Functional Shunt with Small-for-Size Graft in Auxiliary Liver Transplantation for Portal Hypertension

BACKGROUND Portal hypertension (PH) in end-stage liver disease remains a critical challenge, with traditional liver transplantation (LT) requiring a strict graft size criterion: graft-to-recipient weight ratio (GRWR) ³0.8%. Using small-for-size graft (SFSG) in auxiliary liver transplantation (ALT) as a "functional shunt" may offer a novel approach by retaining part of the native liver to buffer PH. MATERIAL AND METHODS A retrospective analysis was performed on 6 PH patients who underwent functional shunt with SFSG in ALT at Beijing Friendship Hospital from 2014 to 2018. Intraoperative parameters and postoperative monitoring data were collected to analyze the hepatic hemodynamic alterations. We performed descriptive analyses on relevant indicators to summarize hepatic hemodynamic changes and clinical outcomes after functional shunt. RESULTS No patients developed SFSS after functional shunt. Following the functional shunt procedure, the portal vein (PV) blood flow of the remnant native liver gradually declined to no perfusion, while hepatic artery flow velocity increased as part of a compensatory arterial buffer response. The PV blood flow of the graft increased gradually during the early postoperative period, but declined between day 5 to 10 after surgery, due to rising portal perfusion resistance. A subsequent increase was observed around day 10, and reached its peak approximately 1month after surgery, followed by a gradual decline toward stabilization. Abdominal drainage volume peaked between day 5 to 10 after surgery, and then decreased slowly, resolving around 1 month after functional shunt. CONCLUSIONS Functional shunt with SFSG in ALT appears to be promising and safe, and may expand the donor pool for PH patients who would otherwise be excluded from transplantation due to graft size criteria.