靶控输注异丙酚诱发患者脑电图爆发性抑制所需的靶浓度

The target plasma concentration of propofol required to induce burst suppression with target-controlled infusion

目的确定靶控输注（TCI）异丙酚诱发脑电图爆发性抑制所需的血浆靶浓度，以用于围术期脑保护。方法150例全麻手术患者，性别不限，年龄18～55岁，体重指数〈30；无心肺肝肾疾患，排除可能影响脑电活动的干扰因素。靶控输注异丙酚行全麻诱导，初始血浆靶浓度设定为5．4μg／ml。连续实时监测患者的脑电图波形和爆发性抑制比率，靶浓度从5．4μg／ml开始，以0．3μg／ml为梯度逐渐上升，每一靶浓度维持15min，直至出现爆发性抑制，记录此时的血浆靶浓度。结果靶控输注异丙酚诱发脑电图爆发性抑制所需的血浆靶浓度平均为（6．1±0．6）μg／ml，95％可信区间5．99～6．19μg／ml，男性与女性之间的差异无统计学意义。结论将异丙酚血浆靶浓度提高至6．2μg／ml可诱发出脑电图爆发性抑制，有利于术中脑保护。

Objective To determine the optimal target plasma concentration of propofol required to induce EEG burst suppression administered by TCI in order to decrease cerebral metabolic rate and increase tolerance to cerebral ischemia and hypoxia. Methods One hundred and fifty ASA Ⅰ - Ⅱ patients（aged 18- 55 years old, BMI 〈 30, Mallampati Score Ⅰ -Ⅱ ） scheduled for elective surgery undergoing general anesthesia were enrolled in this study. Patients with systemic diseases or other factors effecting the electrical activity of brain were excluded. ECG, IBP, SpO2, PetCO2, Temperature and EEG（ two-channel referential montage system） were continuously monitored during the procedure. Patients were induced with TCI propofol （the target plasma concentration was initially set at 5.4 μg/ml）, After induction and intubation, target plasma concentration was increased by 0. 3 μg/ml increment and sustained 15 minutes until EEG burst suppression appeared（ stable burst suppression waveform and BSR 〉 50% ）, and this target concentration was recorded. Results The mean target plasma concentration of propofol with TCI required to induce EEG burst suppression was 6. 1 ± 0. 6 μg/ml with 95% confidence interval of 5.99-6. 19 μg/ml. There was no significant difference between the genders. Conclusions The target plasma concentration of propofol reached 6. 2 μg/ml can induce EEG burst suppression, which is better for intraoperative cerebral protection.