Functional results after “high” coloanal anastomosis and “low” coloanal anastomosis with a colonic J-pouch for rectal carcinoma

The aim of this study was to determine the postoperative function of neorectoanal components using two different types of very low coloanal reconstruction. The two groups of patients assessed were 22 who underwent abdominal rectal resection and stapled “high” coloanal anastomosis without a pouch, being the HCAA-P group; and 34 who underwent anoabdominal rectal resection and “low” coloanal anastomosis with a colonic J-pouch, being the LCAA+P group. Manometric metric examination was performed 1, 3, 6, and 12 months postoperatively, and the patients were also assessed by a questionnaire. The LCAA+P group had remarkably less daily stool frequency and urgency, but there were no significant differences in the other functional parameters. Maximum resting pressure (MRP) was significantly less, while threshold volume (TV) and maximum tolerable volume (MTV) were greater in the LCAA+P group than in the HCAA-P group. The colonic J-pouch compensated for decreased MRP. Thus, when HCAA-P is performed, 3.0 cm of residual rectum with internal anal sphincter may be required, and construction of the pelvic pouch is desirable in low coloanal anastomosis.