Toxicology USMLE Step 1 Practice Question
A 28-year-old man is rescued from a burning residential house after being trapped for approximately 20 minutes in an enclosed room. On arrival to the emergency department, he is obtunded and unable to follow commands. His vital signs include BP 85/52 mmHg, HR 118/min, RR 22/min, and temperature 37.8°C. Physical examination reveals singed nasal hairs, soot deposits around the mouth and nares, and flushed skin. Despite administration of 100% supplemental oxygen via non-rebreather mask, arterial blood gas analysis demonstrates a severe lactic acidosis with pH 7.18 and lactate 12 mEq/L. Carboxyhemoglobin level returns at 38%. The patient's girlfriend confirms he did not ingest any substances prior to the fire. Which antidote is most appropriate for this patient's condition?
Answer choices
- AN-acetylcysteine
- BAtropine
- CHydroxocobalaminCorrect answer
- DDeferasirox
- ENaloxone
- FSodium thiosulfate
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