Allocation of deceased donor kidneys: past, present, and future.

The manner in which deceased donor kidneys are allocated has broad relevance to the care of patients with end-stage renal disease. An algorithm governing the allocation of deceased donor kidneys has been applied in the United States since 1987. Adjustments were made to facilitate the national sharing of highly matched kidneys, but the main components of the algorithm remained largely unchanged. In ensuing years, the number of patients on the waiting list has increased steadily while the supply of kidneys has remained constant. The waiting time for an organ now is measured in years, and the allocation of organs has become unpredictable. As of October 2002, several important changes have been made to the algorithm. These changes are designed to increase the relative number of minority patients who undergo transplantation and the use of extended-criteria donor kidneys. They also have practical implications for the management of patients on the waiting list. The rationale behind these changes is discussed in the context of the ethical underpinnings of kidney allocation.