中文摘要：

目的：观察在瑞芬太尼靶控输注下，患者意识消失时丙泊酚的效应室浓度。方法：全身麻醉患者分为瑞芬太尼＋丙泊酚组（RP）和单纯丙泊酚组（P）。RP组给予瑞芬太尼靶控输注，待瑞芬太尼效应室浓度达到4ng／mL时开始丙泊酚靶控输注，靶控输注浓度为血浆浓度4μg／mL。P组单纯按4μg／mL给予丙泊酚靶控输注。记录患者意识消失时的丙泊酚效应室浓度。结果：瑞芬太尼靶控输注下，令患者意识消失的丙泊酚效应室浓度ECe50值为0．84（0．75，0．93）μg／mL，ECe95值为1．40（1．27，1．59）μg／mL。单纯靶控输注丙泊酚则分别为1．9（1．83，1．98）μg／mL和2．8（2．72，2．94）μg／mL。两组ECe50值和ECe95值均有统计学差异（P均〈0．05）。RP组患者意识消失的时间和丙泊酚用量均明显低于P组，Narcotrend指数则高于P组，平均动脉压降低也较P组严重（P均〈0．05）。结论：瑞芬太尼可增强丙泊酚的镇静效果，降低令患者意识消失的丙泊酚效应室浓度。

英文摘要：

AIM： To determine the influence of remifentanil on effect site concentration of propofol for loss of consciousness. METHODS： Patients scheduled for general anesthesia were randomly enrolled into group RP and group P. Group RP received target controlled infusion ofremifentanil until an effect site concentration of 4 ng/mL was achieved. Then propofol was in- fused with a target plasma concentration of 4 /μg/mL. Group P received infusion of propofol of the same target concentration. The effect site concentration of propofol for the patient losingconsciousness was recorded. RESULTS： For the group RP, the ECe50 of propofol effect site con- centration for patients losing consciousness was 0. 84（0. 75,0. 93） μg/mL,while the ECe95 value was 1.40（1.27,1.59） μg/mL. However, for the group P, the ECe50 value was 1. 9（1.83,1. 98） /μg/mL and the ECe95 value was 2.8（2.72, 2.94） μg/mL. There were significant differ- ences between the two groups considering both the two values （both P〈0.05）. Time to LOC and propofol needed to lower in the RP group, LOC was significantly while Narcotrend indexwas higher. Furthermore, the decrease of MAP was more significant in the RP group （all P〈0.05）. CONCLUSION. Remifentanil could in- crease the sedative effect of propofol and de- crease the effect site concentration of propofol for loss of consciousness.