Methemoglobinemia Due to Prilocaine Under Endoscopic Throcal Sympathectomy

Prilocain is a common local anesthetic that has been used for many procedures. However, it can cause methemoglobinemia which is a rare and fetal complication. Twenty two years old patient who was undergone bilateral enoscopic throcal sympathectomy (ETS) under seoanalgesia, developed cyanosis at preioral and nail fold region, 5 minutes after the administraion of prilocain. Resistance hypoxemia (SpO2:80% and PO2:93 mmhg) persisted despite 6 lt/min O2 support via face mask and patient was taken to Intensive Care Unit with a prediagonsis of methemoglobinemia. Glucose-6-phosphate dehydrogenase enzyme levels, other labarotary evaluations and chest radiography revealed normal. Patient was hydrated with 5% dextrose. Patient was oxygenated with 4 lt/min O2 oxygen via face mask. Intravenous methylene blue could not be provided, therefore ascorbic acid infusion was administered. Arterial blood PO2 and methemoglobinemia levels were improved during follow up period. Peripheral and preioral cyanosis were disappeared and MetHb levels were %4.5 and pO2 were 169 mmhg, 8 hours after the operation. As a result, succesfull treatment of the patient was accomplished through early recognition of methemoglobinemia with the symptoms of cyanosis and resistance hypoxemia