The Mathematical Relationship Between Blood Loss And Hepatic Vascular Occlusion Techniques In Hepatectomy

Objective:To investigate the mathematical relationship between blood loss and hepatic vascular occlusion techniques in hepatectomy.Methods:85rabbits were randomly divided into5groups namely A (n=20), B (n=20), C (n=20), D (n=20), and E (n=5). Group A, B, and C underwent hepatectomy with Pringle maneuver, hemihepatic vascular occlusion, or hemihepatic vascular occlusion with infrahepatic inferior vena cava clamping, respectively. Group D was the blank control with no vascular occlusion in hepatectomy. Pressure of related blood vessels was tested selectively before and after clamping, including hepatic artery pressure, portal vein pressure, central venous pressure (CVP) and inferior vena cava (IVCP). The blood loss was estimated for10minutes during hepatectomy. After stopping bleeding, we monitored the rabbits for1hour post-operatively. Group E was kept for observation separately after infrahepatic inferior vena cava ligation without hepatectomy.Results:1. CVP and IVCP were significantly positive liner correlated in A, B, C and D group.2. CVP decreased significantly after occlusion in Group A and C(decreased by0.95mmHg and1.88mmHg respectively, p<0.05), but not in group B (p=0.204).3. Blood loss in Group A, B and C(C<A<B) were significantly lower compared to Group D(4,27ml,5.11ml,3.63ml vs.27.11ml, p<0.05; p<0.05among group A, B, and C).4. Blood loss and ICVP were significantly positive correlated in Group A, B, and C. Blood loss and pressure of inferior vena cava, hepatic artery, portal vein were significantly positive correlated in Group D.5. Rabbits in group E remained stable post-operation, and no major complications occurred.Conclusions:1. CVP and IVCP were significantly positive liner correlated and remained after occlusion.2. B Blood loss was correlated with IVCP after inflow vascular control.3. Hemihepatic vascular occlusion with infrahepatic IVC clamping is safe and effective in lowering CVP and IVCP, thus reducing blood loss during hepatectomy.