Liver graft‐to‐spleen volume ratio as a useful predictive factor of the early graft function in children and young adults transplanted for biliary atresia: a retrospective study

A graft volume/standard liver volume ratio (GV/SLV) > 35% or graft/recipient weight ratio (GRWR) > 0.8% has been considered as a standard criteria of graft selection. Even if the graft size meets these selection criteria, small‐for‐size syndrome can still occur depending on the portal venous flow (PVF). The aim of this study was to identify other factors contributing to portal hyperperfusion and the post‐transplant course, focusing on the graft volume‐to‐spleen volume ratio (GV/SV). Thirty‐seven BA patients who underwent living donor liver transplantation were reviewed retrospectively. First, we evaluated the preoperative factors contributing to portal hyperperfusion. Second, we evaluated the factors contributing to post‐transplant complications, such as thrombocytopenia, hyperbilirubinemia, and coagulopathy. The GV/SLV was >35% in all cases; however, portal hyperperfusion (≥250 ml/min/100 g graft) was found in 12 recipients (35.3%). Furthermore, although the GRWR was >0.8% in over 90% of cases, portal hyperperfusion was found in 10 recipients (32.3%). In contrast, the GV/SV showed a significant correlation with the PVF after reperfusion. If the GV/SV was <0.88, about 80% of recipients developed portal hyperperfusion. Furthermore, the GV/SV also showed a significant correlation with post‐transplant persistent thrombocytopenia and hyperbilirubinemia. The GV/SV < 0.88 predicts portal hyperperfusion, post‐transplant persistent thrombocytopenia, and hyperbilirubinemia.