Background:
Major lower limb vascular surgeries may result in severe, remote injury of the gastrointestinal system, which has high mortality rates. Postconditioning is a technique with potential capability of reducing remote gastrointestinal complications. Our aim was to assess the remote macro- and micro-hemodynamic changes of the small intestine following an infrarenal aortic occlusion and to evaluate the effects of postconditioning on these alterations.

Material and Methods:
Male Wistar rats underwent 3 hours of infrarenal aortic occlusion followed by 4 hours of reperfusion. In one group, postconditioning was applied. During the experiment blood pressure, superior mesenteric artery flow and mucosal microcirculation of duodenum, jejunum and ileum were assessed. At the end of the experiment, samples were taken from each intestinal segment for histological examinations.

Result:
Superior mesenteric artery flow, as well as segmental small bowel microcirculation showed significant impairment in the IR group in contrast to the sham-operated group, (flow: p=0.012; microcirculation(duodenum): p=0.012; microcirculation(jejunum): p=0.008; microcirculation(ileum): p=0.002), while histological damage was significantly elevated. Strong negative correlation was found between microcirculatory values and histological damage (r= - 0.911, p<0.001). Postconditioning was able to limit flow reduction in all small bowel segments and in the superior mesenteric artery (flow: p=0.009; microcirculation(duodenum): p=0.009; microcirculation(jejunum): p<0,001; microcirculation(ileum): p<0.001), and was able to significantly reduce histological damage.

Conclusion:
Microcirculatory impairment might be responsible for remote intestinal injury following infrarenal aortic occlusion. Postconditioning was able to reduce this remote intestinal damage.