右美托咪定镇静时BIS与OAA/S评分的相关性研究

The correlation study of BIS and OAA/S when sedated with dexmedetomidine

目的探讨右美托咪定镇静时BIS与OAA/S评分的相关性。方法选择腰-硬联合麻醉下行单侧膝关节镜手术患者60例,ASAⅠ或Ⅱ级。随机分为三组:右美托咪定组(D组)、丙泊酚组(P组)和咪达唑仑组(M组),每组20例。每组镇静药物均连续三阶段输注,每阶段维持40min。D组:第一阶段负荷量加维持量,负荷量1.0μg/kg,15min恒速输注完毕,维持量0.5μg·kg-1·h-1,第二、三阶段维持量分别为1.0、1.5μg·kg-1·h-1。P组:三阶段效应室靶控浓度分别为1.0、2.0、4.0μg/ml。M组:三阶段药物浓度分别0.05、0.1、0.15mg·kg-1·h-1。三组药物输注的120min内,每隔5分钟记录一次BP、HR、SpO2、BIS值,分析OAA/S评分与BIS的相关性(r)和BIS对OAA/S评分的预测概率(Pk)。结果与基础值比较,OAA/S评分≤3时三组SBP明显降低、OAA/S评分≤4分时D组HR明显减慢(P<0.05)。与D组比较,OAA/S评分≤3分时M组SBP明显升高、OAA/S评分≤4分时P组和M组HR明显增快(P<0.05)。与OAA/S评分5分时比较,OAA/S评分≤4分时三组患者BIS明显降低(P<0.05)。与D组比较,OAA/S评分≤4分时P组和M组BIS值明显升高(P<0.05)。三组患者BIS与OAA/S评分呈正相关,且Pk值均大于0.5(P<0.05)。结论右美托咪定镇静时BIS与OAA/S评分具有较好相关性,可作为评价右美托咪定镇静深度的重要指标;但其相关性较丙泊酚、咪达唑仑差。

Objective To assess the accuracy of application of bispectral index in monitoring sedation with dexraedetomidine. Methods Sixty ASA Ⅰ or Ⅱ patients undergoing knee arthroscopy with combined spinal-epidural anesthesia were enrolled in the study. The patients were randomly divided into three groups： group D（n=20）： group dexmedetomidine; group P（n=20）： group propofol; and group M（n=20） ： group midazolam. The sedative drugs were adminstered 5 minutes before operation. Group D： The loading dose of dexmedetomidine was administered for 15 min（1 μg/kg）, and the maintenance dose of the first step was 0.05μg·kg^-·h^-1, followed by second and third step of 1.0 and 1.5μg·kg^-·h^-1 infusion, each step was maintained for 40 min Group P： propofol was administrated in increasing steps to target effect-site concentrations of 1, 2, and 4μg/ml. Group M： midazolam was administrated in continuous increasing step infusion（0. 05, 0.1, 0.2 mg·kg^-1·h^-1 ）. BIS, HR, BP, SpO2 were monitored. Results Compared with the baseline, OAA/S score≤3 three group SBP decreased significantly, OAA/S score≤4 HR decreased （P〈0.05）. Compared with group D, the OAA/S score≤4 in M group, SBP was increased, the OAA/S score≤4 in group P and group M HR significantly increased （P〈0. 05）. Comparison of 5 points and the OAA/S score, OAA/S score≤4 three groups of patients with BIS was significantly lower （P〈 0. 05）. Compared with group D, the OAA/S score 44 in group P and group M BIS decreased （P〈0. 05）. Three groups of patients with BIS were positively correlated with OAA/S score, and the Pk values were more than 0.5 （P〈 0.05）. Conclusion The correlation coefficient between BIS and OAA/S when sedated with dexmedetomidine was implied and BIS can be an effective monitor of the sedation with dexmedetomidine, though less accuracy comparedwith propofol and midazolam.