Revisiting the Prognostic Influences of Donor-Recipient Size Mismatch in Deceased Donor Liver Transplantation

Background: Liver transplantation (LT) outcomes are influenced by donor-recipient size mismatch. This study re-evaluated the impact on graft size discrepancies on survival outcomes. Methods: Data from 53 389 adult LT recipients from the United Network for Organ Sharing database (2013-2022) were reviewed. The study population was divided by the body surface area index (BSAi), defined as the ratio of donor body surface area (BSA) to recipient BSA, into small-for-size (BSAi < 0.78), normal-for-size (BSAi 0.78-1.24), and large-for-size (BSAi > 1.24) grafts in deceased donor LT (SFSD, NFSD, and LFSD). Multivariate Cox regression and Kaplan-Meier survival analyses were conducted. SFSD was hazardous within 90 d post-LT because of vascular complications. Beyond 1 y, graft size did not affect graft survival. LFSD risk within the first year was mitigated with lower model for end-stage liver disease (MELD) 3.0 scores (<35) or shorter cold ischemia time (<8 h). Conclusions: The negative impacts on donor-recipient size mismatch on survival outcomes are confined to the first year post-LT. SFSD is associated with a slight decrease in 90-d survival rates. LFSD should be utilized more frequently by minimizing cold ischemia time to <8 h, particularly in patients with MELD 3.0 scores below 35. These findings could improve donor-recipient matching and enhance LT outcomes.