MALIGNANT HYPERTHERMIA

Malignant hyperthermia (MH) is a rare, life-threatening pharmacogeneti c disease. The genetic incidence is estimated to be 1:10 000. In predi sposed individuals, MH is triggered by volatile anaesthetics and/or de polarizing muscle relaxants by an abnormal increase of intracellular c alcium concentration in skeletal muscle cells. The clinical presentati on may vary from abortive MH to the fulminant MH crisis. Early diagnos is, the use of electrocardiography and capnography for anaesthetic mon itoring, immediate cessation of trigger agents and dantrolene treatmen t are essential components of an effective MH therapy. In some MH fami lies, a genetic alteration of the ryanodine receptor gene (a calcium c hannel of the sarcoplasmic reticulum) on chromosome 19 has been identi fied as the potential cause of MH susceptibility. Recent molecular bio logical findings support the view of MH being a heterogenetic disease. At present, the diagnosis in potentially MH-susceptible individuals i s still made using the in vitro halothane and caffeine muscle contract ure test.