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Type 1 diabetes sick day — USMLE Step 3 MCQ

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HardPediatrics (Well-child / Chronic Management)Type 1 diabetes sick dayUSMLE Step 3

A 28-year-old at 18 weeks gestation is found confused in a house heated by a faulty generator. After removal from the house and 100% oxygen, her confusion resolves. Carboxyhemoglobin is 17%, ECG and troponin are normal, and fetal heart activity is present. Which management is most appropriate?

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Correct answer: E — Continue 100% oxygen and obtain urgent hyperbaric-oxygen consultation because she is pregnant

The best answer is “Continue 100% oxygen and obtain urgent hyperbaric-oxygen consultation because she is pregnant”. Pregnancy warrants aggressive treatment because fetal hemoglobin binds carbon monoxide avidly and fetal elimination is slower than maternal elimination. The maternal level may underestimate fetal exposure. Immediate 100% oxygen continues while a hyperbaric center is consulted; pulse oximetry is unreliable in carbon monoxide poisoning, and methylene blue treats methemoglobinemia. The alternatives are less suitable because they mistime the intervention, omit a necessary component, or apply treatment for a different physiologic problem; the stem's decisive findings determine the sequence.

Reference: CDC, Clinical Guidance for Carbon Monoxide Poisoning: https://www.cdc.gov/carbon-monoxide/hcp/clinical-guidance/index.html