Pulmonary Artery Perfusion With Hypothermic Solution Inhibits The Apoptosis Of Lung Parenchymal Cell During Cardiopulmonary Bypass

Objective:To study the effect of pulmonary artery perfusion with hypothermic solution on the apoptosis of lung parenchymal cells during cardiopulmonary bypass. Methods:Twenty cases undergoing mitral valve replacement (MVR) were randomly divided into lung protective group (n=10) and control group(n=10). Hypothermic protective solution was infused to the main pulmonary artery in the protective group, and Sodium Chloride was infused to the main pulmonary artery in the control group. Lung biopsy specimens were obtained at before and after cardiopulmonary bypass in order to study the apoptosis of lung parenchymal cells using tunnel techniques and the apoptosis of lung parenchymal cells histological changes. At same time, Patients'lung functions were monitored.Results:The oxygenation index was higher in the lung protect group than that in the control group at 0h, 6h, 12h and 24h after CPB (t=6.880, P< 0.01;t=3.757,P<0.01;t=3.682, P<0.01;t=2.416, P <0.05 respectively).The sitau Tunnel staining showed that after CPB ,the number of apoptosis cell in lung protective group and control group increased significantly ,compared with those of before CPB(P<0.01).After CPB,The rate of apoptosis cells of lung parenchymal cells was (18.68±1.34)% in control group,whereas the lower rate (10.46±1.96)% was showed in protective group.There was significant difference between both groups(P<0.01). Conclusions(:1)Conventional hypothermic CPB induces apoptosis in lung parenchy- mal cells.(2)Pulmonary artery perfusion with hypothermic solution can inhibit the apoptosis of lung parenchymal cells and relieve lung injury induced by CPB,Which showed the effects of lung protection in our solution.