中文摘要：

目的研究全凭静脉麻醉诱导前预注小剂量右美托咪定对腹腔镜胆囊切除患者拔管期脑电双频（B1S）指数和复苏情况的影响。方法64例行择期腹腔镜下胆囊切除手术患者随机分为右美托咪定组（D组）和对照组（c组），各32例。全麻诱导前，D组微量泵缓慢静注右美托咪定0．5μg／kg，C组给予等量生理盐水，10min注射完毕。所有患者采用丙泊酚-瑞芬太尼靶控输注（TC1）全凭静脉麻醉，术中常规生命体征监测。记录患者术前（TO）、停TCI即刻（T1）、停TCI后5min（T2）、自主呼吸恢复（T3）、神志恢复（T4）、拔管口5）及拔管后5min（T6）的BIS指数。分别记录停TCI至BIS达65、75、85、95及呼吸恢复、神志恢复、拔管的时间。比较拔管即刻至拔管后20min患者不良反应发生情况。结果（1）D组T2-T3时BIS值低于C组（P〈0．05），T4--T6时与C组无统计学差异（P〉0．05）。（2）D组BIS值达到65、75的时程明显长于C组（P〈0．05），但D组BIS值达到85和95，以及呼吸恢复、神志恢复、拔管时间与c组无统计学差异（P〉0．05）。（3）拔管期，D组呛咳、躁动、恶心、呕吐、循环波动发生例数明显少于C组（P〈0．05）。结论麻醉诱导前预注小剂量右美托咪定，不影响腹腔镜胆囊切除患者术毕的清醒程度和复苏时间，且有利于减少拔管期不良反应。

英文摘要：

Objeotive To study the effects of dexmedetomidine preinjection before total intravenous anesthesia induction on bispectral （BIS） index and recovery in patients receiving laparoscopic cholecystectomy （LC） during extubation period. Methods Total 64 patients receiving LC were randomly divided into dexmedetomidine group （group D） and control group （group C） （n=32 per group）. Before total intravenous anesthesia induction, small doses of dexmedetomidine were injected by micro pumps in group D （0.5 μg/kg）, and normal saline was administered in group C within 10 rain. All patients were treated with propofol-remifentanil target controlled infusion （TCI） for total intravenous anesthesia, and intraoperative routine life signs monitoring was provided. The BIS index was recorded before operation （TO）, upon stop of TCI （T1）, in 5 min after stop of TCI （T2）, upon recovery of spontaneous breathing （T3）, upon recovery of consciousness （T4）, during extubation （T5） and in 5 rain after extubation （T6）. The time period from the stop of TCI to that when BIS index reached to 65, 75, 85, and 95 and the time points of respiration recovery, extubation, and consciousness recovery were recorded, respectively. The incidences of adverse reactions of patients within 20 min after the extubation were compared between two groups. Results （1）The BIS values in group D from T2 to T3 were lower than that in group C （P 〈 0.05）, and those from T4 to T6 had no significant difference from those in group C （P 〉 0.05）. （2） The time periods for BIS values in group D to reach to 65 and 75 were longer than those in group C （P 〈 0.05）, but those for BIS values in group D to reach to 85 and 95 as well as the time points of respiration recovery, extubation, and consciousness recovery showed no significant difference from those in group C （P 〉 0.05）. （3） During the extubation period, the incidences of cough, restlessness, nausea and vomiting, and cycle fluctuations in gro