Methemoglobinemia caused by a low dose of prilocaine during general anesthesia
10.17245/jdapm.2021.21.4.357
- Author:
Makiko SHIBUYA
1
;
Takayuki HOJO
;
Yuri HASE
;
Yukifumi KIMURA
;
Toshiaki FUJISAWA
Author Information
1. Department of Dental Anesthesiology, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University, Sapporo, Japan
- Publication Type:Case Report
- From:Journal of Dental Anesthesia and Pain Medicine
2021;21(4):357-361
- CountryRepublic of Korea
- Language:English
-
Abstract:
Methemoglobinemia is a blood disorder in which an abnormal amount of methemoglobin is produced, and prilocaine is one of the drugs that can cause this disorder. The maximum recommended dose of prilocaine is 8 mg/kg. We report a case of methemoglobinemia caused by the administration of 4.2 mg/kg of prilocaine without other methemoglobinemia-inducing drugs during general anesthesia. A 17-year-old girl with hyperthyroidism and anemia was scheduled to undergo maxillary sinus floor elevation and tooth extraction. The patient’s peripheral oxygen saturation (SpO 2 ) decreased from 100% at arrival to 95% after receiving prilocaine with felypressin following induction of general anesthesia. However, the fraction of inspired oxygen was 0.6. Blood gas analysis showed that the methemoglobin level was 3.8% (normal level, 1%–2%), fractional oxygen saturation was 93.9%, partial pressure of oxygen was 327 mmHg, and arterial oxygen saturation was 97.6%. After administration of 1 mg/kg of methylene blue, her SpO 2 improved gradually to 99%, and the methemoglobin value decreased to 1.2%. When using prilocaine as a local anesthetic, it is important to be aware that methemoglobinemia may occur even at doses much lower than the maximum recommended dose.
