University of Wisconsin solution extends lung preservation after prostaglandin E1 infusion

University of Wisconsin (UW) solution has been demonstrated to enhance and extend the preservation of the hepatic, pancreatic, renal, and cardiac allografts. Prostaglandin E1 (PGE1), which has been used to produce pulmonary vasodilatation, has improved preservation in lung transplantation. Experiments were designed to evaluate their potential role in 24-h preservation of the allografts in lung transplantation. Thirty-six dogs underwent left lung transplantation. The donor lungs (n = 6 in each group) were flushed with UW solution (group 1 and 2) or modified Euro-Collins (EC) solution (group 3) after PGE1 infusion (500 micrograms). In group 1, donor lungs were transplanted immediately. Lung allografts of group 2 and 3 were cold stored (4 degrees C) in the same preservation solution for 24 h in the inflated state and then transplanted. The right pulmonary artery and right main bronchus were ligated 1 h after completion of the transplantation, forcing the recipient dogs to survive with the transplanted left lung. The recipients were ventilated with an inspired oxygen fraction of 0.4 and end-expiratory pressure 10 cm H2O. Two dogs died prematurely in group 3, whereas all dogs in group 1 and 2 survived the experimental period. The arterial oxygen tension and saturation and dynamic lung compliance were significantly higher in dogs of group 1 and 2. Transplanted lungs of group 1 and 2 had significantly lower pulmonary vascular resistance, alveolar-arterial oxygen difference, and wet/dry lung weight ratio. Histologically, pulmonary edema, congestion, sloughing of bronchial mucosa, and peribronchial and peripulmonary arterial hemorrhage were shown in lungs of group 3, but not in those of group 1 and 2. Airway mucosa and pulmonary vascular structure were well preserved in lungs of group 1 and 2. There was no significant difference between group 1 and 2 in lung functions, hemodynamics, or morphologic features. We concluded that PGE1 and UW solution could effectively extend lung preservation up to 24 h in this in vivo canine lung allotransplantation model.