Background: Early functional results after complete rectal resection and straight coloanal anastomosis are often characterized by frequent bowel movements, urgency, and varying degrees of stool incontinence. The formation of a colon reservoir improves early and long-term function. We evaluated the feasibility of a novel, modified design of a colon pouch--anal anastomosis in pigs and compared the results with those of pigs with straight coloanal anastomosis and colon J-pouch.
Methods: Complete rectal resection followed by either a straight coloanal anastomosis, a colon J-pouch, or a novel design of a colon pouch was performed in equal numbers in 15 pigs. By transversely closing a longitudinal colotomy, the new, technically simpler pouch is formed. Functional results were assessed during a period of 6 weeks.
Results: All 15 procedures were successful. The novel colon pouch required less surgical time than the colon J-pouch, and the formation of the pouches did not reduce tissue perfusion as assessed by laser Doppler flowmetry. The mean volume of the novel colon pouch was significantly smaller than the volume of the colon J-pouch. All the pigs with the novel colon pouch had normal stool frequency and consistency during a period of 6 weeks. In the group with straight coloanal anastomosis, two pigs had increased frequency of defecation, one pig showed signs of urgency and perianal dermatitis, and three had substantially reduced stool consistency. Of the four pigs with colon J-pouch, three had signs of impaired pouch evacuation and two had reduced stool frequency.
Conclusions: The novel colon pouch is feasible in pigs and technically simpler than the colon J-pouch. These preliminary results indicate that the smaller capacity of this pouch seems sufficient for normal defecation. Its short-term functional results were better than those after reconstruction with a colon J-pouch or a straight coloanal anastomosis.