title: Benzocaine-induced methaemoglobinaemia: a life-threatening complication after a transoesophageal echocardiogram (TEE).
abstract: Acquired methaemoglobinaemia is a potentially fatal impairment in oxygen delivery if not recognised early and treated appropriately. Benzocaine used as an anaesthetic for endoscopic procedures is an uncommon but clinically important precipitant of acquired methaemoglobinaemia. We present a case of an elderly woman who developed perioral cyanosis and desaturation 20 min after a transoesophageal echocardiogram. Further evaluation led to the diagnosis of benzocaine-induced methaemoglobinaemia and timely treatment with intravenous methylene blue was initiated.
authors.affiliation: Department of Internal Medicine, Reading Health System, West Reading, Pennsylvania, USA.
authors.forename: Madan Raj
authors.initials: MR
authors.lastname: Aryal
authors.forename: Shobhit
authors.initials: S
authors.lastname: Gupta
authors.forename: Smith
authors.initials: S
authors.lastname: Giri
authors.forename: Julian Diaz
authors.initials: JD
authors.lastname: Fraga
mesh_terms: D000368:Aged; D000779:Anesthetics, Local / Q000009:adverse effects*; D001566:Benzocaine / Q000009:adverse effects*; D017548:Echocardiography, Transesophageal / Q000379:methods; D005260:Female; D006801:Humans; D008708:Methemoglobinemia / Q000139:chemically induced* / Q000188:drug therapy; D008751:Methylene Blue / Q000627:therapeutic use
chemical_list: D000779:Anesthetics, Local; D008751:Methylene Blue; D001566:Benzocaine
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