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Published on: May 12, 2019
Benzocaine-induced methemoglobinemia
Frederick Hegedus1, Kathleen Herb
1Department of Oral and Maxillofacial Surgery, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107, USA.
Abstract:
A case is reported in which a patient developed methemoglobinemia-induced cyanosis while under general anesthesia during surgery for multiple fascial space infections. The cause of methemoglobinemia was 20% benzocaine spray used for local anesthesia before intubation. Acutely developing methemoglobinemia is infrequently encountered in clinical practice. When confronted with cyanosis in the absence of cardiac or pulmonary disease, one must seriously consider the diagnosis of methemoglobinemia. The etiology of methemoglobinemia, the causative agents, the diagnosis, and the emergency treatment required are discussed.
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