Correct!
4. Both 1 and 3
Heat-related illness is a set of conditions which range from milder forms to potentially fatal heatstroke. Heat exhaustion is the inability to continue activity because of environmental conditions, and is thought to be caused by a central mechanism that protects the body in times of overexertion (2). As a milder form of heat-related illness, heat exhaustion usually has core temperatures less than 104°F (40°C) and no central nervous system symptoms. If left untreated, heat exhaustion could lead to heatstroke.
Heatstroke can be categorized as classic or exertional. Classic heat stroke is due to exposure to environmental heat and poor heat-dissipation mechanisms, whereas exertional heatstroke is often associated with physical exercise and results when excessive production of metabolic heat overwhelms physiological heat-loss mechanisms (1). Classic heatstroke often affects the chronically-ill, elderly and prepubertal, who have poor heat-dissipation mechanisms. Exertional heatstroke occurs more frequently in the generally healthy, young and active, and can also occur with drug abuse due to increased metabolic demand. This patient had been exposed to high temperatures which was likely exacerbated in the setting of methamphetamine use, making it a mixed classic and exertional heatstroke picture.
Heatstroke has three phases: hyperthermic-neurologic, hematologic-enzymatic phase (peaking 24-48 hours post event), and late renal-hepatic phase. In severe cases, sustained brain injury to the autonomic and enteric nervous system can occur. Two days later, the patient was weaned off of pressor support but remained encephalopathic and required ventilator support. The patient’s laboratory results are shown:
What is the most likely cause of this patient’s abnormal liver enzymes? (Click on the correct answer to be directed to the fourth of six pages)