Neurodegenerative Diseases USMLE Step 1 Practice Question
A 54-year-old man presents with cyanosis and dyspnea 4 hours after dental work with topical anesthesia. Vitals show HR 98 bpm, BP 132/78 mmHg, RR 22/min, SpO2 85% on room air. Arterial blood gas reveals normal PaO2 of 95 mmHg. Methemoglobin level is elevated at 18%. He denies chest pain or recent medications. Which topical anesthetic agent is most likely responsible for this presentation?
Answer choices
- ADonepezil
- BSevoflurane
- CBenzocaineCorrect answer
- DLidocaine
- EBupivacaine
- FPrilocaine
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