Objective: To evaluate the impact of graft size on recipients in living donor liver transplantation (LDLT) to establish a clinical guideline for the minimum requirement.
Summary background data: Although the minimum graft size required for LDLT has been reported to be 30% to 40% of graft volume (GV)/standard liver volume (SLV), the safety limit of the graft size was unknown.
Methods: A total of 33 cases of LDLT, excluding auxiliary transplantation, were reviewed with a minimum observation period of 4 months. The 33 patients were divided into three groups according to GV/SLV: medium-size graft group, small-size graft group, and extra-small graft group. The effect of GV/SLV on graft function, graft regeneration, and survival was evaluated.
Results: The overall patient survival rate was 94% at a mean follow-up of 15 months with a minimum observation period of 4 months. There were no statistically significant differences in postoperative bilirubin clearance, alanine aminotransferase, prothrombin time, and frequency of postoperative complications among the three groups. One week after transplantation, the regeneration rate (GV at 1 week/harvested GV) in the extra-small and small groups was significantly higher than that of the medium group. The graft and patient survival rates were both 100% in the extra-small group, 75% and 88% in the small group, and 90% and 95% in the medium group.
Conclusions: Small-for-size grafts less than 30% of SLV can be used with careful intraoperative and postoperative management until the grafts regenerate.