[The use of propofol combined with nitrous oxide and fentanyl in anesthetic management of a patient with mitochondrial encephalomyopathy].

A 49-year-old female with mitochondrial encephalomyopathy underwent surgery for implantation of an artificial cochlear device. She had some characteristic clinical features, including muscle weakness, deafness and dementia. Anesthesia was induced with 5 mg.kg-1 of propofol, and the trachea was intubated without a muscle relaxant. The patient was mechanically ventilated also without a relaxant, and anesthesia was maintained with a continuous infusion of 4-8 mg.kg-1.hr-1 of propofol, a bolus injection of 50-100 micrograms of fentanyl, and nitrous oxide (66%) in oxygen (33%). Bispectral index (BIS) was monitored and maintained at approximately 40. No cardiovascular instabilities or increase in plasma lactate concentration were observed during surgery. The patient had a smooth recovery from the propofol anesthesia, and the BIS value returned to the pre-anesthetic level 10 min after completion of the anesthesia, suggesting that the use of propofol is a safe means for inducing and maintaining anesthesia in patients with mitochondrial encephalomyopathy.