Two Men Fall Out on Parade: Heat Exhaustion or Heat Stroke?
In the last week of May a platoon of 300 constables is drilled on an open ground from 1:30 p.m.; the day's maximum is 44 °C and relative humidity is 25 per cent. After fifty minutes Constable Meena, who ate nothing since the previous evening, stops sweating, is confused, and his skin is hot and dry; his pulse is 130 a minute. Ten metres away Constable Ansari is sweating heavily, feels dizzy and nauseated, but is fully conscious and knows where he is; his pulse is 96. A head constable opens a bottle of cold water for Meena and tells two constables to carry him to a shaded tent 200 metres away. At the post there are ORS packets, a canvas stretcher, two buckets of water, and a jeep with a working air-conditioner. The nearest community health centre is nine kilometres away and the ambulance will take at least twenty minutes.
1. Differentiate the two constables' conditions and say which one is the emergency.
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Meena is the emergency: heat stroke. Ansari has heat exhaustion.
| Feature | Meena | Ansari |
|---|---|---|
| Mental state | Confused, disoriented | Conscious, oriented |
| Sweating | Absent, skin hot and dry | Profuse |
| Pulse | 130/min | 96/min |
| Meaning | Thermoregulation has failed, central nervous system is affected | Volume depletion and salt loss, thermoregulation intact |
The decisive criterion is altered mental status in a hot environment, not the temperature reading. Heat stroke is a medical emergency with a death risk that rises with every minute of delay; heat exhaustion is serious but recovers with rest, shade, fluids and salt. A note of caution for the answer: in exertional heat stroke sweating may persist, and in very dry air sweat can evaporate invisibly, so dry skin alone is not proof - but here the confusion plus hot skin plus tachycardia make heat stroke the clear working diagnosis. Meena's fasting state adds a risk factor (hypoglycaemia and poor heat tolerance).
2. Evaluate the head constable's two actions - offering water and carrying the man 200 m - and state the correct first response order.
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Both actions are well meant and both are partly wrong in sequence.
- Water by mouth is unsafe here. Meena is confused; his gag reflex cannot be trusted. Oral fluids in an altered patient risk aspiration into the lungs, which can kill faster than the heat. Oral fluids are correct only for a fully conscious, cooperative patient - i.e., for Ansari (ORS, small frequent sips), not for Meena.
- Carrying him 200 m before any cooling wastes the most valuable minutes. Cooling must begin at the spot: shade, strip to the waist, wet the body with the buckets, and fan vigorously. Evaporative cooling works extremely well in 25 % humidity - that is the one advantage this weather gives.
Correct order:
- Shout for the ambulance (108) and put the CHC on notice.
- Shade, remove clothing, wet skin, fan; ice or cold packs at neck, armpits and groin if available; immersion in the water of the buckets if feasible.
- Move him to the air-conditioned jeep only while continuing cooling, not before starting it.
- Do not give oral fluids; do not give paracetamol (it does not lower heat-stroke temperature); do not leave him unmonitored.
3. Why does the low humidity matter for the choice of cooling method, and why is Ansari's ORS justified while Meena's is not?
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Humidity and cooling. In dry air (25 % relative humidity), the evaporation of water from skin is fast, and evaporation carries away far more heat per gram than simple conduction. So wetting the skin and fanning is the single most effective field method here; it would be much weaker in humid coastal air, where ice packs and immersion would matter more. The same dry air explains a trap: sweat can evaporate so quickly that the skin feels dry even when the man is still sweating, which is why the mental state, not the skin, is the deciding sign.
ORS reasoning. Ansari has heat exhaustion: he has lost water and salt through heavy sweating, his circulation is stressed but his brain and temperature control are intact, so replacing both water and electrolytes by mouth is safe and curative. Meena has heat stroke: the priority is physical cooling and hospital care, his swallowing is unreliable, and oral fluid would not correct the core problem. If he is conscious and fully alert after cooling begins, small sips may be allowed with medical advice; until then, intravenous fluid at the hospital is the route.