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Organophosphate poisoning — SCE Acute Medicine MCQ

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HardToxicology and OverdoseOrganophosphate poisoningSCE Acute Medicine

A farm worker exposed to an organophosphate insecticide has bronchorrhoea, wheeze, bradycardia, pinpoint pupils and fasciculations. Staff have removed contaminated clothing using protective equipment. Which antidote regimen is most appropriate?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: B — Atropine 2 mg repeated to atropinisation plus pralidoxime about 30 mg/kg

Explanation lettering: B = shown as A · C = shown as B · A = shown as C

C is correct. Oxygenation, suction and ventilatory support accompany atropine, initially about 2 mg in an adult and repeated or escalated until bronchial secretions and bronchospasm improve; pupil size is not the resuscitation endpoint. Pralidoxime about 30 mg/kg should be given early when the compound is oxime-responsive and specialist advice obtained. The other doses reverse the two antidotes, omit muscarinic treatment, or use physostigmine, which increases acetylcholinesterase inhibition. Safe decontamination protects staff from secondary exposure.

Reference: https://www.hse.gov.uk/pesticides/assets/docs/Lab-HB-Vol-2-Professional.pdf