Heat stroke and hyperthermia

Manage now— do this, in order

• Cooling is the treatment and it precedes the diagnostic work-up: mortality is directly proportional to the duration and magnitude of the hyperthermia. Undress the patient completely and remove them from the heat the moment the diagnosis is suspected — an inferior technique applied in the first minute beats a superior one applied in the twentieth.
• Evaporative and convective cooling is the workhorse, preferred for classic heat stroke: laterally recumbent or on hands and knees, spray the whole body with lukewarm-to-cool water (Harrison's 15°C, CMDT 20°C) and run large fans over the wet skin, keeping it continuously wet. Ice or cold water immersion (0.20–0.35°C/min) is the fastest and the method of choice for young, previously healthy exertional heat stroke. Adjuncts: wet towels/ice packs (change towels constantly, cover as much body as possible), skin and muscle massage against vasoconstriction.
• Targets: reduce the core temperature within one hour, chart it every 5 minutes, and stop active cooling at approximately 38–39°C to avoid hypothermic afterdrop — children overshoot into hypothermia quickly and must be dried immediately once cooling stops.
• Airway and oxygen: aspiration commonly occurs and endotracheal intubation is usually necessary; keep suction available, nurse laterally while unprotected. High-flow oxygen 15 L/min via reservoir mask pending blood gases. If paralysis is needed — never suxamethonium (lethal potassium rise in rhabdomyolysis, may trigger malignant hyperthermia): rocuronium 1 mg/kg IV or vecuronium 0.1 mg/kg IV, same doses in children.Doctor / NurseNot available at your setup — Endotracheal intubation kit.
• Fluid by type: repeated discrete boluses of isotonic crystalloid, preferable to alpha-agonists (vasoconstriction delays heat loss) — adult 500 mL 0.9% sodium chloride or balanced crystalloid over 15 minutes, child 20 mL/kg, reassessing each time. Classic heat stroke needs only cautious repletion (CVP often 12–14 mmHg despite dehydration; over-filling causes pulmonary oedema); exertional needs far more vigorous crystalloid.Doctor / Nurse
• Hypoglycaemia: adult 100 mL of 20% glucose or 200 mL of 10% glucose IV; child 10% glucose 2 mL/kg IV; recheck after 10 minutes.Doctor / Nurse
• Suppress shivering — it generates heat and inhibits cooling: adult midazolam 1–2 mg IV repeated cautiously and titrated, or diazepam 5 mg IV slowly; child midazolam 0.05–0.1 mg/kg IV slowly (0.3 mg/kg buccal or intranasal without IV access), or diazepam 0.5 mg/kg per rectum for seizures. Never chlorpromazine — it lowers the seizure threshold, inhibits sweating, worsens hypotension and can itself cause neuroleptic malignant syndrome.Doctor / Nurse
• Kidneys and potassium: catheterise, chart urine output hourly, titrate crystalloid to 1–2 mL/kg/h. For hyperkalaemic ECG changes give calcium gluconate 10% 10 mL IV over 5–10 minutes (child 0.5 mL/kg, maximum 20 mL), then insulin–glucose and nebulised salbutamol — treat before the laboratory potassium returns. If external cooling fails within 20–30 minutes or rigidity persists: paralyse with a nondepolarising blocker, intubate and ventilate; if hyperthermia and rigidity persist despite blockade, the mechanism is malignant hyperthermia — dantrolene 2–5 mg/kg IV.Doctor / Nurse
• Never give antipyretics — they are contraindicated: there are no pyrogens and no shifted set point in hyperthermia; salicylates further uncouple oxidative phosphorylation and worsen coagulopathy, and paracetamol further stresses the hepatocyte — the most heat-sensitive organ the patient has. Never a diuretic for the crackles of a hypovolaemic patient, and no reflex antiarrhythmics — tachyarrhythmias and ST–T changes usually resolve with cooling.