Practical and ethical considerations in kidney paired donation and emerging liver paired exchange.

Since the first kidney paired donation (KPD) transplant in the United States in 1999, the volume and scope of KPD has expanded substantially, accounting for nearly 20% of living donor kidney transplants in 2021-2022. This review article discusses the practical and ethical issues specific to paired donor exchange that patients, transplant centers, and exchange programs commonly encounter. Access to paired donor exchange and education of candidates regarding the potential benefits, risks, and logistics of KPD are important considerations. Transplant centers and patients must consider practical issues including wait times, allocation and matching strategies, assessment of organ quality, complex donors, cold ischemia time, and risks of broken chains. Protections available to donors from current KPD programs, the potential psychosocial effects, and the ethical concerns related to variable access and the proprietary nature of private exchange programs are also discussed. More detailed, timely data collection at a national level, and ability to merge national data with individual donor exchange registries will enable the analysis of the impact and outcomes of future trends in paired donation. KPD experience and key concepts may inform liver paired exchange, which has been used internationally to expand living donor liver transplantation and is emerging in the United States.