Heat, Excessive
Exertional vs classic heat stroke, rapid whole-body immersion cooling, and central nervous system signs
// IMMEDIATE ACTIONS
Execute these steps in order:
- 01 CALL 911 / 112 IMMEDIATELY (HEAT STROKE EMERGENCY)
Report severe hyperthermia / heat stroke if altered mental state, confusion, or seizures are present.
- 02 AGGRESSIVE RAPID WHOLE-BODY COOLING
Immerse in cold water bath if available, or douse body with cold water and fan continuously while applying ice packs to neck, armpits, and groin.
- 03 MONITOR AIRWAY & PROHIBIT ORAL FLUIDS IF DROWSY
Place in recovery position if consciousness declines; never give fluids to a confused patient due to choking risks.
// CRITICAL MISTAKES (DO NOT)
- ✕ Do not delay aggressive cooling to wait for an ambulanceWHY: cooling must begin in the field within minutes of collapse
- ✕ Do not give fever medications (aspirin, paracetamol/acetaminophen, ibuprofen) as they damage kidneys/liver and have zero effect on environmental hyperthermia.
- ✕ Do not force water or electrolyte drinks on an uncoordinated, confused, or vomiting patient.
- ✕ Do not rely solely on ice packs on the forehead or wristsWHY: cooling surface area is far too small
“Cool first, transport second: immerse in cold water immediately, call 911/112, and never give antipyretic fever pills.”
When ambient air temperature and relative humidity rise, the human body's primary cooling mechanism—evaporative sweat cooling—breaks down. If internal metabolic heat generation exceeds environmental dissipation, core body temperature surges past 40°C (104°F).
The Cellular Destruction of Hyperthermia
At core temperatures above 40.5°C (105°F), cellular enzymes and structural proteins throughout the brain, liver, and cardiovascular system undergo thermal denaturation.
The blood-brain barrier breaks down, causing cerebral edema and neurological collapse (manifesting as agitation, bizarre behavior, seizures, and coma). Meanwhile, the intestinal mucosal barrier becomes permeable, dumping bacterial endotoxins directly into the circulation and triggering systemic inflammatory response syndrome (SIRS), disseminated intravascular coagulation (DIC), and multi-organ failure.
The "Cool First, Transport Second" Mandate
In exertional heat stroke, mortality is directly proportional to the total time spent above critical temperature thresholds. Waiting for an ambulance before beginning active cooling increases mortality drastically. Whole-body immersion in cold or iced water extracts heat at over 0.20°C per minute, rapidly returning core temperature to safe levels and halting the systemic inflammatory cascade.
112 reaches fire and emergency medical dispatch directly. 110 is police.
Additional safety instructions and adjacent hazard knowledge.