Postoperative malignant hyperthermia and dantrolene therapy

A case of malignant hyperthermia (MH) in a three-year eight-month-old girl is presented. Definite symptoms of MH developed in the awake patient 30 min after termination of anaesthesia which had lasted five hours. This postoperative MH-episode resolved promptly following intravenous administration of dantrolene (2.5 mg X kg-1 initially, followed by 5 mg X kg-1 over 12 hours). Results of serial serum samples revealed a steady increase in creatine kinase (CK) concentration with the highest value being observed at the second day, despite dantrolene therapy. The unusual occurrence of MH in the postoperative period, when the major effects of anaesthesia were no longer an important consideration, is discussed with regard to the "human stress syndrome." The necessity to give this information to people usually not familiar in diagnosing MH (e.g., medical personnel in surgical wards) is stressed.