The role of lactulose in the prevention of bacterial translocation in surgical trauma.

Surgical trauma (ST) is one of the causative factor of bacterial translocation. In this study we investigated the prevention of bacterial translocation with lactulose in a surgical trauma model. The study was designed in 3 experimental groups consisting of 15 rats in each. Group 1 was sham operated controls, group 2 was ST + physiologic saline treated and group 3 was ST + lactulose treated animals. Lactulose and physiologic saline were given by oro-gastric intubation in a dose of 2 ml of 33.5% solution/d and 2 ml/d respectively starting 3 days prior to surgery. Bacterial translocation was investigated 48 hours after the operations. In sham operated controls only 1 bacterial translocation to the mesenteric lymph nodes (MLN) was observed. In the ST + physiologic saline treated group bacterial translocation to the MLN and portal venous blood (PVB) were significantly increased compared with both sham operated controls and the ST + lactulose treated group (p < 0.001). In rats with lactulose treatment the results of caecal bacterial counts showed a significant decrease in the number of gram-negative aerobes and facultative anaerobe bacteria (p < 0.01) and a significant increase in the number of lactobacilli (p < 0.001) compared to the sham operated controls. Measurement of the mucosal height showed a significant increase at the terminal ileum and the caecum compared with the sham operated controls and the surgical trauma+physiologic saline treated group (p < 0.001). We conclude that oral lactulose treatment 3 days prior to the surgical trauma, reduced the incidence of bacterial translocation to the MLN and PVB.