[Anesthesia for a patient with mitochondrial respiratory chain complex III deficiency].

Mitochondrial myopathies make up a group of rare disorders whose onset is in childhood or adolescence. Muscle and central nervous system involvement is variable. Mitochondrial respiratory chain complex III deficiency (coenzyme Q - cytochrome C reductase) can manifest as exercise intolerance, myopathy, encephalopathy, and myocardial disease. Approximately 38 patients with complex III deficiency have been described since 1966, yet only a single anesthetic experience (epidural analgesia for cesarean delivery) has been reported. We describe the case of an 11-year-old boy with mitochondrial respiratory chain complex III deficiency, severe myopathy, and moderate encephalopathy who underwent surgery to improve right ischiotibial muscle spasticity. Monitoring included electrocardiography, noninvasive blood pressure, oxygen saturation by pulse oximetry, end-tidal carbon dioxide pressure, esophageal temperature, spirometry, and neuromuscular block (Relaxograph Datex). Midazolam, fentanyl, and propofol were used for anesthetic induction; mivacurium was used during intubation. Anesthetic maintenance was with propofol in continuous infusion and fractionated doses of fentanyl and mivacurium on demand in a mixture of oxygen and air. The boy's response to mivacurium was abnormal but he could nevertheless be extubated in the operating room at a train-of-four ratio of 75% and with no need to reverse the neuromuscular blockade. There were no problems during the anesthetic procedure, so it could be a good technique for these patients, despite of considering individually every case and extension of syntomatology, due to the little experience in anesthesia with deficiency of Complex III.