Histological basis of the liver hanging maneuver

Background  Liver hanging maneuver (LHM) consists in passing a tape between the retrohepatic inferior vena cava (RHIVC) and the liver to perform various kinds of hepatectomies. LHM is a well-known procedure but its histological basis remains poorly documented. Methods  Ten anatomical specimens comprising RHIVC, and surrounding hepatic parenchyma were studied after conventional staining and immunohistochemistry with specific antibody for alpha smooth muscle actin. Results  RHIVC wall structure consists of a thick muscular layer of longitudinal smooth muscle fibers and a peripheral loose connective tissue without smooth muscle fibers adherent to the liver parenchyma. This loose connective tissue between the liver and the RHIVC is the avascular plane for the passage of the clamp during LHM. Conclusion  The histological structure of the RHIVC does not seem to have any special hemostatic property. The low bleeding rate during LHM can be only explained by the very low density of RHIVC afferent veins.