小剂量氯胺酮对靶控输注异丙酚全麻时BIS值的影响

EFFECTS OF LOW-DOSE KETAMINE GIVEN INTRAVENOUSLY ON BIS DURING TOTAL INTRAVENOUS ANESTHESIA WITH PROPOFOL

①目的观察静脉输注小剂量氯胺酮对靶控输注(TCI)异丙酚全麻时脑电双频指数(BIS)值及血流动力学参数影响。②方法将40例择期手术病人随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ组。麻醉诱导前直接启动异丙酚TCI,每3 min行警觉-镇静(OAA/S)评分一次,并记录BIS值,根据OAA/S评分和BIS值调整异丙酚TCI,直到OAA/S评分达1分时维持异丙酚TCI,各组分别静脉推注氯胺酮0、0.1、0.2、0.4 mg/kg,记录每次评分时刻的BIS值、心率、平均动脉压。分析用药前后BIS值和血流动力学参数变化。③结果Ⅰ、Ⅱ、Ⅲ组用氯胺酮前后BIS值、心率、平均动脉压差别均无统计学意义(P>0.05)。Ⅳ组用氯胺酮后3 min时BIS值比用药前增高(P<0.05),6 min时BIS值恢复至用药前水平(P>0.05)。④结论靶控输注异丙酚全麻时,静脉输注小剂量氯胺酮对BIS值的影响与剂量相关,静脉输注≤0.2 mg氯胺酮对BIS值无影响,提示异丙酚伍用小剂量氯胺酮静脉麻醉时,BIS值可作为异丙酚靶控输注的反馈控制变量。

Objective To detect the effects of ketamine given intravenously on BIS during total intravenous anesthesia with Propofol. Methods Forty patients（ASA grade Ⅰ , Ⅱ ） undergoing elective surgery were randomly divided into four groups. The patients were given target controlled infusion anesthesia with Propofol. The depth of sedation was assessed using OAAS scale at three-minute intervals. TCI concentration was adjusted according to OAAS scale to OAAS scale 1, and the concentration was maintained. Ketamine 0, 0.1, 0.2, 0.4mg/kg was given intravenously to the patients in groups Ⅰ , Ⅱ , Ⅲ ,Ⅳ respectively. BIS, MAP and HR were continuously monitored. The differences between before and after medication were determined in each group. Results There were no significant differences among the four groups with respect to age, body weight, or sex. There were no significant changes between before and after injection in BIS, MAP and HR in groups Ⅰ , Ⅱ , Ⅲ. There was an increase in BIS in group IV, but no significant changes in MAP and HR. Conclusion Ketamine ≤0.2mg given intravenously has no effects on BIS during total intravenous anesthesia with Propofol. BIS can be used as a feedback control when low-dose ketamine was given intravenously during total intravenous anesthesia with propofol.