A 26-year-old man is brought to the emergency department after collapsing 2 hours into basketball practice. Immediately prior to collapse, the patient developed a headache and dizziness. His parents report that he has a history of atypical depression, for which he takes quetiapine; he also underwent laparoscopic appendectomy 3 months ago. Temperature is 41 C (105.8 F), blood pressure is 88/48 mm Hg, pulse is 136/min, and respirations are 26/min. The patient is disoriented but protecting his airway. Mucous membranes are dry. Cardiac examination shows tachycardia with a regular rhythm. Lungs are clear bilaterally. The abdomen is soft and nontender. Muscle tone and reflexes are normal. Which of the following is the best next step in management of this patient?

Question

A 26-year-old man is brought to the emergency department after collapsing 2 hours into basketball practice.  Immediately prior to collapse, the patient developed a headache and dizziness.  His parents report that he has a history of atypical depression, for which he takes quetiapine; he also underwent laparoscopic appendectomy 3 months ago.  Temperature is 41 C (105.8 F), blood pressure is 88/48 mm Hg, pulse is 136/min, and respirations are 26/min.  The patient is disoriented but protecting his airway.  Mucous membranes are dry.  Cardiac examination shows tachycardia with a regular rhythm.  Lungs are clear bilaterally.  The abdomen is soft and nontender.  Muscle tone and reflexes are normal.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d1d4_224b_bc81_9f482044d490_MD0003_00 This patient with hyperthermia, disorientation, and hypotension that occurred during prolonged exercise has exertional heat stroke (EHS). EHS is a heat-related illness characterized by a core temperature >40 C (104 F) associated with CNS dysfunction (eg, altered mental status [AMS], seizure); these features help differentiate EHS from heat exhaustion (no CNS dysfunction, hyperthermia ≤40 C [104 F]). EHS typically occurs in otherwise healthy persons who are exercising in extreme heat or high humidity, which interferes with the body's ability to undergo evaporative cooling from sweat. Other risk factors for EHS include obesity, poor exercise tolerance, limited acclimatization to current weather conditions, and certain medications (eg, anticholinergics, antipsychotics such as quetiapine) that interfere with thermoregulatory mechanisms. Other signs and symptoms of EHS include hypotension, tachycardia, hyperventilation, flushing, and diarrhea. Diaphoresis may occur, depending on volume status. Oxidative stress and tissue hypoxia can result in rhabdomyolysis, disseminated intravascular coagulation, and end-organ dysfunction (eg, renal or hepatic failure, pulmonary edema). First-line management involves rapid cooling with ice water immersion. If an ice water bath is not available, alternative cooling methods (eg, cold water shower) should be used. Because EHS is primarily due to impaired thermoregulatory mechanisms rather than cytokine production, there is no role for antipyretic therapy (eg, acetaminophen). Morbidity and mortality are directly associated with the duration of hyperthermia; therefore, fluid resuscitation and correction of electrolyte abnormalities should be considered only after cooling has begun. (Choice B) Cyproheptadine is used to treat serotonin syndrome, which can occasionally occur with quetiapine use but is more commonly seen with serotonin-modulating medications (eg, selective serotonin reuptake inhibitors, tramadol). Although serotonin syndrome also causes hyperthermia and AMS, hyperreflexia is typical, and EHS is more likely in a patient performing prolonged exercise. (Choice C) Dantrolene is used in neuroleptic malignant syndrome (NMS), which can develop in patients taking antipsychotic agents (eg, quetiapine), and malignant hyperthermia (MH), which occurs in genetically susceptible individuals given inhalation anesthetics. Both can cause hyperthermia, tachycardia, and AMS. However, muscle rigidity is typically present. In addition, NMS symptoms generally develop over several days (not 2 hours), and MH occurs within minutes of anesthesia administration (not months later). (Choice D) High-dose ceftriaxone with vancomycin is first-line therapy for bacterial meningitis, which presents with high fever, neck stiffness, and AMS. Meningitis is unlikely in this patient who was well prior to basketball practice. (Choice E) Oral hydration and Trendelenburg positioning are appropriate for exercise-associated collapse, which occurs in conditioned athletes immediately after cessation of exercise due to a sudden decrease in cardiac preload. Although syncope can occur, prolonged AMS and severe hyperthermia are unexpected. Educational objective: Exertional heat stroke is characterized by temperature >40 C (104 F) and CNS dysfunction (eg, altered mental status, seizure). First-line treatment is rapid cooling with ice water immersion.

A 26-Year-Old Man Is Brought to the Emergency Department After