Functional evaluation of the transplanted lung after long-term preservation.

In dogs the immediate value of transplanted lungs was tested after preservation in Collins 3 solution and administration of aprotinin. 15 animals received a left or right homograft, which had been preserved for 24 h. In 3 cases preservation time was prolonged to 48 h, and in another 2 dogs both of the lungs were replaced by 24-hour preserved organs in a one-stage operation. The value of the transplants was tested by several physiological, morphological and clinical phenomena. (1) A positive O2 uptake of the transplant after a temporary occlusion of the opposite pulmonary artery documented its capacity for gaseous exchange. (2) Scintigraphic visualization of perfusion and ventilation in 3 dogs demonstrated satisfactory results. (3) A positive response to acetylcholine of the bronchial muscular system was observed in all transplants. (4) Normal light microscopy showed a lack of obvious morphological change. (5) Only slight alterations in electron microscopy were found when compared to those found before preservation. (6) The absence of acute bronchial edema excludes the possibility of irreversible altertions of the alveolocapillary wall. The results demonstrate that preservation of the lung is possible up to a period of 48 h.