Successful modulation of portal inflow by somatostatin in a porcine model of subtotal hepatectomy

Abstract

Aims: To assess the intraoperative effects of somatostatin (SM) on splanchnic hemodynamic parameters in two porcine models of extended hepatectomy. Methods: Twenty female pigs underwent surgery and were divided in 3 groups: 7 animals underwent 70% hepatectomy (H70 group), 7 underwent 90% (subtotal) hepatectomy (H90 group), and 6 underwent sham laparotomy (control group). The variations of splanchnic hemodynamic parameters (portal vein flow, PVF; hepatic artery flow, HAF; portal vein pressure, PVP; inferior vena cava pressure, IVCP; and hepatic venous pressure gradient, HVPG [defined as IVCP-PVP]) were assessed before and after infusion of SM. Flow values were normalized to the liver remnant weight. Results: The mean body and liver weights were 28,600 and 784 grams, respectively (liver-to-body ratio = 2.8%). The mean weights of the excised livers were 600 and 711 grams (71.3% and 88.6% of the whole liver), and the liver remant-to-body ratios were 0.77% and 0.33% in the H70 and in the H90 groups, respectively. A significant increase in PVF was observed after both 70% and 90% hepatectomy (+67%, p = 0.031 and +278%, p = 0.016, respectively), while HVPG significantly increased only after 90% hepatectomy (from 5.5 to 13 mmHg, p = 0.004). After intraoperative infusion of SM, PVF decreased in all 3 groups (−13% in the control group, p = 0.062; −12% in the H70 group, p = 0.031; −17% in the H90 group, p = 0.016), while HVPG significantly decreased and returned to normal value in the H90 group only (from 14.3 to 7.7 mmHg, p = 0.047). No significant changes in HAF were observed after SM infusion. Conclusions: Somatostatin reduces portal inflow and restores a normal HVPG below critical values, without changes in HAF in a porcine model of small-for-size syndrome.