二次主动脉阻断后血浆中LPO、SOD及Vit E的变化

目的研究体外循环心内直视手术中二次阻断主动脉及再灌注后血浆中过氧化脂质（ＬＰＯ）、超氧化物歧化酶（ＳＯＤ）及ＶｉｔＥ含量的变化及其意义。方法６例二次阻断及１４例单次阻断主动脉的病人作为实验组及对照组，测定不同时限血浆中ＬＰＯ、ＳＯＤ及ＶｉｔＥ含量，并进行比较。结果一次阻断再灌注后血浆中均有ＬＰＯ上升及ＳＯＤ、ＶｉｔＥ下降，但两组间无差异。二次阻断及再灌注后血浆中ＬＰＯ进一步升高，ＳＯＤ及ＶｉｔＥ显著降低，术后２ｈ实验组ＬＰＯ显著高于对照组，而ＳＯＤ、ＶｉｔＥ低于对照组。结论体外循环术中再次阻断后将导致更严重的心肌损伤，同时机体抗氧化能力进一步耗竭。

Changes of Lipid Peroxidants,Superoxide Dismutase and Vit E after the Second Aortic Crossclamp during Cardiopulmonary Bypass

bjective To investigate changes of lipid peroxidant,superoxide dismutase and Vit E after the second aortic crossclamp during cardiopulmonary bypass. Method 6 cases with the second aortic crossclamp were collected as experimental group,and another 14 cases with first reperfusion as controls.Plasma lipid peroxidant,superoxide dismutase and vitamin E were tested at different time. Result After the first aortic crossclamp and reperfusion plasma LPO increased and SOD,Vit E decreased in both groups without significant difference.After the second crossclamp and second reperfusion LPO increase rapidly and SOD,Vit E were significantly lower than preoperation values.LPO,SOD and Vit E had significant difference between two groups at postoperative 2 h. Conclusion After recrossclamping during cardiopulmonary bypass,serious oxygen radicals-mediated myocardial injury occured with plasma antioxidant depletion.