靶控输注异丙酚时脑电双频谱指数与皮肤电传导监测患者镇静深度准确性的比较

目的 比较靶控输注异丙酚时脑电双频谱指数(BIS)与皮肤电传导(SC)监测患者镇静深度的准确性.方法 拟在硬膜外麻醉下行下肢手术的患者30例,年龄21～56岁,体重52～85 kg,ASA分级Ⅰ或Ⅱ级.异丙酚初始血浆靶浓度0.8 μg/ml,待血浆靶浓度与效应室浓度平衡后.以0.5～0.8 μg/ml血浆靶浓度递增,直至警觉/镇静评分(OAA/S评分)为1分时停止给药,靶控输注异丙酚前记录BIS和SC,作为基础值,异丙酚靶控输注期间记录OAA/S评分、BIS和SC,计算SC变化值(△SC).OAM/S评分与BIS和△SC行Spearman等级相关分析,绘制BIS和△SC判断OAA/S评分及意识消失的受试者工作特征曲线,计算曲线下面积(AUC,分别为AUCBIS和AUC△SC);逻辑回归分析计算BIS和△SC正确判断意识消失的概率.结果 随OAA/S评分的升高,BIS值逐渐升高(P＜0.01),OAA/S评分1分与2分时△SC比较差异无统计学意义(P＞0.05),OAA/S评分3～5分时△SC低于OAA/S评分1分或2分,OAA/S评分3～5分时△SC逐渐降低(P＜0.01),OAA/S评分与BIS呈正相关(r=0.920,P＜0.01),与△SC呈负相关(r=-0.859,P＜0.01);与AUCBIS比较,OAA/S评分5→4分、4→3分时AUC△SC升高,OAA/S评分3→2分、2→1分和意识消失时降低AUC△SC(P＜0.05);BIS与ASC正确判断意识消失的概率分别为93%和82%.结论 靶控输注异丙酚时,患者意识消失前SC监测镇静深度的准确性高于BIS,意识消失后低于BIS;BIS判断患者意识消失的准确性高于SC.

Abstract：

Objective To compare the accuracy of BIS and skin conductance (SC) for assessment of the depth of sedation induced by target-controlled infusion (TCI) of propofol. Methods Thirty ASA Ⅰ orⅡpatients aged 21-56 yr weighing 52-85 kg undergoing orthopedic operation on the lower limb under epidural anesthesia were enrolled in this study.After the onset of epidural anesthesia, TCI of propofol was started at an initial target plasma concentration (Cp) of 0.8 μg/ml. Th Cp was increased by 0.5-0.8 μg/ml every 3 min until OAA/S score=1. OAA/S score, BIS and SC values were recorded, SC change value (△SC) was calculated. Spearman rank-order correlation, receiver operating characteristic curve (area under curve "AUC" was calculated) and logistic regression were used to analyze the relationship of OAA/S score to BIS and △SC.Results BIS and △SC were significantly correlated with OAA/S scores (r were 0.920 and-0.859 respectively). The AUC of △SC (0.919, 0.946) was significantly better correlated with OAA/S score (5→4, 4→3) than that of BIS (0.761, 0.507), while BIS was better correlated (0.781, 0.959) with OAA/S score (3→2, 2→1) than ASC (0.577, 0.630). Logistic regression correctly predicted loss of consciousness. The accuracy of prediction was 93% for BIS and 82% for △SC. Conclusion The accuracy of SC for assessment of the depth of sedation induced by propofol TCI ishigher than that of BIS before loss of consciousness,while lower than that of BIS after loss of consciousness. BIS is more accurate in monitoring the loss of consciousness.

BIS versus skin conductance for assessment of depth of sedation induced by propofol target-controlled infusion

Objective To compare the accuracy of BIS and skin conductance (SC) for assessment of the depth of sedation induced by target-controlled infusion (TCI) of propofol. Methods Thirty ASA Ⅰ orⅡpatients aged 21-56 yr weighing 52-85 kg undergoing orthopedic operation on the lower limb under epidural anesthesia were enrolled in this study.After the onset of epidural anesthesia, TCI of propofol was started at an initial target plasma concentration (Cp) of 0.8 μg/ml. Th Cp was increased by 0.5-0.8 μg/ml every 3 min until OAA/S score=1. OAA/S score, BIS and SC values were recorded, SC change value (△SC) was calculated. Spearman rank-order correlation, receiver operating characteristic curve (area under curve "AUC" was calculated) and logistic regression were used to analyze the relationship of OAA/S score to BIS and △SC.Results BIS and △SC were significantly correlated with OAA/S scores (r were 0.920 and-0.859 respectively). The AUC of △SC (0.919, 0.946) was significantly better correlated with OAA/S score (5→4, 4→3) than that of BIS (0.761, 0.507), while BIS was better correlated (0.781, 0.959) with OAA/S score (3→2, 2→1) than ASC (0.577, 0.630). Logistic regression correctly predicted loss of consciousness. The accuracy of prediction was 93% for BIS and 82% for △SC. Conclusion The accuracy of SC for assessment of the depth of sedation induced by propofol TCI ishigher than that of BIS before loss of consciousness,while lower than that of BIS after loss of consciousness. BIS is more accurate in monitoring the loss of consciousness.