A survival-based scoring-system for initial graft function following orthotopic liver transplantation

Abstract

Initial graft function following orthotopic liver transplantation is a major determinant of postoperative survival and morbidity. Despite several efforts to provide scoring-systems for initial graft function, there is still a lack of a generally accepted classification scheme. The previously published systems assessed initial graft function based on the first postoperative days or weeks using liver-related laboratory parameters. It was shown that in most cases the scoring-systems did not correlate with patient survival. We intended to refine the definition of initial graft function in order to provide a survival based classification system. In a retrospective analysis of 761 patients following primary liver transplantation, a new scoring-system for early postoperative graft function was developed. Statistically significant differences in long term survival were calculated for ALAT, ASAT, bile production and prothrombin activity on days 1, 3, 7, 14. Points were then assigned according to the degree of survival: improved survival=1 point, poor survival=2 points. Patients were split into three groups corresponding to initially good, moderate and poor function. Applying this score, early and late patient survival rates and incidence of initial non-function were statistically significantly different. This was in contrast to the Gonzalez and the Ploeg-Maring classification scales, which are based on arbitrarily chosen cutoff levels. Retransplantation rates and postoperative morbidity were comparable both for the new and the older systems. We can conclude that the presented refined scoring-system for initial graft function provides a significant correlation to patient survival and initial non-function. We recommend the refined system for future studies.