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?

  1. A)Donepezil
  2. B)Sevoflurane
  3. C)BenzocaineGABARITO
  4. D)Lidocaine
  5. E)Bupivacaine

Explicação

Benzocaine is the correct answer because certain local anesthetics, especially benzocaine and prilocaine, can cause methemoglobinemia, producing low oxygen saturation with a normal PaO2 and chocolate-brown blood. Ver explicação completa e trilha adaptativa →

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