Optimizing the Regional Distribution of Organ Procurement Organizations

该项目涉及器官移植区域的设计。目前有超过82000名美国人在等待器官移植，而且这个数字还在增加。通过优化器官移植的区域，这项研究将提高匹配的质量。此外，通过明确地模拟公平问题，这项研究可以用来确保所有群体都能公平地获得器官进行移植。前面的工作将从三个重要方向展开。第一个将仔细模拟器官移植的复杂性质，以估计每个潜在区域内器官移植的预期数量和质量。这将涉及人口统计学和生理学建模。第二个问题将考虑器官移植系统内的公平性。这大致相当于所有公民都应该有同等机会获得器官的概念。公平的概念经常与医疗效率相冲突。这项研究将考虑平衡这些相互竞争的利益的各种方法。第三部分将开发解决这些研究中出现的大规模整数规划问题的方法。借鉴以前的工作，特别是航空公司的规划，我们将开发最先进的优化方法来解决这些难题。我们将使用分支和价格框架，使用专门的技术来分支和解决子问题。为了肝脏移植的目的，美国目前分为59个OPO，这些OPO聚集在11个地区。器官更可能停留在OPO和它们起源的区域。由于器官移植的层级性质，这些区域的组成可能会极大地影响器官移植的数量和质量，以及所有人都能公平获得器官等其他问题。从医疗效率的角度来看，一个理想的地区人口众多，因此可以进行多次匹配，但地理上紧凑，因此器官不需要长途旅行。然而，使用这些地区往往会使该国人口稀少的地区获得器官的机会大大减少。该提案涉及以下问题：在兼顾医疗效率和公平的情况下，应如何将OPO组织到最佳设置的区域？重点将放在肝移植上，但结果将适用于其他器官。

This project addresses the design of regions for organ transplantations. Over 82 thousand Americans are currently waiting for an organ transplant, and this number is still increasing. By optimizing regions for organ transplantation this research will increase the quality of the matches. Furthermore, by explicitly modeling equity issues, this research can be used to ensure that all groups have fair access to organs for transplants. The previous work will extend in three important directions. The first will model the complex nature of organ transplantation carefully to estimate the expected number and quality of organ transplants within each potential region. This will involve both demographic and physiological modeling. The second will consider fairness within an organ transplantation system. This is roughly equivalent to the notion that all citizens should have comparable access to organs. The notion of equity is often in conflict with medical efficiency. This research will consider various ways of balancing these competing interests. The third will develop methods for solving the large-scale integer programs arising in these studies. Borrowing ideas from previous work, particularly airline planning, we will develop state-of-the-art optimization methods for solving these difficult problems. We will use a branch-and-price framework, using specialized techniques for branching and solving the sub problems.For purposes of liver transplantation, the United States is currently divided into 59 OPOs, which are aggregated into 11 regions. Organs are more likely to stay in the OPO and region where they originate. Due to the hierarchical nature of organ transplantation, the composition of these regions can greatly affect the number and quality of organ transplantations, as well as other concerns, such as fair access to organs for all. From the point of view of medical efficiency, an ideal region has a high population so many matches are possible, but is geographically compact, so that organs need not travel long distances. However, employing such regions tends to leave the sparsely populated parts of the country with significantly lower access to organs. This proposal addresses the following question: How should the OPOs be organized into the best set regions, considering both medical efficiency and equity? The focus will be on the liver transplantation, but the results will apply to other organs.