[Hyperlactemia during undiagnosed pheochromocytoma resection under laparoscopy].

A 51-year-old man was scheduled to undergo adrenal tumor resection. Because his general physical findings and labolatory tests were not particular, and his serum concentrations of noradrenaline and adrenaline were within normal limit, the tumor was diagnosed as nonfunctional adrenal tumor. Anesthesia was induced with propofol, fentanyl and maintained with oxygen, air, propofol and remifentanil. When the surgeons started to work around the tumor, his blood pressure and heart rate increased suddenly. We decided to deal with the tumor as pheochromocytoma and started administering landiolol and prostaglandin E1. After the administration of the drugs, hemodynamic changes became stabilized; however, the increasing serum concentration of lactate continued until ligation of the adrenal vein. There were no clinical manifestations of circulatory failure and his liver function was within normal limits from his blood test. After the operation, we found his plasma concentration of adrenaline extremely high during the operation. Adrenaline increases blood lactate concentration due to metabolic effects. Hyperlactemia should be considered as one of the typical symptoms of pheochromocytoma.