Critical graft size in adult-to-adult living donor liver transplantation: Impact of the recipient's disease

Abstract

The aim of this study is to analyze the impact of the recipient's disease severity on graft size requirements and outcome in adult‐to‐adult living donor liver transplantation. A limiting factor in adult‐to‐adult living donor liver transplantation has been adequacy of graft size. A minimal graft‐recipient weight ratio (GRWR) of 0.8% to 1% has been suggested, without taking the recipient's disease into account. Forty adults underwent liver transplantation using left (n = 10; mean weight, 481 ± 83 g) or right lobes (n = 30; mean weight, 845 ± 182 g). We recorded graft survival, Child‐Turcotte‐Pugh score, and occurrence of small‐for‐size syndrome (poor bile production, prolonged postoperative prothrombin time, and cholestasis without ischemia markers). Small grafts were defined as GRWR of ≤0.85%. Large grafts were defined as GRWR greater than 0.85%. Six patients died within 6 months of transplantation (early patient survival rate, 85%); two patients died late of tumor recurrence. Among transplant recipients with normal liver function or Child's class A, there was no significant difference with the use of small (n = 6) or large (n = 9) grafts (graft survival rates, 83% v 88%, respectively; P = .65). Among patients with Child's class B or C, graft survival rates were 74% in recipients of large grafts (n = 19) and 33% in recipients of small grafts (n = 6; P = .023). Five of 6 patients with Child's class B or C who received small grafts developed small‐for‐size syndrome; 2 patients died (1 patient after retransplantation) and 3 patients survived (2 patients after retransplantation). Graft function and survival are influenced not only by graft size, but also by pretransplantation disease severity. GRWR as low as 0.6% can be used safely in patients without cirrhosis or in patients with Child's class A. Transplant recipients with Child's class B or C require a GRWR greater than 0.85% to avoid small‐for‐size syndrome and related complications.