Predicting Outcomes and Use and Abuse of Prognostic Models

The purpose of a national scheme for solid organ transplantation is to match donor organs with patients with failure of that organ. Allocation refers to prioritization of one potential recipient over all others who might receive that organ. Distribution refers to the movement of a donor organ to the location of the most highly prioritized potential recipient. This chapter discusses the evolution of the schemes for allocation, with the greatest emphasis on the practices in US. Organ allocation systems for liver transplantation (LT) are informed by two ethical principles: justice and utility. Implementation of the model for end-stage liver disease (MELD) score for liver allocation led to 12% reduction in LT waiting list registrations, due to decreased listing of patients with low MELD scores. Acute-on-chronic liver failure was recognized as an acute deterioration in the clinical condition of patients with chronic liver disease that is associated with a high mortality rate.