靶控输注异丙酚复合瑞芬太尼对老年患者脑电双频指数的影响

摘要

Objective In this prospective randomized study, we compared the EC50~95 for propofol and the Bispectral Index ( BIS) values at loss of consciousness ( LOC) and response to a standard noxious painful stimulus in elderly and adult patients respectively. Method There were 102 ASA Ⅰ ~II patients undergoing elective surgery under general anesthesia were enrolled in this study, whom were divided into adult group (aged 18~64 yrs, n=52) and eldly group (age≥65yrs, n= 52). TCI Propofol was started at target plasma concentration (Cp)of 1. 2μg/ml and increased by 0. 3μg/ml every 30 s until loss of consciousness(LOC). Keep the target effect-site concentration (Ce) of propofol at LOC, TCI remifentanil was started at Cp of 2. 0 ng/ml, increased by 0. 3 ng/ml every 30 s until loss of somatic response to a tetanic stimulus (50Hz, 80mA, 0. 25ms, 4s). Cp, Ce, BIS, SBP, DBP, MAP and HR were recorded. The Ce of propofol and BIS at LOC and at loss of somatic response to noxious stimulus in 50% ~95% of the patients ( EC50~95 ,BIS50~95 ) , and 95% Confidence Interval were determined by Probit method. To ex-plore the adjustment required for TCI propofol with remifentanil in elderly patients. Result In elderly group, the propofol EC50 ~95 at LOC was (1. 5~2. 0μg/ml),significantly lower than that in adult group (2. 2 ~2. 9μg/ml) (P<0. 01). There was no statistical differences in BIS values between elderly and adult patients at LOC and no so-matic response to tetanic. Conclusion For TCI propofol and remifentanil in elderly patients, the requirement of Ce of propofol need to be decreased than that of adult patients significantly, but the changes of BIS for elderly were similar with adult patients.%目的比较老年和青壮年患者靶控输注异丙酚和瑞芬太尼,在意识消失和疼痛反应消失时脑电双频指数的变化。方法拟行全麻患者共104例,青壮年组(18~64岁)和老年组(≥65岁)各52例,ASAⅠ~II级。靶控输注(TCI)异丙酚预计血浆浓度(Cp)从1.2μg/ml开始,每30秒升高0.3μg/ml,直至意识消失,维持异丙酚意识消失时的效应室浓度( Ce)不变,同时 TCI 瑞芬太尼 Cp=2.0ng/ml,每30秒升高0.3ng/ml,以50Hz,80mA,0.25ms,4秒的强直刺激为疼痛刺激,以此刺激不能引起体动反应作为疼痛消失的终点,记录各时点异丙酚的Cp、Ce、脑电双频指数( BIS)、收缩压( SBP)、舒张压( DBP)、平均动脉压( MAP)和心率( HR),计算青壮年组和老年组在意识消失时异丙酚效应室浓度以及对疼痛刺激反应消失时BIS50~95及95%可信区间,探讨靶控输注异丙酚伍用瑞芬太尼对老年患者BIS的影响。结果老年组意识消失时异丙酚EC50~95为1.5~2.0μg/ml 明显低于青壮年组2.2~2.9μg/ml,但两组患者在意识消失和对疼痛刺激体动反应消失时的BIS50~95时差异无显著性。结论老年患者在意识消失所需异丙酚浓度明显低于青壮年,在意识消失和对疼痛刺激体动反应消失时的BIS值并没有差异。