Toxicology USMLE Step 1 Practice Question
A 47-year-old man is brought to the emergency department by coworkers after accidentally ingesting windshield washer fluid approximately two hours ago at an auto repair shop. He is confused and agitated, and complains that his vision has become blurred with halos around lights. His temperature is 37.2°C, blood pressure is 138/86 mmHg, heart rate is 110/min, and respiratory rate is 22/min with a deep, labored quality. Physical examination reveals papilledema and sluggish pupillary responses bilaterally. Laboratory studies show a serum pH of 7.18, bicarbonate of 12 mEq/L, serum osmolality of 340 mOsm/kg with a calculated osmolality of 295 mOsm/kg, and a serum lactate of 4.1 mmol/L. Which of the following treatments is most appropriate to block formation of the toxic metabolite responsible for his presentation?
Answer choices
- AMethylene blue
- BPyridoxine
- CFomepizoleCorrect answer
- DHydroxocobalamin
- ENaloxone
- FEthanol infusion
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