Exertional heat stroke — DTM&H MCQ

Correct answer: B — Immediate rapid cooling with supportive resuscitation

The correct answer is B, immediate rapid cooling with supportive resuscitation. This man has exertional heat stroke, defined by a core temperature above 40°C with neurological impairment (confusion) following strenuous exertion in a hot, humid environment. Heat stroke is a medical emergency in which the body's thermoregulatory mechanisms fail, so the priority is to actively reduce core temperature as fast as possible, ideally by cold water immersion, alongside airway, breathing, circulation support and fluid resuscitation. Reducing core temperature below 38.9°C within the first 60 minutes is directly linked to improved survival, and delay in cooling correlates with multi-organ injury and mortality that can reach 80% if untreated. Why the other options are wrong: C. Oral paracetamol and observation: Antipyretics act on the hypothalamic set point in fever; heat stroke is a failure of heat dissipation, not a hypothalamic fever, so paracetamol has no physiological role and observation alone risks fatal delay. D. Delay cooling until transfer to hospital: Any delay in cooling directly worsens outcome since survival correlates with time to reach a safe core temperature; cooling must start immediately at the scene, not after transfer. E. High-dose antibiotics as first-line therapy: There is no evidence of infection here; the presentation is exertional hyperthermia with dry skin after exertion, not sepsis, so antibiotics are not indicated as first-line treatment. A. Fluid restriction to prevent cerebral oedema: Heat stroke causes hypovolaemia and shock from fluid losses and vasodilation, so patients need prompt intravenous fluid resuscitation, not restriction. Key point: In exertional heat stroke, survival depends on how fast core temperature is lowered, so cooling begins immediately on scene, not after arrival at hospital.

Reference: British Journal of General Practice, Management of exertional heat stroke: a practical update for primary care physicians, 2018, https://bjgp.org/content/68/668/153