[Anesthetic management for a patient with citrullinemia and liver cirrhosis].

We successfully anesthetized a 53-year-old female with hypercitrullinemia and severe liver cirrhosis. The hypercitrullinemia was accompanied with chronic hepatic encephalopathy due to hyperammonemia, which resulted from decreased activity of one of the urea cycle enzymes, argininosuccinate synthetase (ASS). She was scheduled for replacement arthroplasty of a fractured femoral neck. She suffered a consciousness disturbance due to hyperammonemia, which was successfully treated by oral administration of sodium benzoate before surgery. Spinal anesthesia was chosen because it would have the minimum metabolic load on the cirrhotic liver. During the operation, prostaglandin was continuously infused to maintain hepatic blood flow. Acetated Ringer solution was infused instead of lactated Ringer solution to reduce metabolic load on the liver. She was given a small dose each of fentanyl and midazolam for relief of pain and sedation. After the operation, naloxone and flumazenil were administered to antagonize the fentanyl and midazolam, respectively. Although the serum ammonia level temporarily increased during a postoperative interruption of oral administration of sodium benzoate, the patient did not develop loss of consciousness, which is a key sign of hyperammonemia. Surgery and anesthesia were uneventfully completed.