地氟醚和异氟醚对脑电图的影响

目的　比较相同MAC浓度的地氟醚和异氟醚对脑电图的影响。方法　选择 2 0例 2 0～ 5 0岁 ,ASAⅠ～Ⅱ级择期手术的病人 ,均不用术前药。麻醉诱导以静脉异丙酚 2mg/kg ,琥珀胆碱 2mg/kg快速气管插管 ,单纯吸入地氟醚或异氟醚维持麻醉。控制呼吸 ,维持呼气末二氧化碳分压 (PetCO2 )在 4 .7～ 6.0kPa。以TOF监测肌松 ,维持T4 /T1<2 5 %。以双导联方式监测脑电变化 ,观察呼气末麻醉药浓度在 0 .5、0 .8、1.0、1.3和 1.5MAC时的脑电边缘频率 (SEF)和双谱指数 (BIS)的改变。结果　随MAC的增加SEF和BIS逐渐减小 ,呈负性线性相关关系 (r分别为 - 0 .95和 - 0 .99,P <0 .0 1) ,2组间SEF和BIS无显著性差异 (P >0 .0 5 )。结论　地氟醚对脑电图的影响与异氟醚相似 ;EEG对监测麻醉深度有一定指导意义

Effects of Desflurane and Isoflurane on EEG

Objective To compare the effects of desflurane and isoflurane on EEG. Methods 20 ASA grade Ⅰ～Ⅱ, aged 20～50 year-old, unpremedicated adults patients undergoing elective surgery were randomly divided into two groups: desflurane (n=10) and isoflurane group (n=10). Anesthesia was induced with propofol 2mg/kg and succinylcholine 2mg/kg intravenously and maintained with inhalation anesthetics. After incubation patients were ventilated mechanically to maintain PetCO 2 between 4.7 and 6.0kPa. The TOF ratio of T4/T1 was maintained less than 25% throughout anesthesia. Two channels EEG monitor was applied. End-tidal concentration was adjusted at 0.5, 0.8, 1.0, 1.3 and 1.5 MAC in sequence was maintained for 10 min before SEF and BIS were recorded. Results There were negative remarkable correlation between either SEFor BIS and MAC in both groups (r=-0.95 and -0.99, P<0.01) There was no significant difference between two groups in EEG. Conclusion The EEG may be useful in evaluating anesthesia depth. The effects of desflurane and isoflurane on EEG were similar at equivalent effective concentration.