IMPAIRED BRONCHIAL HEALING AFTER LUNG DONATION FROM NON-HEART-BEATINGDONORS

Background: Bronchial viability after lung transplantation remains a c oncern. Modern preservation methods, surgical technique, and limited c old ischemic periods have decreased the frequency of bronchial complic ations. However, lungs procured from non-heart-beating donors are subj ected to a mandatory period of warm ischemia. We investigated bronchia l healing in a porcine survival model of left lung transplantation usi ng organ procurement from non-heart-beating donors after a 60-minute p eriod of warm ischemia. Methods: Fourteen adult domestic swine underwe nt left lung transplantation. All lungs were preserved with cold Euro- Collins flush and stored inflated at 4 degrees C. Control lungs (n = 5 ) were flushed, harvested, and stored for 2 hours before implantation. Experimental lungs (n = 9) were procured from non-heart-beating donor s. These lungs were subjected to 60 minutes of warm ischemia before fl ush and harvest, followed by 2 hours of cold storage before implantati on. After 21 days of immunosuppression with prednisone, azathioprine, and cyclosporine, pulmonary function was assessed. Bronchial viability was evaluated with bronchoscopy and, at autopsy, followed by histolog ic analysis. Results: Implantation time did not differ significantly b etween the control group and the experimental group (59.6 +/- 2.1 vers us 64.4 +/- 2.9 minutes, p = 0.24). Control swine exhibited no evidenc e of ischemic injury to the donor bronchus. In contrast, six of nine l ungs procured from non-heart-beating donors showed evidence of ischemi c bronchial injury (p = 0.031 versus control). Findings ranged from hy povascular edematous mucosa to necrosis and sloughing of the mucosa th roughout the entire donor bronchial tree. The remaining three non-hear t-beating donor lungs exhibited normal lung function and bronchial hea ling. Conclusions: We conclude that 60 minutes of warm ischemia for lu ngs procured from non-heart-beating donors results in impaired bronchi al viability with current preservation techniques. Thirty minutes of w arm ischemia may be the acceptable limit for lung procurement from non -heart-beating organ donors.