This chapter describes the case of a 56-year-old male brought in by EMS after cardiac arrest. The patient had a return of spontaneous circulation after pulseless ventricular tachycardia and was intubated and transported to the ED. The primary survey reveals a patent airway, no spontaneous breaths, and palpable radial and carotid pulses. The secondary survey shows an unresponsive patient with cool and pale skin. The diagnosis is pulseless ventricular tachycardia. The chapter highlights the importance of early identification, high-quality CPR, and defibrillation as mainstays of treatment for nonperfusing rhythms. Treatment options include targeted temperature management, antiarrhythmic drugs, and consultation with cardiology. The chapter also provides pearls for managing pulseless ventricular tachycardia, including the use of hypothermia and sedation to prevent shivering.

Acute sudden-onset vision loss requires a broad differential diagnosis in the emergency department. At least a couple of true emergency conditions, including ischemic stroke, must be included. Central retina artery occlusion (CRAO) diagnosis is a real emergency condition and early management could change the patient’s prognosis. The patients with CRAO present with acute, sudden-onset, painless vision loss. Cherry red spot on the fundoscopic exam is a classic finding. Treatment includes ocular massage, breathing into a paper bag, and medications to decrease intraocular pressure. An emergent ophthalmology consultation is also required.

This case describes a patient who comes in with cough and shortness of breath. The course of inhalational anthrax can progress from initial nonspecific viral symptoms to severe respiratory distress, hypotension, hypoxia, tachypnea, cyanosis, and hemorrhage within days. Pathognomonic imaging findings include mediastinal widening due to hemorrhagic mediastinitis, pleural effusion, and mediastinal lymphadenopathy.

This chapter describes the case of a 60-year-old female with shortness of breath and neck swelling. The patient has a known history of small cell lung cancer and is currently undergoing chemotherapy. The primary survey reveals a patent airway, no apparent respiratory distress, and warm, flushed skin with equal peripheral pulses. The secondary survey shows distended superficial veins of the neck and upper chest, but clear lungs and normal abdomen. The diagnosis is superior vena cava syndrome, which is the obstruction of blood flow through the superior vena cava. The chapter highlights the importance of careful and thorough work-up of potential etiology in all cases. Treatment options include elevation of the head of the bed, diuretics, steroids, percutaneous transluminal stent placement, or bypass surgery.

A 35-year-old male with HIV presents with fever, fatigue, malaise, and a painful red rash that has spread to his abdomen and arms. He also has ulcers in his mouth and burning with urination. The primary survey reveals no respiratory distress, no cyanosis, and good peripheral pulses. The secondary survey shows purpuric macules and plaques over the neck and chest, vesicles and bullae over the extensor surfaces of the arms, and small oral erosions to bilateral buccal mucosa. The diagnosis is Stevens–Johnson syndrome, likely triggered by the patient’s recent use of a sulfur-containing antibiotic for his abscess. Critical actions include making the diagnosis based on history and physical examination, stopping the offending agent, fluid administration, dermatology consultation, and ICU or burn unit admission. Medications are the most common trigger of Stevens–Johnson syndrome, and HIV patients taking sulfamethoxazole and trimethoprim are at greater risk. Ocular involvement is common, and recurrence may occur with repeat exposure to the etiologic agent.

This is an emergency medicine oral boards case of an acute cerebellar infarction. In this case, a 72-year-old female presents to the emergency department with a chief complaint of at least 6 hours of constant dizziness, ataxia, and incoordination. Her exam is notable for bidirectional nystagmus, left upper extremity tremor, dysmetria, and dysdiadochokinesia and a wide-based unsteady gait. She also has a positive Rhomberg test. A noncontrast head CT is negative. A subsequent MRA/MRI of the brain reveals a left vertebral artery occlusion and an acute cerebellar infarction. Early critical actions in this case include the assessment for central causes of vertigo with a thorough history and neurologic exam, establishing time of onset, obtaining IV access and hemodynamic monitoring, ordering a noncontrast head CT and MRI/MRA of the brain, and obtaining immediate neurology and neurosurgery consultations. Blood pressure management with the goal of permissive hypertension (<220/120) is important. Once an ischemic infarction has been diagnosed, antiplatelet therapy with aspirin should be initiated. Because of the unknown time of onset (certainly more than 4.5 hours) this patient is not a candidate for thrombolytic treatment.

Deep vein thrombosis (DVT) commonly presents as unilateral leg swelling and pain. Risk factors for DVT include malignancy, recent surgery, history of DVT/PE, genetic predisposition to a hypercoagulable state, hospitalization, OCP/hormone replacement, pregnancy, and prolonged immobilization. D-dimer can help rule out DVT in patients with a low suspicion for DVT. Ultrasound, specifically compression ultrasonography, is a reliable way to diagnose DVT. Failure of a vein to completely compress with compression ultrasonography is diagnostic of a thrombus. Outpatient treatment with direct oral anticoagulants such as rivaroxaban and apixaban is typical. Some patients may be treated with low-molecular-weight heparin (LMWH), or LMWH bridge to warfarin. Patients with a DVT should also be evaluated for signs or symptoms of a pulmonary embolism (PE).

Seizure can have multiple precipitating factors. A broad initial differential diagnosis is critical to rapidly identify the underlying etiology of seizure, including hypoglycemia, hypoxemia, intracranial hemorrhage or infection, electrolyte abnormalities, withdrawal, or underlying epilepsy. One specific cause of seizure is pregnancy in the third trimester, termed eclampsia. Risk factors for eclampsia include young or old age, primigravida or nulliparity, multifetal gestations, obesity, chronic hypertension, kidney disease, and diabetes. The management of eclampsia includes magnesium sulfate and blood pressure control as needed. Magnesium sulfate can be given as a 4−6 g IV bolus, followed by a continuous infusion of 2 g per hour, with monitoring for magnesium toxicity as evidenced by loss of deep tendon reflexes, hypotension, or respiratory depression. Magnesium toxicity can be treated with calcium gluconate. Elevated blood pressure refractory to magnesium administration should be treated with antihypertensives, including intravenous labetalol or hydralazine, or oral nifedipine. Blood pressure targets are a systolic blood pressure of less than 160 mmHg and a diastolic blood pressure of less than 110 mmHg. Emergent obstetrics consultation is required, as delivery of the fetus is the only definitive treatment.

Anaplastic large cell lymphoma kinase-positive (ALK+) anaplastic large cell lymphoma (ALCL) is a mature T-cell neoplasm characterized by large pleomorphic cells with uniformly strong CD30 expression and ALK rearrangement with protein expression. This chapter focuses on the immunophenotypic features of ALK+ ALCL, including the common and uncommon morphologic patterns such as the small cell/lymphohistiocytic patterns. The differential diagnosis of ALK+ ALCL is also discussed, with a focus on the findings of flow cytometric immunophenotypic analysis, including peripheral T-cell lymphoma, reactive lymphohistiocytic proliferations, T-lymphoblastic leukemia/lymphoma, acute myeloid leukemia/myeloid sarcoma, and ALK+ large B-cell lymphoma. Flow cytometric immunophenotypic features that can be helpful for the differential diagnosis are discussed.

Syncope is a common presenting complaint for children and adults in the emergency department. An EKG is a part of the initial work-up for the syncope patient. Prolonged QT syndrome, an abnormal electrical conduction within the heart, can lead to syncope and sudden death from ventricular arrhythmia. Torsades de pointes is classically associated with prolonged QT syndrome, and is a life-threatening rhythm. This rhythm can be triggered by physical activity, emotional stress, swimming/diving reflex, startle reflex, and certain medications. Magnesium sulfate is the drug of choice for conversion of torsades de pointes, but unstable patients will require defibrillation.

Hypertensive emergency is an acute elevation of blood pressure (usually >180/110 mmHg) associated with end-organ injury. Hypertensive emergency can be present at lower blood pressures with hypertension-associated signs and symptoms. Treatment of hypertensive emergency includes frequent blood pressure monitoring and neurologic checks, administering IV antihypertensive medications, and evaluating for evidence of end-organ damage. The treatment goal is to reduce mean arterial pressure (MAP) by a maximum of 20−25% in the first 1−2 hours and then, if clinically stable, reduce BP to 160/100 mmHg over the next 6−12 hours. Aggressive reduction in blood pressure can lead to coronary, cerebral, or renal hypoperfusion. Pharmacologic therapy should be used to provide a predictable, titratable, and transient effect on blood pressure. If a patient presents with symptoms consistent with ischemic stroke, it is recommended to only treat BP if it exceeds 220/120 mmHg. In a patient not undergoing reperfusion therapy, treat with a goal to reduce BP by 10−15%. If the patient is a candidate for reperfusion therapy, the BP should be lowered if it is above 185/110 mmHg. Hypertensive emergency warrants medical admission with telemetry or ICU.

Snakebites can be life-threatening if the snake is venomous. Venomous snakes can be classified as elapids or crotalids, with crotalid envenomation being more common. Pit vipers, a type of crotalid, can bite and deliver venom, or without envenomation, which is called a dry bite. Crotalid venom is predominantly cytolytic and may cause edema, hemorrhage, and necrosis close to and far away from the bite. Systemic signs and symptoms may include hemolysis, thrombocytopenia, disseminated intravascular coagulopathy, vomiting, and cardiovascular and respiratory failure. If no local or systemic signs are noted, the patient can be monitored for 12 hours and released if no signs or symptoms develop. Antivenom should be provided if the patient experiences signs or symptoms of envenomation.

This chapter contains a case of pediatric fever in a 20-month-old child with fever for five days. This case goes through the typical presentation of a child with Kawasaki disease, which is an acute vasculitis of childhood. Kawaski disease is known to be the leading cause of acquired heart disease in North American children. Though the cause remains unknown, the disease is well described clinically as: fever for 5 days, conjunctival injection, oral mucosa erythema, swelling or desquamation of the palms and soles, polymorphous rash, and cervical lymphadenopathy. Lab abnormalities such as an elevated ESR, CRP, and WBC can support the diagnosis or aid in diagnosing incomplete or atypical Kawasaki. Other labs that can support this would be left shift of WBC, anemia for age, thrombocytosis, sterile pyuria, ALT elevation, and low albumin. Kawasaki disease is associated strongly with coronary artery aneurysms; however, a small percentage of patients develop dysrhythmias or myocardial infarction. Treatment of Kawasaki disease includes IVIG and aspirin.

This chapter describes the immunophenotype of adult T-cell leukemia/lymphoma (ATLL). The differential diagnosis, including mycosis fungoides/Sezary syndrome (MF/SS), T-prolymphocytic leukemia (T-PLL), anaplastic large cell lymphoma (ALCL), and normal T-regulatory cells, is discussed in detail.

This chapter covers the evaluation and management of an adolescent patient presenting to the emergency department with an aspirin overdose.

This chapter presents a case of a 34-year-old male with chest pain due to a post-viral myopericarditis. The case highlights the approach to a young patient with chest pain, and details many of the pertinent historical details and exam findings that support this diagnosis. The approach to diagnostic testing, risk stratification based on echocardiography and laboratory values, and spectrum of disease and management are described.