Cellular Ex Vivo Lung Perfusion Beyond 1 Hour May Improve Marginal Donor Lung Assessment.

Background: Ex vivo lung perfusion (EVLP) permits extended evaluation of donor lungs for transplant. However, the optimal EVLP duration of Lund protocol is unclear. Using human lungs rejected for clinical transplant, we sought to compare the results of 1 versus 2 h of EVLP using the Lund protocol.

Methods: Twenty-five pairs of human lungs rejected for clinical transplant were perfused with the Lund EVLP protocol. Blood gas analysis, lung compliance, bronchoscopy assessment, and perfusate cytokine analysis were performed at both 1 and 2 h. Recruitment was performed at both time points. Donor lung transplant suitability was determined at both time points.

Results: All cases were divided into four groups based on transplant suitability assessment at 1 h and 2 h of EVLP. In group A (n = 10), lungs were judged suitable for transplant at both 1 and 2 h of EVLP. In group B (n = 6), lungs were suitable at 1 h but nonsuitable at 2 h. In group C (n = 2), lungs were nonsuitable at 1 h but suitable at 2 h. Finally, in group D (n = 7), lungs were nonsuitable for transplant at both time points. In both groups B and C (n = 8), the transplant suitability assessment changed between 1 and 2 h of EVLP.

Conclusions: In human lungs rejected for transplant, transplant suitability differed at 1 versus 2 h of EVLP in 32% of lungs studied. Evaluation of lungs with Lund protocol EVLP beyond 1 h may improve donor organ assessment.