右美托咪定对下腹部手术患者异氟醚呼气末有效浓度的影响

摘要

目的 以脑电双频指数(BIS)为麻醉镇静深度指标,探讨右美托咪定(Dex)的不同输注速率对下腹部手术患者异氟醚呼气末有效浓度的影响.方法 妇科剖腹手术患者60例,ASA Ⅰ或Ⅱ级,随机均分为:生理盐水对照组(C组),Dex 0.4μg/kg组(D1组):Dex负荷量0.4μg/kg+维持量0.4 μg·kg-1·h-1,Dex 0.8μg/kg组(D2组):Dex负荷量0.8 μg/kg+维持量0.8μg· kg-1 ·h-1.三组负荷量药物均以微量泵于麻醉诱导前在10 min内泵注完毕.麻醉诱导:静注丙泊酚1～3mg/kg、芬太尼3μg/kg、维库溴铵0.12 mg/kg,当BIS＜ 55时行气管插管.术中根据BIS值变化调节异氟醚吸入浓度维持BIS在40～55.术中持续监测血流动力学变化、异氟醚吸入和呼气末浓度.结果 术中及术毕D1、D2组异氟醚呼气末浓度均明显低于C组(P＜0.05或P＜0.01),且D2组明显低于D1组(P＜0.05).与C组比较,气管插管及拔管时D1组及D2组血流动力学更稳定.结论 以BIS值为监测标准,Dex能有效降低异氟醚呼气末浓度,提高围术期血流动力学稳定性,未见严重不良反应.%Objective To investigate the effects of dexmedetomidine on end-tidal isoflurane concentration with bispectral index (BIS) as the index of depth of anesthesia Methods Sixty patients undergoing elective lower abdominal surgery received general anesthesia, ASA I or II , were randomly divided into three groups: group C received a saline infusion, group Di received Dex loading 0. 4 /Mg/kg for 10 min,maintenance 0. 4 jig-kg"1 ?h~'; group D2 received Dex loading 0. 8 fig/kg for 10 min, maintenance 0.8 fig "kg"1 -h"1. And then intravenous injection of propofol 1-3 mg/kg, fentanyl 3 /Ltg/kg and vecuronium 0. 12 mg/kg. When the BIS<55, patients were received tracheal intubation and mechanical ventilation. The concentration of isoflurane was adjusted according to BIS. HR, MAP and end-tidal isoflurane concentation were continuously monitored. Results When BIS was maintained between 40 and 55, the end-tidal isoflurane concentration of group Di and group D2 were lower than that in group C(P<0. 05 or P