Journal: AANA Journal 76(2):99-102, 2008
Reprint: Certified Anesthesia Care, Minneapolis, Minnesota
Faculty Disclosure: Abstracted by T. Tilton, who has nothing to disclose.
A case report is made of a healthy 27-yr-old male, 63 kg, 160 cm, who fell about 3.6 m from a ladder. He was not intoxicated and did not lose consciousness. He was transported to the emergency department where computed tomography (CT) revealed a bladder rupture that was repaired during exploratory laparotomy. A nasogastric tube (NG) had been in place for 4 of 5 days of his hospitalization and he used benzocaine (Hurricane) spray orally as needed to alleviate the throat discomfort. Recovery was uneventful and he was discharged.
The patient returned a month later due to abdominal discomfort, nausea, and vomiting. Cystogram showed a leak and diffuse dilatation in the small bowel. Abdominal CT showed an obstructing lesion near the mid-jejunum and a leak in the bladder wall. He was admitted and an NG tube placed. Hurricane spray 1-2 puffs every 4-6 hours and Cepacol lozenges as needed were ordered. He was scheduled for another explora¬tory laparotomy for lysis of adhesions, bladder repair, and small bowel resection. His blood pressure was 130/98 mmHg and heart rate 100 beats/min. His skin color was "gray", with gray nailbeds, pale lips, and an oxygen saturation (SpO2) of 89% (100% nonrebreath¬ing mask raised the saturation to only 90%). Following rapid sequence induction and intubation, SpO2 was still only 91%. Arterial blood gas showed pH 7.31, PCO2 was 40 mmHg, PO2 533, bicarbonate 13 mEq/L, base excess -16 mEq/L, and a calculated oxygen saturation 100%. With these readings, the brown appearance of the blood, and an elevated methemoglo¬bin (MHb) level, methemoglobinemia was diagnosed. Methylene blue, 65 mg was administered and within 30 min, SpO2 readings were 98-99%. Surgery and recovery were uneventful.
Methemoglobinemia is a known side effect of exces¬sive benzocaine usage and is avoided by following dosage recommendations. Prompt diagnosis and treat¬ment are required. |
