七氟醚预处理对婴幼儿体外循环中氧自由基的影响及意义

Influence and implications of sevoflurance preconditioning on oxygen free radicals in pediatric patients under cardiopulmonary bypass

目的探讨七氟醚预处理对婴幼儿体外循环中氧自由基的影响及意义。方法选择38例须手术治疗的室间隔缺损婴幼儿,随机分为两组(每组19例),S组于气管插管后吸入七氟醚30 min,随后洗脱10 min,使主动脉阻断前七氟醚吸入浓度为0;C组则单纯吸入空—氧混合气体,两组麻醉诱导及维持用药相同。于诱导后、转流前及主动脉开放5、10、30 min抽血测定丙二醛(MDA)浓度及过氧化物歧化酶(SOD)活性,同时测定诱导后及主动脉开放6 h后的CK-MB、cTnI。结果两组患儿诱导后各项指标无统计学差异,主动脉开放6 h后S组CK-MB、cTnI低于C组(P均<0.05);在主动脉开放5、10、30 min时S组SOD活性较C组高,MDA较C组低(P均<0.05);但在转流前S组MDA较C组高(P<0.05)。结论七氟醚预处理过程中通过产生少量氧自由基提前启动机体的抗氧化机制,使体外循环过程中氧自由基的生成减少,最终对缺血—再灌注心肌产生保护作用。

Objective To explore the influence of sevoflurance preconditioning on oxygen free radicals and its implications in pediatric patients under cardiopulmonary bypass （CPB）. Methods Thirty-eight pediatric patients with ventricular septal defect were divided into two groups. Sevoflurance were inhaled for 30 minutes and followed by 10 minutes air-oxy- gen mixture washout in group S after tracheal intubation. Group C inhaled air-oxygen mixture only. Blood samples were obtained for determination of serum concentration of MDA and activity of SOD after induction of anesthesia, before CPB and at 5, 10, 30 minutes after aortic unclamping. The serum concentration of eTnI and activity of CK-MB were detected after induction of anesthesia and at 6 hours after aortic unclamping. Results Compared to the group C, the serum concentration of cTnI and activity of CK-MB were significantly lower at 6 hours after aortic unclamping, the serum concentration of MDA was significantly lower and the serum SOD activity was significantly higher at 5, 10, 30 minutes after aortic unclamping in group S. But the serum concentration of MDA before CPB in group S was significantly higher than that in group C （ P 〈 0.05 ）. Conclusions Sevofluranee preconditioning can inhibit oxygen free radicals during CPB through inducing a few oxygen free radicals at stage of preconditioning. So it can exert protective effects on acute ischemia/reperfusion heart.