Malignant hyperthermia

Last updated: Friday, 06, August, 2010
Key InformationAppropriate Tests

Muscle biopsy. Screening with creatine kinase(CK) is possible in some families but false negatives may occur.

The definitive test is the caffeine-halothane contracture test, which is performed in only a few specialised centres.

Inherited as an autosomal dominant (50% of cases) or autosomal recessive (20%), but affects males more frequently than females.

History of an uneventful anaesthetic does not exclude a subsequent attack.

The syndrome occurs in association with a number of specific genetic myopathies, but most cases are due to an undefined genetic cause.

A few of these are due to mutations in the ryanodine receptor.


  • Central core disease
  • Duchenne/Becker muscular dystrophy
  • Periodic paralysis
  • Mitochondrial myopathy
  • Myotonia congenita

Acute episode: 
Muscle rigidity, tachycardia, rapid increase in body temperature.

Electrolytes (potassium), creatine kinase (CK), urea, creatinine; myoglobin - urine; blood gases.

See also DIC.