2 Distribution indicates the geographic units in the country where donated livers are matched to a priority-ranked list of candidates according to the allocation scheme within the distribution unit. 3 Allocation is defined as the order of patients on a particular waiting list based upon medical urgency 3 and has been based upon the MELD score since 2002. The determination of which patient receives an organ is dependent upon 2 factors: allocation and distribution. 2 The MELD score, which is calculated from serum bilirubin, international normalized ratio of prothrombin time, and serum creatinine, offers an objective score that accurately predicts the risk of shortterm mortality from chronic liver disease. 1 Following publication of the Final Rule, the Organ Procurement and Transplant Network (OPTN) adopted the Model for End-Stage Liver Disease (MELD) score to prioritize patients on the liver transplant waiting list. 1 The Final Rule also stated that access to a transplant should not be affected by place of residence or listing. In 2000, the US Department of Health and Human Services published the Final Rule, which, in part, established principles for the allocation of deceased donor livers, including prioritizing candidates based upon medical urgency. This paper reviews several of the key changes to the liver allocation system that have occurred since the implementation of MELD allocation in 2002 and provides an overview of potential changes to the system. Despite all of these changes, variation in access to liver transplantation continues to exist, and, thus, the liver transplant community continues to examine new ways to address geographic disparities. As a result, numerous policy changes have been adopted throughout the years that have broadened the sharing of organs through wider geographic sharing. The liver transplant community has worked to develop methods to reduce these geographic disparities and to reexamine how MELD exception points are granted to certain patient populations.
Both the Organ Procurement and Transplant Network Board of Directors and the Health Resources and Services Administration have determined these geographic disparities to be unacceptable. Significant geographic variation in the access to liver transplantation exists throughout the United States. In addition, certain patient populations, such as patients with hepatocellular carcinoma and portopulmonary hypertension, receive MELD exception points to account for their increased waitlist mortality, which is not reflected by their MELD score. The liver transplant allocation system is currently based upon the Model for End-Stage Liver Disease (MELD) score and allocates organs preferentially to patients with the highest scores (ie, the sickest patients) within a defined geographic unit.
0 kommentar(er)
