Donor type impact on ischemia-reperfusion injury after lung transplantation.

Background: Extended criteria donors, non-heart-beating donors (NHBD), and living donation are options to overcome the organ shortage for lung transplantation (LTx). However little is known about the impact of the donor lung on ischemia-reperfusion injury (IRI), which often leads to high mortality rates.

Methods: Recipient pigs (N=32) were divided equally into 4 groups according to their donor status: (1) living donor=control group, (2) conventional heart-beating donor, (3) non-heart-beating donor according to Maastricht category I (NHBD-I), and (4) Maastricht category IV (NHBD-IV). After cold flush and 3 hours of hypothermic preservation, a single left LTx was performed. Thereafter only the transplanted left lung was ventilated and perfused to assess isolated left lung function at 1 and 2 hours after LTx compared with before LTx.

Results: No significant differences were seen between the 4 groups regarding wet-to-dry weight ratio, mean airway pressure, or compliance. Arterial oxygenation and alveolar-arterial difference showed significant differences between the groups (p<0.05). Two-way analysis of variance (ANOVA) for the factors brain death and cardiac arrest found significantly increased alveolar-arterial differences for the brain-death group but not for the beating-heart donor group.

Conclusions: The use of lungs from brain-death donors and NHBDs has different effects on the occurrence of symptoms of IRI after LTx. Further observations and therapeutic strategies are necessary to minimize IRI when grafts from NHBDs are used.