ABSTRACT
Malignant hyperthermia (MH) susceptibility is an uncommon inherited disorder of skeletal muscle in which some drugs commonly used in anaesthesia trigger sustained skeletal muscle hypermetabolism. It has an autosomal dominant inheritance, but many cases are sporadic, with less than 25% of patients who experience an MH event having a positive family history. Exposure to a triggering agent is usually necessary but not always sufficient for the susceptible person to experience symptoms. The frequency of MH varies with the patient population, the type of anaesthesia used, and definition of the MH event. The frequency is approximately 1 in 50000 adults, 1 in 15000 children, 1 in 250000 anaesthetics for a fulminant case of MH, and 1 in 6000 for a possible MH event. MH presents with multiple, non-specific, clinical signs of hypermetabolism, and laboratory findings of variable intensity and time course during and after exposure to anaesthetic agents.
