To the Editor:
Dr. Spital suggests that my proposal for voluntary exchanges of O-blood-type living donor kidneys intended for non-O-recipients “would not work in practice.” He offers no technical, medical objections. Rather he believes that, for psychological reasons, very few donors would participate and that doing so would require additional sacrifice on their part. He is concerned about uncertainty of predictions that the exchanged organ would be as good or better than the original donor's.
Predictions are always statistical, however, donor-recipient pairs could frequently be offered exchanges from compatible non-O-donors that are statistically superior. Every reason supports the belief that many exchanged organs would be better and no reasons predict inferiority. Donors could be significantly younger, better HLA matches or offer better kidney function. With sophisticated matching programs, almost all O-donor–recipient pairs could be offered statistically superior kidneys.
I don't understand why Dr. Spital believes such exchanges would require larger sacrifice and greater generosity. To the contrary, if I were an O-donor, I would be angered if I were not given the opportunity to exchange for a statistically better organ.
Voluntary exchanges do not require “predicting correctly” that the results would be as good or better. That is asking more than medical science can deliver. All that is required is the accurate claim that the odds are better with exchange. Given the data regarding the importance of donor age, HLA type and kidney function, that claim is not difficult to sustain. For reasons of blood type, hundreds of non-O-donors yearly are presently prevented from donating to their intended recipients. Almost all O-donor–recipient pairs should be able to be matched with non-O-donors offering statistically superior organs.
Dr. Spital correctly notes that exchanges could involve procurements at different hospitals from those of the donors' paired recipients, but they need not. The Washington Regional Transplant Consortium presently without significant complications procures organs from donors who decline to use the recipient's hospital. Exchanged organs could also be transported to the recipient's hospital.
I stand by my suggestion that O-donor/non-O-recipient pairs should be invited to consider voluntary exchanges and could almost always receive statistically superior organs. Often this could be done while offering non-O-donor-recipient pairs better organs than those from the deceased donor list. Sometimes what is disadvantageous to O-donor–recipient pairs won't be a problem for non-O-donor pairs. Clinicians failing to present voluntary exchanges are failing to serve their patients' interest. Of course, donor–recipient pairs should not be required (or even expected) to accept such offers, but it is hardly asking them to sacrifice if statistically better organs are offered. I find presenting voluntary exchanges morally imperative. Doing so would benefit both the O- and non-O-recipients while having helping worst off (O-blood candidates remaining on deceased donor wait lists). If only a small percentage of the O-donors presently donating to non-O's exchange their kidneys for statistically better organs, it will be enough to offset any increases in wait times from the live-donor/deceased donor exchanges for O's on the wait list that motivated the original discussion.