BACKGROUND Little is known about the value of intraoperative hepatic artery (HA) flow measurement on the development of HA complications in orthotopic liver transplantation (OLT). We undertook this study to see whether assessing HA flow at the OLT helps predict posttransplant HA complications (HA thrombosis or stenosis). METHODS Four hundred and eleven consecutive OLT in 367 adult patients who received grafts between November 1992 and August 1995 were reviewed. Of these, 259 grafts in 255 patients with at least 1 year of follow-up and with complete data were studied. HA flow, portal vein flow, percentage of cardiac index going to HA (HA/CI), HA flow per 100 g of liver tissue, mean arterial pressure, central venous pressure, and CI were analyzed. Preservation injury was assessed by posttransplant alanine aminotransferase and aspartate aminotransferase levels. RESULTS Thirty-four patients with 35 grafts developed HA thrombosis or stenosis during a median follow-up time of 29 months. HA complications occurring within the first 100 days of OLT were classified as early complications. HA flow at the time of surgery and percentage of CI going to the liver were found to be significant variables in early HA complications. Hepatic hemodynamics were not different in the late HA complication group compared to the control. Systemic hemodynamics and posttransplant alanine amino-transferase and aspartate aminotransferase levels were similar in all three groups. Logistic regression analysis showed that patients with HA flows less than 400 ml/min were more than 5 times as likely to develop HA complications (risk ratio 5.1). CONCLUSIONS HA flow measurement should be obtained at the time of OLT and may help to predict early but not late posttransplant HA complications. Patients with HA flows less than 400 ml/min or HA/CI values of less than 7% may carry a higher risk for HA stenosis or thrombosis and may need close surveillance to detect such problems.