The idea of multiple-way barter exchanges of kidneys for transplants is not a new one. We’ve covered it on our pages before (see here and here). On April 5th, clinicians from Johns Hopkins went farther than anyone else before: the first six-way donor kidney swap.
Saturday’s surgeries were set into motion when five separate transplant candidates visited Johns Hopkins for evaluation, each with their own willing donor whose blood or tissue types were incompatible. Using a Hopkins-developed living donor matching system, the Hopkins transplant team introduced a so-called altruistic donor — one who volunteers a kidney to no particular recipient — into the mix and were able to arrange a six-way swap. This allowed all five original candidates to receive compatible kidneys from someone they had never met, while the remaining kidney went to the next patient on the United Network for Organ Sharing’s (UNOS) recipient list.
The Johns Hopkins transplant team pioneered the exchange of kidneys among incompatible donor-recipient pairs — a procedure called kidney paired donation (KPD). Johns Hopkins performed the first KPD triple transplant in 2003, the first triple domino transplant in 2005 and the first five-way domino transplant in 2006.
In a paper published last August in the British journal Lancet, Robert Montgomery, M.D., Ph.D., chief of the transplant division at Johns Hopkins Hospital, and a team of Johns Hopkins researchers laid out the blueprint for a wider system of pairing altruistic donors and incompatible recipient pairs to greatly increase the number of available organs and better serve the interests of both transplant donors and recipients.
Without a universal system of this kind in place, Montgomery says altruistic donors often end up on an Internet donation site or are subject to inconsistent allocation systems in which only a single patient benefits. For example, in some cases, the kidney goes to a patient deemed to have the best chance for long-term survival, while in others, the organ is given to a patient in greatest need or to someone at the top of the UNOS waiting list regardless of predicted outcome or need.
"With domino paired donation, all three of these ethical tenets are satisfied," says Montgomery. "The likelihood of a good outcome is increased by spreading the risk of recipient graft loss across more people. The neediest are served, since in many cases incompatible donor-recipient pools have a high proportion of patients who are hard to match. And fairness is served because the last paired donor’s kidney in the chain is allocated to the next compatible patient on the deceased donor waiting list."
In Saturday’s procedure, all six donor surgeries began simultaneously. The six donor kidneys remained in the same operating rooms, which was then sterilized and readied for the intended recipients.