Outcomes of Donor/Recipient Size-mismatched Lung Transplantation.

Background: Donor/recipient (D/R) size matching is crucial to achieve proper organ allocation and outcome for lung transplantation (LT). However, studies in this regard have not shown consistent results. We analyzed the results of size-mismatched LT focusing on primary graft dysfunction (PGD) and survival.

Methods: A total of 446 patients underwent LT between January 2010 and December 2022. After exclusion, the patients were divided into 3 groups according to the donor/recipient size; D/R ratio >120% was grouped as Over (n = 87), 120%≥D/R ratio≥80% was grouped as Normal (n = 271), 80%>D/R was grouped as Under (n = 19). Early and long-term outcomes were analyzed.

Results: Recipient height, weight, and proportion of male were the highest in the Under group, followed by the Normal and Over groups (P < 0.001). The ratio of extracorporeal membrane oxygenation weaning in the operating room was highest in the Under group, followed by the Normal and Over groups (P : 0.04). The proportions of PGD grade 3 within 48 h and 72 h were highest in the Over group, followed by the Normal and Under groups (P : 0.007 and 0.016, respectively). There was no statistical difference in the pulmonary function test results between the groups at 12 months postoperative follow-up. The 5-year survival rate did not differ among the groups (60.9% vs 56.8% vs 54.7%, Under vs Normal vs Over, P : 0.833) CONCLUSIONS: Although oversized D/R-matched LT demonstrated late recovery during the early postoperative period, their long-term results were non-inferior in terms of the D/R size ratio.