Continuous infusion of nitroglycerin improves pulmonary graft function of non-heart-beating donor lungs.

Background: The warm ischemic period of lungs harvested from a non-heart-beating donor (NHBD) results in an increased ischemia-reperfusion injury after transplantation. The intravenous application of nitroglycerin (NTG), a nitric oxide (NO) donor, proved to be beneficial during reperfusion of lung grafts from heart-beating donors. The objective of the present study was to investigate the effect of nitroglycerin on ischemia-reperfusion injury after transplantation of long-term preserved NHBD-lungs.

Methods: Sixteen pigs (body weight, 20-30 kg) underwent left lung transplantation. In the control group (n=5), lungs were flushed (Perfadex, 60 mL/kg) and harvested immediately after cardiac arrest. In the NHBD group (n=5) and the NHBD-NTG group (n=6), lungs were flushed 90 min (warm ischemia) after cardiac arrest. After a total ischemia time of 19 hr, lungs were reperfused and graft function was observed for 5 hr. Recipient animals in the NHBD-NTG group received 2 microg/kg/min of NTG administered intravenously during the observation period starting 5 min before reperfusion. Tissue specimens and bronchoalveolar lavage fluid (BALF) were obtained at the end of the observation period.

Results: Compared with the control group, pulmonary gas exchange was significantly impaired in the NHBD group, whereas graft function in the NHBD-NTG group did not change. Leukocyte fraction and protein concentration in the BALF and histologic alteration of the NHBD-NTG group were not different from controls.

Conclusions: Continuous infusion of NTG in the early reperfusion period improves pulmonary graft function of NHBD lungs after long-term preservation. The administration of an NO donor during reperfusion may favor the use of NHBD lungs to alleviate the critical organ shortage in lung transplantation.