성견의 연속 양측 폐이식 실험모델에서 24시간 폐보존 연구

Abstract

Background: Numerous studies on safe, long term preservation for lung transplantation has been performed for the purpose of developing ideal preservation solution with extracellular type or intracellular type solutions and overcoming the shortage of donors. We prepared LPDG (low potassium dextran glucose)solution for lung preservation study. In this study we examined the efficacy of LPDG solution in 24-hour lung preservation by using of a sequential bilateral canine lung allotransplant model. Method: Seven bilateral lung transplant procedures were performed using weight-matched pairs (23 to 26 Kg) of adult mongrel dogs. The donor lungs were flushed with LPDG solution and maintained hyperinflated with 100% oxygen at 10oC for a planned ischemic time of 24 hours for the lung implanted first. After sequential bilateral lung transplantation, dogs were maintained on a ventilator for 3 hours: arterial oxygen tension, pulmonary artery pressure, and pulmonary vascular resistance were determined in the recipients hourly after bilateral reperfusion and compared with pretransplant-recipient values, which used as controls. After 2 hours of reperfusion, the chest X-ray, computed tomogram and lung perfusion scan were performed for assessment of early graft lung function. And pathological examinations for ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery were performed. Results: Five dogs of seven experiments had successfully finished the whole assessments after bilateral reperfusion for three hours. Arterial oxygen tension in the recipients was markedly decreased in immediate reperfusion period but gradually recovered after reperfusion for three hours. The pulmonary artery and pulmonary vascular resistance showed singificant elevation (p＜0.05 versus control values) but also recovered after reperfusion for three hours (p＜0.05 versus immediate period value). The ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery showed reversible mild injury in 24 hours of lung preservation and reperfusion. Conclusions: The present study suggests that LPDG solution provide excellent preservation and transplanted lung function after 24 hours of preservation in a canine model in which the dog is completely dependent on the fuction of transplanted lung.