Transanal ileal pouch-anal anastomosis for inflammatory bowel disease: a systematic review and meta-analysis of short-term outcomes.

Aim: Restorative proctocolectomy with transabdominal ileal pouch-anal anastomosis (abd-IPAA) has become the standard surgical treatment for medically refractory ulcerative colitis (UC). However, it requires a technically difficult distal anorectal dissection and anastomosis due to the bony confines of the deep pelvis. To address these challenges, the transanal IPAA approach (ta-IPAA) was developed. This novel approach may offer increased visibility and range of motion compared with abd-IPAA, although its postoperative benefits remain unclear. The aim of this work was to perform a systematic review and meta-analysis to compare and inform the frequency of postoperative outcomes between ta-IPAA and abd-IPAA for patients with UC.

Method: Several databases were searched from inception until May 2022 for studies reporting postoperative outcomes of patients undergoing ta-IPAA. Reviewers, working independently and in duplicate, evaluated studies for inclusion and graded the risk of bias. Odds ratios (OR), mean differences (MD) and prevalence ratio (PR) and their corresponding 95% confidence intervals (CIs) were calculated using random-effects models. Sensitivity analysis was performed.

Results: Ten retrospective studies comprising 284 patients with ta-IPAA were included. Total mesorectal excision was performed in 61.8% of cases and close rectal dissection in 27.9%. There was no difference in the odds of Clavien-Dindo (CD) I-II complications, CD III-IV and anastomotic leak (OR 0.96, 95% CI 0.27-3.40; OR 1.18, 95% CI 0.65-2.16; OR 1.37, 95% CI 0.58-3.23; respectively) between ta-IPAA and abd-IPAA. The ta-IPAA pooled CD I-II complication rate was 18% (95% CI 5%-35%) and for CD III-IV 10% (95% CI 5%-17%), and the anastomotic leak rate was 6% (95% CI 2%-10%). There were no deaths reported.

Conclusions: This meta-analysis compared the novel ta-IPAA procedure with abd-IPAA and found no difference in postoperative outcomes. While the need for randomized controlled trails and comparison of functional outcomes between both approaches remains, this evidence should assist colorectal surgeons to decide if ta-IPAA is a viable alternative.