Severe methemoglobinemia on reexposure to benzocaine.

摘要

We report a 65-year-old male who developed severe methemoglobinemia only on reexposure to benzocaine. The patient needed two awake fiberoptic intubations for emergency surgeries. On the second exposure, the patient was septic and malnourished, and he was taking acetaminophen. He developed a methemoglobin level of 55%. Possible reasons for the methoglobinemia on reexposure are discussed in this report.