Using MDPs to Optimize Living Donor Liver Transplants

描述（由申请人提供）： 在1990年之前几乎闻所未闻，使用活体捐赠者进行肝移植的情况一直在增加，现在每年有超过500例移植。虽然活体供体移植有几个潜在的优势，该程序将活体供体置于死亡和发病的风险中，因此，应尽可能适当和有效地进行。在这个探索性的应用中，我们建议使用马尔可夫决策过程（MDP，这是专门设计用于分析不确定条件下的顺序决策的数学工具）来评估活体肝移植的最佳时机。R21开发应用程序的总体目标是深入了解影响这一时机决定的因素，以便尽可能谨慎和成功地做出移植决定。具体而言，这项工作旨在实现两个具体目标： 目的1：根据受体和供体的特点，评估活体供肝移植的最佳时间。活体器官捐献者的接受发生在器官共享处等待名单之外，不受外部分配和选择规则的约束。因此，唯一需要做出的决定是进行移植的适当时间（在健康状况下降的临床方面）。我们建议建立一个MDP来评估这个问题。 目的2：评估在接受活体供者移植之前进行尸体移植的最佳等待时间。因为存在一个愿意的潜在活体捐赠者并不排除在尸体等待名单上，因为潜在的接受者可能不想让捐赠者冒生命危险，更现实的问题是：“在接受活体捐赠者之前，我应该在尸体名单上等待多久？“在AIM 1中开发的MDP将得到增强，以纳入提供不同质量尸体器官的顺序可能性。 这项工作是创新和发展的，因为MDP通常不用于评估医疗决策，即使它们是专门开发来评估不确定性下的顺序决策（这恰当地描述了临床医生做出的大多数决策）。该研究团队在模拟肝脏疾病和移植过程的进展以及将数学模型从管理科学应用于健康和医学问题方面拥有丰富而独特的经验。我们寻求扩展我们的医学和工业工程之间的成功合作的历史，研究这些复杂的数学模型的有用性时，应用到一个真实的和复杂的医疗决策。

DESCRIPTION (provided by applicant): Virtually unheard of prior to 1990, the use of living donors for liver transplantation has been increasing and now represents over 500 transplants per year. Although living donor transplantation has several potential advantages, the procedure places the living donor at risk of death and morbidity and, therefore, should be undertaken as appropriately and efficiently as possible. In this exploratory application, we propose to use Markov decision processes, (MDPs, which are mathematical tools specifically designed to analyze sequential decisions under conditions of uncertainty) to evaluate the optimal timing of living donor liver transplantation. The overall goal of this developmental R21 application is to provide insights into the factors that affect this timing decision so that transplant decisions can be made as carefully and successfully as possible. Specifically, this work seeks to fulfill two specific aims: Aim 1: Evaluate the optimal time to transplant a living donor liver given the characteristics of the recipient and donor. Acceptance of a living donor organ occurs outside of the UNOS waiting list and is not subject to external allocation and selection rules. Therefore, the only decision to be made is the appropriate time (in clinical terms of declining health status) to conduct the transplant. We propose to build an MDP that will evaluate this question. Aim 2: Evaluate the optimal waiting time for a cadaveric transplant prior to accepting a living donor transplant. Because the existence of a willing potential living donor does not preclude listing on the cadaveric wait list, and because a prospective recipient may not want to place that donor at mortal risk, the more realistic question is: "How long should I wait on the cadaveric list before accepting a living donor?" The MDP developed in AIM 1 will be enhanced to incorporate the sequential possibility of being offered cadaveric organs of varying quality. The work is innovative and developmental as MDPs have not typically been used to evaluate medical decisions, even though they were specifically developed to evaluate sequential decisions under uncertainty (which aptly describes most decisions clinicians make). The investigative team has substantial and unique experience in modeling the progression of liver disease and the transplant process, and the application of mathematical models from management science to problems in health and medicine. We seek to extend our history of successful collaboration between Medicine and Industrial Engineering, to investigate the usefulness of these sophisticated mathematical models when applied to a real and complex medical decision.