Split Liver Transplantation: An Analytical Decision Support Model

Split liver transplantation (SLT) is a procedure that can potentially save two lives using one liver, thus increasing the total utility derived from the limited number of donated livers available. It also can potentially improve equity, by giving transplant candidates who are physically smaller (including children) increased access to liver transplants. However, SLT is rarely used in the US. To help quantify the benefits of increased utilization of SLT and provide decision support tools, we introduce a deceased-donor liver allocation model with both efficiency and fairness objectives. In this model we formulate a multi-queue fluid system, incorporating the specifics of donor-recipient size matching and patients’ dynamically changing Model for End-Stage Liver Disease scores. Leveraging a novel decomposition result we find the optimal matching, enabling us to benchmark the performance of different allocation policies. Numerical results, utilizing data from UNOS, show that SLT can significantly increase total quality-adjusted life years, reduce patient deaths, and improve fairness among different patient groups.