A no-flush, core-cooling technique for successful cardiopulmonary preservation in heart-lung transplantation

In order to determine whether a no-flush, core-cooling technique could provide extended heart-lung preservation, we placed donor calves on cardiopulmonary bypass and instituted rapid cooling to 15 degrees C during the continuous infusion of isoproterenol. The heart and lungs were harvested after the administration of a cardioplegic solution through the aortic root. In the control group (N = 5), heart and lungs were orthotopically allotransplanted immediately. In the preserved group (N = 5), heart and lungs were similarly excised but were stored in a normal saline bath at 4 degrees C for approximately 4 hours and then transplanted. Both groups received isoproterenol during reperfusion and were studied for 6 hours after implantation. A load independent analysis of myocardial function was done by determining with a sonomicrometer the ratio of the end-systolic pressure to the end-systolic dimension. Pulmonary preservation was evaluated by measurement of extravascular lung water with a double-indicator dilution method, arterial oxygenation on 100% inspired oxygen, and serial lung biopsies. Myocardial and pulmonary function after 4 hours of static preservation was found to be similar to controls. No-flush, core-cooling with cardiopulmonary bypass provides adequate cardiorespiratory function after acute bovine heart-lung allotransplantation. With the use of this technique, successful extended cold ischemic cardiopulmonary preservation for heart-lung transplantation may be achieved.