Comparison of anastomotic microcirculation in coloanal J-pouches versus straight and side-to-end coloanal reconstruction: an experimental study in the pig

Several studies have shown a lower rate of anastomotic leakages in patients with coloanal J-pouch reconstruction than in those with straight coloanal anastomosis following anterior resection of the rectum. This study investigated whether this difference is due to a better anastomotic microcirculation. Thirty-two healthy, adult Göttinger mini-pigs underwent anterior rectal resection. They were subsequently randomized to following four groups (eight pigs per group): straight end-to-end, side-to-end, small pouch (4 cm), and large pouch (8 cm) coloanal anastomosis. Bowel perfusion was measured before and after vessel ligature at predefined locations using laser Doppler flowmetry. After completion of the anastomosis microcirculation was investigated 1 cm above, below, and directly at the anastomotic site. Following vessel ligature there was a 25% drop in blood flow. After completion of the anastomosis there was a further decrease of 25% in the distal segment, while no changes were observed above the anastomosis. There were no statistical differences either before or after completion of the anastomosis between the various groups. It is concluded that anastomotic blood flow does not depend on the type of coloanal reconstruction in healthy pigs.