Malignant hyperthermia-triggering liability of selected inhalant anesthetics in swine.

Twenty pigs, known to be malignant hyperthermia (MH)-susceptible by previous MH-positive [MH(+)] reactions to halothane testing, were given 5 inhalant anesthetics. The number of MH(+) responses evoked by the different anesthetics varied. In response to halothane, isoflurane, and enflurane, MH(+) reactions were exhibited by 12, 11, and 7 pigs, respectively. The number of MH(+) reactions to nitrous oxide (0) and methoxyflurane (1) was significantly (P = 0.02) less. In the present study, all 4 halogenated-hydrocarbon volatile liquid inhalant anesthetics were capable of evoking a MH(+) reaction in susceptible pigs.