Malignant hyperthermia and althesin.

General anaesthesia with Althesin was administered on two occasions to a patient who was identified as susceptible to malignant hyperthermia, in whom there was identified familial subclinical myopathy and once in another patient suffering from arthrogryposis multiplex congenita with a history of fever associated with two previous anaesthetics. In the first patient halothane was administered by accident in association with the Althesin, but no hyperpyrexia occurred. In the second instance nitrous oxide-oxygen and halothane were associated purposely with Althesin. In none of these cases was there any rise in temperature, muscle rigor or elevation of the serum CPK level. This experience corroborates the experimental evidence of Hall, et al.10 and Harrison, who reported that Althesin prevented the onset of hyperthermia, and the clinical reports of Page and Judelman. Althesin can be assumed to be an effective anaesthetic for malignant hyperthermia susceptible patients.