Intraoperative hepatic flow thresholds predicting primary graft dysfunction and early graft survival after liver transplantation.

Adequate intraoperative hepatic perfusion is essential for early graft function after liver transplantation, yet standardized thresholds for portal vein and hepatic artery flow are lacking. This retrospective cohort study evaluated the prognostic value of graft weight-adjusted intraoperative hepatic inflow measurements for predicting primary graft dysfunction and early graft survival. A total of 472 adult recipients of deceased-donor orthotopic liver transplantation were included. Hepatic artery flow and portal vein flow were measured immediately after reperfusion using a transit-time flowmeter and normalized per 100 g of graft weight. Primary graft dysfunction occurred in 11.4% of recipients, and overall 1-year graft survival was 90.5%. Hepatic artery flow below 8.5 mL/min/100 g was independently associated with primary graft dysfunction, together with prolonged cold ischemia time. Hepatic artery flow demonstrated moderate discriminatory ability for predicting primary graft dysfunction, whereas portal vein flow showed limited accuracy for this outcome. In contrast, portal vein flow below 70 mL/min/100 g was associated with reduced 1-year graft survival. These findings indicate that graft weight-adjusted intraoperative hepatic inflow measurements provide clinically relevant prognostic information for early outcomes after liver transplantation. Hepatic artery flow appears primarily related to early graft dysfunction, while portal vein flow is more closely associated with early graft survival. Intraoperative flow assessment may therefore serve as an adjunctive tool for early risk stratification and real-time decision-making, although multifactorial approaches are required to improve prediction of long-term graft outcomes.