Anesthetic management of a patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) during laparotomy.

A 53-year-old man with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) underwent a gastrectomy. We administered bicarbonated Ringer's solution, which has a physiological concentration of bicarbonate. The level of serum lactate did not increase significantly, and metabolic acidosis did not occur throughout surgery or for 3 h after surgery. Aggressive warming was needed to maintain normothermia, presumably because the mitochondrial respiratory chain, which is responsible for thermogenesis, is impaired in MELAS patients. It is important to maintain normothermia in MELAS patients in order to avoid further mitochondrial metabolic depression.