Cardiac Phenotype Disposition References 68 - Pericardial and Myocardial Disease Dilated Cardiomyopathy Foundations Clinical Features Diagnostic Testing Differential Diagnosis Management and Disposition Disposition Hypertrophic Cardiomyopathy Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Restrictive Cardiomyopathy Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Peripartum Cardiomyopathy Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Takotsubo Syndrome Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Arrhythmogenic Right Ventricular Cardiomyopathy Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Channelopathies Myocarditis Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Chagas Disease Cocaine Cardiotoxicity Sudden Death Pericardial Disease Pericarditis Foundations Clinical Findings Differential Diagnosis Diagnostic Testing Management Disposition Uremic Pericardial Disease Post–Myocardial Infarction Pericarditis Postinjury Pericarditis Neoplastic Pericardial Disease Radiation-Induced Pericarditis Miscellaneous Causes of Pericarditis Pericardial Effusion Purulent Pericarditis Constrictive Pericarditis Cardiac Tamponade Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Pneumopericardium References 69 - Infective Endocarditis and Valvular Heart Disease Infective Endocarditis Foundations Background and Importance Pathophysiology and Microbiology Clinical Features and Differential Diagnosis Diagnostic Testing Management Disposition Prophylaxis Rheumatic Fever Foundations Background and Importance Pathophysiology Clinical Features and Differential Diagnosis Diagnostic Testing Management and Disposition Valvular Heart Disease Foundations Anatomy and Physiology Mitral Stenosis Pathophysiology Clinical Features Management Mitral Regurgitation Pathophysiology Clinical Features Acute Mitral Regurgitation Chronic Mitral Regurgitation Management Mitral Valve Prolapse Pathophysiology Clinical Features Management Aortic Stenosis Pathophysiology Clinical Features Management Aortic Regurgitation Pathophysiology Clinical Features Acute Aortic Regurgitation Chronic Aortic Regurgitation Management Complications of Prosthetic Valves Structural Failure Valve Thrombosis Systemic Embolization Hemolysis Endocarditis Disposition References 70 - Hypertension Background and Importance Importance Definition of Hypertension and Relevant Terminology Physiology of Hypertension Neurohormonal Dysregulation Vascular Modulation Sodium Intake Psychosocial Stress Obesity Pathophysiology of Target-Organ Damage Clinical Features Hypertensive Emergency Hypertensive Encephalopathy Other Hypertension-Related Emergencies Acute Target Organ Damage in the Context of Systemic Illness Absence of Target Organ Dysfunction Differential Diagnoses Diagnostic Testing Management Acute Blood Pressure Control Antihypertensive Therapy Blood Pressure Goals Acute Coronary Syndrome and Acute Heart Failure Aortic Dissection Acute Ischemic Stroke Spontaneous Intracranial Hemorrhage Hypertensive Encephalopathy Acute Kidney Injury Preeclampsia and Eclampsia Sympathetic Crises Chronic Antihypertensive Therapy Disposition References 71 - Aortic Dissection Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition References 72 - Abdominal Aortic Aneurysm Epidemiology Pathophysiology Natural History Clinical Features Unruptured Aneurysms Ruptured Aneurysms Pain-Hypotension-Mass Triad Aortoenteric Fistula Arteriovenous (Aortocaval) Fistula Differential Diagnoses Diagnostic Testing Abdominal Radiography Ultrasonography Computed Tomography Other Diagnostic Modalities Management Ruptured Aneurysms Fluid Resuscitation Diagnostic Confirmation Surgery and Mortality Intact Asymptomatic Aneurysms Traditional Repair Endovascular Repair Survival Late Complications of Repair Graft Infection Aortoenteric Fistula Pseudoaneurysm (Anastomotic Aneurysm) Complications of Endovascular Aneurysm Repair Disposition References 73 - Peripheral Arteriovascular Disease Foundations Background Arterial Anatomy Pathophysiology Atherosclerosis Arterial Embolism .. Most arterial emboli (85%) originate from thrombus formation in the heart. Left ventricular thrombus formation resulting from... .. Atheroembolism refers to microemboli consisting of cholesterol, calcium, and platelet aggregates dislodged from proximal comp... Arterial Thrombosis Aneurysms Inflammation Trauma Vasospasm Arteriovenous Fistulae Clinical Features History Physical Examination Inflammation Vasospasm Differential Diagnosis Diagnostic Testing Noninvasive Assessment Contrast Arteriography Management Noninvasive Therapy Acute Anticoagulation with Heparin Fibrinolytic Therapy Invasive Therapy Fogarty Catheter Thrombectomy Peripheral Percutaneous Transluminal Angioplasty Grafting Hyperbaric Therapy Disposition Specific Arteriovascular Diseases Diseases of Chronic Arterial Insufficiency Arteriosclerosis Obliterans Clinical Features .. Acute arterial occlusion from embolism, thrombosis, or trauma is ruled out primarily by history. Chronic arterial insufficien... .. Atheromatous emboli from proximal ulcerated plaques or aneurysms cause small scattered ischemic lesions in the toes, feet, or... .. Exercise-induced claudication should be distinguished from nocturnal muscle cramps frequently seen in older patients. Aortoi... .. The first step is to identify patients whose symptoms are the sole result of arteriosclerosis obliterans without coexistent t... Buerger Disease (Thromboangiitis Obliterans) . First described by Buerger in 1908, thromboangiitis obliterans is an idiopathic inflammatory occlusive disease primarily invol... . Clinical criteria for Buerger disease include (1) a history of smoking, (2) onset before the age of 50, (3) infrapopliteal art... . Arteriosclerosis obliterans is most likely in patients older than 50 years old who have signs of peripheral ischemia. In young... . Adherence to diagnostic clinical criteria should suffice for ED diagnosis of Buerger disease. Noninvasive vascular laboratory ... . Permanent complete abstinence from tobacco is the only effective treatment for Buerger disease. If a patient does not complete... Diseases of Acute Arterial Occlusion Arterial Embolism Clinical Features . Patients with acute arterial occlusion usually exhibit some variant of the five Ps: pain, pallor, pulselessness, paresthesias,... . The physical examination can help differentiate arterial embolism from in situ thrombosis. Sudden loss of a pulse is the hallm... . Phlegmasia cerulea dolens is a massive iliofemoral deep venous thrombosis. The initial symptom is the acute onset of a swollen... . Acute arterial embolism is a surgical emergency. The likelihood of limb salvage decreases after 4 to 6 hours. On the basis of ... Atheroembolism (Blue Toe Syndrome) . The typical presentation of atheroembolism is the sudden onset of a small, cyanotic, and tender area on the foot, typically th... . A variety of conditions can mimic blue toe syndrome. Acrocyanosis is painless, has a symmetrical distribution, and is located ... . Treatment is directed toward identifying and removing the proximal source of atheroembolism. CT angiography is the diagnostic ... Arterial Thrombosis Physical Exam . Heparinization (80 units/kg bolus, followed by a maintenance infusion of 18 units/kg/hr) should be started when the diagnosis ... Peripheral Arterial Aneurysms Lower Extremity Upper Extremity Viscera . Splenic artery aneurysms account for 60% of all visceral arterial aneurysms. They are the only aneurysms that are more common ... . Hepatic artery aneurysms represent 20% of visceral artery aneurysms. The lesions are caused by atherosclerosis, infection (mos... . Superior mesenteric artery aneurysms are the third most common visceral aneurysms. Nearly 60% are infected aneurysms caused by... Traumatic Aneurysms Infected Aneurysms . The term mycotic aneurysm is a source of confusion because there is no association with fungal disease. Although used to descr... . Currently, the most common cause of an infected aneurysm is sepsis with hematogenous spread of bacteria, such as Salmonella, S... . The incidence of infection in patients with preexisting atherosclerotic aneurysms is estimated at 3% to 4%, and patients with ... . Post-traumatic infected pseudoaneurysms result from invasive hemodynamic monitoring, angiography, and intravenous drug use. T... Vasospastic Disorders Thoracic Outlet Syndrome Clinical Features . The most reliable test in screening for thoracic outlet syndrome is the elevated arm stress test (EAST).44 With the patient si... . Cervical spine radiographs with oblique views and chest radiographs identify skeletal abnormalities (first rib, cervical rib, ... Differential Diagnosis Management . The correct diagnosis of thoracic outlet syndrome can be achieved in more than 90% of patients with a careful history, physica... Peripheral Arteriovenous Fistulae Physical Exam Differential Diagnosis Management Vascular Abnormality Caused by Drug Abuse Principles Clinical Features Management References 74 - Pulmonary Embolism and Deep Vein Thrombosis Foundations Background and Importance Anatomy, Pathology, and Pathophysiology of VTE Deep Vein Thrombosis Clinical Features Differential Diagnosis Diagnostic Testing Pretest Probability Estimation Laboratory Evaluation Radiographic Evaluation Management Assessing Bleeding Risk Superficial Vein Thrombophlebitis Isolated Calf Vein Thrombosis Phlegmasia Cerulean and Alba Dolens Upper Extremity Venous Thromboses Complications Disposition Pulmonary Embolism Clinical Features Symptoms Vital Signs Physical Examination Differential Diagnosis Diagnostic Testing Bedside Assessment Pretest Probability Assessment Pulmonary Embolism Rule-Out Criteria D-Dimer Testing Computed Tomography Pulmonary Angiography Ventilation/Perfusion Scan Pregnant Women Clinical Course Management Airway, Oxygenation, and Ventilation Hemodynamic Resuscitation Pulmonary Vasodilators Standard Anticoagulation . All anticoagulants commonly used in the ED, including the DOACs, now have effective reversal agents. The anticoagulant effect ... Thrombolytic (Fibrinolytic) Therapy Catheter-Directed Interventions Surgical Embolectomy Inferior Vena Cava Filters Pulmonary Embolism Response Teams (PERT) Mortality and Morbidity Disposition References 75 - Esophagus, Stomach, and Duodenum Dysphagia Foundations Anatomy and Pathophysiology Oropharyngeal Dysphagia . Neuromuscular disease causes approximately 80% of cases of oropharyngeal dysphagia, with most remaining causes being localized... . Congenital anomalies of the aortic arch may cause dysphagia in children and adults. In children, respiratory symptoms are usua... Esophageal Dysphagia . Esophageal dysphagia is caused by mechanical lesions or a motility disorder. Mechanical lesions may be intrinsic or extrinsic ... . Patients with esophageal dysphagia who have no readily identifiable mechanical cause may have a motor disorder. Intrinsic moto... Clinical Features Esophageal Dysphagia Differential Diagnoses Diagnostic Testing Management Disposition Foreign Bodies Foundations Background Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Overview Upper Esophagus Lower Esophagus Stomach Disposition Esophageal Perforation Foundations Background Anatomy and Physiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Esophagitis Foundations Gastroesophageal Reflux Disease Eosinophilic Esophagitis Infectious Esophagitis Pill Esophagitis Radiation-Induced Esophagitis Clinical Features Gastroesophageal Reflux Disease Eosinophilic Esophagitis Infectious Esophagitis Pill Esophagitis Differential Diagnoses Diagnostic Testing Management Gastric Reflux Eosinophilic Esophagitis Infectious Esophagitis Pill Esophagitis Disposition Gastritis and Peptic Ulcer Disease Foundations Background Pathophysiology Clinical Features Complications Differential Diagnoses Diagnostic Testing Management Antacids Histamine Blockers Proton Pump Inhibitors Prostaglandins Other Agents Disposition Gastric Volvulus Foundations Clinical Features Complications Differential Diagnoses Diagnostic Testing Management Disposition References 76 - Liver and Biliary Tract Disorders Hepatic Disorders Hepatitis Viral Hepatitis Foundations . Hepatitis A virus (HAV), is an RNA enteroviral picornavirus. It is spread by the fecal-oral route directly or through fecally... . Hepatitis B virus (HBV) is a virion that envelopes DNA polymerase, hepatitis B surface antigen (HBsAg), and hepatitis B core a... Hepatitis C and E . Hepatitis delta virus (HDV) is a defective RNA virus that can infect only patients who are actively producing HBsAg (HBV disea... . Hepatitis E, which is associated with fecal-oral transmission, is encountered most often in Asia, Africa, or Russia. Hepatiti... Clinical Features Differential Diagnosis Diagnostic Testing Management . Effective preexposure and postexposure prophylaxis for HAV and HBV are available. For HBV exposure in an unimmunized patient, ... Disposition Alcoholic Hepatitis Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Autoimmune Hepatitis Foundations Diagnosis Management Disposition Cirrhosis Foundations Clinical Features Diagnostic Testing Management Ascites Gastrointestinal Bleeding Hepatorenal Syndrome Hepatic Encephalopathy Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Spontaneous Bacterial Peritonitis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Hepatic Abscesses Pyogenic Abscess Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Amebic Abscess Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Liver Disease of Pregnancy Benign Cholestasis Acute Fatty Liver Budd-Chiari Syndrome Liver Transplantation Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Special Considerations Disposition Cholecystitis Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Special Considerations . Acute cholecystitis absent of stones is more common in older adults and is often found in patients who are recovering from non... . This is an uncommon variant of cholecystitis, occurring in approximately 1% of cases. It is characterized by the presence of g... Disposition Cholangitis Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Sclerosing Cholangitis Aids Cholangiopathy References 77 - Pancreas Pancreatitis Anatomy, Physiology, and Pathophysiology Acute Pancreatitis Foundations Clinical Features Differential Diagnoses Diagnostic Testing . Laboratory diagnosis of pancreatitis is made primarily by serum lipase and amylase levels. Lipase is an enzyme produced predom... . Abdominal imaging by computed tomography (CT) or magnetic resonance imaging (MRI) is not routinely recommended in the diagnosi... . Predicting the disease course in acute pancreatitis is challenging but important given the range in severity from mild cases t... Management Disposition Chronic Pancreatitis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Pancreatic Cancer Foundations Clinical Features References 78 - Small Intestine Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Pathophysiology Clinical Features History Physical Examination Differential Diagnosis Diagnostic Testing Laboratory Imaging Management Disposition Acute Mesenteric Ischemia Foundations Background and Importance Anatomy and Physiology Pathophysiology Mesenteric Arterial Embolism Mesenteric Arterial Thrombosis Nonocclusive Mesenteric Ischemia Mesenteric Venous Thrombosis Unusual Causes of Mesenteric Ischemia Clinical Features . The history at presentation of mesenteric ischemia is largely dependent on the nature of the underlying cause. The traditional... . The pain in acute mesenteric ischemia is typically described as being out of proportion to the physical examination findings. ... Differential Diagnosis Diagnostic Testing Laboratory Tests Imaging Management Complications Disposition References 79 - Acute Appendicitis Principles Background Anatomy and Physiology Pathophysiology Clinical Features History Physical Examination Differential Diagnosis Diagnostic Testing General Principles Laboratory Testing White Blood Cell Count C-Reactive Protein Urinalysis Other Laboratory Tests Combined Laboratory Tests Clinical Decision Instruments Imaging General Principles Plain Radiographs Graded Compression Ultrasound Computed Tomography Magnetic Resonance Imaging Summary of Imaging Methods . Graded compression US may be considered first. In nonpregnant females, a pelvic US may also be considered to assess for pelvic... . US should be the initial study of choice, followed by MRI of the abdomen without gadolinium in cases of nondiagnostic or negat... Management Supportive Care Antibiotic Therapy Definitive Treatment Uncomplicated Appendicitis Complicated Appendicitis Disposition References 80 - Gastroenteritis Foundations Background and Importance Clinical Features Patient History Physical Examination Differential Diagnoses Diagnostic Testing Management Disposition Bacterial Gastroenteritis Invasive Bacteria Campylobacter Enteritis Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Salmonellosis Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Shigellosis Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Yersinia enterocolitica Gastroenteritis Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Vibrio parahaemolyticus Gastroenteritis Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Shiga Toxin–Producing Escherichia coli Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Noninvasive Toxin-Forming Bacteria Staphylococcus spp Epidemiology Pathophysiology Clinical Features Management Clostridium perfringens Epidemiology Pathophysiology Clinical Features Management Bacillus cereus Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Cholera and Noncholera Vibrio Species Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Enterotoxigenic Escherichia coli Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Clostridium difficile Colitis Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Viral Gastroenteritis Norovirus Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Rotavirus Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Parasites Giardia Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Amebiasis Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Food Poisoning Foundations Clinical Features Diagnostic Testing Management Scombroid Fish Poisoning Epidemiology Pathophysiology Clinical Features Management Ciguatera Fish Poisoning Epidemiology Pathophysiology Clinical Features Management Specific Groups With Gastroenteritis Traveler’s Diarrhea Epidemiology Pathophysiology Clinical Features Diagnostic Testing Management Epidemiology and Pathophysiology Clinical Features Diagnostic Testing Management References 81 - Large Intestine Irritable Bowel Syndrome Foundations Background Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Diverticular Disease Foundations Background Anatomy, Physiology, and Pathophysiology Clinical Features Diverticulosis Diverticulitis Differential Diagnoses Diagnostic Testing Management Diverticulosis Uncomplicated Diverticulitis Complicated Diverticulitis Disposition Large Bowel Obstruction Foundations Background Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Laboratory Tests Imaging Studies . Both supine and upright plain films are advised for the workup of LBO and ACPO (Fig. 81.4). A distended colon (>6 cm diameter)... . CT is a valuable tool for determining the cause of the obstruction, especially if it is a diverticular abscess or intussuscept... . Water-soluble contrast enemas are no longer advised, given that CTs are now more accurate in making the diagnosis of LBO. Col... Management Disposition Volvulus Foundations Background Anatomy, Physiology, and Pathophysiology . Residents of long-term care facilities and patients with neurologic or psychiatric disease are predisposed to sigmoid volvulu... . The mobility of the colonic segment involving the cecum is likely a result of a congenital incomplete fusion of the cecal mese... Clinical Features Sigmoid Volvulus Cecal Volvulus Differential Diagnoses Diagnostic Testing Sigmoid Volvulus Cecal Volvulus Management Sigmoid Volvulus Cecal Volvulus Disposition Intussusception Foundation Background Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Ultrasound Examination Plain Radiography Computed Tomography Colonoscopy Management Disposition Inflammatory Bowel Disease Foundations Background Anatomy, Physiology, and Pathophysiology Crohn Disease Ulcerative Colitis Clinical Features Toxic Megacolon Extraintestinal Manifestations Differential Diagnoses Diagnosis Management Crohn Disease . Since CD can affect any area of the GI tract, location of disease and severity of symptoms are important factors in treatment ... . For moderate to severe CD that is responsive to systemic steroids, early introduction to an immunomodulator, such as thiopurin... . Severe to fulminant disease requires aggressive therapy, gastroenterology consultation, and often hospitalization. For patient... Ulcerative Colitis . For mild to moderate UC, aminosalicylates (5-ASA) including mesalazine and sulfasalazine are mainstays of treatment.18 Combin... . Vedolizumab was approved to treat moderate to severe UC resistant to immunomodulators, steroids, or anti-TNF therapy. While s... Managing Special Populations With Irritable Bowel Syndrome Toxic Megacolon Disposition Colonic Ischemia Foundations Background Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Laboratory Tests Imaging Studies . Plain radiographs often show only nonspecific dilated bowel. Findings specific for CI occur in approximately 20% of patients. ... . Although CT does not allow the definitive diagnosis of CI, it is useful to support the clinical suspicion, assess the extent o... . Emergent colonoscopy should be performed after the colon is prepped with an enema. It is the most useful within 48 hours of sy... . Angiography is usually not helpful in the diagnosis or management of CI. In most cases, the blood flow defect is at the microv... Management Disposition Stercoral Colitis Foundations Background Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnosis Management Disposition Radiation Proctocolitis Foundations Background Anatomy, Physiology, and Pathophysiology . Intestinal epithelium normally sloughs off and is replaced at a rapid rate. After the initiation of radiation therapy, growth ... . The pathologic mechanism in chronic RP is entirely different and results from a progressive endarteritis, with abnormal tissue... Clinical Features Differential Diagnosis Diagnostic Testing Management Acute Radiation Proctocolitis Chronic Radiation Proctocolitis Disposition Neutropenic Enterocolitis Foundations Background Anatomy, Pathology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Laboratory Tests Radiologic Tests Management Disposition References 82 - Anorectum Clinical Features Specific Anorectal Problems Hemorrhoids Foundations Clinical Features Management Anal Fissures Foundations Clinical Features Management Abscesses and Fistulae Foundations Management . Perirectal and perianal abscesses account for about half of anorectal abscesses. They produce painful swelling at the anal ver... . Ischiorectal abscesses account for one-fifth to one-quarter of anorectal abscesses. They form outside the sphincter muscles ... . One-fourth of abscesses form in the intersphincteric space, located deep to the external sphincter and inferior to the levato... . Supralevator abscesses, which cause less than 5% of anorectal abscesses, present as perianal and buttock pain associated with ... . Postanal abscesses are uncommon and occur posterior to the rectum, deep to the external sphincter and inferior to the levator ... . A large, communicating, horseshoe-shaped abscess may form in the ischiorectal, intersphincteric, or supralevator spaces. The ... . A delay in the management of an anorectal abscess may lead to the destruction of surrounding tissue, especially in diabetic or... . A fistula is a connection between two epithelium-lined surfaces and commonly develops in patients with abscesses. Other cause... Pilonidal Disease Foundations Management Hidradenitis Suppurativa Foundations Clinical Findings Differential Diagnosis Management Proctalgia Levator Ani Syndrome Proctalgia Fugax Fecal Incontinence Foundations Clinical Features Management Pruritis Ani Foundations Diagnostic Testing Management Sexually Transmitted Disease and Proctitis Foundations . The gram-negative diplococcus Neisseria gonorrhoeae causes gonorrhea. Proctitis (inflammation of the rectum) results from ana... . Infection with Chlamydia trachomatis, an intracellular organism that is endemic to the tropics, is a common STD in the United ... . Herpes proctitis is caused by herpes simplex virus type 1 (HSV-1) and HSV-2. Symptoms appear 1 to 3 weeks after exposure. Th... . Syphilis is caused by Treponema pallidum, a motile spirochete. During anal intercourse, the organism enters the rectal mucosa ... . Chancroid is caused by the gram-negative bacillus Haemophilus ducreyi, and begins as an inflammatory pustule or macule that r... . Condyloma acuminatum (genital warts), the most commonly encountered anorectal STD, is caused by the human papillomavirus. The ... . There is significant comorbidity between patients who are HIV seropositive and other STDs. Anorectal complaints in HIV-positi... Management Radiation Proctitis Rectal Prolapse Rectal Foreign Bodies Foundations Clinical Features Diagnostic Testing Management References 83 - Renal Failure Renal Failure Acute Kidney Injury Foundations Clinical Features Differential Diagnosis Prerenal Azotemia Postrenal (Obstructive) Acute Kidney Injury Intrinsic Acute Kidney Injury . This may represent a primary renal process or may be the manifestation of any of a wide range of other disease entities (see B... . Acute interstitial nephritis (AIN) is usually precipitated by drug exposure or by infection. Drug-induced AIN is poorly under... . This can be classified according to the size of the vessel that is affected. Disorders such as renal arterial thrombosis or em... . ATN refers to a generally reversible deterioration of kidney function associated with a variety of renal insults. Oliguria may... Diagnostic Testing Urine Volume Urinalysis . The dipstick detects free hemoglobin from lysed RBCs (or myoglobin) and the hemoglobin inside RBCs but is more sensitive to fr... . The dipstick test for protein, which uses the color change of tetrabromophenol blue, can detect protein at concentrations of 1... Serum and Urine Chemical Analysis . The normal range for the serum creatinine level extends from 0.5 mg/dL in thin people to 1.5 mg/dL in muscular persons. Spurio... . Normally, urine sodium concentration parallels sodium intake. A low urine sodium concentration thus indicates not only intact ... Renal Imaging . Noncontrast CT may be useful in evaluating some azotemic patients. Hydronephrosis can be recognized without the use of contras... . Ultrasonography is a safe and reasonably reliable method for excluding obstruction as a cause of AKI. The normal kidney shows ... Diagnosis Management Hyperkalemia and Other Metabolic Derangements . The most common metabolic cause of death in patients with AKI results from an inability to excrete endogenous and exogenous po... . Hypocalcemia is a common feature of AKI that can develop rapidly after its onset. Vitamin D–dependent intestinal absorption of... . Hyperphosphatemia resulting from decreased renal elimination of phosphate is another common feature. The serum phosphorus leve... . This may complicate AKI when patients are given magnesium-containing antacids or laxatives. Thus, these products, as well as ... . These can be expected to occur in most patients with AKI. Some nonoliguric patients excrete enough salt and water to produce i... Disposition Chronic Kidney Disease Foundations Pathophysiology Clinical Features Cardiovascular System Pulmonary Effects Neurologic Features Gastrointestinal System Dermatologic Features Musculoskeletal System Immunologic Considerations Hematologic Effects Differential Diagnosis Diagnostic Testing Management Hyperkalemia Pulmonary Edema Infection Dialysis . This requires special access to the patient’s circulation, generally through a surgically created arteriovenous fistula or an ... . In peritoneal dialysis, the patient’s peritoneum functions as the dialysis membrane. Dialysate is infused through a surgically... . The decision to initiate chronic dialysis in the patient with CKD generally is made by the patient’s nephrologist in the setti... Complications of Dialysis Hemodialysis Vascular Access–Related Complications Non–Vascular Access–Related Complications of Dialysis . Hypotension that occurs after dialysis is usually the result of an acute reduction in circulating intravascular volume and fai... . Shortness of breath in dialysis patients generally is caused by volume overload. In the patient who becomes short of breath wh... . Cardiovascular disease is a leading cause of death in patients with CKD, and most episodes of chest pain occurring during dial... . Neurologic symptoms during or immediately after hemodialysis may be caused by disequilibrium syndrome, a constellation of symp... Peritoneal Dialysis References 84 - Sexually Transmitted Infections Disorders Characterized by Genital Ulcers Herpes Background and Importance Clinical Features Diagnostic Testing Management Disposition Syphilis Background and Importance Clinical Features Diagnostic Testing Management Disposition Chancroid Background and Importance Clinical Features Diagnostic Testing Management Foundations Gonorrhea Background and Importance Clinical Features Diagnostic Testing Treatment Disposition Chlamydia Background and Importance Clinical Features Diagnostic Testing Management Disposition Nongonococcal Urethritis Trichomoniasis Background and Importance Clinical Features Diagnostic Testing Management Disposition Pelvic Inflammatory Disease Background and Importance Clinical Features Diagnostic Testing Management Disposition Bacterial Vaginosis Background and Importance Clinical Features and Diagnostic Testing Management Vulvovaginal Candidiasis Background and Importance Clinical Features and Diagnostic Testing Management Epithelial Cell Infections Condyloma Acuminata (Genital Warts) Background and Importance Clinical Findings Diagnostic Testing Management Molluscum Contagiosum Ectoparasites Pediculosis Pubis Scabies References 85 - Urologic Disorders Background Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Urinalysis and Urine Culture Imaging Management Simple Urinary Tract Infection Complex Urinary Tract Infection Disposition Pregnancy Indwelling and Temporary Urinary Catheters Prostatitis Background Clinical Features Diagnostic Testing Management Renal Calculi Background Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Urinalysis and Culture Other Laboratory Tests Imaging Radiography of the Kidney, Ureter, and Bladder Intravenous Pyelography Computed Tomography Ultrasonography Management Disposition Indications for Admission Outpatient Management Bladder (Vesical) Calculus Background Clinical Features Diagnostic Testing Management Acute Scrotal Pain Background Specific Disorders Testicular Torsion Background Clinical Features Differential Diagnosis Diagnostic Testing Urinalysis Imaging Management Disposition Torsion of Appendages of the Testis Background Clinical Features Diagnostic Testing Management and Disposition Epididymitis Background Clinical Features Diagnostic Testing Management Disposition Orchitis Background Clinical Features Diagnostic Testing Management Testicular Tumors Background Clinical Features Diagnostic Testing Management and Disposition Testicular Trauma Acute Urinary Retention Background Physiology and Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Hematuria Background Clinical Features Diagnostic Testing Management and Disposition References 86 - Gynecologic Disorders Gynecologic Disorders Adnexal Torsion Foundations Clinical Features Differential Diagnoses Diagnostic Testing Laboratory Tests Imaging Tests . Ultrasound examination is the optimal initial imaging test in the evaluation of patients with pelvic pain highly suggestive of... . When alternative abdominal pathologies are strong considerations in the differential diagnosis of a patient’s acute pelvic pai... . MRI may also demonstrate findings consistent with torsion. It is particularly helpful when the diagnosis is unclear, such as i... . Given the frequency of equivocal findings on imaging studies, the lack of reliable clinical decision tools, the absence of a p... Management and Disposition Ovarian Cysts and Masses Foundations Clinical Features Differential Diagnoses Diagnostic Testing Laboratory Tests Imaging Tests . Ultrasonography is used to diagnose and characterize all ovarian pathologic processes and lesions, including cysts and masses.... . When the differential diagnosis of unilateral pelvic pain is broad, particularly in the patient with symptoms or physical find... . MRI provides better soft tissue contrast than CT and has been shown in multiple studies to differentiate benign from malignant... Management and Disposition Foundations Clinical Features History Physical Examination Differential Diagnoses Diagnostic Strategies Laboratory Tests Imaging Tests Management Disposition Emergency Contraception References 87 - Stroke Foundations Background and Importance Ischemic Stroke Transient Ischemic Attack Hemorrhagic Stroke Anatomy, Physiology, and Pathophysiology Clinical Features Ischemic Stroke Chemoreceptor Trigger Zone for Emesis Hemorrhagic Stroke Differential Diagnoses Ischemic Stroke Hemorrhagic Stroke Diagnostic Testing Ischemic Stroke Transient Ischemic Attack Hemorrhagic Stroke Management Ischemic Stroke Blood Pressure Management Temperature Blood Glucose Reperfusion Therapy Thrombolytic Therapy Agent and Dosage Time Window Thrombolysis for Mild Disabling Versus Nondisabling Acute Ischemic Stroke Thrombolysis in Patients on Anticoagulants Before the Stroke Symptomatic Intracerebral Hemorrhage Following Thrombolysis Cerebral Microbleeds Mechanical Thrombectomy Timing Mechanical Thrombectomy and Thrombolysis Monitoring Blood Pressure Management Reversal of Anticoagulation Hemostatic Agents Seizures Prognosis Increased Intracranial Pressure Neurosurgical Intervention Transient Ischemic Attack Disposition References 88 - Seizure Background and Classification Anatomy, Physiology, and Pathophysiology Clinical Features Clinical History Physical Examination Differential Diagnosis Diagnostic Testing Laboratory Studies Radiology Special Procedures and Tests Management Stabilization and Empirical Therapy Definitive Management Special Cases Alcohol-Related Seizures Seizures Related to Other Toxins Post-Traumatic Seizures Seizures in Pregnancy First-Time Seizures Breakthrough Seizures Post-Anoxic Seizures Nonconvulsive Status Epilepticus Inflammation-Related Seizures Disposition References 89 - Headache Disorders Migraine Headache Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Cluster Headache Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Tension-Type Headache Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Secondary Headache Disorders Subarachnoid Hemorrhage Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Intracranial Neoplasm Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Giant Cell Arteritis Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Carotid and Vertebral Artery Dissection Principles Clinical Features . The classic presentation of symptoms for carotid artery dissection includes (1) unilateral headache or neck pain, sometimes ra... . Vertebral artery dissections are less common than carotid dissections. The classic presentation is that of a relatively young ... Differential Diagnoses Diagnostic Testing Management Disposition Cerebral Venous Thrombosis Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Idiopathic Intracranial Hypertension Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Post–Dural Puncture Headache and Other Low CSF Pressure Headaches Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Post-Traumatic Headache Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Hypertensive Headache Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Reversible Cerebral Vasoconstriction Syndrome Principles Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 90 - Delirium and Dementia Delirium Background Pathophysiology Clinical Features Differential Diagnosis Diagnostic Studies Management Disposition Dementia Principles Background Pathophysiology Clinical Features Differential Diagnosis Senescent Forgetfulness Delirium Depression Diagnostic Testing Cognitive Evaluation Laboratory Tests and Imaging Studies Management Disposition References 91 - Brain and Cranial Nerve Disorders Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Cerebral Venous Thrombosis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Cranial Nerve Disorders Trigeminal Neuralgia (Cranial Nerve V) Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Facial Nerve Paralysis (Cranial Nerve VII) Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Vestibular Schwannoma (Cranial Nerve VIII) Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Diabetic Cranial Mononeuropathy Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 92 - Spinal Cord Disorders Foundations Anatomy Classification of Spinal Cord Syndromes Complete (Transverse) Spinal Cord Syndrome Incomplete (Partial) Spinal Cord Lesions . Central cord syndrome is the most common of the partial cord syndromes. Because of the anatomic organization of the spinal cor... . Brown-Séquard syndrome is the result of an anatomic or functional hemisection of the spinal cord. Usually associated with pen... . Anterior cord syndrome is characterized by loss of motor function, pinprick, and light touch below the level of the lesion wit... Conus Medullaris and Cauda Equina Syndromes Clinical Features History Physical Examination Motor Function Sensory Function Reflexes Differential Diagnoses Diagnostic Testing Management Specific Disease Processes Intrinsic Cord Lesions Multiple Sclerosis Transverse Myelitis . Acute transverse myelitis (TM) refers to acute or subacute spinal cord dysfunction characterized by paraplegia, a transverse l... . In addition to motor, sensory, and urinary disturbances, patients with acute transverse myelitis may complain of back pain as ... . Considerations in the differential diagnosis for transverse myelitis include MS, SEA, spinal epidural hematoma (SEH), primary ... . MRI with gadolinium enhancement is the diagnostic modality of choice for suspected transverse myelitis (Fig. 92.4). In cases o... . Treatment is tailored to the suspected underlying etiology. There are no good studies supporting a role for steroids. The exce... Spinal Subarachnoid Hemorrhage . Intraspinal hemorrhage is rare and may occur in the same anatomic locations as intracranial hemorrhages; epidural, subdural, s... . Patients with SSAH present with excruciating back pain of a sudden and severe nature at the level of the hemorrhage. This pain... . Considerations in the differential diagnosis include disc herniation, tumor, ischemia from aortic dissection, and anterior spi... . Because bone artifact may obscure the presence of blood in the spine, the diagnostic study of choice in patients with suspecte... . The treatment of spinal subarachnoid hemorrhage depends on the etiology of the hemorrhage. Neurosurgical referral is obtained ... Syringomyelia . Syringomyelia is the presence of a cavitary lesion within the tissue of the spinal cord. The word syrinx is derived from the G... . Headache and neck pain are the most common presenting complaints of patients with syringomyelia, followed by sensory disturban... . Considerations in the differential diagnosis for syrinx include intrinsic spinal tumor, demyelination, and trauma resulting in... . Syringomyelia is best seen on MRI (Fig. 92.5). No other modality currently in widespread use is equivalent in diagnostic abili... . When the diagnosis of syringomyelia is considered, emergent imaging in the ED may not be necessary if follow-up evaluation ca... Human Immunodeficiency Virus Myelopathy Spinal Cord Infarction Surfer’s Myelopathy Extrinsic Cord Lesions Spinal Epidural Hematoma . Spinal epidural hematoma (SEH) is a relatively rare condition where blood accumulates in the epidural space and can cause comp... . Patients usually present with sudden, severe, constant back pain. The pain is frequently radicular and may occur after a strai... . Considerations in the differential diagnosis include SEA, epidural neoplasm, acute disc herniation, and SSAH. SEH has even bee... . MRI with and without IV contrast is the diagnostic study of choice. CT myelography will frequently pick up the hematoma or sho... . In patients with SEH, recovery without surgery is rare. Neurosurgical consultation for emergent decompressive laminectomy is i... Spinal Epidural Abscess . Spinal epidural abscess (SEA) is an infectious process usually confined to the adipose tissue of the dorsal epidural space whe... . The clinical presentation of SEA begins with back pain localized to the level of the affected spine, often associated with ten... . SEA is frequently misdiagnosed on initial presentation, especially in a patient who is neurologically intact. In someone with ... . MRI with IV contrast is the imaging modality of choice and should be performed emergently if the diagnosis of SEA is considere... . Urgent surgical consultation for possible decompression is required for SEA. Antibiotics effective against the most common pa... Discitis . Discitis is an uncommon primary infection of the vertebral disc, specifically the nucleus pulposus, with secondary involvement... . Clinical presentation can be quite variable. In general, patients present with moderate to severe pain localized to the level ... . Considerations in the differential diagnosis of discitis include vertebral osteomyelitis, spinal epidural abscess, neoplasm, a... . MRI with IV contrast is the radiographic study of choice for suspected discitis, because it not only enables diagnosis but als... . With timely diagnosis and treatment, outcome is usually very good and medical treatment with IV antibiotics that cover Staphyl... Neoplasm . Spinal cord tumors are classified according to their relationship to the dura and spinal cord (extradural, intradural extramed... . In nearly all patients with spinal neoplasm, the initial complaint is pain, either in the back at the level of the tumor or in... . Considerations in the differential diagnosis of spinal neoplasm include any of the compressive lesions (e.g., hematoma, infect... . Patients presenting with new back pain (<6 weeks) and no risk factors or neurologic deficits on examination generally do not r... . Acute compressive myelopathy from neoplasm constitutes an oncologic emergency. Immediate treatment is required to preserve fun... Autonomic Dysreflexia Foundations Clinical Features Management Spasticity Infection References 93 - Peripheral Nerve Disorders Principles Differential Diagnosis Diagnostic Testing Specific Types of Neuropathies Type 1: Demyelinating Polyneuropathy (Guillain-Barré Syndrome) Principles Clinical Features Diagnostic Testing Management Disposition Type 2: Distal Symmetrical Polyneuropathy Principles Clinical Findings Differential Diagnosis Diagnostic Testing Management Type 4: Isolated Mononeuropathies Radial Mononeuropathy . The radial nerve arises from the C5 to T1 roots. After exiting the brachial plexus, it passes behind the proximal humerus in t... . Because innervation of the wrist and finger extensors occurs distal to this area of the humeral shaft, findings are characteri... . There exists no diagnostic test per se for this disease entity beyond the physical examination. EMG testing is employed to aid... . While patients are waiting for spontaneous recovery to occur, the hand should be maintained in about 60 degrees of dorsiflexio... Ulnar Mononeuropathy . The ulnar nerve includes C7 to T1 roots and passes through the brachial plexus to descend medially, without branching, to the ... . There exists no true diagnostic entity for this disease process beyond the physical examination . Most ulnar mononeuropathies will spontaneously resolve. The evidence and options for nonoperative management are limited, but ... Median Mononeuropathy . The median nerve arises from the C5 to T1 spinal nerve roots and exits the brachial plexus through the lower trunk (Fig. 93.6)... . Although the patient may complain of bilateral symptoms, a careful history usually reveals that symptoms in one hand preceded ... . The Tinel sign (percussion of the median nerve at the wrist) and Phalen sign (maximal palmar flexion at the wrist) are provoca... . There are a variety of nonsurgical treatments, with splinting and steroid injections being the most common. A neutral wrist sp... Sciatic Mononeuropathy . The sciatic nerve includes L4 to S3 spinal nerve roots that pass through the lumbosacral plexus and divides into two terminal ... . Ambulation is extremely difficult because of inability to flex the knee and a flail foot (i.e., neither flexion nor extension ... . This condition is mainly diagnosed by physical findings. If used, electrophysiologic studies show evidence of involvement of g... . Treatment of footdrop requires a posterior splint to maintain the ankle at 90 degrees until a brace can be obtained (see the C... Lateral Femoral Cutaneous Mononeuropathy . Lateral femoral cutaneous mononeuropathy (meralgia paresthetica) is a common syndrome believed to be caused by injury to this ... . Numbness and dysesthesia over the skin of the upper lateral thigh is typically found on physical examination . There is no diagnostic test for this disease process beyond the physical examination . Resolution usually occurs spontaneously. In select patients, such as obese patients with BMI of 30 or greater, recommendations... Common Peroneal Mononeuropathy . The common peroneal nerve is a continuation of one trunk of the sciatic nerve. It is most vulnerable to injury where it winds ... . The most striking feature of a complete common peroneal mononeuropathy is footdrop caused by weakness of foot dorsiflexion. At... . Most patients with peroneal palsy recover. Those who do not should be studied electrophysiologically to ensure that the point ... . Treatment of common peroneal palsy requires a posterior splint to maintain the ankle at 90 degrees until the nerve regenerates... Type 5: Mononeuropathy Multiplex Principles Clinical Findings . The PNS manifestations of Lyme disease are divided into early and late. The early PNS syndromes commonly include facial nerve ... Diagnostic Testing Management Type 6: Amyotrophic Lateral Sclerosis Principles Clinical Findings Diagnostic Testing Management Type 7: Sensory Neuronopathy (Ganglionopathy) Principles Clinical Findings Diagnostic Testing Management References 94 - Neuromuscular Disorders Clinical Features History Physical Examination Differential Diagnosis Myelopathies Motor Neuron Disease Neuropathies Diseases of the Neuromuscular Junction Myopathies Diagnostic Testing Disorders of the Neuromuscular Junction Myasthenia Gravis Principles . Myasthenic crisis is defined as respiratory failure requiring mechanical ventilation. It occurs in 15% to 20% of patients with... . Lambert-Eaton myasthenic syndrome is a rare disorder. Almost 50% of cases are associated with small cell carcinoma of the lun... Diagnostic Testing Management Disposition Botulism Principles Clinical Features Diagnostic Testing Management Disposition Tick Paralysis Principles Clinical Features Management Disposition Disorders of the Muscles Inflammatory Disorders Principles Clinical Features Diagnostic Testing Management Disposition Metabolic Disorders Periodic Paralysis . Periodic paralysis of the hypokalemic and hyperkalemic forms is a rare hereditary disorder of ion channels resulting in interm... . Patients may suffer either isolated or recurrent episodes of flaccid paralysis. The lower limbs are involved more often than t... . The ECG may demonstrate signs of hyperkalemia or hypokalemia. ECG findings of hyperkalemia include peaked T waves, prolongatio... . Many cases resolve spontaneously with supportive care alone. The mainstay of management is the treatment of the underlying ele... . In the past, most cases of periodic paralysis required an inpatient stay, but most patients can be managed in less than 24 hou... References 95 - Central Nervous System Infections Foundations Background and Pathophysiology Bacterial Meningitis Viral Meningitis Viral Encephalitis Tuberculous Meningitis Fungal Meningitis Central Nervous System Abscess Clinical Features Meningitis Encephalitis Central Nervous System Abscess CSF Shunt Infection Differential Diagnoses Diagnostic Testing Blood Testing Neuroimaging Lumbar Puncture Opening Pressure Cerebrospinal Spinal Fluid Analysis Cerebrospinal Spinal Fluid Cell Count Gram Stain Xanthochromia Glucose Protein Other Stains Lactic Acid Antigen Detection Bacterial Cultures Additional Investigations Management Bacterial Meningitis Tuberculous Meningitis Fungal Meningitis Viral Meningitis Viral Encephalitis Central Nervous System Abscess CSF Shunt Infection Chemoprophylaxis Immunoprophylaxis Disposition References 96 - Thought Disorders Background and Importance Pathophysiology Clinical Features Differential Diagnoses Medical Disorders Psychiatric Disorders Diagnostic Testing Management Disposition References 97 - Mood Disorders Foundations Background and Importance Epidemiology Neuroanatomy Pathophysiology Neurophysiology Endocrine System Genetics Psychosocial Factors Clinical Features Major Depressive Disorder Mood Disturbances Disturbances in Psychomotor Activity Vegetative Disturbances Thought Process and Content Masked Depression Special Considerations . Criteria for depression in children and adolescents are the same as for depression in adults. Depression in these age groups c... . A newly described phenomenon for children who may have been previously diagnosed with depression or bipolar disorder is disrup... . Depression is more common in elders because of more frequent occurrences of loss, comorbid health issues, and loss of autonomy... Other Depressive Disorders Peripartum Depression Persistent Depressive Disorder Premenstrual Dysphoric Disorder Seasonal Affective Disorder Bipolar Disorders Manic Episode Cyclothymic Disorder Mood Disorders Caused by a General Medical Condition Differential Diagnoses Medical Disorders, Medications, and Substance Abuse or Withdrawal Grief and Bereavement Adjustment Disorders Borderline Personality Disorder Dementia Diagnostic Testing Management Disposition References 98 - Anxiety Disorders Background and Importance Epidemiology Pathophysiology Clinical Features Panic Disorder Generalized Anxiety Disorder Post-Traumatic Stress Disorder Specific Phobias Obsessive-Compulsive Disorder Hyperventilation Syndrome Somatic Symptoms and Related Disorders Differential Diagnosis Cardiac Diseases Endocrine Diseases Respiratory Diseases Neurologic Disorders Drug Intoxication and Withdrawal States Diagnostic Testing Management Pharmacologic Treatment Nonpharmacologic Therapy Disposition References 99 - Somatic Symptoms and Related Disorders Foundations Clinical Features Somatic Symptom Disorder Illness Anxiety Disorder Conversion Disorder Factitious Disorder Psychological Factors Affecting Medical Illness Differential Diagnoses Diagnostic Testing Management Disposition References 100 - Factitious Disorders and Malingering Clinical Features Factitious Disorders Factitious Disorders Imposed on Self . Individuals may intentionally produce or feign psychological (often psychotic) symptoms suggestive of a mental disorder. Stimu... . The intentional production of physical symptoms may take the form of fabricating symptoms without signs (e.g., feigning abdomi... . The uncommon patient with true Munchausen syndrome has a prolonged pattern of “medical imposture,” usually years in duration. ... Factitious Disorder Imposed on Another . Ninety-eight percent of perpetrators are biological mothers who come from all socioeconomic groups.7,17,18 Many have a backgr... . Victims of FDIA are equally male and female children. The proper diagnosis for the victims of FDIA is the coding for confirmed... Differential Diagnoses Diagnostic Testing Factitious Disorder Malingering Management Factitious Disorders Malingering Disposition References 101 - Suicidal Behavior Foundations Background and Importance Epidemiology Risk Factors Precipitating Factors At Risk Populations Mental Illness Alcohol and Substance Abuse Disorders Chronic Illness Pathophysiology Methods of Suicide Clinical Features Initial Recognition and Screening History and Physical Examination Differential Diagnoses Normal Colloquialisms and Expressions of Suffering Malingering Non-Suicidal Self-Injury Unintentional Injury or Ingestion Substance Intoxication, Abuse, or Misuse Suicidal Obsessions or Preoccupations Diagnostic Testing Management Overview Suicide Precautions Pharmacologic Treatment Risk Assessment Documentation Disposition Psychiatric Hospitalization Discharge Brief Patient Education Joint Safety Planning Lethal Means Restriction Counseling Referral for Outpatient Care Caring Contacts Additional Ethical Considerations Do-Not-Resuscitate Orders Physician-Assisted Dying References 102 - Arthritis General Approach to Arthritis Foundations Background Pathophysiology Clinical Features and Differential Diagnosis History Physical Examination . The initial examination should focus on the affected joint or joints and should also assess for systemic or distant findings w... . The examination of the painful joint is performed in a systematic manner following the general principle of inspection, palpat... . Begin the examination by watching the patient move in the exam room. Gait can provide important clues to discomfort and disabi... . When palpating, begin with an assessment of joint warmth. Large joints, such as the knee, should feel cool to the touch or sim... . Both active and passive ROM should be assessed and compared with the unaffected extremity whenever possible. Active ROM refers... . Strength and sensation should be assessed in the affected joint, as well as the joints directly above and below the painful ar... Diagnostic Testing Radiographic Tests . Plain radiographs or X-rays (XR) are useful in determining possible etiologies of acute arthritis. Although they are more help... . Bedside ultrasound may be used to complement the physical examination in cases of acute joint pain. The simple evaluation for ... . Advanced imaging modalities may add to the evaluation by showing the presence or absence of osteomyelitis, joint effusions, ab... Laboratory Testing Arthrocentesis and Synovial Fluid Analysis . Joint fluid aspiration with synovial fluid analysis is the most important modality used to diagnose the cause of an acutely pa... . Indications for urgent arthrocentesis include (1) to obtain joint fluid for analysis for possible infection or crystals, (2) t... . Patients should be counseled about the potential risks of the procedure, the most serious of which include inoculation of infe... . Analysis of the joint fluid obtained via arthrocentesis is a critical step in determining the cause of acute arthritis. Examin... . Visual inspection of the fluid upon aspiration can aid in diagnosis, although no findings are diagnostic without microscopic f... . The synovial WBC count is helpful in distinguishing different causes of arthritis. Although the number of WBCs is generally us... . Much like synovial WBC count and pleocytosis, increasing lactate and CRP levels in the synovial fluid correlate with an increa... . Analysis under light microscopy to evaluate for monosodium urate or calcium pyrophosphate is used to diagnose gout or pseudogo... . A positive Gram stain is diagnostic of septic arthritis though is only found in 30% to 50% of confirmed infections. A negative... Management Disposition Acute Monoarticular Joint Pain Nongonococcal Bacterial Septic Arthritis Foundations Clinical Features and Differential Diagnosis . Laboratory testing, including a serum WBC, ESR, and CRP, is commonly performed although often is of limited utility. Elevated ... Management Chronic Monoarticular Arthritis Osteoarthritis Foundations Clinical Features Diagnostic Testing Management Acute Polyarticular Joint Pain Gonococcal Arthritis Foundations Clinical Features Management Gout Foundations Clinical Features Diagnostic Testing Management Pseudogout Foundations Clinical Features Diagnostic Testing Management Lyme Disease Foundations Clinical Features Diagnostic Testing Management Acute Rheumatic Fever Foundations Clinical Features Diagnostic Testing Management Chronic Polyarthritis Rheumatoid Arthritis Foundations Clinical Features Diagnostic Testing Management Seronegative Spondyloarthropathies Foundations Ankylosing Spondylitis . Patients with AS are more likely to be male and younger (younger than 40 years of age) and often report chronic back pain with... . Acute therapies are directed at managing pain and reducing inflammation. Therefore analgesics and antiinflammatory medications... Reactive Arthritis (Formerly Termed Reiter Syndrome) . Reactive arthritis, formerly termed Reiter syndrome, generally occurs in patients 20 to 40 years of age following infection wi... . In reactive arthritis, synovial fluid demonstrates an inflammatory pattern. The joint fluid is sterile, although antigen testi... . Patients with reactive arthritis respond well to antiinflammatory treatment with NSAIDs. Antibiotics may be appropriate in pat... Psoriatic Arthritis Enteropathic Arthritis References 103 - Tendinopathy and Bursitis Foundations Background and Importance Clinical Features General Tendinopathy Specific Tendinopathies . Tendinopathies of the shoulder joint include impingement syndrome (which includes subacromial bursitis or rotator cuff tendino... . The shoulder joint is predisposed to soft tissue injury because of its extensive range of motion and unique anatomic structure... . The tendon of the long head of the biceps, given its passage between the supraspinatus and subscapularis tendons in the anteri... . Calcific tendinopathy is an acutely or chronically painful condition associated with the deposition of calcium crystals in or ... . Increasingly, athletes of all ages and skill levels are participating in sports involving overhead arm motions. Consequently, ... . Lateral epicondylitis (“tennis elbow”) is a painful elbow condition that occurs at the insertion of the common extensor tendon... . Less common than its lateral counterpart, medial epicondylitis (“pitcher’s elbow” or “golfer’s elbow”) can result from microtr... Wrist . The wrist and hand include several tendons that pass through thick, fibrous retinacular tunnels. These help to prevent subluxa... Knee . Patellar tendinopathy (“jumper’s knee”) commonly occurs in sports featuring a prominent jumping component, although it can als... Ankle . Achilles tendinopathy is a common overuse syndrome that historically was thought to affect male athletes more frequently than ... . Although rupture of the Achilles tendon most often occurs when it is preceded by tendon damage, it is possible for untrained a... Differential Diagnoses Diagnostic Testing Management General Tendinopathy Specific Tendinopathies . The treatment of rotator cuff tendinopathies and impingement syndrome follows the treatment of tendinopathy in general. Emphas... . The initial treatment of calcific tendinopathy is mainly conservative and consists of analgesia and brief immobilization (e.g.... . In up to 95% of patients, epicondylitis will improve with time and conservative therapy. Initial efforts include making the pa... . The initial treatment of de Quervain’s tenosynovitis consists of immobilization with a thumb spica splint, antiinflammatory me... . In addition to routine conservative treatment, patients with Achilles tendinopathy should be referred for orthopedic evaluatio... Disposition Bursitis Foundations Clinical Features Olecranon and Prepatellar Bursitis Subacromial Bursitis Trochanteric Bursitis Ischiogluteal Bursitis Iliopsoas Bursitis Pes Anserine Bursitis Differential Diagnoses Diagnostic Testing Management Septic Bursitis Nonseptic Bursitis Disposition References 104 - Musculoskeletal Back Pain Foundations Background Epidemiology Anatomy and Physiology Pathophysiology Nonspecific or Uncomplicated Back Pain Nerve Root Syndromes Skeletal Causes of Back Pain Clinical Features History Physical Examination Differential Diagnoses Diagnostic Testing Laboratory Testing Imaging Studies Point-of-Care Ultrasound Plain Radiographs Computed Tomography Magnetic Resonance Imaging Computed Tomography Myelogram Management Nonspecific or Uncomplicated Back Pain Disc Herniation and Nerve Root Pain Epidural Abscess and Spinal Osteomyelitis Epidural Hematoma Cauda Equina Syndrome Malignancy Fracture Disposition References 105 - Systemic Lupus Erythematosus and the Vasculitides Foundations Background and Importance Etiology and Pathophysiology Clinical Features Overview Specific Symptoms Fever Cardiopulmonary Presentations . As with other systemic inflammatory conditions, there is a significantly increased risk of coronary artery disease (CAD) in pa... . Pericarditis and effusions of the pericardium occur commonly in patients with SLE and are among the classification criteria fo... . SLE is associated with a type of noninfectious endocarditis known as Libman-Sacks endocarditis (Fig. 105.2). Mitral valve dis... . Due to disease-associated hypercoagulability, deep venous thrombosis (DVT) and pulmonary embolism (PE) are more frequent in ... . Pleuritis is the most common respiratory condition occurring in SLE. Characterized by pleuritic chest pain with or without a p... . Diseases of the lung parenchyma associated with SLE include infectious pneumonia, acute and chronic pneumonitis, interstitial ... . Shrinking lung syndrome is a rare condition associated with SLE that is characterized by symptoms of shortness of breath and p... Renal Disease Gastrointestinal Presentations Dermatologic Presentations Musculoskeletal Presentations Hematologic Disease Complications Due To Medications Differential Diagnosis Diagnostic Testing Laboratory Tests Initial Diagnosis Disease Activity Evaluation for Infection Imaging Studies Management Emergent Stabilization General Systemic Disease Activity Patients Diagnosed With Systemic Lupus Erythematosus Patients Not Diagnosed With Systemic Lupus Erythematosus Specific Presentations Infection Musculoskeletal Pain Cutaneous Manifestations Special Considerations Antiphospholipid Syndrome Foundations Clinical Features Diagnostic Testing Management Drug-Induced Lupus Disposition Vasculitis Foundations Large-Vessel Vasculitis Giant Cell Arteritis Background Clinical Features Diagnostic Testing Management Takayasu Arteritis Background Clinical Features Diagnostic Testing Management Small And Medium Vessel Vasculitis Differential Diagnosis Specific Disorders ANCA-Associated Vasculitis . GPA is a granulomatous vasculitis affecting small- and medium-sized vessels. It affects individuals in their fifth and sixth... . MPA is a non-granulomatous vasculitis affecting small- and medium-sized vessels. MPA most commonly affects patients in thei... . EGPA is an eosinophilic vasculitis of small and medium vessels.18 Mean age of the diagnosis is in the fourth and fifth decade ... Anti-Glomerular Basement Membrane Disease (Goodpasture Disease) Immune Complex Mediated Vasculitis . IgAV, formerly known as Henoch-Schonlein purpura, is a small- and medium-vessel vasculitis that is characterized by IgA depos... . Cryoglobulinemic vasculitis is characterized by a primarily small-vessel vasculitis in association with cryoglobulins in the ... Polyarteritis Nodosa Other Vasculitides . Behçet disease (BD) is a vasculitis that affects all blood vessel sizes and is characterized by the presence of recurrent oral... . Cutaneous small-vessel vasculitis (CSVV) is the most common single-organ vasculitis.24 It has been previously known as hyper... References 106 - Allergy, Anaphylaxis, and Angioedema Allergy Background and Terminology Pathophysiology Classification of Reactions Anaphylaxis Epidemiology and Risk Factors Common Triggers for Anaphylaxis Foods Drugs Insect Stings Natural Rubber Latex Radiocontrast Media Exercise-Induced Anaphylaxis Idiopathic Anaphylaxis Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Overview Positioning Epinephrine Airway Volume Expansion Antihistamines Glucocorticoids Patients Receiving Beta-Blockade Disposition Urticaria and Angioedema Diagnostic Testing Management Angioedema With Urticaria Angioedema Without Urticaria Special Considerations Disposition References 107 - Dermatologic Presentations Overview Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features and Differential Diagnoses Diagnostic Testing Management Disposition Infectious Disorders Bacterial Infections Impetigo Folliculitis Cellulitis Abscess Methicillin-Resistant Staphylococcus aureus (MRSA) Erythema Migrans Necrotizing Fasciitis Meningococcal Infection Scarlet Fever Syphilis Disseminated Gonococcal Infection Staphylococcal Scalded Skin Syndrome Toxic Shock Syndrome Rocky Mountain Spotted Fever Viral Infections Herpes Simplex Virus Varicella-Zoster Virus . Varicella, or chickenpox, is an infection caused by the varicella-zoster virus. After an incubation period of 14 to 21 days, ... . Herpes zoster, or “shingles,” is an infection caused by the varicella-zoster virus. It occurs in individuals who have previou... Viral Exanthems . Roseola infantum, otherwise known as exanthem subitum or sixth disease, is a benign illness caused by human herpesvirus 6 and ... . Measles, or rubeola, is a highly contagious viral illness spread by contact with infectious droplets, with an incubation perio... . Rubella, or German measles, is a viral illness characterized by fever, skin eruption, and generalized lymphadenopathy. It is s... . Erythema infectiosum, or “fifth disease,” is caused by parvovirus B19 infection and typically affects pediatric patients. It i... Fungal Infections Tinea Corporis Tinea Capitis Kerion Tinea Pedis Tinea Versicolor Tinea Unguium (Onychomycosis) Candidiasis . Oral candidiasis (“thrush”) is the most common clinical expressions of Candida infection. It is common in newborns with one-t... . Cutaneous candidiasis affects intertriginous areas, including the interdigital web spaces, groin, axilla, and intergluteal or ... . Vaginal candidiasis accounts for 20% to 25% of vaginitis. It has been estimated that 75% of women will experience vaginal cand... . Sporotrichosis, caused by a variety of Sporothrix species, is a fungal infection that may be transmitted by contact with soil,... Infestations Scabies Pediculosis Bed Bugs Allergic Reactions Contact Dermatitis Urticaria Poison Ivy Drug Reactions Toxic Epidermal Necrolysis Inflammatory Conditions Atopic Dermatitis Pityriasis Rosea Kawasaki Disease Erythema Multiforme Erythema Nodosum Lichen Planus Autoimmune Disorders Bullous Pemphigoid Pemphigus Vulgaris Cutaneous Malignancies References 108 - Blood and Blood Components Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Blood Banking Blood Typing . An individual blood type and screen test includes ABO grouping, Rh typing, and antibody screen for unexpected, non-ABO/Rh ant... . When a unit of blood is ordered for transfusion, a crossmatch follows the initial type and screen. In an ideal situation, bloo... . Although patients with type O blood are considered to be universal donors of packed red cells (PRBCs), whole blood from type O... Management Decision Making Pharmacology Devices and Techniques Whole Blood Packed Red Blood Cells Special Preparations of PRBCs . PRBCs can be washed to remove residual plasma and any remaining leukocytes, platelets, microaggregates, plasma proteins, and f... . A typical unit of whole blood or packed red cells can contain from 1 to 3 billion white blood cells (WBC), which can cause a v... . Blood products can be irradiated to reduce the risk for TA-GvHD in susceptible patients, which occurs in about 1 per 1 millio... . Because CMV is endemic worldwide and seropositivity rates in the United States are reported at 30% to 97%, most donated blood ... Fresh Frozen Plasma Platelets Cryoprecipitate Prothrombin Complex Concentrate Outcomes Safety and Effectiveness Massive Transfusion Protocols Acute Transfusion Reactions . The most common manifestation of a minor allergic transfusion reaction is urticaria. In some cases, however, wheezing and angi... . The reported incidence of transfusion-associated anaphylaxis is 1 in 20,000 to 50,000 transfusions, with most cases being idi... . A febrile, nonhemolytic transfusion reaction (FNHTR) is defined as a temperature elevation of 1°C (1.8°F) or higher that occur... . Intravascular hemolytic transfusion reaction is the most serious transfusion reaction. It generally results from ABO incompati... . TRALI refers to noncardiogenic pulmonary edema occurring during or shortly after the transfusion of virtually any blood produc... . Transfusion associated circulatory overload (TACO) is volume overload after transfusion that is proportional to the volume tra... Infectious Complications of Transfusions Delayed Transfusion Reactions . A delayed hemolytic transfusion reaction (DHTR) typically occurs 3 to 10 days following transfusion with blood that initially ... . This rare but typically fatal complication results when transfused lymphocytes proliferate and attack a recipient who is incap... . Rarely, profound thrombocytopenia can develop 1 to 3 weeks after a transfusion associated with an antibody response to a plate... References 109 - Anemia and Polycythemia Anemia Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Iron Deficiency Anemia Foundations Clinical Features Diagnostic Testing Management Thalassemia Foundations Pathophysiology Clinical Features Diagnostic Testing Management Sideroblastic Anemia Foundations Clinical Features Differential Diagnoses Management Anemia of Chronic Disease . Anemia of chronic disease (ACD) is secondary to reduced erythropoiesis and reduced RBC survival time in the peripheral circula... Clinical Features Diagnostic Testing Management Macrocytic and Megaloblastic Anemias Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Normochromic and Normocytic Anemias Foundations Clinical Features Diagnostic Testing Management Increased Red Blood Cell Destruction Foundations Pathophysiology Clinical Features Differential Diagnoses . Of the membrane-sustaining energy production of the erythrocyte, 85% to 90% is through the anaerobic glycolytic pathway. At l... Intrinsic Membrane Abnormality Intrinsic Hemoglobin Abnormality Extrinsic Alloantibodies Extrinsic Autoantibodies Extrinsic Mechanical Causes Environmental Causes Abnormal Sequestration Diagnostic Testing . In patients with newly diagnosed reticulocytopenia or severe hemolytic anemia, the emergency clinician may need to institute r... Sickle Cell Disease Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Polycythemia Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition References 110 - White Blood Cell Disorders Foundations Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Specific Disorders Chronic Myeloid Leukemia Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Lymphocytic Leukocytosis Foundations Clinical Features Diagnostic Testing Management Leukopenia Foundations . Signs and symptoms of neutropenia are nonspecific and may include fatigue, sweats, or weight loss. Due to the body’s inability... . Neutropenic fever, defined as a single oral temperature greater than or equal to 101°F (38.3°C) in a neutropenic patient, or g... Disposition References 111 - Disorders of Hemostasis Foundations Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Complete Blood Count and Blood Smear Platelet Count Bleeding Time and Platelet Function Assay Prothrombin Time Partial Thromboplastin Time Anti-Xa Assay Fibrinogen Thrombin Time Clot Solubility Factor Level Assays Management Thrombocytopenia Immune Thrombocytopenia Drug-Induced Thrombocytopenia . Heparin-induced thrombocytopenia (HIT) is a serious immune-mediated process associated with unfractionated heparin (UFH) an... Post-Transfusion Purpura Thrombotic Microangiopathy . TTP is most often acquired and results from autoantibodies to ADAMTS13, an endothelial protein that cleaves large vWF multimer... Dilutional Thrombocytopenia Hereditary Thrombocytopenia and Thrombocytopathy . Knowledge of abnormal platelet function as a clinical disorder has grown rapidly in recent years, with identified disorders of... . Bernard-Soulier Syndrome (BSS) results from an abnormality in the platelet gpIb complex, which allows platelet adhesion to vW... . Glanzmann thrombasthenia (GT) is a rare autosomal-recessive disorder that results from a defect in the integrin complex glyco... . Secretory defects comprise two pathologic groups: defective platelet granule formation or defective secretory machinery. These... Thrombocytosis Coagulation Disorders Hemophilia A Hemophilia B (Christmas Disease) von Willebrand Disease Miscellaneous Coagulation Disorders Medication-Induced Anticoagulation Disseminated Intravascular Coagulation Disposition References 112 - Oncologic Emergencies Foundations Febrile Neutropenia Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition REFERENCES 113 - Acid-Base Disorders Clinical Features Diagnostic Testing Basic Metabolic Panel Interpretation Five-Step Acid-Base Approach to the BMP . Check for Abnormal Values. Evaluate the BMP for any abnormalities. A low HCO3 concentration (for example, <22 mmol/L) identifi... BMP Step 2. Check the Anion Gap. The anion gap (AG) is calculated with the formula: AG = [Na+] − ([Cl−] + []). The anion gap is ... . If a Metabolic Acidosis is Present, Apply the Rule of 15. The rule of 15 is used to evaluate for concomitant respiratory acid-... . If a Wide Anion Gap Metabolic Acidosis Is Present (Anion Gap ≥15), Check the Delta Gap. Calculation of the delta gap is used t... . If a Wide Anion Gap Metabolic Acidosis Is Present (Anion Gap ≥15), But the Cause Is Not Evident, Check the Osmolar Gap. The os... Blood Gas Interpretation Three-Step Acid-Base Approach to the ABG . Determine if the Patient Is Acidemic or Alkalemic. Evaluate the pH. A pH less than 7.35 indicates acidemia; pH greater than 7.... . Determine if a Predominant Respiratory or Metabolic Acid-Base Disturbance Is Present. Evaluate Paco2 and place it into contex... . If a Predominant Respiratory Acid-Base Disturbance Is Present, Determine If There Is a Concurrent Metabolic Disturbance. Comp... Differential Diagnosis of Acid-Base Disorders Metabolic Acidosis . An elevated anion gap using the threshold of 15 mmol/L, regardless of the value of the pH or [HCO3−], indicates that a wide an... . The mnemonic HARDUP (see Box 113.3) can be used to recall the causes of a normal anion gap metabolic acidosis, which is also c... Metabolic Alkalosis . When the circulating volume is decreased, the renin-angiotensin-aldosterone system is activated, and the kidneys reabsorb fi... . Causes of metabolic alkalosis that cannot be corrected with infusion of sodium chloride containing fluids are called chloride-... Respiratory Acidosis Respiratory Alkalosis Management Intravenous Fluids Sodium Bicarbonate Therapy Disposition References Acid-Base Disorder Sample Calculations Rule of 15 Example 1 Rule of 15 Example 2 Rule of 15 Example 3 Rule of 15 Example 4 Delta Gap Example 1 Delta Gap Example 2 114 - Electrolyte Disorders Foundations Clinical Features Differential Diagnosis Diagnostic Testing Hypokalemia Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Hypernatremia Foundations Clinical Features Diagnostic Testing Management Disposition Hyponatremia Foundations Pseudohyponatremia Hypovolemic Hyponatremia Hypervolemic Hyponatremia Euvolemic Hyponatremia Clinical Features Diagnostic Testing Management Hypovolemic Hyponatremia Hypervolemic Hyponatremia Euvolemic Hyponatremia Disposition Hypercalcemia Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Hypocalcemia Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Hypermagnesemia Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Hypomagnesemia Foundations Clinical Features Differential Diagnosis Patients Maintained on Diuretics Malnourished and Alcoholic Patients Patients With Hypokalemia Patients With Acute Coronary Artery Disease and Ventricular Arrhythmias Patients Receiving Specific Medications Diagnostic Testing Management Disposition Hyperphosphatemia Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Hypophosphatemia Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition References 115 - Diabetes Mellitus and Disorders of Glucose Homeostasis Diabetes Mellitus Foundations Background and Importance Epidemiology Anatomy, Physiology, and Pathophysiology . Because plasma glucose is the predominant metabolic fuel used by the central nervous system (CNS), maintenance of the plasma g... . Insulin receptors on the beta cells of the pancreas sense elevations in the blood glucose concentration and trigger insulin re... . Maintenance of the normal plasma glucose concentration requires precise matching of glucose use with endogenous glucose produc... . Type 1 diabetes results from a chronic autoimmune process that usually exists in a preclinical state for years. The classic ma... Types of Diabetes . Type 1 diabetes is characterized by an abrupt failure of insulin production with a tendency to ketosis, even in the basal stat... . Patients with type 2 diabetes may remain asymptomatic for long periods and show low, normal, or elevated levels of insulin. Ke... . Gestational diabetes mellitus is characterized by an abnormal OGTT result that occurs during pregnancy and reverts to normal d... . Myriad causes of diabetes have been identified, including chronic pancreatitis, cystic fibrosis, genetic defects in the beta c... . Impaired glucose tolerance (IGT) has been replaced by the term prediabetes to identify individuals at high risk for the develo... Diabetes Mellitus Clinical Features Type 1 Type 2 Diabetes Mellitus Differential Diagnosis Diabetes Mellitus Diagnostic Testing Serum Glucose Level Glycosylated Hemoglobin Urine Glucose Level Urine Ketone Level Dipstick Blood Glucose Level Diabetes Mellitus Management Management of Hyperglycemia Management of Diabetes Mellitus . Goals of diabetic management include lowering the hemoglobin A1c to less than 7% and maintenance of the fasting blood sugar le... . The ADA and European Association for the Study of Diabetes have recommended lifestyle changes, including weight control, at th... . Developed in the 1940s, sulfonylureas have historically been a mainstay of oral diabetes treatment. These drugs increase insul... . Thiazolidinediones reduce insulin resistance and are especially useful in patients who require large amounts of insulin and st... . The α-glucosidase inhibitors delay intestinal monosaccharide absorption and prevent complex carbohydrate breakdown; these age... . The nonsulfonylurea secretagogues, the meglitinides, are similar to the sulfonylureas in action and mechanism. They bind to ad... . Glucagon-like peptide (GLP-1) analogs and agonists stimulate the release of insulin from pancreatic cells. Exenatide (Byetta... . Dipeptidyl peptidase-4 (DPP-4) inhibitors include sitagliptin (Januvia), saxagliptin (Onglyza), and linagliptin (Tradjenta).... . Pramlintide, administered three times daily before meals, is an amylinomimetic agent, or amylin analog, and decreases gastric ... . Dapagliflozin (Farxiga), canagliflozin (Invokana), and empagliflozin (Jardiance) are sodium-glucose cotransporter 2 (SGLT2) i... . Certain principles apply to all insulins, such as their ability to enhance gluconeogenesis and lipogenesis and suppress glycog... . Solid organ pancreas transplantation has become more common; several centers have performed combined pancreas and kidney trans... . Changes in the therapy of diabetes have recently included greater use of human insulin, which has prevented some of the advers... Late Complications of Diabetes Vascular Complications Diabetic Nephropathy Retinopathy Neuropathy The Diabetic Foot Infections Cutaneous Manifestations Skin Conditions . This is characterized by a velvety, brown-black thickening of the keratin layer, most often in the flexor surfaces. It is the... . This begins as erythematous papular or nodular lesions, usually in the pretibial area but in other areas as well. The early le... . These lesions are evidence of the hyperlipidemia associated with diabetes, similar to the xanthoma found in nondiabetic hyperl... . This is a rare occurrence. Bullae are usually filled with a clear fluid and are most often found on the extremities, especiall... . Also known as skin spots, this is the most common skin finding in diabetes. It arises as discrete, depressed, and brownish les... . Resistant, aggressive impetigo or intertrigo may suggest diabetes Diabetes Disposition Diabetic Ketoacidosis Foundations Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Management Intravenous Fluids Potassium Insulin Magnesium Sodium Bicarbonate Complications Diabetic Ketoacidosis Disposition Hyperglycemic Hyperosmolar State Foundations Pathophysiology Clinical Features Diagnostic Testing Management Intravenous Fluids Electrolytes Insulin Other Considerations Acute Complications Hyperglycemic Hyperosmolar State Disposition Diabetes in Pregnancy Hypoglycemia Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 116 - Rhabdomyolysis Background and Importance Anatomy, Physiology, and Pathophysiology Complications Early Complications . Most skeletal muscles are encased in compartments formed by bones, fascia, and other structures. The massive influx of calcium... . Potassium released from damaged muscle may lead to hyperkalemia. Over 98% of the body’s potassium is found in the intracellula... . In rhabdomyolysis, fluid moves from intravascular compartments into damaged muscle. In cases of massive muscle crush or electr... . Reversible elevations in aspartate transaminase (AST) levels may occur with rhabdomyolysis, possibly caused by myocyte release... Late Complications . Experimental evidence suggests that myoglobinuric acute renal failure is caused by myoglobin cast formation in the distal conv... . Extensive muscle damage may result in the release of prothrombotic substances, mainly thromboplastin, which activate the coagu... Differential Diagnosis Diagnostic Testing Serum Creatine Kinase Serum and Urine Myoglobin Urine Dipstick and Urinalysis Other Laboratory Findings Prognostic Tests in Rhabdomyolysis Management Fluid Replacement Mannitol and Other Diuretics Experimental Therapies Renal Replacement Therapy Disposition Prognosis References 117 - Thyroid and Adrenal Disorders Hyperthyroidism Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features History and Physical Examination Thyroid Storm Differential Diagnoses Diagnostic Testing Management Supportive Treatment Symptomatic Treatment Thyroid-Directed Treatment . Thionamides inhibit oxidation and organic binding of iodine to thyroglobulin, thereby blocking the synthesis of thyroid hormon... . Inorganic iodine blocks the release of stored thyroid hormone. Because an iodine load can increase the synthesis of thyroid ho... . Corticosteroids are capable of inhibiting the peripheral conversion of T4 to T3 and blocking the release of hormone from the t... Miscellaneous Therapies Identification and Treatment of the Precipitating Event Disposition Hypothyroidism Foundations Background and Importance Pathophysiology Clinical Features History and Physical Examination Myxedema Coma Differential Diagnoses Diagnostic Testing Management Hypothyroidism Myxedema Coma Disposition Adrenal Excess States Foundations Background and Importance Cushing Syndrome Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Hyperaldosteronism Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Pheochromocytoma and Paraganglioma Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Adrenal Insufficiency Foundations Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 118 - Bacteria DIPHTHERIA Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition PERTUSSIS Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Acute Treatment Vaccination TETANUS Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Generalized Tetanus Localized Tetanus Cephalic Tetanus Neonatal Tetanus Complications Differential Diagnoses Diagnostic Testing Management Supportive Care . Passive immunization with human tetanus immune globulin (HTIG) and active immunization with Td should be initiated as soon as ... . Toxin production is eliminated by treatment of the C. tetani infection. Wound débridement and antibiotic administration can ca... Vaccination BOTULISM Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition PNEUMOCOCCEMIA Foundations Background Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Acute Treatment Vaccination Disposition MENINGOCOCCEMIA Foundations Background Anatomy, Physiology, and Pathophysiology Clinical Features Occult Bacteremia Meningococcal Meningitis Meningococcal Septicemia Fever and a Nonblanching Rash Chronic Meningococcemia Complications Differential Diagnoses Diagnostic Testing Management Acute Treatment Antibiotic Prophylaxis and Vaccination Disposition TOXIC SHOCK SYNDROME Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition REFERENCES 119 - Viruses Foundations Mumps Clinical Features Differential Diagnosis Diagnostic Testing Management and Disposition Measles (Rubeola) Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Rubella (German Measles) Clinical Features Differential Diagnosis Diagnostic Testing Management and Disposition Viral Infections with Vesicular Rash Herpes Simplex Clinical Features . The first episode of HSV-1 infections usually occurs early in life and manifests as a gingivostomatitis and pharyngitis. Symp... . This infection is characterized by painful vesicles and ulcers on the external genitalia. The first infection is usually the m... . HSV-1 is a common cause of infectious encephalitis; it causes necrotizing hemorrhagic encephalitis, typically involving the t... . Herpes can cause a variety of cutaneous manifestations. They typically present with the classic painful grouped vesicles on an... Differential Diagnosis Diagnostic Testing Management Disposition Varicella-Zoster Virus Clinical Features . Chicken pox is a febrile illness characterized by malaise and rash. The rash begins first on the scalp and face and then sprea... . Herpes zoster typically causes a vesicular rash with an erythematous base that occurs unilaterally in a single dermatome (Fig.... Differential Diagnosis Diagnostic Testing Management . The management is mainly supportive care with antipyretics and antihistamines to decrease the pruritus caused by the skin lesi... . The goals of treatment for zoster are to treat the viral infection and control the pain that occurs with the rash. Uncomplicat... Disposition Epstein-Barr Virus Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Cytomegalovirus Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Enteroviruses Clinical Features . The poliovirus causes a nonspecific febrile illness with malaise, myalgias, headache, and sore throat. The most feared present... . Most enterovirus infections are subclinical, but they can also cause a variety of symptoms and syndromes. Enteroviruses accoun... Differential Diagnosis Diagnostic Testing Management Disposition Influenza Clinical Features Differential Diagnosis Diagnostic Testing Management . Oseltamivir, zanamivir, and peramivir are the currently available neuraminidase inhibitors. They work by inhibiting the releas... . Amantadine and rimantadine are the currently available adamantane antivirals. They prevent or greatly reduce the uncoating of ... . Baloxavir is a novel antiviral that gained US Food and Drug Administration (FDA) approval to treat influenza A and B in patien... Disposition Coronavirus Rhinovirus Clinical Features Differential Diagnosis Diagnostic Testing Management and Disposition Adenovirus Clinical Features Differential Diagnosis Diagnostic Testing Management and Disposition Parainfluenza Clinical Features Differential Diagnosis Diagnostic Testing Management Respiratory Syncytial Virus Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Viruses Associated with Diarrheal Illness Norovirus and Rotavirus Clinical Features . The disease causes a severe gastroenteritis, with vomiting, diarrhea, and abdominal cramping. In infants and children, vomitin... . The illness manifests as sudden onset of nausea, vomiting, and profuse watery diarrhea, with fever, headache, and myalgias. Th... Differential Diagnosis Diagnostic Testing Management Disposition Rabies Epidemiology Pathophysiology Clinical Features . Encephalitic rabies progresses rapidly over days, and the presenting signs and symptoms are supplanted rapidly by diffuse neur... . Paralytic rabies accounts for approximately 20% of human rabies infections. The presenting symptoms are similar to encephaliti... Differential Diagnoses Diagnostic Evaluation and Testing Management . Pasteur described the first rabies vaccine in 1885.51,52 Nerve tissue–derived vaccines similar to Pasteur’s were used worldwid... . An animal bite or potential rabies exposure is a medical urgency, not an emergency. In the emergency department, PEP is either... . All mammal bites require meticulous wound care, and if rabies prophylaxis is considered the initial wound care is critical. Ra... . PEP is almost 100% effective when administered according to CDC or WHO guidelines. Treatment failures usually occur when local... Management Disposition Arboviruses Clinical Features . The majority of people who become infected with WNV are asymptomatic. The most common presentation of symptomatic WNV is West ... . EEE virus is the most dangerous of the viruses that cause equine encephalitides. It occurs along the Gulf and Atlantic coast w... . Louis Encephalitis Virus. The majority of infections are asymptomatic, but as patients get older the rate of symptomatic infec... . The infection usually presents as fever with neurologic complaints including headache, confusion, weakness, paralysis, letharg... Differential Diagnosis Diagnostic Testing Management Disposition Other Arboviral Infections Dengue Virus . Dengue can cause a wide spectrum of disease. Many infected individuals with dengue are asymptomatic. Dengue fever is a self-l... . Other diagnoses to consider in suspected dengue patients include Zika, malaria, chikungunya, rickettsial infections, leptospir... . The diagnosis can be made via serologic testing with IgM assay, antigen testing of the viral antigen nonstructural protein 1 (... . There are no specific antiviral agents that treat dengue. The treatment is mainly supportive. Dengue fever is usually a self-... . Depending on the severity of illness, patients with dengue fever can be treated as outpatients, but some may require admission... . Zika virus is an arbovirus in the Flaviviridae family that is transmitted to humans via the Aedes species mosquitos. Although ... . The majority of patients infected with Zika virus are asymptomatic. For those who do develop symptoms, the clinical manifestat... . Other diseases with fever, rash, myalgias, and travel history should be considered, including dengue, chikungunya, malaria, ri... . The diagnosis of Zika virus infection can be made with RT-PCR or serology. In nonpregnant symptomatic patients with symptoms ... . Similar to other flavivirus infections, treatment largely consists of symptom management and supportive care. Antipyretics, an... . Chikungunya is an arbovirus in the Alphaviridae family that was originally endemic to West Africa. Since early this millennium... . Chikungunya causes a self-limiting disease very similar to dengue. Fever, myalgias, and polyarthralgias are the hallmark of t... . Other febrile illnesses with rash, myalgias, and arthralgias should be considered, including dengue, Zika, malaria, African ti... . The diagnosis can be confirmed via enzyme-linked immunosorbent assay (ELISA) testing for antibodies, RT-PCR for detecting vi... . Treatment is mainly supportive. Antipyretics, antiinflammatory agents, and analgesics play an important role in symptom contro... Viral Hemorrhagic Fevers Yellow Fever Virus Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Ebola Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Marburg Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition Lassa Fever Clinical Features Differential Diagnosis Diagnostic Testing Management Disposition References 120 - Coronaviruses Transmission Clinical Features Coronavirus Disease 2019 Multisystem Inflammatory Syndrome in Children Differential Diagnoses Diagnostic Testing Coronavirus Disease 2019 Multisystem Inflammatory Syndrome in Children Management Coronavirus Disease 2019 Oxygenation and Ventilation Intubation and Mechanical Ventilation Therapeutics . Remdesivir, an adenosine nucleotide analog active against a wide variety of RNA viruses including SARS-CoV-2, shows some pro... . Convalescent serum has been used for over a century for viral infections and even bacterial infections. Studies are underway f... . Cytokine storm may trigger severe COVID-19 morbidity. Monoclonal antibodies targeting IL-6 and other components of the infla... . Patients with COVID-19 are at risk for thrombotic complications, and those exhibiting evidence of thrombotic complications sh... Prevention and Vaccination Multisystem Inflammatory Syndrome in Children Middle East Respiratory Syndrome Disposition References 121 - HIV Background and Importance Pathophysiology Clinical Features Acute HIV Infection Chronic HIV Infection AIDS Clinical Manifestations by Organ System Cardiac Manifestations Pulmonary Manifestations Oropharyngeal and Gastrointestinal Manifestations Central Nervous System Manifestations Renal Manifestations Rheumatologic and Orthopedic Manifestations Hematologic Manifestations Cutaneous Manifestations Differential Diagnoses Initial Evaluation Diagnostic Testing HIV Testing Management Preexposure Prophylaxis Postexposure Prophylaxis ART Initiation and Linkage to Care Disposition References 122 - Parasites Foundations Malaria Background and Importance Pathophysiology Clinical Features Differential Diagnosis Diagnostic Testing Management Babesiosis Background and Importance Clinical Features Diagnostic Testing Management Schistosomiasis and Katayama Fever Background and Importance Diagnostic Testing Management Cysticercosis Background and Importance Clinical Features Diagnostic Testing Management African Trypanosomiasis Background and Importance Clinical Features Diagnostic Testing Management Toxoplasmosis Background and Importance Clinical Features Diagnostic Testing Management Eosinophilic Meningitis Parasites Associated with Fever Leishmaniasis Amebic Abscess Strongyloides Whipworm And Hookworm Tapeworm Elephantiasis Cutaneous Leishmaniasis Cutaneous Larva Migrans Swimmer’s Itch (Cercarial Dermatitis) Strongyloides Dracunculus medinensis Onchocerciasis Loiasis Toxocara canis (Dog Roundworm) Chagas Disease Diarrhea Cryptosporidium and Cyclospora Entamoeba histolytica Balantidium coli Giardia lamblia Echinococcosis Enterobius vermicularis Specific Parasitic Coinfections References 123 - Tickborne Illnesses Overview Identification of Ticks Physiology of Tick Feeding Lyme Disease Clinical Features Early Lyme Disease Acute Disseminated Infection . A relatively symptom-free interval usually occurs between early and disseminated infection; however, neurologic signs and sym... . Cardiac involvement in Lyme disease is uncommon, with an estimated incidence in untreated patients ranging from 4% to 10%. Car... . Although it is generally considered a sign of late Lyme disease, acute arthritis may begin during the acute disseminated stage... . Ocular involvement also may be seen in early disseminated disease; manifestations include conjunctivitis, keratitis, choroidit... Late Lyme Disease Differential Diagnoses Diagnostic Testing Management Early Disease Early Disseminated Infection . For patients with relatively mild symptoms (e.g., solitary facial nerve palsy with normal findings on CSF examination), doxycy... . Patients with mild cardiac conduction system involvement, such as a first-degree AV block with a PR interval less than 0.30 s... Late Infection . In established Lyme arthritis, the response to antibiotic therapy may be delayed for several weeks or months. An oral regimen ... . Patients with late neurologic disease affecting the central or peripheral nervous system should be treated with ceftriaxone (2... Lyme Disease and Pregnancy Vaccination Prophylaxis and Asymptomatic Tick Bites Southern Tick-Associated Rash Illness Relapsing Fever Clinical Features Differential Diagnoses Diagnostic Testing Management Tularemia Clinical Features Presentations . This accounts for approximately 80% of cases. Typically, a skin lesion on an extremity at the site of primary inoculation begi... . This is the second most common form. It is characterized by the development of lymphadenopathy (usually cervical) without an a... . This is seen in less than 2% of cases. It is characterized by unilateral conjunctivitis, with regional adenopathy involving pr... . This is manifested as severe exudative pharyngitis, with associated cervical lymphadenitis. It has been known to cause acute g... . This is a systemic form of the disease in which no obvious entry site can be found; it occurs in approximately 10% of cases. O... . This has symptoms similar to those of other bacterial pneumonias—fever and chills, cough (usually nonproductive), substernal b... Other Considerations Diagnostic Testing Management Rocky Mountain Spotted Fever Pathophysiology Clinical Features Cutaneous Manifestations Cardiopulmonary Manifestations Neurologic Manifestations Differential Diagnoses Diagnostic Testing Skin Biopsy Serologic Studies Isolation of Organism Management Supportive Care Antibiotics Corticosteroids Q Fever Pathophysiology Clinical Features Diagnostic Testing Management Ehrlichioses Pathophysiology Clinical Features Diagnostic Testing Management Babesiosis Pathophysiology Clinical Features Diagnostic Testing Management Colorado Tick Fever Pathophysiology Clinical Features Diagnostic Testing Management Other Tickborne Viruses Tick Paralysis Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management References 124 - Tuberculosis Foundations Background and Importance Pathophysiology Transmission Pathogenesis Stage 1 Stage 2 Stage 3 Stage 4 Clinical Features Risk Factors Physical Examination Complications of Pulmonic Tuberculosis Hemoptysis Pneumothorax Pleural Effusion Empyema Airway Tuberculosis Superinfection with Fungi Primary Tuberculous Pericarditis Differential Diagnoses Pulmonary Tuberculosis Bacterial Pneumonia Fungal and Nontuberculous Mycobacterial Infections Pneumonias in Patients with HIV Infection Cavitary Lesions Mediastinal Lymphadenopathy Extrapulmonary Tuberculosis Lymphadenitis Bone and Joint Infection Renal Disease Genital Disease Multisystem Disease Central Nervous System Disease Gastrointestinal Disease Diagnostic Testing Laboratory Tests White Cell Stimulation Tests Serology Diagnostic Imaging Primary Tuberculosis Postprimary Tuberculosis Microbiologic Testing Sputum Studies . Direct microscopic examination of a stained sputum specimen for AFB (i.e., an AFB smear) is the most rapid laboratory test wid... . Nucleic acid amplification (NAA) tests are performed on sputum and take only 24 to 48 hours to yield results. Their overall po... . Sputum culture is more sensitive than microscopy for the detection of MTB and is still considered the gold standard diagnostic... Tuberculin Skin Test Management Initial Management in the Emergency Department Hemoptysis Fever or Wasting History of Tuberculosis, Therapy Discontinued Antituberculosis Medications First-Line Agents Second-Line Agents Corticosteroids Initial Therapy Drug-Resistant Tuberculosis Multidrug-Resistant Tuberculosis Extensively Drug-Resistant Tuberculosis Vaccines for Mycobacterium tuberculosis Disposition Prevention of Transmission in the Emergency Department Early Identification Isolation and Environmental Control Personal Respiratory Protection Preventive Therapy After Inadvertent Exposure References 125 - Bone and Joint Infections Background and Importance Anatomy, Physiology, and Pathophysiology Causes and Microbiology Osteomyelitis Clinical Features History and Physical Examination Complications Clinical Subsets of Osteomyelitis . Osteomyelitis in children tends to be acute, usually arising from hematogenous seeding of bone, and can often be treated with ... . Vertebral osteomyelitis usually affects older adults and is increasing in frequency as the population ages and has more chroni... . Posttraumatic osteomyelitis is a form of osteomyelitis that results from open fractures, burns, bites, puncture wounds, and su... . Diabetic foot infections lead to osteomyelitis 20% of the time, while diabetic ulcers have underlying osteomyelitis 15% of the... . Patients with sickle cell disease (SCD) are at increased risk for hematogenous infection, including osteomyelitis, often due t... . Most chronic bone infections occur as a complication of posttraumatic infection, surgical procedures, or diabetic foot infecti... Differential Diagnoses Diagnostic Testing Laboratory Tests Diagnostic Imaging . Conventional radiography is the initial modality of choice to evaluate osseous changes and, in most cases, will be the only im... . Radionuclide skeletal scintigraphy (bone scanning) is more sensitive than plain radiography for the early diagnosis of osteomy... . Even though MRI is the best imaging modality to diagnose osteomyelitis because it can identify early changes in the bone, when... . The use of bone scans and CT for the evaluation of osseous anatomy has been decreasing as the availability and image quality o... Microbiologic Diagnosis Management Disposition Septic Arthritis Foundations Clinical Features History and Physical Examination Complications Clinical Subsets of Septic Arthritis . The human mouth is a polymicrobial environment comprised of aerobic organisms, such as Staphylococcus, oral gram-negative rod... . Septic arthritis is more common in children than in adults, and the incidence of septic arthritis is twice that of osteomyelit... . In the United States, N. gonorrhoeae is the most common cause of septic arthritis in sexually active patients. A person with g... . Lyme disease, the most common tickborne disease in the United States, is caused by infection with a spirochete, Borrelia burgd... . Infections occurring after joint replacement are a challenging and dangerous complication of arthroplasty, with rates reported... . Patients with underlying joint disease, especially rheumatoid arthritis or a crystal arthropathy, are at increased risk for se... . Septic arthritis can be particularly difficult to diagnose and treat if it occurs in fibrocartilaginous joints, such as the st... Differential Diagnoses Diagnostic Testing Serum and Urine Tests Joint Fluid Analysis Imaging Management Disposition References 126 - Skin and Soft Tissue Infections Foundations Background and Importance Anatomy and Physiology Pathophysiology Clinical Features Overview Cellulitis Clinical Features Diabetic Foot Infections Bite Wounds Water-Borne Infections Differential Diagnosis Diagnostic Testing Wound Cultures Blood Cultures Radiographic Studies Surface Thermal Imaging Management Disposition Abscess Clinical Features Differential Diagnosis and Diagnostic Testing Management Disposition Impetigo Clinical Features and Management Folliculitis Clinical Features and Management Acne Vulgaris and Hidradenitis Suppurativa (ACNE INVERSA) Clinical Features and Management Necrotizing Skin and Soft Tissue Infections Clinical Features Differential Diagnosis and Diagnostic Testing Management and Disposition Toxic Shock Syndromes Clinical Features Streptococcal Toxic Shock Syndrome Staphylococcal Toxic Shock Syndrome Staphylococcal Scalded Skin Syndrome Differential Diagnosis and Diagnostic Testing Management Disposition Other Infections With Skin Manifestations References 127 - Sepsis Syndrome Foundations Background Pathophysiology Mediators of Sepsis Organ System Dysfunction . Patients with sepsis may display neurologic impairment manifested by altered mental status and lethargy, commonly referred to ... . Cardiovascular dysfunction is common with sepsis. The cardiovascular dysfunction and failure arise from direct myocardial depr... . Involvement of the lung is often seen in the inflammatory response to infection. These effects are apparent, irrespective of t... . Splanchnic blood flow is dependent on mean arterial pressure because there is relatively little autoregulation. Therefore, hem... . An absolute or relative adrenal insufficiency is common in sepsis. Depending on the balance of circulating cytokines, augmenta... . Sepsis causes abnormalities in many parts of the coagulation system. Endotoxin, TNF-α, and IL-1 are the key mediators. Patho... Genetic Factors Clinical Features Symptoms and Signs Diagnostic Considerations Differential Diagnoses Diagnostic Testing Laboratory Testing . The white blood cell count can be an indicator of inflammation and activation of the inflammatory cascade. Leukocytosis is ass... . Electrolyte abnormalities should be identified and corrected. A low bicarbonate level suggests acidosis and inadequate perfusi... . Urinalysis is another essential laboratory test, especially in older patients with higher risk of urinary tract infection who ... . Proper blood, urine, sputum, cerebrospinal fluid, and other tissue culture samples are important in guiding therapy. Although ... Special Procedures Radiology Management Respiratory Support Cardiovascular Support Fluid Resuscitation Vasoactive Drug Therapy . Norepinephrine is predominantly α-agonist with some β1-agonism with minimal β2 activity and primarily functions to increase ... . Dopamine is the immediate precursor of norepinephrine and epinephrine. It is primarily an α-, β1-, and dopaminergic agonist.... . Vasopressin is a naturally occurring peptide that is synthesized as a large prohormone in the hypothalamus. In states of septi... . Epinephrine is a potent mixed α- and β-agonist. Epinephrine infusion is also associated with increased oxygen consumption, i... . Phenylephrine is a selective α1-agonist, increasing systemic vascular resistance without significant changes in cardiac outpu... . Dobutamine is a mixed α- and β-agonist. In dosage ranges from 2 to 28 μg/kg/min, the cardiac index is increased at the expen... Bicarbonate Antibiotics Steroid Therapy Disposition References 128 - Hypothermia, Frostbite, and Nonfreezing Cold Injuries ACCIDENTAL HYPOTHERMIA Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Temperature Regulation Cardiovascular System Central Nervous System Renal System Respiratory System Predisposing Factors . Decreased thermogenesis may be due to endocrine dysfunction, such as hypopituitarism, hypoadrenalism, or myxedema. Myxedema co... . Patients with erythrodermas, such as psoriasis, exfoliative dermatitis, ichthyosis, eczema, and burns, can have increased peri... . Thermoregulation can be impaired centrally, peripherally, or metabolically. Skull fractures, particularly basilar fractures, a... Trauma Clinical Features Differential Diagnoses Diagnostic Testing . Blood gas analyzers warm blood to 37°C (98.6°F), increasing the partial pressure of dissolved gases. This results in arterial ... . The hematocrit can be deceptively high due to decreased plasma volume. The hematocrit increases 2% for every 1°C (1.8°F) fall ... . A physiologic hypercoagulable state can occur with hypothermia and can be associated with a disseminated intravascular coagula... Imaging Management General Measures Volume Resuscitation Advanced Life Support Pharmacologic Treatment . The effects of hypothermia on the autonomic nervous system are variable. In primates, sympathetic response increases rapidly t... . Hypothermia compromises host defenses and predisposes to infection. In hypothermia, the usual signs of infection, including fe... . Cold abolishes adrenal responsiveness to adrenocorticotropic hormone (ACTH). A false diagnosis of decreased adrenal reserve is... Rewarming . Spontaneous passive external rewarming is noninvasive. It is the treatment of choice for patients with mild hypothermia when a... . Active rewarming is the direct transfer of exogenous heat to the patient. It can be accomplished by external or internal techn... . Early concern with AER was sparked after a 1961 study, in which 20 of 23 patients died. Retrospective analysis of clinical ser... . Many methods achieve active rewarming of the core. These techniques minimize the risk of rewarming collapse in patients with c... . Airway rewarming with heated humidified oxygen is a simple and inexpensive method that can be used as an adjunct to other form... . Peritoneal dialysis delivers dialysate at 40°C to 45°C (104°F to 113°F). Heat is conducted directly to intraperitoneal structu... . Heat transfer from irrigation fluids is usually limited due to the minimal surface area available for heat exchange. Gastric o... . Another active core rewarming option uses endovascular warming devices that are intended for therapeutic cooling and subsequen... . Truncal diathermy involves the conversion of energy waves into heat. Large amounts of heat can be delivered to deep tissues wi... . The four common extracorporeal techniques to rewarm blood are venovenous rewarming, hemodialysis, continuous arteriovenous (AV... Disposition FROSTBITE Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Prehospital Emergency Department . Stabilize hypothermia and other life-threatening conditions before warming frostbitten extremities.15 Do not delay treatment ... Thawing by Immersion in Warm Water . We elevate injured extremities to minimize edema formation, apply sterile dressings loosely, and handle frostbitten areas gent... Disposition NONFREEZING COLD INJURIES Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Immersion Injury Pernio Differential Diagnoses Diagnostic Testing Management Immersion Injury Pernio Disposition REFERENCES 129 - Heat Illness Heat Regulation . Temperature-sensitive structures are located peripherally in the skin and centrally in the body. However, skin temperature ch... . The central nervous system (CNS) interprets information received from the thermosensors to instruct thermoregulatory effectors... . Sweating and peripheral vasodilation are the major mechanisms whereby heat loss can be accelerated. In a warm environment, eva... Acclimatization Predisposing Factors Fever Versus Hyperthermia MINOR HEAT ILLNESSES Miliaria Rubra Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Heat Cramps Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Heat Edema Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Heat Syncope Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition MAJOR HEAT ILLNESSES Heat Exhaustion Foundations . Heat exhaustion (heat prostration) is a clinical syndrome characterized by volume depletion that occurs under conditions of he... . Water depletion heat exhaustion results from inadequate fluid replacement by individuals working in a hot environment and inca... Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Heatstroke Foundations . In the previously discussed forms of heat illness, although the body temperature rises, homeostatic thermoregulatory mechanism... . As heatstroke develops, energy will be insufficient to sustain thermoregulatory mechanisms, resulting in dramatic increases in... Clinical Features . The two forms of heatstroke, classic (epidemic) heatstroke (CHS) and exertional heatstroke (EHS), may have significantly diffe... Differential Diagnoses . These can masquerade as heatstroke. In patients with heatstroke, the spinal fluid should be clear, with occasional lymphocytic... . In patients with thyroid storm, the clinical symptoms resemble those of heatstroke. It should be suspected if the thyroid glan... . This is an important consideration, particularly anticholinergic poisoning. Differentiation may be difficult because heatstrok... . Symptoms of hyponatremia, especially exercised associated hyponatremia, can be mistaken for heat exhaustion or heat stroke. Al... . This disorder is induced by antipsychotic medications and is characterized by muscle rigidity, severe dyskinesia or akinesia, ... . This can also mimic heatstroke because of the elevated body temperature tremors, clonus, and CNS alterations that occur. Serot... Diagnostic Testing Management . Immediate cooling is the cornerstone of treatment. If heatstroke cannot be excluded, begin cooling immediately. In EHS, it is ... . Mortality correlates with the elevated temperature duration and number of dysfunctional organ systems, with an increased risk ... Disposition REFERENCES 130 - Electrical and Lightning Injuries Background and Importance Anatomy, Physiology, and Pathophysiology Electrical Injury . Joule’s law, which describes the amount of thermal energy applied to tissues from electricity, is described by the formula . Electrical sources create current that flows in one direction (direct current, DC) or alternates direction cyclically at varyi... . Resistance is the degree to which a substance resists the flow of current; when resistance goes down, current increases. Resis... . The pathway followed by electrical current determines morbidity and mortality. The entrance and exit sites of the electrical c... . The degree of tissue damage is directly proportional to the duration of exposure for all voltage levels. Exposure times greate... Lightning Injury Conducted Energy Weapons Clinical Features Electrical Injury Lightning Injury Skin . Most electrical injuries result in skin burns, which fall into one or more of four patterns (as described in Box 130.4). The r... . Roughly 90% of lightning strike victims suffer skin burns, but less than 5% are deep burns. Although the voltages involved in ... Cardiovascular . Cardiac or respiratory arrest is the most common cause of death immediately following electrical injury. High-voltage exposur... . The most severe effects of lightning strike are cardiac and respiratory arrest. The massive surge is analogous to defibrillati... Head and Neck . Ocular involvement is common following exposure to electrical current, with cataracts being the most frequent manifestation. O... . The most common ocular event after lightning strike is the development of cataracts, occurring immediately or in a delayed fas... Extremities . Neurovascular bundles have low resistance and are particularly prone to damage from electrical current. Muscle necrosis occurs... Nervous System . Electrical injury damages the central and peripheral nervous systems. The most common immediate central symptoms are altered m... . A wide variety of very serious neurologic effects follow lightning strike. Apnea, due to effects on the medullary respiratory ... Other Viscera . Extensive muscle damage may result in significant myoglobinuria, subsequent renal failure, and life-threatening hyperkalemia.... . The lungs, gastrointestinal tract, and other internal organs may suffer injury from blunt trauma or a blast effect. Strikes to... . Patients who present after receiving a CEW barb discharge may have local injury to the skin and nearby superficial structures,... Differential Diagnoses Electrical Injury Lightning Injury Diagnostic Testing Electrical Injury Lightning Injury Conducted Electrical Weapon Management Electrical Injury Lightning Injury Conducted Electrical Weapon Disposition Electrical Injury Lightning Injury Conducted Electrical Weapon References 131 - Scuba Diving and Dysbarism Foundations Background and Importance Physiology and Pathophysiology Clinical Features Disorders Related to Descent/Barotrauma Middle Ear Barotrauma External Ear Barotrauma Inner Ear Barotrauma Reverse Middle Ear Squeeze Barosinusitis Alternobaric Vertigo Facial Barotrauma or Mask Squeeze Disorders Arising at Depth Nitrogen Narcosis Oxygen Toxicity Contaminated Air Disorders Arising on Ascent Alternobaric Vertigo Barodontalgia Gastrointestinal Barotrauma Pulmonary Barotrauma Decompression Sickness Arterial Gas Embolism Pulmonary Edema Differential Diagnoses Diagnostic Testing Management Diving Disorders Requiring Recompression Therapy Diving Disorders Not Requiring Recompression Therapy External Ear Barotrauma Middle Ear Barotrauma Internal Ear Barotrauma Barosinusitis Facial Barotrauma Nitrogen Narcosis Pulmonary Barotrauma Alternobaric Vertigo Disposition References 132 - High-Altitude Medicine Background and Importance Epidemiology Definitions Environmental Considerations Anatomy, Physiology, and Pathophysiology Acclimatization Physiologic Response to Hypobaric Hypoxia Acute Mountain Sickness Clinical Features Differential Diagnoses Diagnostic Testing Management Oxygen Therapy Analgesics and Antiemetics Acetazolamide Dexamethasone Disposition Prevention High-Altitude Pulmonary Edema Clinical Features Differential Diagnoses Diagnostic Testing Ultrasonography Chest Radiographs Electrocardiogram and Echocardiogram Management Descent Oxygen Therapy Nifedipine Other Medications Disposition Prevention High-Altitude Cerebral Edema Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Special Considerations High-Altitude Retinal Hemorrhage Carbon Monoxide Poisoning Respiratory Illnesses Cardiovascular Hypertension Seizures Sickle Cell Disease Pregnancy Radial Keratotomy References 133 - Drowning Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features History and Physical Examination Prognostic Factors Differential Diagnoses Diagnostic Testing Management Disposition Preventive Efforts and Discharge Education References 134 - Radiation Injuries Background and Importance Radiation Measurements Radiation Protection Radiation Sources Anatomy, Physiology, and Pathophysiology Routes of Exposure Clinical Features Acute Radiation Syndrome Local Radiation Injury Differential Diagnoses Diagnostic Testing Management Prehospital Care Emergency Department Preparation External Contamination Internal Contamination Acute Radiation Syndrome . Colony-stimulating factors (cytokines) that induce bone marrow hematopoietic cells to proliferate may have substantial benefi... . Treatment for the gastrointestinal sub-syndrome is largely supportive with antiemetics (preferably serotonin receptor antagon... . Patients who develop signs and symptoms consistent with this sub-syndrome within the first 24 hours should be provided pallia... Local Radiation Injury Psychological Consequences Disposition Additional Resources References 135 - Care of the Poisoned Patient Clinical Features Toxicologic History and Physical Toxidromes Sympathomimetic Anticholinergic Cholinergic Sedative/Hypnotic Opioid Serotonin Syndrome Neuroleptic Malignant Syndrome Differential Diagnoses Diagnostic Testing Management Decontamination Syrup Of Ipecac Gastric Lavage Single-Dose Activated Charcoal Whole Bowel Irrigation Enhanced Elimination Multiple-Dose Activated Charcoal Serum Alkalinization Intravenous Fat Emulsion (Intralipid) Focused Therapy Toxicology Consultation Disposition References 136 - Toxic Alcohols Foundations Principles of Toxicology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Ethylene Glycol Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Isopropyl Alcohol Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Other Alcohols of Clinical Significance References 137 - Alcohol-Related Disease Clinical Features Alcohol Withdrawal Syndrome Alcohol-Related Seizures Alcohol Withdrawal Seizures Alcoholic Hallucinosis Cardiovascular Effects Pulmonary Effects Gastrointestinal and Hepatic Effects Esophagus and Stomach Gastrointestinal Bleeding Liver Damage Alcoholic Hepatitis Cirrhosis Pancreatitis and Malabsorption Neurologic Effects . A symmetric sensorimotor polyneuropathy is common with chronic alcohol abuse, usually in the lower extremities. It is thought ... . There are high rates of dementia reported in patients with AUD, and up to 25% when all types of severe cognitive impairment ar... Alcoholic Cerebellar Degeneration Infectious Disease Endocrine Effects Metabolic Effects Carbohydrates Lipids Electrolytes Alcoholic Ketoacidosis Hematologic Effects Anemia Leukocyte Abnormalities Platelet Disorders Hemostasis Oncologic Effects Hypothermia Psychiatric Effects Toxicologic Effects Disulfiram and Similar Reactions Other Considerations—Patient Groups Affected . Excessive high school and college drinking continues to be prevalent and problematic. Approximately 1.2 million youths aged 12... . Alcohol use is a growing public health concern for elderly adults. Elderly patients, meaning patients ages 65 years and older,... . There is no known safe level of alcohol consumption during pregnancy. Alcohol is a known teratogen that can impact fetal growt... Trauma Differential Diagnosis Diagnostic Testing Laboratory Tests Alcohol Screening Questionnaires Management Alcohol Withdrawal Syndrome Pharmacologic Treatment . Benzodiazepines have anticonvulsant activity, dose-dependent respiratory and cardiovascular depressive effects, and and be giv... . Haloperidol, a dopamine antagonist, can be considered in patients with major alcohol withdrawal or delirium tremens and acute ... . Patients being treated for major alcohol withdrawal may be given thiamine (100 mg IV) and magnesium (2 g IV). Although magnesi... Neurologic Examination New-Onset Seizures Prior History of Seizures During Withdrawal Abnormal Neurologic Examination . Partial seizures account for up to 50% of alcohol-related seizures. Conversely, approximately 20% of patients with partial al... . A patient currently taking antiepileptic drugs for an antecedent seizure disorder who presents with a seizure while intoxicate... Disposition Acute Intoxication Alcohol Withdrawal Seizures Psychiatric and Social Problems References 138 - Acetaminophen Clinical Features Differential Diagnoses Diagnostic Testing Risk Assessment With Acute Acetaminophen Ingestion Risk Assessment With Chronic Ingestion Risk Assessment in Pregnant Women Management Stabilization and Supportive Care Decontamination Enhanced Elimination Antidote Therapy N-Acetylcysteine Use in Pregnancy Duration of Therapy Disposition Need for Transplantation References 139 - Aspirin and Nonsteroidal Agents Principles of Toxicity Overview Epidemiology Salicylate-Containing Products Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination Enhanced Elimination Antidote Therapy Disposition Nonsteroidal Agents Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination Enhanced Elimination Antidote Therapy Disposition References 140 - Anticholinergics Principles of Toxicology Overview Clinical Features Differential Diagnoses Diagnostic Testing Laboratory Electrocardiogram Management Stabilization Decontamination Pharmacologic Intervention and Antidote Treatment Disposition Observation at Home Emergency Department Observation Hospital Admission ICU Admission Consultations References 141 - Antidepressants Principles Of Toxicity Monoamine Oxidase Inhibitors Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Tricyclic Antidepressants Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Selective Serotonin Reuptake Inhibitors Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Serotonin Modulators And Stimulators Miscellaneous Antidepressants Bupropion Trazodone Nefazodone Serotonin Syndrome Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Discontinuation Syndromes References 142 - Cardiovascular Drugs Foundations Clinical Features Pediatric Considerations Differential Diagnoses Diagnostic Testing Management Fab Fragments (DigiFab) Electrolyte Correction Atropine Pacing and Cardioversion Phenytoin and Lidocaine Extracorporeal Membrane Oxygenation Disposition Foundations Principles of Toxicity Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Hypotension, Bradycardia, and Atrioventricular Block Calcium Glucagon High-Dose Insulin Sodium Bicarbonate Vasopressors and Other Inotropes Intravenous Fat Emulsion (Intralipid) Ventricular Dysrhythmias Extracorporeal Elimination and Circulatory Assistance Pediatric Considerations Sequential Approach to Beta-Blocker Poisoning Disposition Foundations Principles of Toxicity Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Hypotension and Bradycardia Pediatric Considerations Disposition Clonidine and Other Central Alpha-2 Agonists Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Foundations Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 143 - Caustics Foundations Principles of Toxicity Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Special Cases Povidone-Iodine Phenol and Formaldehyde Hydrogen Peroxide Button Batteries References 144 - Cocaine and Other Sympathomimetics Foundations Cocaine Epidemiology Formulation Pathophysiology Amphetamine and Its Derivatives Epidemiology Methamphetamine Pathophysiology Ephedrine and Ephedra Caffeine Novel Psychoactive Substances Ecstasy Bath Salts Kratom Clinical Features Hyperthermia Hypertensive Emergencies Cardiac Dysrhythmias Cocaine Use Disorder, Stimulant Use Disorder Cardiomyopathy Washout Nontoxicologic sequelae Differential Diagnoses Diagnostic Testing Management Pharmacologic Sedation for Agitation Hyperthermia Acute Hypertensive Emergencies Dysrhythmias Hyponatremia Cocaine-Related Chest Pain Special Topics Body Packers Body Stuffers Disposition References 145 - THC and Hallucinogens Principles of Toxicity Lysergamides Tryptamines Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Dissociative Agents Principles of Toxicity Phencyclidine Ketamine Methoxetamine Dextromethorphan Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Cannabis and Synthetic Cannabinoids Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Other Agents Mescaline Nutmeg Salvia Kratom Ibogaine Isoxazole Mushrooms References 146 - Iron and Heavy Metals Iron Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination Enhanced Elimination Antidotal Therapy Disposition Lead Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination Antidotal Therapy . Treatment for lead toxicity rarely is commenced in the ED, but the decision to admit for chelation or source control may be in... . The treatment of adults with chronic poisoning is based primarily on symptoms and threshold BLLs established by workplace regu... Disposition Arsenic Foundations Clinical Features Acute Arsenic Toxicity Chronic Arsenic Toxicity Arsine Gas Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination and Enhanced Elimination Antidotal Therapy . With a confirmed history of exposure in a symptomatic patient, chelation should start as early as possible without waiting for... . Treatment of chronic arsenic toxicity should begin in a symptomatic patient after confirmation of elevated urinary arsenic lev... Disposition Mercury Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination Enhanced Elimination Antidotal Therapy Disposition References 147 - Hydrocarbons Overview Pathophysiology Pulmonary Pathophysiology Central Nervous System Pathophysiology Cardiac Pathophysiology Other Organ Systems Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 148 - Inhaled Toxins Simple Asphyxiants Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Pulmonary Irritants Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Smoke Inhalation Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Cyanide and Hydrogen Sulfide Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Hydrogen Cyanide Hydrogen Sulfide Disposition Carbon Monoxide Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 149 - Lithium Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination Enhanced Elimination Disposition References 150 - Antipsychotics Background Pathophysiology Toxicity Clinical Features Acute Overdose Acute Extrapyramidal Syndromes Tardive Syndromes Neuroleptic Malignant Syndrome Cardiovascular Toxicity Agranulocytosis Seizures Differential Diagnoses Diagnostic Testing Management General Anticholinergic Toxidrome Seizures Acute Extrapyramidal Syndromes Cardiotoxicity Neuroleptic Malignant Syndrome Disposition References 151 - Opioids Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Decontamination Enhanced Elimination Antidote Therapy Disposition Withdrawal References 152 - Pesticides Organophosphate Insecticides Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition Carbamate Insecticides Chlorinated Hydrocarbons Insecticides Foundations Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition Substituted Phenols Foundations Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition Chlorophenoxy Herbicides Foundations and Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition Bipyridyl Herbicides Foundations and Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition Pyrethrin and Pyrethroid Insecticides Foundations and Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition Glyphosate Foundations and Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition DEET Foundations and Principles of Toxicology Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition Rodenticides Foundations Principles of Toxicology Clinical Features Differential Diagnoses Diagnostic Testing Management Decontamination Stabilization and Supportive Care Enhanced Elimination Antidote Therapy Disposition References 153 - Plants, Herbal Medications, and Mushrooms Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Plant Categories Anticholinergics Foundations . Datura stramonium (Jimson weed, angel’s trumpet) (Fig. 153.1) and Atropa belladonna (deadly nightshade) are the most frequentl... . Ingestion can cause the antimuscarinic syndrome of agitation, diminished gastrointestinal (GI) motility, dry skin, flushing, h... . The differential diagnosis of antimuscarinic toxicity includes toxicity from pharmaceutical agents such as diphenhydramine, be... . Symptomatic patients with altered mental status or abnormal vital signs should have a screening ECG to assess corrected QT (QT... . Management should be focused on supportive care, including active cooling for hyperthermia and benzodiazepines for agitation. ... . Mildly symptomatic patients can be observed in the ED for 6 to 8 hours and discharged from the ED. Severely poisoned patients ... Antimitotic Toxins Foundations . Colchicum autumnale is also known as autumn crocus, meadow saffron, or wild saffron, and contains the toxic alkaloid colchicin... . The clinical course of colchicine poisoning is typically divided into three phases of illness.7 The first phase is marked by G... . Patients presenting in the first phase of illness may be misdiagnosed as having gastroenteritis or food poisoning. In the seco... . Laboratory data should include a complete blood count to assess for pancytopenia. Additional labs include serum electrolytes, ... . There is no specific therapy for colchicine poisoning, and management consists primarily of supportive care. There is no comme... . Patients presenting with GI symptoms but normal laboratory testing may be discharged home after 6 to 8 hours of hydration and ... Cardiac Glycosides Foundations . Cardiac glycosides bind to cell transmembrane Na+-K+-ATPases, which, in turn leads to a rise in intracellular Ca2+ concentr... . Similar to digoxin poisoning, patients with exposure to cardiac glycosides can present with GI symptoms, generalized weakness,... . The differential diagnoses of cardiac glycoside plant poisoning is broad and includes pharmaceutical toxicity with digoxin, ca... . Patients should have an ECG performed, and serum electrolytes should be evaluated with attention to potassium because cardiac ... . The cornerstone of therapy is digoxin-specific antibody fragments (Fab) and should be administered in any patient displaying ... . Symptomatic patients with bradycardia, hypotension, altered mental status, or hyperkalemia are admitted to a monitored setting... Other Cardiotoxic Plants Cicutoxin Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Other Toxic Plants Nicotinic toxin Raphides Toxalbumins Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Mushroom Categories Hepatotoxic Mushrooms Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Gyromitrin-containing Mushrooms Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Other Mushroom Classes Cholinergic Agonists Disulfiram Reaction-Inducing Mushrooms Hallucinogenic Mushrooms Gastrointestinal Irritants Renal Insufficiency Rhabdomyolysis-Inducing Mushrooms Herbal Medications Principles of Toxicity Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 154 - Sedative-Hypnotics Foundations Benzodiazepines Clinical Features Pharmacokinetics Differential Diagnoses Diagnostic Testing Management Stabilization and Supportive Care Antidote Therapy Disposition Benzodiazepine Withdrawal Syndrome Barbiturates Clinical Features Differential Diagnoses Diagnostic Testing Management Supportive Care and Stabilization Gastrointestinal Decontamination Enhanced Elimination Disposition Individual Medications Zolpidem, Zaleplon, and Zopiclone Eszopiclone Buspirone Flunitrazepam Chloral Hydrate Clinical Features Differential Diagnoses Management Disposition Over-The-Counter Sleep Aids Gamma-Hydroxybutyrate Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Withdrawal References 155 - Care of the Pediatric Patient Foundations Pathophysiology Temperature Regulation Airway Cardiovascular System Musculoskeletal System Immunologic System Pharmacologic Considerations Developmental Considerations Young Infants Infants (<12 Months) Toddlers (1- to 2-Year-Olds) Preschoolers (3- to 5-Year-Olds) School-Age Children Adolescents Evaluation Triage History Pediatric Assessment Triangle Appearance Work of Breathing Circulation to the Skin Length-Based Resuscitation Tape Physical Examination Specific Disorders Common Neonatal Complaints Neonatal Intensive Care Unit Graduate Children With Special Health Care Needs Child Abuse Other Considerations Consent for Emergency Care Pediatric-Ready Emergency Department Pediatric-Friendly Emergency Department References 156 - Pediatric Airway Management Background and Importance Anatomy 156 Physiology Equipment Management Decision Making Rapid Sequence Intubation Pretreatment Sedatives Neuromuscular Blocking Agents Devices and Techniques Basic Airway Management Advanced Airway Management Preparation Preoxygenation Positioning Placement of Tube Post-Intubation Management Video Laryngoscopy Airway Rescue Devices for Children Pediatric Surgical Airway Techniques Outcomes References 157 - Pediatric Sedation and Analgesia SEDATION Foundations Definitions1,2 Specific Issues Preparation Preprocedural Fasting Supplemental Oxygen and Capnography During Procedural Sedation and Analgesia Specific Medications . Propofol has several advantages for PSA; it has a rapid onset in 30-60 seconds, is short acting, and has antiemetic propertie... . Ketamine, a dissociative anesthetic, has sedative, amnestic, and analgesic properties. Ketamine maintains cardiovascular and r... . Multiple studies have dispelled the myth that ketamine increases intracranial pressure (ICP). Ketamine may even have beneficia... . Emergence reaction or recovery agitation refers to agitation (which may include floating sensation, vivid pleasant dreams, nig... . Ketamine stimulates tracheobronchial and salivary secretions. However, studies have shown that the co-administration of antic... . Vomiting with ketamine sedation in children is common.10 Vomiting usually develops during recovery, when patients are alert an... . The combination of ketamine with propofol has the potential to provide benefits of both sedatives. The combination allows for ... . Dexmedetomidine is an effective sedative, anxiolytic and analgesic that does not cause respiratory depression.13A loading dose... Nitrous Oxide Post-Sedation Monitoring Outcomes PAIN MANAGEMENT Foundations Specific Issues Pain Assessment Nonpharmacologic Techniques Pharmacologic Techniques . Used in conjunction with other methods for decreasing pain, topical anesthetics may decrease the need for systemic analgesics ... Local Anesthetics . A nerve block is regional anesthesia attained by the injection of a local anesthetic agent near a nerve, nerves, or nerve plex... . Nonopioid systemic analgesics (Table 157.5) include acetaminophen (paracetamol), which has analgesic and antipyretic effects b... . Opioids, previously termed narcotics, produce analgesia by binding to opioid receptors in the brain, brainstem, spinal cord, a... . In 2017, the Department of Health and Human Services declared a public health emergency due to the opioid crisis. Although the... . Low dose ketamine has been successfully used in adults and pediatric patients for the treatment of acute pain.27 Doses for the... . Naloxone is used for the reversal of opioids effects on the mu receptors (e.g., sedation and respiratory depression). Although... Outcomes REFERENCES 158 - Pediatric Resuscitation Foundations Pathophysiology Clinical Features Recognizing Imminent Arrest Management Compressions-Airway-Breathing . High quality compressions improve outcomes but are rarely performed. When administered appropriately, compressions generate on... . Although life-threatening airway emergencies in children are rare, most critical illness in children stems from respiratory e... Compression-Only Cardiopulmonary Resuscitation . Although ventricular fibrillation and pulseless ventricular tachycardia are rarely the presenting rhythm in children, they ari... Pharmacology . The particular site of vascular access is less important than its timely acquisition. Peripheral venous and intraosseous drug ... . There are no universal criteria to guide the termination of a pediatric resuscitation. Emergency clinicians are less comfortab... E-CPR Post-Arrest Care Blood Pressure Ventilation and Oxygenation Targeted Temperature Management Glucose Arrhythmia and Seizures Family Presence Septic Shock in the Pediatric Patient Foundations Background Pathophysiology Clinical Features Management Monitoring Response to Therapy Brief Resolved Unexplained Events Background Clinical Features Management Disposition References 159 - Neonatal Resuscitation Foundations Transition From Fetal to Extrauterine Life Specific Issues Indications for Resuscitation Hypoxia Hypothermia Hypoglycemia Hypovolemia Prematurity Meconium-Stained Amniotic Fluid Maternal Factors Infection Medications Withholding and Discontinuing Resuscitation Special Anatomic Anomalies Diaphragmatic Hernia Myelomeningocele and Omphalocele Choanal Atresia Pierre Robin Sequence Congenital Cardiac Disease Newborn Resuscitation Algorithm Preparation Dry, Warm, Stimulate, Position, Suction, and Assess Need for Further Intervention Ventilation, Oxygen, Intubation Chest Compressions Vascular Access Medications . Epinephrine is indicated for asystole and persistent bradycardia (<60 beats/min) despite effective ventilation with 100% oxyge... . When indicated, volume expansion is accomplished with packed red blood cells (Rh-negative type O blood), normal saline, or Lac... . Antibiotics are not indicated in the initial resuscitation phase but may be required once the neonate has been stabilized. Whe... . Concomitant hypoglycemia should be considered and promptly treated in a neonate requiring ongoing resuscitation. Hypoglycemia ... . Dopamine is indicated only when signs of shock (e.g., poor peripheral perfusion, weak pulses) are still present, despite adequ... Therapeutic Hypothermia Disposition Outcomes Safety Effectiveness Complications References 160 - Pediatric Trauma Foundations Anatomy and Physiology Clinical Features Initial Assessment and Primary Survey A—Airway and Cervical Spine Stabilization B—Breathing and Ventilation C—Circulation and Hemorrhage Control D—Disability Assessment E—Exposure and Environment F—Family Secondary Survey Physical Examination Pain Assessment Diagnostic Testing Laboratory Testing Radiologic Imaging Disposition Specific Injuries Head Injury Clinical Features . A concussion is a functional brain injury seen after a blow to the head or body, a fall, or another injury that “shakes” the b... . Bleeding from scalp wounds is often profuse and can lead to hemodynamic compromise in infants and small children if not quickl... . In children, skull fractures occur in many different configurations. Simple linear non-depressed fractures rarely require the... . Cerebral contusions are often the result of coup and countercoup forces and manifest as multiple microhemorrhages. Patients of... . Epidural hematomas are typically caused by bleeding from the meningeal vessels and are often associated with overlying skull f... . Subdural hematomas are often secondary to the rupture of bridging veins. Subdural hematomas most commonly occur in patients yo... Diagnostic Testing . Clinicians have historically used skull radiographs as a screen for skull fractures in young patients with scalp hematomas. Du... . Cranial CT provides substantial information but should be balanced with the risk of radiation. Substantial research has now id... Management and Disposition . Historically, children with skull fractures are routinely admitted to the hospital. However, alert children with linear, non-... . Prehospital BVM is recommended over ETI for support of ventilation and oxygenation. In the ED, ETI is performed in those with ... Vertebral and Spinal Cord Injury Foundations Clinical Features Diagnostic Testing Management Cardiothoracic Injury Foundations Diagnostic Testing . Traumatic pneumothoraces are less common in children and often associated with a hemothorax. Patients present with symptoms of... . Significant bleeding may occur as a result of injury to intercostal vessels, the internal mammary vessels, or lung parenchyma.... . Both penetrating and blunt thoracic trauma may cause pulmonary contusions, the most common thoracic injury in children. The co... . Traumatic diaphragmatic hernias are exceedingly rare. Mechanisms causing these injuries usually involve a sudden increase in i... . Although cardiac injuries following trauma are rare, cardiac contusion is the most common injury of the heart but is frequentl... Abdominal and Pelvic Injury Foundations Clinical Features Diagnostic Testing and Management . The spleen is the most commonly injured abdominal organ. Findings include left upper quadrant abdominal pain that may radiate ... . The liver is the second most commonly injured abdominal organ. Abdominal tenderness especially in the right upper quadrant sug... . Due to unique anatomic differences, the pediatric kidney is more susceptible to injury: potential remnant fetal lobules; incre... . Approximately 15% of children with intra-abdominal injuries will have gastrointestinal injuries. These injuries range from si... . Fortunately, pancreatic injury is rare, occurring in 5% of children with intra-abdominal injuries, but less than 1% of childr... . Penetrating wounds to the abdomen usually require rapid evaluation by a surgeon and consideration for operative intervention. ... . Straddle injuries occur when the child falls, striking their genitals and perineum on a hard object, most commonly bicycles an... . While pelvic fractures are less common in children than adults, pelvic avulsion fractures are significantly more common in chi... Musculoskeletal Injuries References 161 - Pediatric Fever Background Anatomy, Physiology, and Pathophysiology Clinical Features Diagnostic Testing White Blood Cell Count Inflammatory Markers Blood Culture Urinalysis and Urine Culture Lumbar Puncture Stool Studies Chest Radiography Rapid Viral Antigen Testing Management Approach to the Febrile Infant and Child Infants 0 to 28 Days Old Infants 29 to 90 Days Old Infants 3 to 36 Months Old Children 3 Years Old to Adulthood Specific Disorders Febrile Seizures Fever and Petechiae Toxic Shock Syndrome Fever in Children With an Underlying Chronic Medical Illness Oncology Patients Patients With the Acquired Immunodeficiency Syndrome Sickle Cell Disease Congenital Heart Disease Ventriculoperitoneal Shunts References 162 - Pediatric Upper Airway Obstruction and Infections Foundations Clinical Features Diagnostic Testing and Management Specific Disorders Supraglottic Airway Diseases Congenital Lesions . All infants are obligate nose breathers; they breathe nasally when the mouth is closed to allow breathing while feeding. In ch... . Macroglossia, an abnormally large tongue that protrudes posteriorly into the hypopharynx, is associated with conditions such a... . With micrognathia, an abnormally small mandible posteriorly displaces the normal-sized tongue (e.g., Pierre Robin and Treache... Pharyngitis Peritonsillar Abscess Mononucleosis Retropharyngeal Abscess . Retropharyngeal infections typically progress from cellulitis to organized phlegmon to mature abscess. Presenting symptoms may... . Careful evaluation of airway patency takes precedence in the management of a child with a presumed RPA. Examination of the pha... . The size of the abscess, degree of airway obstruction, and overall toxicity of the patient dictate management. The need for in... Ludwig’s Angina Epiglottitis . Epiglottitis is an invasive bacterial disease that causes inflammation and edema of the epiglottis, aryepiglottic folds, aryte... . Epiglottitis is classically acute in onset. It is marked by high fever, intense sore throat, toxicity, and rapid progression. ... . When epiglottitis is strongly suspected, a lateral neck radiograph can be helpful to confirm the diagnosis and should be evalu... . For the younger child, the importance of securing the airway takes precedence over diagnostic evaluation. A stable patient who... Trauma and Burns Allergic Reactions Diseases of the Larynx . Laryngomalacia is the most common cause of chronic stridor in infants and accounts for 60% to 75% of congenital laryngeal anom... Acquired lesions . Laryngeal papillomas are the most common benign laryngeal neoplasm in children and the second most common cause of hoarseness.... . The subglottic trachea is the origin of the high-pitched inspiratory sound commonly associated with upper airway obstruction.... Viral Croup . Croup (laryngotracheobronchitis) is the most common infectious cause of upper airway distress and obstruction in childhood. It... . Croup is diagnosed clinically. A 1- to 3-day prodrome of mild fever and URI symptoms is followed by a fairly abrupt onset of... . Glucocorticoids reduce symptoms, decrease the need for aerosolized epinephrine, and result in fewer readmissions to the ED and... Spasmodic or Atypical Croup Diseases of the Trachea Congenital lesions . Tracheomalacia results from abnormally soft, undeveloped supporting cartilage of the tracheal rings. Primary or congenital tra... . Tracheal stenosis is a congenital anomaly that results from complete tracheal rings. Infants have persistent stridor and respi... . Tracheal compression may also occur externally from vascular anomalies or mediastinal lesions (Fig. 162.11). A vascular ring i... . Infants with vascular rings typically present with persistent, unexplained respiratory and feeding problems. A chest radiograp... Bacterial tracheitis . Bacterial tracheitis, also referred to as bacterial laryngotracheobronchitis, pseudomembranous croup, is a serious cause of st... . The classic presentation of bacterial tracheitis is a toxic child with high fevers and rapidly worsening stridor that fails to... . The evaluation of a toxic-appearing child with bacterial tracheitis should be conducted expeditiously. Laboratory tests are n... . Severe distress may rarely require immediate intubation and suctioning in the ED, although airway management in the operating ... Foreign Bodies . Asphyxia from airway obstruction by an airway or esophageal foreign body is a common cause of death in children. Round foods (... . An upper airway foreign body can cause partial or complete obstruction. Clinical signs of complete obstruction include poor ai... . In a child with an aspirated foreign body in the upper airway, there is often no time, nor is it prudent, to perform diagnosti... . An acute obstructing upper airway foreign body requires emergent intervention with basic life support maneuvers. Choking infan... . Surgical cricothyrotomy is not generally recommended for infants and young children younger than 8 to 10 years. The anatomy ch... References 163 - Pediatric Lower Airway Obstruction Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features History Physical Examination Differential Diagnoses Diagnostic Testing Management Mild Exacerbation Moderate Exacerbation Severe Exacerbation Foundations Anatomy, Physiology, and Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing Management Prophylaxis Disposition References 164 - Pediatric Lung Disease Pneumonia Foundations Clinical Features Differential Diagnoses Bacterial Pneumonia Viral Pneumonia Mycoplasma Pneumonia Chlamydia Pneumonia Aspiration Pneumonia Pneumonia in the Immunocompromised Patient Diagnostic Testing . A chest radiograph is unnecessary in children without comorbid conditions who have no fever, tachypnea, or focal findings on a... . Recent studies have examined the utility of lung ultrasound for the diagnosis of pneumonia in children.18 Most studies use hig... . Children with pneumonia are at risk for hypoxemia and should undergo pulse oximetry to determine oxygen saturation; arterial o... Management . An infant younger than 2 months with pneumonia should usually be admitted to the hospital and monitored with continuous pulse ... . Blood and urine cultures should be obtained for infants 2 to 3 months of age. The decision to perform a lumbar puncture depend... . In an older child, pneumonia should be categorized into likely bacterial, viral, or mycoplasmal. The emergency clinician shoul... . Well-appearing children who can maintain hydration and are not in respiratory distress should be considered for outpatient ma... Pertussis Cystic Fibrosis Bronchopulmonary Dysplasia References 165 - Pediatric Cardiac Disorders Fetal and Neonatal Circulation Pathophysiology of Cardiovascular Compensatory Responses Clinical Features Pathophysiology of Cyanosis Clinical Features of Cyanosis History Chest Pain Physical Examination General Appearance and Pulses Vital Signs and Blood Pressures Cardiac Auscultation Diagnostic Testing Hyperoxia Test Laboratory Analysis Chest Radiography Electrocardiography Biochemical Markers Specific Disorders Congenital Heart Disease Foundations Clinical Features Differential Diagnosis Diagnostic Testing Management Acyanotic Congenital Heart Defect Foundations Specific Disorders . VSD is the most common congenital cardiac defect and accounts for 20% to 25% of all cases of CHD. Spontaneous closure occurs i... . Symptoms from a VSD are dependent on its size, and the degree of pulmonary vascular resistance present. Most VSDs are clinical... . The chest radiograph in children with small VSDs may be entirely normal. Cardiomegaly with increased pulmonary vascular markin... . All VSDs, regardless of the size of the defect, are at risk for bacterial endocarditis because of the high velocity of turbule... . ASDs account for 5% to 10% of all cases of CHD. The majority of infants and children with ASDs remain clinically asymptomatic ... . Large ASDs or those associated with comorbid conditions, such as bronchopulmonary dysplasia, can be manifested with symptoms o... . The chest radiographs of children with ASDs will reveal varying degrees of cardiomegaly, right atrial and right ventricular en... . Traditionally, ASDs required open heart surgery to place a patch over the septal defect. Newer therapies include septal occlus... Eisenmenger Syndrome . Eisenmenger syndrome can occur in any large left-to-right shunt defect. Left uncorrected, irreversible changes in the pulmon... Coarctation of the Aorta . Nearly 50% of patients with coarctation of the aorta also have an associated bicuspid aortic valve. The area of coarctation ca... . The severity of symptoms and age at time of presentation are dependent on the location of the coarctation, the degree of narro... . The chest radiograph will most often reveal a normal cardiac silhouette and normal pulmonary vascular markings, but notching a... . Definitive surgical repair of coarctation of the aorta involves angiography or stenting of the narrow aortic lumen; resection ... Cyanotic Congenital Heart Diseases . Cyanotic CHDs are a result of either decreased pulmonary blood flow to the lungs or right-to-left shunting of desaturated bl... Tetralogy of Fallot . Tetralogy of Fallot is the most common cause of cyanotic CHD beyond infancy. It arises from a single embryologic defect in whi... . The degree of cyanosis and the age at presentation are directly dependent on the degree of right ventricular outflow tract obs... . The chest radiograph of a patient with cyanotic Tetralogy of Fallot (see Fig. 165.4) shows decreased pulmonary vascular markin... . The overall treatment goals for tet spells are to increase the SVR, to abolish the hyperpnea, and to correct the metabolic aci... Postoperative Complications of Congenital Heart Defects Respiratory Syncytial Virus Infections in Infants and Children With Congenital Heart Defects Congestive Heart Failure Foundations Clinical Features Diagnostic Testing Management Pediatric Dysrhythmias Foundations Clinical Features Management Bradydysrhythmias . Bradycardia is defined as a heart rate that is slower than the lower limit of normal for a child’s age. Clinically significant... Tachydysrhythmias . Supraventricular tachycardia is the most common symptomatic dysrhythmia in infants and children. No cardiac abnormalities are ... . Supraventricular tachycardia is most likely with heart rates above 180 in young children and 220 in infants, without beat-to... . The emergency clinician should quickly initiate synchronized cardioversion (0.5 to 1 J/kg) for children in supraventricular ta... . Both atrial flutter and atrial fibrillation are rare in children and are usually associated with underlying heart conditions (... . The majority of children with ventricular tachycardia have an underlying condition, such as post–cardiac surgery status, myoca... Special Resuscitation Situations in Children Bacterial Endocarditis Foundations Clinical Features Diagnostic Studies Management Pericarditis Foundations Clinical Features Diagnostic Studies Management Myocarditis Foundations Clinical Features Diagnostic Testing Management Kawasaki Disease Foundations Clinical Features . The classic presentation of Kawasaki disease is a clinical diagnosis of four or more of the five criteria in a child who is fe... Differential Diagnoses Management Acute Rheumatic Fever Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Cardiac Causes of Sudden Death in Young Athletes Specific Disorders . Although there are a variety of congenital coronary artery anomalies, the most common potentially lethal lesion is the anomalo... . Clinical manifestations of the disease include tall and slender habitus, striae atrophicae, disproportionately long extremitie... . Obstructive hypertrophic cardiomyopathy involves a thickened muscular intraventricular septum that bulges into the left ventr... . Some individuals with hypertrophic cardiomyopathy have experienced previous “warning” episodes of chest pain, dyspnea, syncop... . The electrocardiographic findings in hypertrophic cardiomyopathy show left ventricular hypertrophy and left atrial enlargemen... . No pharmacologic therapy has been proven to prevent sudden death. Beta-blockers exert negative inotropic effects, attenuate a... . Both the Jervell–Lange-Nielsen (congenital deafness) and the Romano-Ward syndromes are inherited disorders characterized by ... . Symptoms in the young athlete that are suggestive of QT prolongation include exercise-induced palpitations, chest pain, synco... . Treatment of a prolonged QT interval depends on the cause. Underlying metabolic disorders should be corrected, and medications... . Commotio cordis occurs after a high-impact trauma to the chest, as in a high-speed motor vehicle collision or a baseball to ... References 166 - Pediatric Gastrointestinal Disorders Foundations Specific Disorders Neonatal Jaundice Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Hypertrophic Pyloric Stenosis Foundations Clinical Features Diagnostic Testing . Vomiting in infants is common, and the differential diagnosis is broad. Usually, infants present early in the disease progress... Management Disposition Malrotation with Midgut Volvulus Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition Necrotizing Enterocolitis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Gastroesophageal Reflux Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Intussusception Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Hirschsprung Disease Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Meckel Diverticulum Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Henoch-Schönlein Purpura Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Inflammatory Bowel Disease Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition Gastrointestinal Foreign Bodies Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition Appendicitis Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition Pancreatitis Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition Biliary Tract Disease Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition References 167 - Pediatric Infectious Diarrheal Disease and Dehydration Foundations Background and Importance Anatomy, Physiology, and Pathophysiology Clinical Features Specific Etiologies . In the United States and Europe, the majority of cases of diarrhea are caused by viral pathogens, with incidence peaking in th... . The common bacterial organisms causing acute diarrhea in U.S. children along with their presentations and associated character... . Protozoa can also cause diarrhea in children but are responsible for less than 1% of all cases of acute infectious diarrhea in... Complications Diagnostic Strategies Differential Diagnoses Management Disposition Dehydration Foundations Anatomy and Physiology Pathophysiology Clinical Features Diagnostic Strategies Differential Diagnoses Management Oral Rehydration Therapy Intravenous Therapy . Rapid reexpansion of the intravascular space is the goal of immediate resuscitation and can be achieved with an isotonic cryst... . Appropriate fluid therapy for the patient should be determined after initial resuscitation. Some patients may tolerate ORT; ot... . IV rehydration can lead to hyponatremia in children. This rare complication can lead to significant neurologic morbidity, incl... Disposition References 168 - Pediatric Genitourinary and Renal Tract Disorders Specific Disorders Priapism Foundations Clinical Features Differential Diagnoses Management Disposition Phimosis Foundations Diagnostic Testing Management Disposition Paraphimosis Foundations Clinical Features Diagnostic Testing Management Disposition Balanoposthitis Foundations Clinical Features and Diagnostic Testing Management Disposition Complications of Circumcisions Foundations Management Penile Entrapment and Tourniquet Injuries Foundations Clinical Features and Diagnostic Testing Management Disposition Epididymitis and Orchitis Foundations Clinical Features Diagnostic Testing Management Disposition Testicular Torsion Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Varicocele and Hydrocele Foundations Clinical Features Diagnostic Testing Management and Disposition Acute Idiopathic Scrotal Edema Foundations Clinical Features and Diagnostic Testing Management Inguinal Hernia Foundations Clinical Features Differential Diagnoses Management and Disposition Testicular Carcinoma/Tumors Foundations Clinical Features Diagnostic Testing and Management Urinary Tract Infections Foundations Clinical Features Differential Diagnoses Diagnostic Testing and Management Hematuria Foundations Nephrolithiasis Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Renal Tumors Foundations Clinical Features Diagnostic Testing Management and Disposition Proteinuria Foundations Clinical Features Diagnostic Testing and Management Disposition Poststreptococcal Glomerulonephritis (PSGN) Foundations Clinical Features Diagnostic Testing Management Nephrotic Syndrome Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition Acute Kidney Injury Foundations Clinical Features and Differential Diagnoses Diagnostic Testing Management Disposition Hypertension Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Henoch-Schönlein Purpura Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Hemolytic Uremic Syndrome Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition References 169 - Pediatric Neurologic Disorders Seizures Foundations Clinical Features Generalized Seizures Focal Onset Differential Diagnoses Management Status Epilepticus Febrile Seizures Afebrile Seizures Neonatal Seizures Disposition Anticonvulsant Therapy at Discharge Altered Mental Status Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Headaches Foundations Clinical Features Differential Diagnoses Acute Headache Chronic Progressive Headache Migraine Headache Chronic Nonprogressive Headache Cluster Headache Diagnostic Testing Management Disposition Pediatric Ataxia Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Disposition Pediatric Vertigo Foundations Clinical Features Diagnostic Testing Differential Diagnoses Management Disposition Motor Dysfunction Stroke Foundations Clinical Features Diagnostic Testing Management Disorders of the Spinal Cord Foundations Clinical Features Diagnostic Testing Management and Disposition Guillain-Barré Syndrome Foundations Clinical Features Diagnostic Testing Management and Disposition Infant Botulism Foundations Clinical Features Diagnostic Testing Management and Disposition Myasthenia Gravis Foundations Clinical Features Diagnostic Testing Management and Disposition References 170 - Pediatric Musculoskeletal Disorders Anatomy and Physiology Fracture Patterns Specific Disorders Clavicle Fracture Supracondylar Fractures of the Humerus Monteggia and Galeazzi Fracture-Dislocations Nursemaid’s Elbow Toddler’s Fracture Nonaccidental Trauma Developmental Dysplasia of the Hip Foundations Clinical Features Diagnostic Testing Management Pediatric Hip Pain Transient Synovitis Acute Septic Arthritis Legg-Calvé-Perthes Disease Slipped Capital Femoral Epiphysis Lyme Arthritis Apophyseal Injuries Osgood-Schlatter Syndrome Sever Disease Little League Elbow Apophysitis and Avulsion Fractures of the Hip Gymnast Wrist References 171 - Pediatric Drug Therapy Absorption Distribution Metabolism Elimination Other Considerations Drug Therapy in the Neonate Use of Antipyretics in Children Over-the-Counter Cough and Cold Medications Opioid Analgesics Medication Safety and Adverse Drug Events References 172 - Child Abuse Physical Abuse Foundations Role of the Emergency Clinician Clinical Features Social and Demographic Risk Factors History Physical Examination Sentinel Injuries Universal Screening Differential Diagnoses Diagnostic Testing Skeletal Survey Retinal Examination Abdominal Injury Testing Toxicology Testing Management Household Contacts Timing Mandated Reporting Disposition Sexual Abuse Foundations Trafficking Clinical Features History Physical Examination Differential Diagnoses Diagnostic Testing Management Disposition References 173 - Complications of Pregnancy Problems in Early Pregnancy Pathophysiology Terminology Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition . After assessment of hemodynamic status and management of blood loss, a patient with a threatened miscarriage requires very lit... . Treatment of the patient with incomplete miscarriage includes expectant management, medical management, or surgical evacuation... . Management of patients with presumed completed miscarriage is more complicated. If the patient brings passed tissue with her, ... Foundations Pathophysiology Clinical Features Differential Diagnoses Diagnostic Testing . Ultrasonography is the primary method used to locate early gestation, establish gestational age, and assess fetal viability. T... . Quantitative hCG levels serve two primary functions—serial levels can be used in the stable patient who can be observed as an ... . Dilation and evacuation can be used in patients without a viable IUP or ectopic pregnancy on ultrasonography to differentiate ... Management and Disposition . Approximately 20% of women with ectopic pregnancies manifest signs and symptoms warranting immediate intervention. This includ... . In stable patients with first-trimester bleeding, the goal is to exclude ectopic pregnancy in a timely manner. In the patient... Molar Pregnancy Foundations Clinical Findings Diagnostic Tests Management Complications of Late Pregnancy Vaginal Bleeding in Later Pregnancy Foundations Abruptio Placentae . Abruptio placentae is a separation of the placenta from the uterine wall and complicates roughly 1% of pregnancies. Small subc... . Vaginal bleeding occurs in 70% of patients with abruptio placentae. Blood is characteristically dark and the amount is often i... . The main alternative diagnosis in the woman with late-pregnancy bleeding is placenta previa, which is usually associated with... Placenta Previa . Placenta previa, or implantation of the placenta over the cervical os, is the other major cause of bleeding episodes during th... . Painless, fresh vaginal bleeding is the most common symptom of placenta previa. In approximately 20% of cases, some degree of ... . Ultrasonography is the diagnostic procedure of choice for localization of the placenta and diagnosis of placenta previa. Accur... . Patients who experience vaginal bleeding during late pregnancy require immediate obstetric consultation and arrangements for s... Foundations Pathophysiology Clinical Features . The patient with gestational hypertension has mild systolic or diastolic blood pressure elevation, no proteinuria, and no evid... Complications Differential Diagnoses Diagnostic Testing Management . The management of patients with mild preeclampsia includes documentation of blood pressure, reflexes, weight, and blood testin... . Hospitalization is recommended for patients with sustained hypertension above 140/90 mm Hg and signs of severe preeclampsia. B... Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management Abdominal Pain Appendicitis . Appendicitis is the most common surgical emergency in pregnant patients. The incidence of appendicitis in pregnant patients is... . The gastrointestinal symptoms of appendicitis, such as anorexia, nausea, and vomiting, mimic those of pregnancy, particularly ... . Pyelonephritis, cholecystitis, nephrolithiasis, and pregnancy-related diseases such as ectopic pregnancy, round ligament pain... . Leukocytosis is common in pregnant patients with appendicitis, although it is rarely high enough to distinguish it from the ph... . The pregnant patient with suspected appendicitis should be hospitalized after consultation with a surgeon and obstetrician. Ul... Gallbladder Disease Foundations Clinical Features Differential Diagnoses Diagnostic Testing Management and Disposition Liver Disorders Foundations Hepatitis Acute Fatty Liver . Acute fatty liver of pregnancy is a disorder of the third trimester that can result in hepatic failure, complicated labor, and... . Nausea and vomiting associated with malaise or jaundice during the third trimester should trigger consideration of a diagnosis... . Liver tenderness and coagulopathy usually suggest preeclampsia during the third trimester. Jaundice and increases in the ALT l... . Typically, leukocytosis is present, the platelet count and fibrinogen level are low, prothrombin and partial thromboplastin ti... . The patient with acute fatty liver of pregnancy may require acute stabilization for seizures or coma. Hypoglycemia may occur, ... Intrahepatic Cholestasis . Intrahepatic cholestasis of pregnancy, also termed idiopathic jaundice of pregnancy, icterus gravidarum, or pruritus gravidaru... . Generalized pruritus and mild jaundice are the hallmarks of intrahepatic cholestasis of pregnancy. However, only 20% of patien... . Exclusion of more serious entities, such as viral hepatitis, acute fatty liver, drug-induced cholestasis, and complicated cho... Normal Pregnancy Hyperemesis Gravidarum . Hyperemesis gravidarum occurs in approximately 1% of pregnant patients and is defined by nausea and vomiting that cause starva... . Laboratory studies should assess volume status and reversible electrolyte abnormalities. A urinalysis screens for the presence... . Initial management of hyperemesis involves rehydration with IV fluids (2 L of Ringer lactate [LR] at a rate of 500 ml/h), anti... Foundations Clinical Features Diagnostic Testing . Because of its widespread availability and avoidance of radiation, Doppler ultrasonography is the first-line test for the dia... . Currently, studies do not support the use of D-dimer tests in pregnancy to exclude the diagnosis of PE because this test may ... Management and Disposition Urinary Tract Infection . Asymptomatic bacteriuria in pregnancy predisposes the patient to the development of symptomatic lower and upper tract genitour... . The pregnant patient who presents with lower urinary tract symptoms (e.g., dysuria, frequency, urgency) or upper tract symptom... . Vaginitis, herpes genitalis, chlamydial infection of the urethra, and ovarian torsion can masquerade as urinary tract symptoms... . Patients with asymptomatic bacteriuria or lower urinary tract signs and symptoms should be treated with 7 to 10 days of an ant... Vaginitis . Bacterial vaginosis (formerly known as Gardnerella vaginitis or Haemophilus vaginalis vaginitis) is an overgrowth of multiple ... . The incidence of vulvovaginal candidiasis is increased during pregnancy by high levels of estrogen and other steroids. There i... . Trichomoniasis is a sexually transmitted vaginitis caused by a protozoan parasite, Trichomonas vaginalis. Of patients who have... Sexually Transmitted Disease . Chlamydia trachomatis infection is the most common sexually transmitted disease in the United States and worldwide. Its preval... . Gonococcal infection of the cervix occurs in 1% of pregnant women.30 Symptoms are similar to those in nonpregnant women. Salpi... . Herpes simplex virus (HSV) infections pose a risk in pregnancy to the mother and newborn. Women who have genital herpes during... Upper Genital Tract Infection . PID is very rare in pregnancy and does not occur after the first trimester. The differential diagnosis includes ectopic pregna... . Chorioamnionitis is the infection or inflammation of the placenta and fetal membranes. After 16 weeks of pregnancy, the chorio... Endocrine Disorders Thyroid Disorders . Thyroid disorders are common in women of childbearing age. During pregnancy, however, this is associated with a range of adver... . The diagnosis of thyroid dysfunction during pregnancy is difficult because pregnancy itself can mimic the findings in mild to ... . Thyroid dysfunction should be considered in the patient with nonspecific symptoms, including fatigue, anxiety, depression, and... . Normal values of thyroid hormones vary based on stage of pregnancy. The diagnosis of hyperthyroidism is confirmed by a low (<0... . Generally, no treatment is required for hCG-mediated hyperthyroidism. Treatment of pregnant women with overt hyperthyroidism ... Disorders of the Hypothalamic-Pituitary Axis . The pituitary gland is normally enlarged in pregnancy due to estrogen stimulation. Disorders of the hypothalamic-pituitary ax... . Disorders of the hypothalamic-pituitary axis usually present as an insidious set of chronic symptoms, many of which can mimic... . Diagnostic considerations vary according to the patient’s presentation. Growth hormone levels are elevated in patients with ac... . Stabilization consists of treatment of serious manifestations, such as hyperkalemia, tachycardia, and hypotension. Outpatient ... Acknowledgment References 174 - Medical Emergencies During Pregnancy Foundations Asthma Cardiovascular Disorders Foundations Hypertension Chronic Hypertension Hypertensive Emergencies Cardiac Disorders Acute Coronary Syndromes Valvular Heart Disease and Pulmonary Hypertension . Valvular heart disease, including both native and mechanical valves, can lead to acute heart failure during pregnancy and is a... . Pregnancy is poorly tolerated by patients with pulmonary hypertension because the pulmonary circulation cannot cope with the i... . Mitral stenosis is the most commonly encountered valvular lesion in pregnancy but is typically well tolerated except in modera... . Mitral valve prolapse is the most common cause of mitral regurgitation in developed countries, whereas rheumatic heart disease... . Symptomatic aortic stenosis during pregnancy usually occurs in the setting of a congenital bicuspid valve and patients with se... . Pregnant women with mechanical heart valves are classified as high risk with a World Health Organization (WHO) risk classifica... Hematologic Disorders Anemia Dilutional Anemia Iron Deficiency Anemia Folate Deficiency Sickle Cell Anemia Neurologic Disorders Epilepsy Multiple Sclerosis Spinal Cord Injury Myasthenia Gravis Renal Disorders Metabolic and Endocrine Disorders Diabetes General Management Hyperglycemic Hypoglycemia Fetal Effects Obesity Thyroid Disorders Hyperthyroidism Hypothyroidism Adrenal Insufficiency Electrolyte Abnormalities Systemic Infections Human Immunodeficiency Virus Infection Tuberculosis Syphilis Viral Hepatitis Hepatitis B Hepatitis C Inflammatory Disorders Systemic Lupus Erythematosus Psychiatric Disorders Schizophrenia, Bipolar Disorder, and Depression Eating Disorders Substance Dependence/Use Disorder Alcohol Smoking Cannabis Cocaine and Methamphetamines Opioids References 175 - Drug Therapy in Pregnancy Foundations Classification of Teratogenic Risk Drug Transfer Across the Placenta Drug Transfer During Lactation Drug Therapy During Pregnancy Pharmacologic Therapy Analgesic Agents Acetaminophen Nonsteroidal Antiinflammatory Drugs Aspirin Opiate Analgesics Rapid Sequence Intubation Agents Anticoagulants Thrombolytic Agents Antidotes N-Acetylcysteine Deferoxamine Digoxin Immune Fragment Dimercaprol Flumazenil Fomepizole Hydroxycobalamin Methylene Blue Naloxone Physostigmine Pralidoxime Pyridoxine Dimercaptosuccinic Acid (Succimer) Antiinfective Agents Antibiotics Aminoglycosides Cephalosporins Chloramphenicol Clindamycin Fluoroquinolones Linezolid Macrolides Metronidazole Nitrofurantoin Penicillins Sulfonamides Tetracyclines Vancomycin Antifungals Antituberculous Agents Antiviral Agents Antiherpetic Drugs Antiinfluenza Drugs Anti-HIV Drugs Cardiovascular Agents Antidysrhythmics . Adenosine has been used safely throughout pregnancy and is the drug of choice for termination of maternal supraventricular tac... . Amiodarone contains large amounts of iodine and is associated with congenital goiter and transient neonatal hyperthyroidism an... . Digoxin and quinidine are considered safe for use during pregnancy and lactation. Neither has been linked to congenital defect... . Lidocaine rapidly crosses the placenta and becomes ion-trapped in the fetus. There is no evidence of a link between the use o... . Procainamide has been safely used in the treatment of stable, wide-complex tachydysrhythmias during pregnancy. It is not asso... . Flecainide has been used safely to terminate maternal and fetal tachycardia, but it is associated with fetal hyperbilirubinemi... . There are only a few case reports of the successful and safe use of ibutilide during the latter part of pregnancy in humans. I... . Sotalol has been used in pregnant women to treat atrial arrhythmias successfully and safely, as well as hypertension. It has a... Antihypertensives . Angiotensin-converting enzyme (ACE) inhibitors are contraindicated for use during pregnancy. Furthermore, ACE inhibitors are ... . Angiotensin II receptor antagonists should be avoided during pregnancy because their use has been reported to result in fetal ... . Beta blockers are a first-line treatment of hypertension in pregnancy.15 They have not been associated with fetal malformatio... . Calcium channel blockers are effective treatments for hypertension and the termination of supraventricular rhythm disturbances... Diuretics . Nitroglycerin has not been shown to cause fetal harm in animal studies. Limited reports in humans have not shown any major eff... . Clonidine has been safely used throughout pregnancy, but experience during the first trimester remains limited. It does not ap... . Hydralazine use is associated with higher rates of maternal hypotension, placental abruption, and neonatal distress compared w... . Methyldopa has been safely used throughout pregnancy, and most reviews have not linked it to any teratogenic effects on the of... Vasopressors Endocrine Agents Diabetes Medications Thyroid Medications Gastrointestinal Agents Antacids . None of the H2 receptor antagonists has been linked to congenital malformation, and they all appear to be safe for the nursing... . Studies on proton pump inhibitor (PPI) use in pregnancy are limited but several studies and a meta-analysis have found no ass... Antiemetic Medications . Pyridoxine is used alone, or in combination with doxylamine, an antihistamine, for the treatment of nausea and vomiting of pre... . Phenothiazines, such as metoclopramide, prochlorperazine, and promethazine, are dopamine antagonists commonly used in the tre... . Dolasetron, granisetron, and ondansetron have not been consistently linked to any fetal malformations, although experience wit... Neurologic Agents Anticonvulsants Antipsychotics Migraine Medications Ergot Alkaloids Triptans Respiratory Agents Antihistamines Asthma Medications Corticosteroids Decongestants References 176 - Labor and Delivery Foundations Limitations of the Emergency Department Epidemiology of Emergency Delivery Patient Transfer Considerations Normal Delivery Initial Presentation Distinguishing False From True Labor Bloody Show Stages of Labor First Stage of Labor Second Stage of Labor . During labor and delivery, the identification of fetal distress and appropriate intervention can reduce fetal morbidity and mo... . Electronic fetal monitoring uses tracings of the fetal heart rate and uterine activity. Documentation of organized cyclic uter... . This is the average fetal heart rate during a 10-minute period (in the absence of a uterine contraction) and is the most impo... . This can be instantaneous (beat to beat) or long term (intervals ≥ 1 minute). Both types of variability are indicators of feta... . Decelerations in fetal heart rate are more complicated and should be interpreted according to the clinical scenario. There are... . Finally, the emergency clinician should be aware of the significance of sinusoidal tracings. Tracings of this type have low ba... . In the third trimester or during labor, ultrasonography can provide crucial information pertaining to impending delivery, suc... . As stage 2 of labor progresses, preparation for delivery should be under way. A radiant warmer should be available and heated.... . With a controlled delivery, routine performance of an episiotomy is not recommended. It should be performed only for specific ... Third Stage of Labor Fourth Stage of Labor Premature Labor Clinical Features Diagnostic Testing Management Premature Rupture of Membranes Clinical Features Diagnostic Testing Management Chorioamnionitis Vertical Transmission of Human Immunodeficiency Virus Complicated Delivery Foundations Dystocia and Malpresentation Breech Delivery Diagnostic Testing Management Shoulder Dystocia Diagnostic Testing Management Face, Brow, and Compound Presentations Multiple Gestations Diagnostic Testing Management Umbilical Cord-Related Emergencies Umbilical Cord Prolapse Clinical Features Diagnostic Testing Management Cord Entanglement Postpartum Hemorrhage Clinical Features Differential Diagnosis and Management . Accounting for 75% to 90% of cases, the most common cause of serious immediate postpartum hemorrhage is laxity of the uterus a... . Maternal birth trauma is the second most common cause of postpartum hemorrhage, accounting for up to 20% of cases. Associated ... . Approximately 10% of postpartum hemorrhage cases are due to retained placental tissue. Normally, the plane of cleavage between... . All women with postpartum hemorrhage should receive tranexamic acid (1 g IV) and should also be evaluated for disseminated int... . In the presence of ongoing hemorrhage and retained products of conception, attempts to remove the placenta manually are indica... . Pelvic bleeding postpartum can be difficult to control. Hysterectomy as a solution results in infertility and brings with it a... . When uterine bleeding is severe and uncontrolled, and embolization or hysterectomy are not available, uterine packing may be u... . Although they are commonly applied on delivery of the placenta, uterotonic agents also have special application in the case of... . Rarely, hemorrhage continues, despite the interventions outlined. In the case of life-threatening obstetric bleeding, an emer... Uterine Inversion Foundations Clinical Features Management Uterine Rupture Foundations Clinical Features Diagnostic Testing Management Amniotic Fluid Embolism Postpartum Venous Thromboembolism Postpartum Endometritis Postpartum Problems Peripartum Cardiomyopathy Postpartum Depression Clinical Features Management references 177 - Trauma in Pregnancy Anatomic Changes in Pregnancy Physiologic Changes Cardiovascular Pulmonary Gastrointestinal Specific Disorders Blunt Trauma Interpersonal Violence Falls Penetrating Trauma Fetal Injury Placental Injury Uterine Injury Diagnostic Testing Changes in Laboratory Values with Pregnancy Laboratory Kleihauer-Betke Test and Fetomaternal Hemorrhage Radiography Ultrasonography Computed Tomography and Magnetic Resonance Imaging Scans Special Procedures Diagnostic Peritoneal Lavage Management Maternal Resuscitation Primary Survey . The general principles of airway management are discussed in Chapter 1. Oxygen therapy should be instituted early in the traum... . Intravenous access with two large-bore catheters above the diaphragm is preferred. Maternal blood pressure and heart rate are... Secondary Survey . Fetal evaluation in the secondary survey focuses on the fetal heart rate and detection of fetal movement. When the presence of... Mother Stable, Fetus Stable Mother Stable, Fetus Unstable Mother Unstable, Fetus Unstable Defibrillation Resuscitative Hysterotomy Disposition References 178 - Care of the Geriatric Patient Foundations Specific Issues and Disorders Comprehensive Geriatric Assessment Cognitive Deficits: Delirium and Dementia Delirium Dementia Functional Decline, Vulnerability, and Frailty Frailty Goals of Care, Transitions of Care, and Palliative Care Transitions in Care Goals of Care and Palliative Care Nonspecific Complaints and Atypical Presentations Acute Coronary Syndrome Syncope Abdominal Pain Infections References 179 - Geriatric Trauma Foundations Background and Importance SPECIFIC ISSUES Age as a Trauma Triage Criterion Mechanisms of Injury 179 Comorbidities Medications ATLS Assessment Airway Breathing Circulation Disability Exposure Secondary Assessment Laboratory Testing Common Injuries in Older Adults Traumatic Brain Injury (TBI) Vertebral Fractures and Spinal Cord Injuries Thoracic Trauma Fragility Fractures References 180 - Geriatric Drug Therapy Foundations Pharmacokinetics 180 Pharmacodynamics Specific Disorders Polypharmacy and Drug Interactions Potentially Inappropriate Medications Beers Criteria STOPP and START Criteria Anticoagulation and Bleeding Neurologic Conditions Analgesia Clinical Pharmacy Services References 181 - Geriatric Abuse and Neglect Background Epidemiology and Scope of the Problem Clinical Features Observation and Medical History Physical Examination Diagnostic Testing Diagnostic Imaging Screening Management Emergency Medical Services Trauma-Informed Care Documentation Reporting Collaboration with the Community Resources Specific Issues Elder Mistreatment in Institutions Self-Neglect References 182 - The Immunocompromised Patient Foundations Physiology Immunity and Immune Deficiency Non–Microbe-Specific Immunity . Physical barriers, the first line of defense against microorganisms, consist of intact skin, mucosa, cilia, biofilm, gastric a... . The initial inflammatory response to microbial invasion promotes phagocytosis and microbial killing while activating the immun... . The reticuloendothelial system, composed of tissue macrophages and their blood-borne counterparts, monocytes, removes particu... Adaptive (Microbe-Specific) Immunity . Each B cell produces a single microbe-specific antibody type. Stimulation by an antigen (or microbe) causes proliferation of ... . Immunoglobulin M (IgM) is the first immunoglobulin to appear in response to a new antigen. Although it has less affinity at bi... . The complement cascade, a complex interaction of 30 proteins, is another crucial component of humoral response. Complement is ... . Cell-mediated immunity (CMI) includes immune responses mediated by T lymphocytes, natural killer (NK) cells, and mononuclear ... . Granulocytic phagocytes are the cellular effectors of microbe killing, engulfing them and enzymatically lysing their cell memb... Specific Disorders Solid Organ Transplants Cancer Neutropenia Background Febrile Neutropenia Evaluation Pitfalls Evaluation and Management . The Infectious Disease Society of America and the American Society of Clinical Oncology recommend antibiotic therapy within 60... Risk Assessment and Disposition Children With Cancer and Febrile Neutropenia Non-Neutropenic Conditions in the Cancer Patient The Solid Organ Cancer Patient Without Neutropenia Impaired Cell-Mediated Immunity . L. monocytogenes is one of the more common bacterial organisms infecting cancer patients with impaired CMI. Listeria infection... . Tuberculosis and other mycobacterial diseases may produce severe disease in those with defective CMI and be manifested as feve... . Infections with Cryptococcus neoformans and Cryptococcus gattii occur in patients with Hodgkin and non-Hodgkin lymphoma, chro... . Reactivation of central nervous system infection with the protozoan T. gondii occurs most often in patients with hematologic c... . The most common viruses producing serious infections in cancer patients with defective CMI are varicella-zoster, herpes simpl... Humoral Immune (B-Cell) Defects Disruption of Natural Barriers Opportunistic Infections Mimicking Neoplasm Diabetes Alcohol Use Disorder and Cirrhosis Renal Failure Splenectomy, Hyposplenia, and Functional Asplenia Immunosuppressive Therapy Corticosteroids Other Immunosuppressive Medications References 183 - The Solid Organ Transplant Patient Introduction Pathophysiology Anatomy Infection . Infections within the first month of transplantation often relate to postoperative intensive care and surgical site complicati... . Infections occurring within the first year of transplantation are generally divided into two categories: reactivation of laten... Rejection . Desensitization regimens decrease circulating antibodies likely to react with donor antigens in patients sensitized to incompa... . Induction immunosuppression is employed in the pre- or peri-transplantation period. Antithymocyte globulin (ATG) and alemtuz... Maintenance Immunosuppression . The calcineurin inhibitors tacrolimus and cyclosporine have greatly improved patient- and allograft-related outcomes. Howeve... . Sirolimus and everolimus are two drugs in the mammalian target of rapamycin (mTOR) class. mTOR is key in the pathway for T cel... . Azathioprine is an antimetabolite derivative of 6-mercaptopurine and inhibits both DNA and ribonucleic acid synthesis to supp... . Corticosteroids have a wide range of effects on the immune system. Every effort is made to minimize corticosteroid use to prev... . Belatacept is a fusion protein that blocks T cell co-stimulation at CD28 and is used primarily in kidney transplantation to a... Organ-Specific Considerations Heart Transplantation Anatomic Considerations Infection Rejection Drug Toxicity Kidney Transplantation Anatomic Considerations Infection Rejection Drug Toxicity Liver Transplantation Anatomic Considerations Infection Rejection Drug Toxicity Lung Transplantation Anatomic Considerations Infection Rejection Drug Toxicity Pancreas Transplantation Intestinal and Multivisceral Transplantation (IMVT) Vascularized Composite Allografts Other Considerations Post-Transplantation Malignancy Post-Transplantation Lymphoproliferative Disorder Viral Hepatitis in Solid Organ Transplantation Trauma Eligible Organ Donors Pregnancy and Solid Organ Transplantation Psychological Aspects Disposition Acknowledgements References 184 - The Morbidly Obese Patient Foundations Pathophysiology Changes to Respiratory Mechanics Obstructive Sleep Apnea and Obesity Hypoventilation Syndrome Changes in Pharmacokinetics Antibiotics Sedatives and Induction Agents Neuromuscular Blocking Agents Anticoagulation Trauma Considerations Bariatric Surgery Overview Laparoscopic Gastric Band Sleeve Gastrectomy Roux-en-Y Gastric Bypass Procedural Difficulties Lumbar Puncture Venous Access Cardiopulmonary Resuscitation Endotracheal Intubation Ventilator Management Challenges with Hospital Equipment Imaging Challenges References 185 - The Combative and Difficult Patient* Foundations Clinical Presentation Patient Characteristics Initial Patient Evaluation Management Verbal Management Techniques Physical Restraints Chemical Restraints . Benzodiazepines, particularly lorazepam (Ativan) and midazolam (Versed), are often used in the ED for rapid tranquilization of... . Antipsychotic medications play a prominent role in the chemical restraint of the violent ED patient. These medications include... . Benzodiazepines and typical antipsychotics are commonly used in combination for chemical restraint. In a 2016 meta-analysis o... . Ketamine is a dissociative anesthetic with a good safety profile used to manage the violent and acutely agitated patient in th... Post-Restraint Medical Evaluation Disposition and Medical Clearance Assault and Hostage Situations The Difficult Patient Foundations Specific Disorders Attention-Seeking Patients Demanding Patients Repeat Visitors Self-Destructive Patients References 186 - Multiculturalism, Diversity, and Care Delivery Background and Importance Rationale For Cultural Competence Changing Demographics Tests and Treatments Health Outcomes Failure of Trust Specific Issues Communication and Use of Interpreters Disability and Accommodations Overview The Hearing Impaired The Homeless Prisoners The Undocumented Cultural Competence Appreciation of Different Beliefs, Values, and Experiences Recommendations References 187 - Human Trafficking Background and Importance Epidemiology Trafficking Typologies Global and US Prevalence Demographics of Trafficked Persons Recruitment and Control Tactics Impact On Health Substance Use Mental Illness Pregnancy Specific Issues Recognition and Assessment Indicators and Red Flags Trafficking Inquiry Use of Professional Interpreters Evaluation and Treatment Trauma-Informed Approach to Care Multidisciplinary Response Disposition Admission versus Discharge Safety Planning Resources Special Considerations Mandatory Reporting Medical Record Documentation Diagnostic Codification Law Enforcement Considerations Barriers to Identification and Care References 188 - Sexual Minority Populations (LGBTQ) Background and Importance Terminology and Concepts Historical Context Identity Specific Issues Factors Affecting Equitable Care Legal Barriers Sexual Minority Parental Barriers Barriers to Health Care Access Health Care Experience Provider Education Health Disparities Transgender Health Medical Gender Affirming Therapy and Complications . For the transgender female, medical gender affirmation therapy commonly includes hormone supplementation with androgen blockin... . The most common gender affirming medical treatment utilized by transgender men is testosterone. It can be administered IM, sub... Surgical Gender Affirming Therapy and Complications . Gender affirming surgeries for transgender women included genital procedures such as orchiectomy, vaginoplasty involving the c... . Mastectomy is one of the most commonly requested surgery by transgender men. They experience the same rate and type of complic... Physical Examination Special Populations Youth Elders People of Color References 189 - Social Determinants Foundations Specific Issues Patient and Provider Factors A large number of patient and provider factors affect the care of patients (Table 189.1).2a Language Health Literacy Insurance and Access to Care Employment, Income, and Financial Strain Food Insecurity Homelessness and Housing Transportation Immigration Status Education Legal Concerns Justice Involvement The Built Environment Management Overview Health Care Access and Literacy Health Care Coverage Disability and Loss of Employment Challenges with Employers Finding Employment Income Support Management of Food Insecurity Health Care Based Resources Community-Based Resources Public Programs Housing and Homelessness Transportation Challenges Immigration Status Adjustment of Status Victims of Violence and Crime Refugees and Asylees Hospital Safe Spaces Initiatives Immigration Status and Public Charge Education-Related Challenges Domestic Concerns and Social Isolation Legal Concerns Legal Assistance Patients in Police Custody Tickets and Outstanding Warrants References 190 - Community Violence Foundations Population Characteristics and Violence Specific Issues Root Causes of Community Violence Psychological and Mental Health Hospital-Based Violence Intervention Programs Boston University HVIP Model References 191 - Sexual Assault Foundations Clinical Features Differential Diagnoses Diagnostic Testing Sexually Transmitted Infections Drug-Facilitated Sexual Assault Evaluating the Victim of Attempted Strangulation Management Medical Forensic Examination General Principles of Evidence Collection Special Techniques . Colposcopy is a diagnostic procedure to illuminate, magnify, photograph, or digitally record external and internal genital str... . Toluidine blue dye (TBD) is a stain that adheres to nuclei in damaged epithelial cells and has not been shown to interfere wit... . An alternative light source (ALS) uses ultraviolet light to fluoresce biologic material. In sexual assault examinations, the A... Special Populations Older Adult Sexual Assault Male Sexual Assault Disposition Testifying in Court References 192 - Intimate Partner Violence and Abuse Foundations Background Causes and Natural History of Intimate Partner Violence Identification Screening Clinical Features Injuries and Comorbidities Questioning Injury Presentations Specific Issues Gynecologic-Related Presentations Mental Health Presentations Alcohol and Drug Use and Intimate Partner Violence Chronic Medical Conditions Pain Syndromes Human Trafficking Diagnostic Testing Management Physician-Delivered Messages Documentation Immigration Issues Referral Danger Assessment Mental Health Screening Privacy and Confidentiality Considerations Involvement of Law Enforcement Agencies Intimate Partner Violence Coding and Diagnosis Disposition References e1 - Global Emergency Medicine The Academic Practice of Global Emergency Medicine Specific Issues History of Global Emergency Medicine Global EM Organizations Areas of Focus in Global Emergency Medicine Education Systems Development (Systems Strengthening) Research National Societies Policy Humanitarian Assistance Direct Clinical Care Clinical Rotations Abroad Preparation of the Traveler Safety and Security Research Ethics in Global EM References e2 - Humanitarian Aid in Disaster and Conflict Foundations Types of Humanitarian Emergencies Natural Disasters Disease Epidemics/Pandemics Armed Conflict Specific Issues Standards in Humanitarian Response International Law Codes of Conduct Sphere Standards Priorities in Global Humanitarian Emergencies Protection Rapid Assessment Food, Water, and Shelter Health Care Transition and Exit International Actors in Humanitarian Response Response Organizations United Nations Foreign Governments Militaries Individual Responders Coordination of Humanitarian Response Ongoing Coordination The Emergency Clinician in Humanitarian Crises Preparing for Humanitarian Response Training for Humanitarian Response Choosing a Deployment Safety and Security Ethical Dilemmas Conclusion References e3 - Emergency Ultrasound For the complete chapter text, go to ExpertConsult.com. 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Foundations Specific Issues Basic Ultrasound Information Physics and Knobology Transducer Selection Focused Assessment with Sonography in Trauma Image Acquisition Pathology Special Considerations Biliary Image Acquisition Pathology Urinary Tract Ultrasound Image Acquisition Pathology Abdominal Aorta Image Acquisition Pathology Cardiac/Hemodynamic Assessment Image Acquisition Pathology Airway/Thoracic Ultrasound Image Acquisition Pathology Ultrasound in Early Pregnancy Image Acquisition Pathology Deep Venous Thrombosis Image Acquisition Pathology Ocular Ultrasound Image Acquisition Pathology Soft Tissue Ultrasound Image Acquisition Pathology Musculoskeletal Ultrasound Image Acquisition Pathology Bowel Ultrasound Pediatric Emergency Ultrasound Ultrasound for Procedural Guidance Vascular Access Procedures Drainage Procedures Localization Procedures References e4 - The Geriatric Emergency Department Principles Background/Foundations Specific Disorders/Issues Geriatric Emergency Department Guidelines Staffing and Administration Equipment and Supplies Education Policies, Procedures, and Protocols Follow-Up and Transition of Care Quality Improvement Measures Conclusion References e5 - End of Life Foundations Palliative Care Overview Palliative Care in the Emergency Department Hospice Care Overview Hospice and the Emergency Department End-of-Life Trajectories and Prognostication Common Procedures and Interventions Faced at the End of Life Intubation and Mechanical Ventilation Cardiac Arrest Advance Care Planning and Advance Directives Overview Goals-of-Care Discussions Pain Dyspnea Death in the ED Death Notification and Breaking Bad News Viewing the Body Family Presence During Resuscitation Field Death Pronouncement References e6 - Bioethics Foundations Ethics and Emergency Medicine Specific Issues Bioethics and the Law e6 Rights and Duties Values Society’s Values Patient Values and Ethical Decisions Fundamental Bioethical Principles Nonmaleficence and Autonomy Beneficence Justice Truth-Telling Confidentiality Versus Privacy Professional Values Safety: A Unique Value Organizational and Institutional Values Professional Codes Applying Bioethics Emergency Clinician/Patient Relationship Recognizing Ethical Problems Prioritizing Conflicting Principles Case Example: Conflicting Bioethical Principles Professional Value Conflicts Rapid Ethical Decision-Making Model Advance Directives Consent Decision-Making Capacity Surrogates Family Surrogate Lists Bioethics Committees and Consultants Emergency Clinicians Courts Resuscitation Ethics Futility Withholding Versus Withdrawal of Treatments Palliative Care Notifying Survivors Viewing Resuscitations Postmortem Teaching Resuscitation Research Public Policy And Bioethics Restricted Access to Emergency Medical Care Morality of Triage Decisions Physician Response to Risky Situations References Audiovisual Recordings and Social Media Use A Global Perspective e7 - Emergency Medical Treatment and Labor Act and Medicolegal Issues Medical Screening Examination Emergency Medical Condition National Emergencies or Disasters Sexual Assault Cases Police-Requested Blood Alcohol Tests Policies, Procedures, and Practice Guidelines Central Log Medical Record Stabilization Requirements Disposition Issues Under Emergency Medical Treatment and Labor Act Admission “Discharge” or “Transfer” to Home Discharge or Transfer from the Emergency Department to an On-Call Physician’s Office Follow-Up Care After Discharge from the ED Transfers to Other Acute Care Hospitals Duty to Accept Appropriate Transfers from Other Hospitals Duty to Report Transfer Violations Consent For Medical Care Informed Consent Federal Versus State Laws Emergency Clinician Role in the Consent Process Implied Consent in Emergency Situations Minors Minors Accompanied by a Parent or Legal Guardian Unaccompanied Minors Incompetent or Incapacitated Adults Other Special Populations of Patients Prisoners Alcohol-Intoxicated Patients Patients Given Pain Medications Refusal Of Medical Care Informed Refusal Determining Competence Ensuring an Informed Decision Involving Others Documenting Appropriately Federal Rules Leaving Without Being Seen Leaving Against Medical Advice Parent or Guardian Who Refuses Care or Blood Transfusions for a Minor Jehovah’s Witnesses Adult Blood Transfusions Competent Adult Unconscious or Medically Incompetent Adult Reporting Requirements References e8 - Quality Improvement and Patient Safety Background Work Systems Resilience Sources of Failure in Emergency Care Communication and Interruptions Workspace Design Crowding Information Gaps Performance-Shaping Factors Violation-Producing Factors Teamwork Efficiency/Thoroughness Trade-Off Authority Gradients Cognitive Processes Fatigue and Shift Work Problem Areas in Emergency Care Triage Technical Procedures Laboratory Tests Radiology Studies Transitions in Patient Care Orphaned Patients Medications Summary References e9 - Patient Experience in the Emergency Department Foundations Specific Issues Challenges and Opportunities Focusing on Communication Wait Times and Expectation Setting Discharge Instructions Summary References e10 - Wellness, Stress, and the Impaired Physician Foundations Wellness Strategies Individual Health Care Organizations External Environment References e11 - Forensic Emergency Medicine Forensic Evaluation of Handgun Injuries . Handguns are the most common firearm available. There are four categories of handguns: (1) the single-shot weapon (usually a ... . The cartridge, or round, is composed of the primer, cartridge case, powder, and bullet (Fig. e11.1). The bullet is the project... Forensic Aspects of Rifles Forensic Aspects of Shotguns Forensic Aspects of Air Guns/Rifles Epidemiology Clinical Features Errors of Interpretation and Terminology Handgun Entrance Wounds . There are three subcategories of contact wounds: (1) tight contact, in which the muzzle is pushed hard against the skin; (2) l... . Close range is the maximum range at which soot is deposited on the wound or clothing. The muzzle to target distance is usually... . Tattooing, or stippling, is pathognomonic for an intermediate-range gunshot wound. Tattooing appears as punctate abrasions an... . The distant or long-range wound is inflicted from far enough away that only the bullet makes contact with the skin. There is ... . Atypical entrance wounds occur when a bullet encounters an intermediate object, such as a window, wall, or door, before striki... Handgun Exit Wounds . A shored exit wound is a wound that has an associated false abrasion collar. If the skin is pressed against or supported by a ... Centerfire Rifle Wounds Shotgun Wounds Clinical Features of Firearm Injuries Diagnostic Testing Differential Diagnosis Management and Disposition Head and Neck Injuries Thoracic Injuries Abdominal Injuries Extremity Injuries Soft Tissue Injuries Evidence Conclusions Forensic Aspects of Physical Assault Perspective Blunt Force Pattern Injuries Pattern Contusions Pattern Abrasions and Lacerations Sharp Force Pattern Injuries Thermal Pattern Injuries Chemical Injuries Forensic Aspects of Motor Vehicle Trauma Perspective Motor Vehicle Collisions Motorcycle Collisions Evaluation of Motor Vehicle Collisions Pattern Injuries Trace Evidence Evaluation of Pedestrian Collisions Pattern Injuries Interfacing with the Law Law Enforcement Exemptions to the Health Insurance Portability and Accountability Act Mandatory Reporting Subpoenas and Court Depositions References Forced Blood Draws e12 - Emergency Medical Services: Overview and Ground Transport Development of Emergency Medical Services Specific Issues Emergency Medical Service Systems Private and Public Agencies Basic Life Support and Advanced Life Support Service Single-Tiered, Multitiered, and First Responder Systems Levels of Provider and Scope of Practice Emergency Medical Responder Emergency Medical Technician Advanced Emergency Medical Technician Paramedic Material Resources Medications Equipment Ambulances Communications Access Emergency Medical Dispatch Systems Status Management and Flexible Deployment Field Communications Oversight Federal State Local Medical Director Indirect Medical Oversight Direct Medical Oversight Airway Support and Respiratory Emergencies Interventions Medications Cardiovascular Emergencies Interventions Medications Traumatic Emergencies Interventions Interfacility And Specialized Transports Acknowledgments References e13 - Air Medical Transport Specific Issues in Air Medical Transport Administrative Structure of Air Transport Systems Types of Transports Air Medical Aircraft Helicopters (Rotor-Wing Aircraft) Airplanes (Fixed-Wing Aircraft) Air Medical Flight Crew Medical Direction Safety Landing Zones Specific Disorders Trauma Burn Victims Cardiac Disorders Stroke High-Risk Obstetrics Patients Neonates and Children References Future of Air Medical Transport e14 - Disaster Preparedness Surge Capacity Definitions Classic Terminology Hazard Vulnerability Analysis Specific Issues In Disaster Management Triage Routine Multiple-Casualty Triage Catastrophic Casualty Management Vulnerable Triage Populations Special Triage Categories Care of Populations with Functional or Access Needs Out-of-Hospital Response Emergency Medical Services System Protocols Incident Management System Organization of the Out-of-Hospital Disaster Scene Planning and Hospital Response Comprehensive Emergency Management Hospital Disaster Response Plan . In a large-scale disaster, each individual hospital may need to remain self-sufficient for 48 to 72 hours or longer. Disaste... Basic Components of a Hospital Comprehensive Disaster Response Planning Process . The interdepartmental planning group (frequently referred to as the disaster or emergency preparedness committee) is composed ... . A full inventory of the hospital’s resources is necessary, including equipment, space, and personnel. It is also necessary to ... . The HICS implements an organized approach to disaster management by establishing lines of authority and decision responsibilit... . The media can be an important source of information but can also significantly disrupt the hospital’s disaster response. Arran... . Communication systems are probably the most important but also most vulnerable component of a disaster plan. Redundant systems... . The disaster plan should include a roster of all critical positions with relevant personnel and establish a reliable method fo... . A systematic approach to patient management is necessary to maximize resources. This includes protocols for decontamination, t... . On rare occasions, the hospital structure or critical infrastructure will be damaged, forcing facility evacuation. After hospi... . Disaster exercises are one of the more effective ways of familiarizing hospital staff with their responsibilities. All hospita... Toxic Disasters (Hazardous Material) Disaster Stress Management Personal Preparedness Disaster Management and Response Organizations within the United States Government Department of Homeland Security Urban Search and Rescue (ESF #9 of the National Response Framework) Department of Health and Human Services National Disaster Medical System Centers for Disease Control and Prevention Department of Veterans Affairs Department of Defense Future Directions References e15 - Weapons of Mass Destruction Specific Disorders Nuclear and Radiologic Devices Foundations Clinical Features Management Biologic Weapons Foundations Clinical Features Management Anthrax . Bacillus anthracis, a gram-positive, spore-forming bacterium, is the causative agent of anthrax (“woolsorter’s disease”). Th... . After phagocytosis by macrophages, the spores germinate and are transported to the tracheobronchial lymph nodes, where the bac... . Traditional treatment of anthrax infection has been with penicillin. However, weapons-grade anthrax is probably resistant to ... Plague . Plague has been a human pathogen since antiquity. Many regions of the world, including Asia and India, are witnessing the thir... . Primary pneumonic plague results when bacilli are inhaled into the lungs. The mortality rate approaches 100% if it is not trea... . The preliminary diagnosis of plague is clinical. Few diseases other than plague cause fulminant gram-negative pneumonia assoc... . Antibiotic treatment is essentially identical for all three types of plague (Box e15.6). The same caveats for the use of fluor... Smallpox . Smallpox was eradicated in 1980. The only known repositories of the variola virus, the etiologic agent of smallpox, are in the... . The disease manifests clinically in several forms. Variola major and variola minor represent 90% of the cases. Variola major i... . As with anthrax and plague, the initial diagnosis of smallpox is clinical. Other illnesses resembling smallpox include chicken... . For confirmation of the diagnosis, vesicular fluid or scabs are sent for electron microscopic examination or tissue culture. P... . No proven therapy exists for humans infected with smallpox who become symptomatic. However, antiviral agents such as tecovirim... Chemical Weapons Nerve Agents (Sarin, Tabun, Soman, and VX) . Nerve agents are organophosphates. They inhibit the enzyme acetylcholinesterase, blocking the degradation of acetylcholine at ... . Symptoms are receptor dependent. Stimulation of muscarinic receptors produces miosis, salivation, rhinorrhea, lacrimation, bro... . Decontamination of victims exposed to sarin vapor requires removal of clothing. People contaminated with VX or liquid sarin sh... Vesicants (Mustard) . Vesicants (blistering agents) are chemical warfare agents that induce blister formation on contact with skin. Terrorists could... . The exact mechanism is unknown, but the agent damages DNA, causing eventual cell death. These effects are similar to radiation... . Single- and three-color detector papers exist for individual use. Treatment is supportive and includes decontamination (to p... Cyanides (Blood Agents) . Cyanide molecules, most typically hydrogen cyanide or cyanogen chloride, bind to cytochromes within mitochondria and inhibit c... . Low-dose exposures result in tachypnea, headache, dizziness, vomiting, and anxiety. Symptoms subside when the patient is remo... . Victims should be removed from the area, have their clothing discarded, and receive oxygen. If no improvement occurs, the cyan... Pulmonary Intoxicants (Phosgene and Chlorine) . Pulmonary or choking agents cause an inflammatory reaction when they come into direct contact with the eyes and upper airway. ... . Exposure to pulmonary intoxicants results in a latent period between 20 minutes and 24 hours, dependent on the chemical, amoun... . Clothing should be removed to prevent secondary exposure. Strict activity limitation, including litter evacuation followed by ... Blast Injuries from Conventional Explosives Foundations Clinical Features Management References . Primary blast injury produces barotrauma, with air-containing organs such as auditory, pulmonary, and gastrointestinal being ... . Blast lung injury is a major cause of morbidity and mortality both at the scene and at the hospital among initial survivors. S... . Secondary blast injury is the most common cause of morbidity and mortality following a blast event. These injuries are caused ... . Tertiary injuries result from individuals being thrown by the blast wind. The most common types of tertiary blast injuries are... . Quaternary blast injuries comprise all explosion-related injuries, illnesses, or diseases not due to primary, secondary, or t... e16 - Tactical Emergency Medical Support and Urban Search and Rescue Principles Background Organizational Principles and Objectives Special Issues Tactical Emergency Medical Support Providers and Scopes of Practice Casualty Care Care Under Fire Tactical Field Care Combat Casualty Evacuation Care Committee for Tactical Emergency Casualty Care . To meet the specific operational scenarios and terminology used in the civilian sector, the first phase of care under TECC is ... . Indirect threat care can be initiated once the casualty is in a relatively safe area, with proper cover and less chance of res... . The final phase of care under TECC is called evacuation care, when the casualty is moved to a definitive treatment facility. M... Tactical Team Health Active Shooter Incidents Future Directions Urban Search And Rescue Medical Team Operations in Urban Search and Rescue Medical Team Tasks Predeployment Deployment Confined Space Rescue Specific Medical Challenges Crush Injury and Crush Syndrome Environmental and Hazardous Materials Exposures References
