Market Design for Kidney Exchange∗

The National Organ Transplant Act of 1984 makes it illegal to buy or sell a kidney in the US, thus making donation the only viable option for kidney transplantation. A transplanted kidney from a live donor survives significantly longer than one from a deceased donor (see e.g. Mandal et al. 2003). Hence, live donation is always the first choice for a patient. Moreover, there is a significant shortage of deceased donor kidneys. There are two kidneys in the human body. One healthy kidney is more than enough for its healthy functioning. Since the risks associated with donation surgery and follow-up have decreased with the advancement of new medical and surgical techniques, live donation has been the increasing source of overall donations. Usually, a live donor is a relative or friend of the recipient and is willing to donate only if that particular recipient is going to receive a transplant. That is, she is a directed live donor. However, a recipient is often unable to receive a willing live-donor’s kidney because of blood-type incompatibility or antibodies to one of the donor’s proteins (aka a positive crossmatch). Medical doctor F. T. Rapaport (1986) proposed live-donor paired kidney exchanges between two such incompatible recipient-donor pairs: the donor in each pair gives a kidney to the other pair’s compatible recipient. ∗This survey is prepared for the Oxford Handbook of Market Design edited by Z. Neeman, M. Niederle, and N. Vulkan. †E-mail: [email protected]; URL: www2.bc.edu/ ̃sonmezt ‡E-mail: [email protected]; URL: www2.bc.edu/ ̃unver About 79,000 patients were waiting for a deceased donor kidney transplant in the United States as of March 2009. In 2008, about 16,500 transplants were conducted, about 10,500 from deceased donors and 6,000 from living donors, while about 32,500 new patients joined the deceased donor waiting list and 4,200 patients died while waiting for a kidney (according to SRTR/OPTN national data retrieved at http://www.optn.org on 3/17/2009). Recently medical literature started to use the term kidney paired donation instead of kidney exchange.