Mesenteric lengthening during pouch surgery: technique and outcomes in a tertiary centre.

Anastomotic complications after ileal pouch-anal anastomosis (IPAA) are often associated with excessive tension and poor blood supply. Carrying out a tension-free IPAA might prove difficult in a proportion of cases, especially if mucosectomy and hand-sewn anastomosis are necessary. The aim of the study was to analyse the outcomes of mesenteric lengthening in patients undergoing IPAA in a tertiary centre. Consecutive patients who required mesenteric lengthening during IPAA surgery between 2000 and 2019 were retrospectively included. Short and long-term outcomes were analyzed. Chi square, Fisher's exact test and Wilcoxon rank sum test were used as appropriate. Kaplan-Meier analysis was carried out to report the long-term rate of pouch failure. Some 131 patients (78 UC, three indeterminate colitis, 50 FAP) were included. The need for mesenteric lengthening, due to short mesentery or intraoperative complications, was unpredictable in 15 patients. The rate of surgical complications was 20.6%; eight patients required a reoperation, two of them experienced postoperative pouch ischemia. After a median follow-up time of 9.4 years, the risk of pouch failure in FAP and UC patients was 7.2% and 13% at 10 years. Despite the indication to mucosectomy has been reducing over the years, mesenteric lengthening is still required in a significant proportion of UC and FAP patients, also because of unforeseeable intraoperative conditions necessities.