Improving the Allocation of Donor Organs: Treating to the Priority in Heart Transplantation
By Amira Hijazi
Organ transplantation improves quality of life and saves around $300,000. The TA62 session held Tuesday morning involved different talks that share the same goal: improving the allocation of donor organs. Dr. Sait Tunc, Assistant Professor from Virginia Tech, started the session by presenting a queueing model to analyze the gaming decisions of heart transplant centers. Gaming decisions happen because of the therapy-based prioritization for heart allocation. Dr. Tunc showed that gaming is more prominent when there is a lower death rate of urgent patients and if there is a higher competing demand. However, if organs are too scarce, the threshold-based gaming policy never exceeds a certain ratio.
The second presenter, Dr. Masoud Barah, a postdoctoral research fellow at Northwestern University, talked about his simulator for kidney acceptance rejection decisions, which he calls Karda. Candidates for the deceased donor kidneys are in a long waitlist before they are offered an organ. Once offered, a recipient and the physician have a short window to accept or reject the offer. By using, a stochastic tree-based approach, Dr. Barah showed that Karda does project graft failure and identifies patients who would benefit from transplanting marginal kidneys. Moreover, the survival loss of a discarded kidney is measurable with Karda. This talk assumes that allocation of a deceased donor kidney has been made. However, as Dr. Barah explained, there is a long waitlist before a candidate is offered a kidney.
To analyze the waiting list for a deceased donor kidney, Dr. Nikhil Agarwal, Associate Professor of Economics at MIT, proposed an empirical framework based on the optimal stopping problem. The output of the model showed that there is a substantial match-specific heterogeneity in values. Moreover, younger donors are preferable than older ones. Finally, Dr. Agarwal presented a dynamic assignment design that increases patient welfare by 14.2%.
The last talk was presented by Dr. Mohammad Delasay from Stony Brooke University. In his talk, Dr. Delasay presented a multidimensional queuing model to model the waiting list of kidney allocation. Conditions of participation (COP) was issued by the Centers for Medicare and Medicaid Services to make sure that transplant centers meet specific conditions. COP penalizes centers with lower-than-expected post-transplant survivals. However, the results of the analysis done by Dr. Delasay show that these conditions are inappropriate and lack a net benefit approach by only focusing on post-transplant outcomes.