Toxicology USMLE Step 1 Practice Question
A 31-year-old woman is rescued from a house fire. She presents with BP 88/52, HR 112, RR 22, SpO2 98% on supplemental oxygen, and altered mental status. Laboratory testing reveals serum lactate 8.2 mmol/L despite adequate oxygen delivery and normal hemoglobin saturation. Arterial blood gas shows metabolic acidosis. She denies chest pain. Which antidote most directly binds cyanide to form cyanocobalamin?
Answer choices
- AFlumazenil
- BHydroxocobalaminCorrect answer
- CSodium bicarbonate
- DPralidoxime
- EDeferoxamine
- FMethylene blue
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