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Carbon monoxide poisoning — MCCQE Part 1 MCQ

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EasyPoisoning/OverdoseCarbon monoxide poisoningMCCQE Part 1

A family presents in winter with headache, nausea and dizziness after using a generator indoors. Pulse oximetry reads 99% in all members. Which of the following is the most appropriate next step?

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

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Correct answer: D — Give high-flow oxygen and measure carboxyhaemoglobin while arranging public safety measures

Carbon monoxide poisoning often has falsely normal pulse oximetry because standard oximeters cannot distinguish oxyhaemoglobin from carboxyhaemoglobin. High-flow oxygen reduces the half-life of carboxyhaemoglobin. The home environment must be addressed to prevent recurrent exposure.

Reference: Canadian emergency medicine toxicology practice; Health Canada CO safety resources