Autologous lung as oxygenator in cardiopulmonary bypass

Objective To study whether autologous lung as oxygenator in cardiopulmonary bypass is better than the conventional cardiopulmonary bypass with artificial oxygenator in pulmonary preservation. Methods 12 piglets were randomly divided into two groups with six each. The experimental group underwent bi-ventricular bypass with autologous lung perfusion. While control group underwent conventional cardiopulmonary bypass with artificial oxygenator. The bypass time and aortic cross clamping time were 135 min and 60 min respectively for each animal. The lung static compliance (Cstat), the alveolus-artery oxygen difference (PA-aO_2), the TNF-α, IL-6 and wet to dry lung weight ratio (W/D) were measured. Histological and ultra-structural changes of the lung were also observed after bypass. Results After cardiopulmonary bypass, the Cstat decreased, the PA-aO_2 increased and the content of TNF-α increased for both groups, but the changes of experimental group were much less than those of control group. Lower W/D ratio and milder pathophysiological changes in experimental group were also demonstrated. Conclusion Autologous lung can tolerate nonpulsatile perfusion. It can be used as oxygenator in cardiopulmonary bypass to substitute the artificial oxygenator. By this method, the inflammatory lung injury after cardiopulmonary bypass caused by ischemia reperfusion and using non-physiological artificial oxygenator could be lessened.