Aim: To investigate the impact of portal inflow on liver remnants in a stable pig model of small-for-size syndrome.
Methods: Twenty pigs underwent mesocaval shunt (MCS) surgery followed by 85%-90% hepatectomy. The control group had no shunt placement; the S1 group had portal flow maintained at an average of 2.0 times the baseline values; and the S2 group had portal flow maintained at an average of 3.2 times the baseline flow. The effect of portal functional competition on the liver remnant was investigated for 48 h postoperatively. Data were presented as mean ± SD. Statistical significance was determined using Student's t test (SPSS, Chicago, IL, United States). Values of P < 0.05 were considered statistically significant.
Results: At 24 h after hepatectomy, biochemical and histological changes were not significantly different between the S1 and S2 groups, but changes in both sets of variables were significantly less than in the control group. At 48 h, biochemical and histological changes were significantly less in the S2 group than in the S1 or control group. The regeneration index was significantly higher in the S2 group than in the S1 group, and was similar to that in the control group. Apoptosis index, serum lipopolysaccharide, and bacterial DNA levels were significantly lower in the S2 group than in the other two groups.
Conclusion: Diversion of portal inflow using MCS reduces portal overflow injury. Excessive diversion of portal inflow inhibits liver regeneration following major hepatectomy. Maintaining portal inflow at an average of 3.2 times above baseline helps promote hypertrophy of the liver remnant and reduce apoptosis.
Keywords: Mesocaval shunt; Portal diversion; Portal flow; Small-for-size syndrome.