[Central hyperthermia suspected of malignant hyperthermia in a patient undergoing radical neck clipping for cerebral aneurysm].

A 45-year-old woman underwent radical neck clipping for cerebral aneurysm under isoflurane anesthesia. Her preoperative examination revealed elevated body temperature which had been normal on admission. Her body temperature increased up to 40.3 degrees C during anesthesia and surgery, and it showed a downward trend at the end of surgery. Malignant hyperthermia was excluded because the patient did not have metabolic acidosis, hypercarbia, hyperpotassemia or abnormal sweating anesthesia. The patient received intravenous dantrolene postoperatively since there was a suspicion of malignant hyperthermia on the basis of hyperthermia and increases in serum creatine kinase (CK) and myoglobin (Mb) levels. Her body temperature and serum CK and Mb levels decreased for a while after administration of dantrolene, but they increased again thereafter. The patient was aggressively cooled with a cooling blanket and hyperthermia and increases in serum CK and Mb levels disappeared in postoperative two weeks. She was discharged on foot without any neurological deficit on the forty-third hospital day. According to the diagnostic criteria for malignant hyperthermia by Larach and his colleague, malignant hyperthermia was somewhat less than likely in our case. The clinical course of the patient also suggested that a possibility of malignant hyperthermia was considerably low. The authors conclude that perioperative hyperthermia in our case must have derived from central hyperthermia following subarachnoid hemorrhage, and that postoperative increases in serum CK and Mb levels might have resulted from acceleration of sympathetic nervous system by subarachnoid hemorrhage.