中低温体外循环对婴幼儿先天性心脏病术后的肺损伤

Lung Injury after Moderate Hypothermy Cardiopulmonary Bypass in Infants with Congenital Heart Disease

目的探讨中低温体外循环(CPB)对婴幼儿先天性心脏病(CHD)术后的肺损伤。方法选择本院经CPB行CHD手术的患儿40例,分别在气管插管后10 min(T1)、转流后5 min(T2)、手术结束时(T3)、术后2 h(T4)、术后24 h(T5)采集动脉血3 mL,离心取血浆,通过酶联免疫吸附法(ELISA)检测CHD患儿血浆炎细胞因子IL-6、IL-8水平,在T1、T3、T4测定肺功能参数:肺静态顺应性(Cstat)、氧合指数(OI)、呼吸指数(RI)。CPB前后取其肺组织,光镜、电镜下观察其结构变化。结果与术前测定值比较,CPB后IL-6、IL-8、RI均显著升高(Pa<0.05),Cstat、OI均显著降低(Pa<0.01),且致炎细胞因子与肺功能参数变化存在相关性:IL-8与RI呈正相关(r=0.585 P<0.05),与Cstat、OI均呈负相关(t=-0.413,-0.697 Pa<0.01);IL-6与OI呈负相关(r=-0.528 P<0.05),手术前后在光电镜下观察肺组织有明显病理改变:光镜下肺泡壁、毛细血管轻度充血,肺泡破坏及肺局部不张。电镜下Ⅰ型肺泡上皮细胞破坏,Ⅱ型肺泡上皮细胞绒毛减少,细胞内线粒体肿胀,肺泡腔内渗出,肺间隔水肿。结论中低温CPB能明显引起婴幼儿CHD术后肺损伤,并可能与IL-6、IL-8的变化相关。

Objective To explore the lung injury after moderate hypothermy cardiopulmonary bypass（CPB） in infants with congenital heart disease （CHD）. Methods Forty infants with CHD, by using the ELISA,were detected for the plasma concentration of the proinflammatory eytokines such as IL-6,IL-8 at the time points of T1 （10min after the trachea eannula） ,T2 （5 min after bypass）,T3 （time of surgery termination） ,T4 （2 hours after surgery） and T5 （24 hours after surgery）. Pulmonary fimetion was examined[ respiratory index（RI） ,oxygen index （OI） , static lung compliance （Cstat） ] at the time points of T1 , T3 and T4. The histological changes of the lungs were analyzed by using the light microscope and the electrical microscope before and after CPB. Results After CPB, IL -6, IL -8 and RI increased significantly （Pa 〈 0. 05） ,Cstat and Ol decreased signifieantly（P 〈0.01 ） ,IL -8 had positive correlation with RI（r =0. 585 P 〈0.05） ,and negative correlation with Cstat and OI（r = -0. 413, -0. 697 P 〈0.01 ）. IL -6 had negative correlation with OI（r = -0. 528 P 〈0.05）. There were obvious pathological changes in the lung tissue before and after CPB. Under light microscope, the alveolar wall and capillaries had hyperaemia slightly,and the alveoli of lung were destroyed, the lung did not open partially, through observing by electrical microscope, the type Ⅰ alveolar epithelia cells were damaged ,the villi of type Ⅱ alveolar epithelial cells in the control samples diminished ,intra - eellula chondrosomes swallowed obviously,there existed the exudation in the alveolar space. Conclusions Moderate hypothermy CPB can cause lung injury in infants with CHD,which may be correlated with IL-6 and IL- 8 after CPB.