Liver blood flow after partial hepatectomy in the pig

The role of liver blood flow in liver regeneration remains controversial. This study in 17 pigs documents the total hepatic blood flow, and portal and arterial components measured with an electromagnetic flowmeter, the portal pressure, and the cardiac output for 6 days after partial hepatectomy (PH) or sham operation. There was a twofold increase in total flow immediately after PH which rose to three- to fourfold by the second postoperative day. Thereafter values decreased but remained elevated above preoperative values; no similar increase was noted in sham animals. The increase in flow was both absolute as well as relative to the proportion of liver remnant remaining. The portal component increased from 74 +/- 3% preoperatively to 84 +/- 3% (P less than 0.05) on the second postoperative day, and portal pressure was apparently increased. These changes in flow precede the previously documented maximum regeneration response between Days 3 and 4. The factors resulting in the increased flow may be responsible in part, for regeneration.