Allen G C, Fletcher J E, Huggins F J, Conti P A, Rosenberg H
Department of Anesthesiology, Hahnemann University, Philadelphia, Pennsylvania 19102-1192.
Anesthesiology. 1990 Jan;72(1):71-6. doi: 10.1097/00000542-199001000-00014.
Caffeine and halothane contracture testing is widely used to detect malignant hyperthermia (MH) susceptibility. The accuracy and reliability of the 3% halothane test and the incremental caffeine test, as recommended by the North American MH Group, were assessed in 11 swine (five MHS, six control). Nine swine were tested twice, 4-6 weeks apart. Accuracy of the in vitro diagnosis was also assessed by in vivo anesthetic challenge. Of all muscle bundles from MH-susceptible swine, 65% reacted positively to 3% halothane and 70% to 2 mM caffeine. Only 35% had a positive caffeine-specific concentration, and 25% developed an increase in baseline tension greater than or equal to 7% at 2 mM caffeine. However, when only the most positive response to 3% halothane or to 2 mM caffeine was used (a minimum of three fresh muscle strips is recommended), these two tests were highly sensitive and specific. In control swine one of 30 muscle bundles reacted positively to 3% halothane. A positive caffeine-specific concentration developed in one of 25 control muscle bundles exposed to caffeine. The variability in the results of these tests mandated that at least three muscle bundles be used for each test. Nonviable muscle bundles could not be relied upon to provide accurate results. In this porcine model, MH susceptibility could be detected by performing the Caffeine Halothane Contracture Test (CHCT) according to the guidelines of the North American MH Group. However, only the 3% halothane test and the response to 2 mM caffeine produced adequate diagnostic results in this breed of swine.
咖啡因和氟烷挛缩试验被广泛用于检测恶性高热（MH）易感性。对11头猪（5头MH易感猪、6头对照猪）评估了北美MH小组推荐的3%氟烷试验和递增咖啡因试验的准确性和可靠性。9头猪在间隔4 - 6周的时间里接受了两次检测。还通过体内麻醉激发评估了体外诊断的准确性。在MH易感猪的所有肌束中，65%对3%氟烷呈阳性反应，70%对2 mM咖啡因呈阳性反应。只有35%有咖啡因特异性浓度阳性，25%在2 mM咖啡因时基线张力增加大于或等于7%。然而，当仅使用对3%氟烷或2 mM咖啡因的最阳性反应时（建议至少使用三条新鲜肌条），这两种试验具有高度敏感性和特异性。在对照猪中，30条肌束中有1条对3%氟烷呈阳性反应。在25条暴露于咖啡因的对照肌束中有1条出现咖啡因特异性浓度阳性。这些试验结果的变异性要求每次试验至少使用三条肌束。不能依靠无活力的肌束来提供准确结果。在这个猪模型中，根据北美MH小组的指南进行咖啡因氟烷挛缩试验（CHCT）可以检测到MH易感性。然而，在这个品种的猪中，只有3%氟烷试验和对2 mM咖啡因的反应产生了足够的诊断结果。
