Four RCTs were included in the review (n=273 patients; range 48 to 100). Two trials were considered to be of high quality and two trials were deemed to be fair (scores ranged from 6 to 12).
Surgical outcomes: No significant difference was found between J-pouch and side-to-end anastomosis for operative time, blood loss, hospital stay, the development of anastomotic stricture, fistula formation, morbidity and mortality rates. Significant heterogeneity was found for operative time and hospital stay. Clinical values were also presented for these outcomes.
Pressure outcomes: Lower mean postoperative resting pressure was found in the J-pouch group compared with side-to-end anastomosis group, although this was did not reach statistical significance (random effects SMD -1.23, 95% CI -2.47 to -0.01; two RCTs). Evidence of statistical heterogeneity was found (p=0.002). No significant between group difference was found for squeeze pressure; evidence of significant heterogeneity was found.
Volumetric outcomes: No statistical difference was found for volume at which patients first experienced a sensation to defecate (three and 24 months) or the maximal volume tolerated at three and 24 months; evidence of statistical heterogeneity was found.
Functional outcomes: Significantly fewer patients experienced urgency at six months in J-pouch compared with side-to-end anastomosis (RR 0.61, 95% CI 0.39 to 0.96); no evidence of heterogeneity was found (p=0.86). No statistical difference was found for urgency (at 24 months), use of enemas (at six and 24 months), use of pads (at six and 24 months), use of bowel medication (at six and 24 months), incomplete defecation (at six and 24 months), or stool frequency (at six and 24 months).