Toxic Methemoglobinemia Caused by Prilocaine: Presentation of Two Cases

Abstract

Prilocaine is a local anesthetic agent used in many areas, but it may cause the methemoglobinemia, a life-threatening side effect. As a result, hypoxia may develop in the tissues. In this study, two toxic methemoglobinemia cases are presented since they develop depending on the local prilocaine used during the invasive intervention by radiology. Methemoglobinemia is a serious hematological disease and occurs when iron in hemoglobin is oxidized and becomes trivalent (Fe+++). Methemoglobinemia should be brought to mind in the differential diagnosis in the case of determining nonconcurrence or cyanosis between PaO2 and SaO2 values after using a local anesthetic. In such circumstances, it is appropriate to monitor patients in fully equipped intensive care units in terms of problems that may develop. Methylene blue and ascorbic acid were successfully used in treatment. In this paper, two cases are presented since methemoglobinemia developed depending on the use of prilocaine for local anesthesia and they were treated by intravenous methylene blue and/or ascorbic acid.