脑电双频指数在重症患者不同药物镇静深度监测中的对比

目的：比较脑电双频指数监测右美托咪定及丙泊酚镇静深度的准确性。方法需要机械通气的重症患者40例，随机分为右美托咪定组（D组）和丙泊酚组（P组），各20例。右美托咪定组（D 组）给予负荷剂量1μg/kg，维持剂量0.2～0.7μg·kg-1·min-1。丙泊酚组（P组）给予负荷剂量1～3mg/kg，维持剂量0.5～4.0mg·kg-1·min-1镇静。机械通气后24h内，两组患者均每2h记录一次BIS值，随后立即进行RASS评分；同时记录两组患者镇静前后的心率（HR）、呼吸频率（RR）、平均动脉压（MAP）、经皮血氧饱和度（SpO2）。以RASS评分＜-3分为标准绘制受试者工作特征曲线（ROC 曲线），确定两组药物镇静适度时所对应的最适BIS 值。结果两组患者BIS与RASS评分均具有较好相关性,其中右美托咪定组的相关性较丙泊酚组差。右美托咪定组患者的最佳BIS截断值为58.5，灵敏度、特异度分别为0.929、0.872；丙泊酚组患者的最佳BIS截断值为63.5，灵敏度、特异度分别为0.987、0.875。两组患者镇静后的生命体征均较镇静前平稳。结论 BIS 可用于监测右美托咪定的镇静深度，但准确性较其监测丙泊酚的镇静深度差，在相同等级的RASS评分下，应用右美托咪定镇静的BIS值偏低。

The contrast of different drug sedation monitoring of bispectral index in severe patients

Objective To compare the accuracy of the application of bispectral index （BIS） on dexmedetomidin and propofol in monitoring sedation depth. Methods 40 patients needing mechanical ventilation in ICU were selected in the study. The patients were randomly divided into two groups： group D（n=20）：dexmedetomidine group; group P（n=20）： propofol group. Group D：the loading dose of dexmedetomidine was 1μg/kg,and the maintained dose was 0.2~0.7μg·kg-1·min-1. Group P： the loading dose of propofol was 1~3mg/kg,and the maintained dose was 0.5~4.0mg·kg-1·min-1. Mechanical ventilation in 24 hours, the BIS of each patient was measured every 2 hours and RASS was scored at once. Meanwhile, heart rate（HR）, respiration rate （RR）, mean arterial pressure（MAP） and saturation of peripheral oxygen（SpO2） was monitored respectively. Receiver operating characteristic （ROC） curve was drawn with the standard whose RASS was lower than-3 point in order to determine the optimal BIS value when adequate sedation level were achieved in the two groups respectively. Results The BIS and RASS of the two groups had positive correlation, but dexmedetomidine group was poorer than that in propofol group. The optimal cutoff BIS value was 58.5（sensitivity was 0.929, specificity was 0.872）for dexmedetomidin and 63.5（sensitivity was 0.987,specificity was 0.875） for propofol. The vital signs in two groups were more stable after sedation than before. Conclusion BIS could be an effective monitor of the sedation with dexmedetomidin, but less accurate than propofol. The BIS value with dexmedetomidin is lower than with propofol at the same level of RASS.