右美托咪定对冠状动脉旁路移植术患者麻醉诱导期BIS和血流动力学的影响

Influence of Dexmedetomidine on Bispectral Index and Hemodynamics during Anesthetic Induction in Chinese Patients Undergoing Coronary Artery Bypass Grafting

目的观察新型α2肾上腺素受体激动剂右美托咪定对冠状动脉旁路移植术（coronary artery bypass grafting,CABG）麻醉诱导期患者脑电双频谱指数（bispectral index,BIS）及血流动力学的影响。方法 2010年6月11日~7月30日30例择期CABG（年龄50~70岁,ASAⅠ~Ⅱ级,心功能Ⅱ~Ⅲ级）随机双盲分为2组：Dex组（n=15）,右美托咪定1μg.kg-1,稀释30 ml静脉泵注（15 min）,继以0.5μg.kg-1.h-1维持输注;对照组（n=15）,生理盐水30 ml,方法同Dex组。监测BIS值,收缩压（systolic blood pressure,SBP）、舒张压（diastolic blood pressure,DBP）、平均动脉压（mean arterial pressure,MAP）、心率（heart rate,HR）,以给药前（T0）、给药后3 min（T1）、6 min（T2）、9 min（T3）、12 min（T4）、15 min（T5）、插管前（T6）、插管结束后1 min（T7）、插管结束后3 min（T8）作为观察记录点。结果麻醉前2组BIS值分别为94.8±2.8和96.3±2.9,无统计学差异（t=-1.441,P=0.161）;与给药前比较,Dex组给药后BIS值逐渐下降,9 min后（T3）下降至84.8±9.7（P=0.034）,15 min后（T5）下降至71.4±13.6（P=0.000）;对照组给药后15 min（T5）BIS值为90.9±4.1,与给药前比较无明显变化,但显著高于Dex组（t=-5.317,P=0.000）。Dex组给药后15 min后（T5）HR明显减慢,由给药前（T0）（64.7±16.4）次/min减至（57.0±11.9）次/min（P=0.024）,但与对照组无明显差异（P〉0.05）;MAP由（101.2±15.1）mm Hg到（100.8±18.8）mm Hg,无明显变化（P=0.927）。麻醉诱导期间,对照组插管后SBP、DBP、MAP、HR值较插管前均有升高,插管后1 min（T7）上述各指标分别为（136.1±36.6）mm Hg（P=0.130）,（75.3±15.5）mm Hg（P=0.000）,（94.4±20.0）mm Hg（P=0.000）,（66.2±13.7）次/min（P=0.009）,插管后3 min（T8）上述各指标分别为（143.5±30.5）mm Hg（P=0.003）,（71.4±12.1）mm Hg（P=0.002）,（92.4±14.8）mm Hg（P=0.002）,（60.1±13.0）次/min（P=0.387）;但Dex组无明显变化（P〉0.05）。结论右美托咪定以负荷剂量1.0μg.kg-1继以0.5μg.kg-1.h-1维持输注对CABG患者产生明显镇静效应,能使BIS值降低,同时降低心率,能维持麻醉诱导期间的血流动力学稳定,减轻插管反应。

Objective To evaluate the influence of dexmedetomidine on bispectral index（BIS） and hemodynamics during anesthetic induction in patients undergoing coronary artery bypass grafting（CABG）. Methods Thirty patients undergoing coronary artery bypass grafting（age 50-70,ASA Ⅰ-Ⅱ,NYHA grade Ⅱ-Ⅲ） were randomly divided（double blinded） into 2 groups： dexmedetomidine group（Dex group,n=15） and control group（C group,n=15）.In Dex group,1.0 μg·kg-1 of Dex was administered intravenously for over 15 minutes,while in C group,same volume of 0.9 % normal saline was given.The BIS,SBP,DBP,MAP,and HR were monitored during the procedure.The above parameters were recorded at the time before dexmedetomidine infusion（T0）,3,6,9,12,and 15 minutes（T1-T5） after loading dose,before endotracheal intubation（T6）,and 1 and 3 minutes（T7 and T8） after endotracheal intubation. Results Demographic data of the patients were similar in both groups.Before anesthesia,the BIS was 94.8±2.8 and 96.3±2.9 respectively in the two groups（t=-1.441,P=0.161）.After loading dose of dexmedetomidine was given and during continuous infusion,BIS increased gradually in Dex group（9 min： 84.8±9.7,P=0.034;15 min： 71.4±13.6,P=0.000）,meanwhile,no significant change was observed in the C group（BIS was 90.9±4.1 at 15 min,which was significantly higher than that in the Dex group,t=-5.317,P=0.000）.At T5,the HR in Dex group decreased significantly from 64.7±16.4/min to 57.0±11.9/min（P=0.024）,but showed no significant difference from the C group;MAP in Dex group decreased from（101.2±15.1） mm Hg to（100.8±18.8） mm Hg（P=0.927）.During Anesthesia induction,C group showed significantly increased SBP,DBP,MAP,and HR [T7：（136.1±36.6） mm Hg,P=0.130;（75.3±15.5） mm Hg,P=0.000;（94.4±20.0） mm Hg,P=0.000;66.2±13.7/min,P=0.009;T8：（143.5±30.5） mm Hg,P=0.003;（71.4±12.1） mm Hg,P=0.002;（92.4±14.8） mm Hg,P=0.002;60.1±13.0/min,P=0.387];meanwhile Dex group showed no significant change. Conclusion Dexmedetomidine with a 1.0 μg·kg-1 loading dose followed by 0.5 μg·kg-1·h-1 maintain infusion causes sedation and decreases HR,which keep hemodynamics stabilization by reducing the response of endotracheal intubation.