Two Collapsed Labourers in a Cotton Field: Pesticide or Heat?
At 2:40 p.m. on a May afternoon in Guntur district the sub-inspector is called to a cotton field. A 38-year-old labourer lies unconscious between the rows, his shirt soaked with a liquid that smells of kerosene, pupils pinpoint, saliva running from his mouth, pulse 48 per minute, breathing shallow and noisy, skin cool and clammy. About 40 metres away a second labourer is confused and unsteady, with a temperature of 41.2 °C, hot dry skin and no sweating; he had been drinking water from a pot until an hour earlier. The maximum temperature recorded that afternoon was 44 °C. Three empty pesticide sachets with a monocrotophos label lie near the first man, and a knapsack sprayer is still half full with its nozzle leaking. Twenty other labourers are standing around, and two of them are trying to pour water into the unconscious man's mouth.
1. State the most probable diagnosis for each man and name the single observation that most strongly supports each diagnosis.
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First man - organophosphate (monocrotophos) poisoning. The decisive cluster is pinpoint pupils with profuse salivation and a pulse of 48. These are muscarinic effects of acetylcholine accumulating because the pesticide has inhibited cholinesterase. The kerosene smell, the leaking sprayer and the labelled sachets supply the source. Most decisive single sign: pinpoint pupils - heat stroke does not constrict the pupils.
Second man - heat stroke (classic, non-exertional). Core temperature 41.2 °C with hot dry skin and confusion, in an ambient 44 °C, fits failure of thermoregulation. Most decisive single sign: hot dry skin (absence of sweating) together with the temperature above 40 °C.
Why the first man's skin is a trap: his skin is cool and clammy, not hot. A candidate who reasons "it was 44 °C, so both men have heat stroke" is ignoring that cholinergic excess produces sweating and bradycardia, which lowers skin temperature. The two men do not have the same condition and must not be managed identically.
2. List the immediate first-aid and scene measures in the correct order, and explain the reasoning behind the measures that protect the rescuers.
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Order of action
- Stop the bystanders from pouring water into the unconscious man's mouth. An unconscious person cannot swallow; the fluid will be aspirated into the lungs.
- Put on gloves (and a mask if available) before touching the first man. His clothes are soaked in concentrate.
- Move him to shade and cut off the contaminated clothing - do not pull it over the head - and wash the skin and hair with soap and plenty of water. Decontamination must precede transport, otherwise the chemical keeps being absorbed and the ambulance crew is exposed.
- Give oxygen if the kit is available; keep him on his side; clear the airway. Do not use mouth-to-mouth. Use a bag-valve-mask. The rescuer's lips would contact pesticide on the victim's face, and vomit or saliva may carry the poison; the victim may also vomit kerosene-based solvent, which is aspirated easily.
- For the second man: shade, remove clothing, wet the skin and fan him, place ice packs at the neck, armpits and groin, and cool until about 38–39 °C. Do not force oral fluids on a confused patient.
- Scene: cordon the sprayed rows, note wind direction, stop the other labourers from re-entering, allow no smoking or eating nearby, seize the sprayer, the sachets and the purchase bill with batch numbers for the FSL, and record times and the dry-bulb temperature.
Why this matters: the constable's job is to keep the victim and the rescuers alive and the evidence intact; atropine is a hospital decision, not a police one.
3. One constable argues: "Heat and pesticide both cause unconsciousness, so just rush both men to hospital and sort it out there." Evaluate this reasoning.
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The argument is half right and dangerous in practice.
Where it is right: both men are emergencies and both need hospital care; the constable is not the diagnosing authority.
Where it fails:
- Time-critical difference. Untreated heat stroke can kill within minutes to an hour, and the treatment - rapid cooling - can be started in the field with water, shade and a fan. Delay in cooling is the main avoidable cause of death. Sending the second man on a hot 30-minute ride without cooling is worse than cooling him first for ten minutes.
- Contamination risk in transit. An un-decontaminated pesticide victim poisons the vehicle, the driver and the hospital staff. Decontamination takes minutes and must happen before loading.
- Wrong first aid is harmful. Water poured into the mouth of the unconscious man causes aspiration; mouth-to-mouth exposes the rescuer to the chemical.
- Evidence loss. If the sprayer and sachets are abandoned, the hospital cannot confirm the compound and the FSL case collapses. The batch number and bill are needed to trace the dealer.
Correct judgement: treat the scene as two different problems - cool the heat-stroke patient immediately, decontaminate the pesticide patient immediately, then transport both, with the constable's statement recording what was done and when.