改良超滤联合平衡超滤对婴幼儿体外循环术后MDA、TXA_2、LT血浆含量和肺功能影响

Effects of Balanced Ultrafiltration Combined with Modified Ultrafiltration Technique on Plasma Levels of MDA、TXA_2、LT and Pulmonary Function in Infant Open Heart Surgery

目的:探讨婴幼儿体外循环术后肺损害机理及平衡超滤联合改良超滤对其肺功能保护效果。方法:将60例先天性心脏病患儿随机分为对照组(C)、改良超滤组(M)和平衡超滤联合改良超滤组(U)。M组在转流结束后应用改良超滤,U组在转流开始后进行平衡超滤,转流结束后进行改良超滤。分别在转流前(T1)、转流结束后20min(T2)、术后2h(T3)、术后6h(T4)、术后12h(T5)和术后24h(T6)测定记录气道峰压(Ppeak)、呼吸停顿压(Ppause)、潮气量(TV)、呼吸频率(F)、吸入氧浓度(FiO2)和吸气比例(insp%)并测量动脉血中丙二醛(MDA)、血栓素花生四烯酸(TXA2)、白三烯(LT)的浓度。结果:各组体外循环术后较术前的肺静态顺应性(Cstat)、氧合指数(OI)降低,肺泡-动脉氧分压(AaDO2)增加,在T3、T4时间U和M组的Cstat、OI高于C组;AaDO2低于C组。C组MDA、TXA2、LT术后浓度均较术前升高,在T3、T4、T5时间高于U和M组。结论:术后肺功能损害可能与CPB后花生四烯酸代谢产物之间浓度失衡导致肺毛细血管内皮损伤有关。联合应用平衡超滤和改良超滤可降低血浆中MDA、TXA2、LT的浓度,调节花生四烯酸各代谢产物之间浓度失衡,减轻炎性反应,改善患儿肺脏的通气功能和换气功能,具有良好肺保护作用。

Objective：To study the mechanism of pulmonary injury and the effect of balanced ultrafiltration with modified ultrafiltration on pulmonary function in infant open heart surgery.Methods：60 cases of congenital heart disease were divided into contro1 group（C）,modified ultrafiltration group（M）and balanced ultrafiltration with modified ultrafihration group（U）.The cardiopulmonary bypass（CPB）was used with modified ultrafiltration in Group M and balanced ultrafiltration with modified ultrafiltration in group U.The pneumodynamic parameters and MDA、TXA2、LT were measured at specific time points.Results：The static pulmonary compliance（Cstat）and oxygen index（OI）were lower,and alveolar-arteria oxygen difference（AaDO2）was higher after CPB in the three groups.At T4 and T5 time points,the Cstat and OI in group U and M was higher than that in the group C,AaDO2 in group U and M was lower than that in the group C.The 1evels of MDA、TXA2、LT were higher after CPB in the C group.At T4 and T5 time points,the MDA、TXA2、LT in group C was higher than that in the groups U and M.Conclusion：The pulmonary injury in pediatric open heart surgery may be concerned with the endothelial damage of pulmonary capillaries due to disequilibrium of arachidonic acid metabolites.Therefore,combined balanced ultrafiltration with modified ultrafiltration degrades plasma concentrations of MDA、TXA2、and LT,rectificats disequilibrium of arachidonic acid metabolites and improves pulmonary ventilation and air exchange function.