The role of hepatic veins in liver operations.

In this report we review the role of the hepatic veins in resective operations of the liver. Emphasis is placed on the distribution of the hepatic veins, their relationship to hepatic arterial and portal venous inflow tracts, and the drainage patterns of hepatic lobules. An extensive review of the older literature has emphasized the necessity to preserve hepatic venous drainage for the various hepatic segments to prevent postoperative liver congestion and injury. Recent experimental and clinical reports have identified the mechanisms through which hepatic vein obstruction can be well tolerated. These mechanisms include interlobar and interlobular collateral development, reversal of blood flow in the portal vein with conversion of the portal vein to an outflow tract, development of extrahepatic collaterals, drainage through the caudate lobe, and increased lymphatic draining to relieve hepatic congestion.