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Toward a Fully Continuous Exchange Summary

Written By Wednesday, October 19, 2022 Add Comment Edit

Abstract

Purpose of Review

The Organ Procurement and Transplantation Network has chosen continuous distribution as its preferred framework for the next evolution of organ allocation policies. This review explains the approach, contrasting it with the current policy structure. It also provides an update on the continuous distribution of lungs proposal and shares ideas about how continuous distribution might improve kidney, liver, and heart allocation.

Recent Findings

Continuous distribution replaces an ordered list of discrete "classifications," or groups of patients, with a composite score that simultaneously accounts for all relevant factors and allows more nuance in balancing equity, utility, and efficiency. So-called edge cases are eliminated, for example, an extremely ill candidate not receiving a transplant due to being just barely on the other side of a geographic (or other) boundary. Simulation results predict a 30–50% reduction in waiting list deaths among lung candidates without increasing the proportion of organs requiring air travel.

Summary

Continuous distribution has the potential to markedly improve both transparency into the value judgments embedded in policy and patient outcomes, while still promoting the efficient management of organ placement. The framework enables "smarter," not necessarily broader, distribution of organs. Continuous distribution is also highly flexible, such that future modifications (e.g., to rebalance utility vs. efficiency) should be easier to implement.

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Acknowledgements

This work was funded by the U.S. Department of Health and Human Services, Health Resources and Services Administration (HRSA), Healthcare Systems Bureau, Division of Transplantation under contract number HHSH250201900001C, and was conducted under the auspices of the United Network for Organ Sharing (UNOS), the contractor for the Organ Procurement and Transplantation Network (OPTN). The interpretation and reporting of these data are the responsibility of the author(s) and in no way should be seen as an official policy of or interpretation by the OPTN or the US Government. Several improvements to this manuscript were suggested by David Klassen, MD, and James Alcorn, JD, and are greatly appreciated.

MELD model for end stage liver disease; KDPI kidney donor profile index; LAS lung allocation score; CPRA calculated panel reactive antibodies

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  1. United Network for Organ Sharing, Richmond, VA, USA

    Darren Stewart

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Correspondence to Darren Stewart.

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Stewart, D. Moving Toward Continuous Organ Distribution. Curr Transpl Rep 8, 301–313 (2021). https://doi.org/10.1007/s40472-021-00352-z

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