The Research On Injury Of Lungs Post CPB And The Intervention Effect Of Ligustrazin In Infant Congenital Heart Disease

Objective:(1)Through measuring the variation of the proinflammatory cytokines (TNF-α,IL-6,IL-8), neutrophils, respiratory index (RI), oxygen index (OI), static lung compliance (Cstat) and the histologic change before and after the cardiopulmonary bypass (CPB), to investigate the effect of CPB exerting to the lungs. (2) Pretreated with ligustrzine before the CPB, to study the effect of ligustrazine preventing the injury of lungs post CPB through measuring the above index, and investigate the probable mechanism.Methods: (1) 40 patients post CPB were randomized into two study groups, the treated group and the control group. (2) The treated group patients were given with ligustrazine (5mg/Kg) intravenously at 1 hour before the CPB, and the control patients were given with the same dosage saline. (3) By using the ELISA, measure the plasma concentration of the proinflammatory cytokines such as IL-6,IL-8,TNF-αand Ne at the time point of T₁ (10 min after the trachea cannula), T₂ (5 min after bypass), T₃ ( time of the surgery termination), T₄ (2 hours after the surgery) and T₅ (24 hours after the surgery). (4) Test pulmonary function (RI, OI, Cstat) at the time of T₁, T₃ and T₄. (5) Analyze the histologic change of the lungs using the light microscope and the electrical microscope before and after the surgery.Result: (1) Proinflammatory cytokines and the neutrophils: TNF-αhas only been found at T₃ and T₄ of the 5 control and 2 treated patients; the concentration of IL-6 and IL-8 had increased significantly (p<0.05), the control group was more significant (p<0.05), then decreased to the normal level at T₅, but IL-6 concentration was a little higher than treated group; the neutrophil quantity increased after CPB, but the difference was not significant between the two groups. (2) Pulmonary function parameters: before and after CPB, static lung compliance of the two group patients decreased (p<0.05), and more obvious in the control group (p<0.05); RI of the two group patients increased significantly(p<0.05), and more obvious in the control group; OI of the control group patients decreased significantly (p<0.01), and no statistically significant in the treated group patients. (3) Relativity of the proinflammatory cytokines, neutrophils and Pulmonary function parameters:these factors are correlative, IL-8, Ne and RI were positively straight-line correlation with each other (r=0.585, p<0.05;r=0.458, p<0.01); IL-6,IL-8 and Ne were negatively straight-line correlation with OI respectively (r=-0.528, p<0.05; r=-0.697, p<0.01; r=-0.429, p<0.01); IL-8 was negatively straight-line correlation with Cstat (r=-0.413, p<0.01). (4) Through the light microscope, gentle congestion was observed in the lung tissue of the both group samples after the surgery, although the ratio of area of parenchyma versus the total slide of the lungs was not significantly different, but there exist the breakdown of alveolus structure and atelectasis in the control samples; through observing by electrical microscope,the villus of type II alveolar epithelial cells in the control samples were diminished, intra-cellula chondrosomes swallowed obviously, threre existed the exudation in the alveolar space. There was no significant change except for light swelling in the type I alveolar epithelia cells.Conclusion: (1) Pulmonary function could be damaged by the CPB procedure in the surgery for CHD, the principle changes included the Cstat and OI were diminished, proinflammatory cytokines of IL-6 and IL-8 increased, the number of the neutrophils increased, furthermore,these were correlation with pulmonary function parameters; through observing the lung tissues in LM and EM before and after the surgery, there existed the breakdown of alveolar epithelial cells, alteration of the lung mesenchymal and vasopermeability change of the lung vessels. These demonstrated the CPB could harm the pulmonary function after the surgery of CHD. (2) Application of the ligustrazine before the CPB may reduced the peak level of IL-6 and IL-8 after the CPB, then improved the pulmonary function parameters (Cstat, RI, OI ), alleviate the destruction of ultrastructure of the lung tissues and protect the pulmonary function.