脑电BIS与听力诱发电位指数AAI用于麻醉恢复期意识监测性能的比较

BIS versus auditory evoked potential index AAI in determination of consciousness after termination of anesthasia with propofol/fentanyl

目的 观察不同芬太尼血浆浓度对麻醉清醒时丙泊酚血浆浓度的影响 ;同时 ,比较脑电双频谱指数 (BIS)和听觉诱发电位指数 (AAI)在此条件下监测意识恢复的性能状态。方法 36例病人 ,以丙泊酚和芬太尼行麻醉诱导和维持。根据麻醉恢复时芬太尼浓度将病人分为两组 :组 1(n =18) >0 7μg/L ,组 2 (n=18)≤0 7μg/L。比较两组病人清醒时丙泊酚浓度、BIS和AAI值等。结果 组 2病人意识恢复时血浆丙泊酚浓度明显高于组 1(P <0 0 5 )。而意识恢复时两组间的BIS值以及AAI值均无显著差异。结论 不同浓度芬太尼可明显影响麻醉清醒所需丙泊酚浓度 ;但BIS和AAI监测值却不随这不同的药物浓度组合的变化而改变 ,提示在一定药物浓度范围内 ,两者均可独立于药物不同浓度比例 ,反映意识抑制程度的变化。

Objective To investigate the effects of different plasma levels of fentanyl on the plasma propofol concentration and to compare effectiveness of BIS and the new AEP index-A-line ARX index (AAI) in determining consciousness regaining after termination of anaesthesia with propofol/fentanyl. Methods Thirty-six patients were anesthetized with propofol/fentanyl. Blood samples were collected for determination of plasma propofol and fentanyl concentrations, BIS and AAI values were recorded at the time when the patients regained consciousness. The patients were divided into two groups according to the fentanyl concentration in plasma on awakening: group 1>0.7μg/L (n=18) and group 2 ≤0.7μg/L (n=18). Propofol concentration, BIS, and AAI were compared between the two groups. Results The patients in group 2 had a significantly higher propofol concentration in plasma (2.70 mg/L) on awakening compared with that of the group 1 (2.08 mg/L) (P<0.05). However, the BIS and AAI values at the recovery endpoint did not differ between the two groups. Conclusions The results suggest that the plasma level of fentanyl has an impact over the concentrations of propofol required for patients to regain consciousness. The BIS and AAI values at the time of regaining consciousness remain unaltered with different combinations of propofol and fentanyl concentrations. Thus, both the BIS and AAI appear useful and are consistent indicators to reflect the degree of inhibition of consciousness when propofol/fentanyl intravenous anesthesia was withdrawn, and they are independent to the proportion of these two drugs.