Donor safety of remnant liver volumes of less than 30% in living donor liver transplantation: A systematic review and meta-analysis

PurposeThis meta-analysis aimed to investigate the acceptability of donor remnant liver volume (RLV) to total liver volume (TLV) ratio (RLV/TLV) being <30% as safe in living donor liver transplantations (LDLTs). MethodsOnline databases were searched from January 2000 to June 2022. Pooled odds ratios (ORs) and standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using fixed- or random-effects model. ResultsOne prospective and seven retrospective studies comprising 1935 patients (164 RLV/TLV <30% vs. 1771 RLV/TLV & GE;30%) were included. Overall (OR = 1.82; 95% CI [1.24, 2.67]; p = .002) and minor (OR = 1.88; 95% CI [1.23, 2.88]; p = .004) morbidities were significantly lower in the RLV/TLV & GE;30% group than in the RLV/TLV <30% group (OR = 1.82; 95% CI [1.24, 2.67]; p = .002). No significant differences were noted in the major morbidity, biliary complications, and hepatic dysfunction. Peak levels of bilirubin (SMD = .50; 95% CI [.07, .93]; p = .02) and international normalized ratio (SMD = .68; 95% CI [.04, 1.32]; p = .04) were significantly lower in the RLV/TLV & GE; 30% group than in the RLV/TLV <30% group. No significant differences were noted in the peak alanine transferase and aspartate transaminase levels and hospital stay. ConclusionsConsidering the safety of the donor as the top priority, the eligibility of a potential liver donor in LDLT whose RLV/TLV is expected to be <30% should not be accepted.