Lee E, Boorse R, Marcinczyk M
Department of Internal Medicine, Lehigh Valley Hospital, Allentown, Pennsylvania 18105-1556, USA.
Surg Laparosc Endosc. 1996 Dec;6(6):492-3.
An 80-year-old white woman with a history of hypertension presented to the Emergency Department with bright red bleeding from the rectum. She was treated with 5 mg of midazolam and benzocaine topical anesthetic spray prior to undergoing colonoscopy and esophageal gastroduodenoscopy. Thirty minutes after endoscopy, the patient became cyanotic and dyspneic; she was suffering from methemoglobinemia, a rare complication secondary to the use of benzocaine topical anesthetic spray. After i.v. administration of methylene blue, 120 mg (2 mg/kg) in 100 cc of normal saline solution, the cyanosis and dyspnea resolved.
