Influence of Preoperative Portal Hypertension and Graft Size on Portal Blood Flow Velocity in Recipient After Living Donor Liver Transplantation With Right-Lobe Graft

OBJECTIVE. The purpose of this study was to determine the range of portal blood flow velocity at Doppler sonography of recipients without major complications after right-lobe living donor liver transplantation and to explore factors affecting portal blood flow velocity. MATERIALS AND METHODS. Seventy-one patients (59 men, 12 women; mean age, 48.1 +/- 8.8 [SD] years; range 19-69 years) who underwent right-lobe living donor liver transplantation were enrolled. At preoperative Doppler sonography, peak portal blood flow velocity was measured at the main portal vein. On CT scans, varix score was calculated by subcategorization and grading of varices, and splenic volume was measured. The recipient's body weight and the graft weight were measured, and the graft-to-body weight ratio was calculated. Postoperatively, peak portal blood flow velocity of the recipient portal vein was measured at Doppler sonography on the first three postoperative days. The correlations between preoperative peak portal blood flow velocity, varix score, splenic volume, recipient body weight, graft weight, graft-to-body weight ratio, and recipient portal blood flow velocity were evaluated with Pearson's and Spearman's tests. Multiple regression analysis was performed to determine the factors independently correlated with recipient portal blood flow velocity. RESULTS. The mean peak recipient portal blood flow velocity was 47 +/- 14 cm/s (range, 23-86 cm/s). Portal blood flow velocity increased significantly as varix score increased (r = 0.463, p < 0.001). Weak positive correlations were found between portal blood flow velocity and graft weight (r = 0.255, p = 0.032) and graft-to-body weight ratio (r = 0.242, p = 0.042). Multiple regression analysis showed varix score and graft-to-body weight ratio independently correlated with portal blood flow velocity (beta = 2.496, p < 0.001; beta = 19.791, p = 0.014). CONCLUSION. Depending on the severity of preoperative portal hypertension and graft size, recipient portal blood flow velocity has a wide range in the days immediately after right-lobe living donor liver transplantation.