Kidney exchange simulation and optimization

Abstract

One of the challenges in a kidney exchange program (KEP) is to choose policies that ensure an effective and fair management of all participating patients. In order to understand the implications of different policies of patient allocation and pool management, decision makers should be supported by a simulation tool capable of tackling realistic exchange pools and modeling their dynamic behavior. In this paper, we propose a KEP simulator that takes into consideration the wide typology of actors found in practice (incompatible pairs, altruistic donors, and compatible pairs) and handles different matching policies. Additionally, it includes the possibility of evaluating the impact of positive crossmatch of a selected transplant, and of dropouts, in a dynamic environment. Results are compared to those obtained with a complete information model, with knowledge of future events, which provides an upper bound to the objective values. Final results show that shorter time intervals between matches lead to higher number of effective transplants and to shorter waiting times for patients. Furthermore, the inclusion of compatible pairs is essential to match pairs of specific patient–donor blood type. In particular, O-blood type patients benefit greatly from this inclusion.

Keywords:

• kidney exchange
• simulation
• optimization

Acknowledgements

This work is financed by the ERDF European Regional Development Fund through the COMPETE Program (operational program for competitiveness) and by National Funds through the FCT Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project “mKEP: Models and optimisation algorithms for multi-country kidney exchange programs.” FCT ref: PTDC/IIM-GES/2830/2014.

Notes

1 This examination is done without carrying out a serologic crossmatch such as a Complement Dependent Cytotoxic (CDC) or flowcytometric crossmatch.

2 https://www.unos.org/wp-content/uploads/unos/CPRA_Patients?e4f722.

3 A high PRA level is explained by a patient having been submitted to blood transfusions or transplants in the past.

4 Obtained from http://www.transplantatiestichting.nl/.