七氟烷对听觉诱发电位指数的影响

THE INFLUENCE OF SEVOFLURANE ON AUDITORY EVOKED POTENTIAL INDEX

目的观察七氟烷对听觉诱发电位指数(auditory evoked potential index,AEPI,以A-line ARX Inden为代表,即AAI)、脑电双频指数(bispectral index,BIS)、皮质醇(cottisol,Cor)及血流动力学的影响,评价AAI判断七氟烷麻醉深度的可行性。方法选择行腹部手术美国麻醉医师协会体格检查分级Ⅰ～Ⅱ级的患者50例,在咪唑安定、异丙酚、维库溴铵、芬太尼诱导插管后吸入七氟烷,使呼气末浓度分别达0.8%、1.0%、1.2%,并每个浓度维持20 min后以及停吸七氟烷3 min、5 min、拔管时记录AAI、BIS、血压、心率和血清Cor。结果随着呼气末七氟烷浓度的增高,AAI、BIS下降,以上变化与呼气末七氟烷浓度呈线性相关(r=-0.816,-0.813),血压、心率、Cor无显著变化。停吸七氟烷后随着呼气末浓度的下降麻醉减浅AAI、BIS、血压、心率和血清Cor显著升高(P<0.05)。结论七氟烷呼气末浓度在0.8%～1.2%的范围内AAI可作为七氟烷麻醉深度的监测指标。

Objective To observe the influence of sevoflurane on auditory evoked potential index, which is represented by A-line ARX Index（AAI）, bispectral index（BIS）, cortisol（Cor）, and hemodynamics,and to evaluate the feasibility of AAI for predicting the depth of anesthesia by sevoflurane. Methods Fifty cases, American society of anesthesiologists graded Ⅰ～Ⅱ, accepted abdominal operation were anesthetized with midazolam, propofol, vecuronium bromide and fentanyl. After intuhation, sevoflurane was inhaled until the end exhaled concentrations reached the level of 0.8%, 1.0% and 1.2% respectively, and these levels were kept for. 20 min. The parameters of AAI,BIS,blood pressure and heart rate were recorded at the following time points： 20min after inhalation of sevofluane, 3 min and 5 rain after ceased inhalation of sevoflurane, and extubation. And also,the blood samples were taken at these time points for the determination of Cor. Results It showed a linear correlation between the decrease of AAI,BIS and the increase of the end exhaled concentration of sevoflurane, （r=-0.816,-0.813）. But there were no significant changes of blood pressure,heart rate and Cot. After ceased inhalation of sevoflurane, with the decrease of end exhaled concentration, AAI, BIS, heart rate and Cor were significantly increased（ P 〈 0.05）. Conclusion The AAI can be used as an index to assess the depth of anesthesia by inhaling sevoflurane when the end exhaled concentration ranges from 0.8% to 1.2%.