The objective of this study was to compare harmonic scalpel for short hepatic vein transection with conventional ligation during recipient hepatectomy with caval preservation. Sixteen patients undergoing elective living donor liver transplantation were randomized into 2 groups. We recorded number, diameter, and location of each short hepatic vein, procedure time, central venous pressure, and degree of liver failure (Child-Pugh and Model for End stage Liver Disease scores). As an end point, we observed the intraoperalive and postoperative bleeding rates of the transected veins. We transected 144 veins of mean diameter of 2.6 +/- 1.8 mm (range, 1-12 mm). Mean number of short hepatic veins in each person was 9 (range, 5-16). Harmonic scalpel was safe for veins with a diameter <= 2 mm; these veins were more prone to bleeding with conventional ligation. Bleeding rate was higher after ligation of veins in the upper half than the lower half of the cava (37% vs 21%; P = .04). Both total and per vessel procedure time did not differ between the groups. No postoperative bleeding complications occurred. Transection of veins with a diameter <= 2 mm by harmonic scalpel was as safe as conventional ligation. Harmonic scalpel transection of small hepatic veins (<= 2 mm) can be even safer than conventional control by knot tying, particularly in narrow areas.