Methemoglobinemia revisited: an important complication after transesophageal echocardiography.

Methemoglobinemia induced by the use of benzocaine-containing topical anesthetics is a rare, but potentially lethal complication after transesophageal echocardiography (TEE). We report a patient who developed methemoglobinemia after TEE. A review of the literature was performed and the majority of cases of benzocaine-induced methemoglobinemia reported thus far have occurred in patients undergoing TEE, endotracheal intubation, esophagogastroduodenoscopy, and bronchoscopy. All of these procedures have become more frequent than before, and there is a need to reemphasize the potential problem and to reconsider the need for further use of topical anesthetics.