地氟醚对听觉诱发电位指数和数量化脑电图的影响

目的：观察地氟醚对听觉诱发电位指数（AAI）、数量化脑电图（QEEG）各参数和血流动力学的影响，评价AAI判断地氟醚麻醉深度的可行性。方法：选择行下腹部手术ASAⅠ～Ⅱ级的病人30例，在异丙酚、维库溴铵诱导插管后分别吸入0.8，1.0，1.3 MAC的地氟醚，每个浓度维持20 min。记录血压，心率，AAI（A-line ARX index），BIS（bispectral index），SEF（95% spectral edge frequency）和MF（midian frequency）的值。结果：随呼吸末地氟醚浓度的增高，AAI，BIS，95%SEF和MF均显著降低，以上改变与呼吸末地氟醚浓度呈线性相关关系（r分别为0.830，0.930，0.803，0.885，P<0.01）。MAP和HR却无明显变化，HR在地氟醚浓度为1.3 MAC时比1.0 MAC时要显著增快。结论：地氟醚浓度在0.8~1.3 MAC的范围内，AAI，BIS，95%SEF和MF都可作为地氟醚麻醉深度的监测指标。而MAP和HR不能反映地氟醚的麻醉深度。

Effects of desflurane on auditory evoked potential index and quantitative electroencephalogram

OBJECTIVE: To observe the effects of desflurane on A-line ARX Index (AAI), QEEG, MAP and HR, and to investigate the feasibility of AAI, QEEG, MAP and HR in monitoring the depth of anesthesia with desflurane. METHODS: Thirty patients classified as ASA physical status I approximately II were scheduled for elective lower abdominal surgery. Anesthesia was induced with propofol and vecuronum. After the tracheal intubation, the lungs were ventilated with desflurane in oxygen. End-tidal desflurane concentrations were maintained at 0.8, 1.0 and 1.3 MAC for 20 minutes, respectively. The parameters of record included AAI, BIS (bispectral index), SEF (95% spectral edge freqency), MF (midian freqency), MAP and HR. RESULTS: AAI, BIS, SEF and MF significantly decreased in a linear manner (r = 0.830, 0.930, 0.803, and 0.885, respectively, P < 0.01) with increasing end-tidal concentration of desflurane range of 0.8 approximately 1.3 MAC. MAP and HR did not change much. HR increased significantly at concentration 1.3 MAC than that of 1.0 MAC. CONCLUSION: Within end-tidal desflurane concentration range 0.8 approximately 1.3 MAC, both AAI and parameters derived from EEG (such as BIS, SEF, MF) can serve as parameters in monitoring the depth of anesthsia with desflurane, while MAP and HR can not.