The role of graft to recipient weight ratio on enhanced recovery of the recipient after living donor liver transplantation – A systematic review of the literature and expert panel recommendations

Background: There continues to be debate about the lower limit of graft-to-recipient weight ratio (GRWR) for living donor liver transplant (LDLT). Objectives: To identify the lower limit of GRWR compatible with enhanced recovery after living donor liver transplant and to provide international expert panel recommendations. Data sources: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. Methods: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Studies assessing how GRWR affects recipient outcomes such as small for size syndrome, other complications, patient and graft survival, and length of stay were included. Protocol registration: CRD42021260794. Results: Twenty articles were included in the qualitative synthesis, and all were retrospective observational studies. There was heterogeneity in the definition of study cohorts and key outcome measures such as small-for-size syndrome. Most studies lacked risk adjustment given limited single-center sample size. GRWR of ≥.8% is associated with enhanced recovery. Recipients of grafts with GRWR <.8%, however, were found to have similar outcomes as those with ≥.8% when appropriate consideration is made for portal flow modulation and recipient illness severity. Conclusions: GRWR ≥.8% is often compatible with enhanced recovery, but grafts <.8% can be used in selected LDLT recipients with optimal donor-recipient selection, surgical technique, and perioperative management (Quality of Evidence; Low | Grade of Recommendation; Strong).