七氟醚和安氟醚对维库溴铵增效作用的时间依赖性

目的 :观察最低肺泡有效浓度 (1MAC)七氟醚和安氟醚对维库溴铵增效作用的时间依赖性。方法 :4 0例择期手术病人在异丙酚 芬太尼 N2 O麻醉期间持续输注维库溴铵 ,维持 90 %的肌松 ,达到稳态后 ,病人随机吸入1MAC呼气末浓度的七氟醚或安氟醚 ,调整维库溴铵的注入速率 ,维持 90 %的肌松 ,观察吸入七氟醚或安氟醚后维库溴铵的注入速率随时间变化的趋势。结果 :七氟醚、安氟醚都显著降低了维库溴铵的注入速率。并且这个效应随着吸入七氟醚或安氟醚时间的延长逐渐增加 ,吸入七氟醚或安氟醚 90min后达到最大效应即维库溴铵的注入速率下降到最大值。最大下降率 :七氟醚组为 6 8% ,安氟醚组为 6 7%。结论 :七氟醚、安氟醚都明显增强维库溴铵的肌松作用 ,但这种增效作用有显著的时间依赖性。两者之间无显著性差异 (P >0 0 5 )。

Time Course of Potentiation of Vecuronium by Sevoflurane and Enflurane

Objective: Our aim was to observe the time dependent course of potentiation of vecuronium produced by 1MAC end tidal sevoflurane and enflurane. Methods: At the beginning , a steady infusion rate of vecuronium to maintain 90% of neuromuscular block was established in 40 patients undergoing neurosurgical procedures under propopol fentanyl nitrous oxide oxygen anaesthesia. The patients were randomly assigned to 2 groups which received 1MAC end tidal concentration of either sevoflurane(Group Sev)or enflurane(Group En).Vecuronium infusion rate was adjusted to maintain neuromuscular block by 90 percent. The change of infusion rate of vecuronium with time was observed after inhalation of sevoflurane or enflurane. Results: Sevoflurane and enflurane decreased the infusion dosage of vecuronium in an exponential manner in that maximal potentiation occurred only after 90 minutes.Maximal reduction in infusion rate was 68% in group sevoflurane and 67% in group enflurane without the significantdifferencebetweenthem. Conclusion: Sevofluraneand enflurane can potentate the muscular relaxation of vecuroniuminsimilardegree,and the potentiation was strongly time dependent.