异丙酚的剂量与镇静和呼吸抑制作用之间的关系

The relation of propofol between dosage and the effects of sedation and respiratory depression

研究不同剂量的异丙酚的量效关系。方法:选择50例甲状腺腺瘤切除病人,随机分为5组,Ⅰ组,0.5mg/kg、Ⅱ组0.75mg/kg、Ⅲ组1.0mg/kg、Ⅳ组1.5mg/kg、V组2.0mg/kg.采用Star呼吸机监测呼吸功能指标,同时观察其神志变化,应用Probit法分析该药量效关系。结果:Ⅱ、IV、V组随着剂量增加,潮气量降低的幅度和呼吸抑制持续时间明显增加,以给药后1～3分钟潮气量减少最为明显(P<0.01),浅睡状态ED_(50)为0.98mg/kg.深睡状态ED_(50)为1.26mg/kg,呼吸抑制ED_(50)为1.1mg/kg。结论:静注0.8～1mg/kg异丙酚可以产生适用于非全麻病人的镇静、催眠作用,而对呼吸抑制的作用较小。

Objective:To observe the relation of propofol between dosage and clinical effect during induction of anesthesia. Method: Fifty patients with adenoma of thyroid for subtotal thyromactomy undergoing cervical plexus block were randomly allocated to receiving one of five different doses of propofol 0.5mg/kg(groupⅠ),0.75mg/kg (group;Ⅱ), 1.0mg/kg(group Ⅲ), 1.2mg/kg(group Ⅳ)and 2.0mg/kg(group Ⅴ ). Respiratory function was monitored with Star ventilator while mental changes was observed. ED_(50) and ED_(95) for loss of consciousness and respiratory depression were determined using Probit analysis. Result:Tidal volume decreased but the time of respiratory depression increased in group Ⅰ,Ⅳ,and Ⅴ more than those in Ⅰ group, particularly 3-5 minutes after intravenous propofol. ED_(50) for asleep, anaesthesia,and respiratory depression were at 0.98mg/kg, 1.26mg/kg,and 1.1mg/kg respectively. Conclusion:Propofol has satisfactory sedative and hypotic effect with minimal respiratory depression at the dose of 0.8-1.0mg/kg for the patients under regional anesthesia.