瑞芬太尼预处理对冠状动脉旁路移植术患者体外循环期间的脑保护作用

目的 探讨瑞芬太尼预处理对冠状动脉旁路移植术患者体外循环期间的脑保护作用.方法 择期行体外循环(CPB)冠状动脉旁路移植术的患者40例,ASA Ⅱ或Ⅲ级,随机分为4组(n=10):对照组(C组)和不同剂量瑞芬太尼预处理组(R_(1～3)组).R_(1～3)组于麻醉诱导后30 min时分别静脉输注瑞芬太尼0.6、1.2和1.8 μg·kg~(-1)min~(-1),输注时间5 min,重复3次,间隔5 min;C组以生理盐水代替瑞芬太尼.于麻醉诱导前(T_0)、CPB开始前(T_1)、CPB 30 min(T_2)、CPB结束(T_3)时取颈内静脉血样3 ml,采用ELISA法测定血浆S-100β蛋白浓度,采用比色法测定血浆超氧化物歧化酶(SOD)活性和丙二醛(MDA)浓度.结果 与T_0时比较,T_(1～3)时各组血浆S-100β蛋白和MDA浓度升高,SOD活性降低(P<0.05或0.01);与C组比较,R_3组T_(2,3)时血浆S-100β蛋折和MDA浓度降低,SOD活性升高(P<0.05),R_1组和R_2组上述指标差异无统计学意义(P>0.05).结论 瑞芬太尼(1.8μg·kg~(-1)min~(-1))预处理可减轻冠状动脉旁路移植术患者CPB诱发脑损伤,其机制可能与抑制脑脂质过氧化反应有关.

Cerebral protective effect of remifentanil preconditioning during cardiopulmonary bypass in patients undergoing coronary artery bypass grafting

Objective To investigate the cerebral protective effect of remifentanil preconditioning during cardiopulmonary bypass in patients undergoing coronary artery bypass grafting (CABG). Methods Forty ASA Ⅱ or Ⅲ patients of both sexes aged 55-64 yr weighing 50-85 kg undergoing elective CABG were randomized into 4 groups (n = 10 each) : control group (group C) and remifentanil groups (group R_1, R_2, R_3). Anasthesia was induced with midazolam 0.04 mg/kg, remifentanil 1 μg/kg, propofol 1 mg/kg and pipecuronium 0.1 mg/kg and maintained with isoflurane inhalation,intravenous continuous propofol infusion at 6-10 mg·kg~(-1)·h~(-1) and intermittent iv boluses of sufentanil and pipecurpnium after tracheal intubation. The patients were mechanically ventilated. P_(ET) CO_2 was maintained at 35-45 mm Hg. A catheter was inserted into internal jugular vein and advanced cranially until jugular bulb for blood sampling. The remifentanil groups received three 5 min episodes of iv remifentanil infusion at 0.6 μg/kg~(-1) ·min(-1) (group R_1),1.2μg/kg~(-1) ·min(-1)(group R_2) and 1.8μg/kg~(-1) ·min(-1)(group R_3) at 5 min intervals after induction of anesthesia before operation.Blood samples were obtained from jugular bulb before induction of anesthesia (T_0, baseline), before CPB (T_1), 30 min after initiation of CPB (T_2) and at the end of CPB (T_3) for determination of plasma S-100βprotein and MDA concentrations arid SOD activity. Results Plasma S-100β protein and MDA concentrations were significantly increased while plasma SOD activity was significantly decreased at T<1-3> as compared with the baseline values at T_0 in all 4 groups. Plasma S-100β protein and MDA concentrations were significantly lower while plasma SOD activity was significantly higher at T_2 and T_3 in group R_3 than in the other 3 groups. Conclusion Preconditioning with larger doses of remifentanil (1.8 μg/kg~(-1) ·min(-1)) can attenuate brain injury induced by CPB in patient undergoing CABG through inhibiting oxidative stress response.