Influence of nutrition on malignant hyperthermia in pigs.

In 2 experiments malignant hyperthermia susceptible Danish Landrace pigs were fed, for 2 or 4 weeks, synthetic diets containing casein as protein source or no protein. Minerals and vitamins were supplied to both groups. The animals were anaesthetized weekly for a maximum of 20 min with a halothane-oxygen mixture. In the first experiment malignant hyperthermia was equally delayed in both groups. If malignant hyperthermia developed, the appearance was at the end of the anaesthetic period. In the second experiment a deeper anaesthesia was employed. Malignant hyperthermia was delayed in both groups, but most markedly in the protein-deficient animals. Malignant hyperthermia developed faster after return to the original feed. These results provide evidence for a nutritional influence on the penetrance of malignant hyperthermia susceptibility during halothane anaesthesia in pigs.