Department of Anaesthesiology, University Würzburg, Würzburg, Germany.
Eur J Anaesthesiol. 2011 Apr;28(4):251-5. doi: 10.1097/EJA.0b013e32833ed06c.
Malignant hyperthermia is a potentially lethal inherited hypermetabolic syndrome that develops in susceptible individuals following administration of depolarising neuromuscular relaxants or volatile anaesthetics. Genetic analysis can only confirm a diagnosis of malignant hyperthermia in about 70%, and in the remainder an in-vitro contracture test, with halothane and caffeine, on muscle obtained from open muscle biopsy is required to establish the diagnosis. As the licence for clinical use of halothane expired in 2005, its continuing availability is in doubt. More modern volatile anaesthetics such as enflurane, isoflurane, desflurane and sevoflurane are less potent triggers of malignant hyperthermia in humans and pigs. The aim of this study was to investigate whether these agents can be considered possible substitutes for halothane in a modified in-vitro contracture test.
With institutional review board approval and prior written consent, muscle bundles of 30 patients with a personal or family history of malignant hyperthermia were investigated. Of these, 13 were diagnosed malignant hyperthermia susceptible and 17 nonsusceptible. Surplus muscle was tested with increasing concentrations of enflurane, isoflurane, desflurane and sevoflurane.
There were no differences in weight, length or predrug tension of the muscle bundles. At increasing concentration, all volatile anaesthetics except sevoflurane induced significantly greater contractures in malignant hyperthermia susceptible compared to malignant hyperthermia nonsusceptible muscle. In malignant hyperthermia susceptible muscle bundles, halothane led to significantly higher contractures compared to the other investigated substances.
Halothane was the strongest discriminator for malignant hyperthermia in the in-vitro contracture tests. It remains the ideal substance for diagnostic testing and cannot simply be replaced by other agents in this test.
恶性高热是一种潜在致命的遗传性代谢亢进综合征，易感性个体在使用去极化神经肌肉松弛剂或挥发性麻醉剂后会发生。基因分析只能确认约 70%的恶性高热诊断，其余的则需要进行体外收缩试验，使用来自开放肌肉活检的肌肉，用卤烷和咖啡因，以建立诊断。由于卤烷的临床使用许可证已于 2005 年到期，其继续供应存在疑问。更现代的挥发性麻醉剂，如恩氟烷、异氟烷、地氟烷和七氟烷，在人类和猪中引发恶性高热的能力较弱。本研究旨在探讨这些药物是否可在改良的体外收缩试验中被视为卤烷的可能替代品。
经机构审查委员会批准和事先书面同意，对 30 名有恶性高热个人或家族史的患者的肌肉束进行了研究。其中，13 名被诊断为恶性高热易感，17 名非易感。用递增浓度的恩氟烷、异氟烷、地氟烷和七氟烷测试剩余的肌肉。
肌肉束的重量、长度或预用药张力无差异。在递增浓度下，除七氟烷外，所有挥发性麻醉剂在恶性高热易感肌肉中引起的收缩均明显大于恶性高热非易感肌肉。在恶性高热易感肌肉束中，与其他研究物质相比，卤烷导致的收缩明显更高。
在体外收缩试验中，卤烷是恶性高热的最强鉴别剂。它仍然是诊断测试的理想物质，在该测试中不能简单地被其他物质替代。
