Protective Effects Of Pulmonary Artery Perfusion And Intermittent Ventilation On Lung During Cardiopulmonary Bypass

Objective: To explore the protective effects of comprehensive measures,including pulmonary artery perfusion with 4℃oxygenated blood and intermittent ventilation on lung during cardiopulmonary bypass(CPB).Methods: Thirty patients with rheumatic heart disease (RHD) or congenital heart defect (CHD) were divided into two groups with random number table: protective group (n=15) , given simultaneously intermittent ventilation and pulmonary artery perfusion with 4℃oxygenated blood on lung during CPB; control group (n =15) , performed using routine approaches. Mechanical ventilation time was recorded , the lung oxygenate index (OI),respiratory index (RI),airway resistance(Raw) and lung static compliance (Cstat ) were detected in the beginning and ending time of CPB ,1 hour and 6 hours after CPB termination, respectively. Lung biopsy specimens were obtained after operations in order to study the apoptosis of lung parenchymal cells using tunnel techniques and to were used to observe the morphological changes of lung tissue with light and electronic microscopes.Results: The time of mechanical ventilation was significantly shorter in protective group than in control group .the OI and Cstat of protective group at 1 hour and 6 hours after CPB termination was significantly better than that of the control group (P < 0.05,P < 0.01) ;The Raw and RI of protective group was significantly lower than that of control group at1 h and 6 h (P<0.05, P< 0.01) . And the pathological changes of lung tissue were significantly improved in the treatment group, the rate of apoptosis cells of lung parenchymal cells was (16±5)% in control group ,whereas (9±2) % in protective group, There was significant difference between both groups (P< 0.05) .Conclusion: Comprehensive measures,pulmonary artery perfusion with 4℃oxygenated blood and intermittent ventilation, has protective effects on lung injury during CPB.