Canine heart-lung transplantation after twenty-four-hour hypothermic preservation with Belzer-UW solution

Twenty four-hour heart-lung preservation with Belzer-UW solution was studied in the canine heterotopic heart-lung transplant model. Four pairs of mongrel dogs were used. The donor heart was arrested with cardioplegic solution. The heart and the lung were flushed with UW solution, then excised en bloc and immersed in 4 degrees C UW solution for 24 hours. The graft was transplanted heterotopically into the left pneumonectomized recipient. The transplant procedure consisted of end-to-end anastomosis of two left main bronchi, end-to-side anastomosis of the descending aortas, and end-to-end anastomosis of the donor's superior vena cava to the recipient's left pulmonary artery. The recipient's right pulmonary artery was ligated after an observation period, and cardiopulmonary functions were measured during room air ventilation. In all four transplanted dogs the grafts were able to sustain the recipient's circulation. The prepreservation and posttransplant cardiac output was 71.2 +/- 21.6 ml/min/kg and 96.4 +/- 44.4 ml/min/kg; the arterial PO2 was 80.8 +/- 12.9 mm Hg and 74.1 +/- 2.7 mm Hg; and the arterial PCO2 was 25.6 +/- 5.5 mm Hg and 35.9 +/- 13.3 mm Hg, respectively. There were no significant differences between the prepreservation and posttransplant values. Posttransplant myocardial water content was within the normal range. Pulmonary vascular resistance increased significantly, to 13.8 +/- 3.7 from 8.8 +/- 5.2. Wood units, and the wet/dry ratio of the lung increased significantly, to 8.3 +/- 1.6 from 4.4 +/- 0.6. In conclusion, heart-lung grafts preserved in UW solution for 24 hours were able to sustain the recipient's circulation. Significant pulmonary edema, however, could not be prevented.