Prophylactic Effect of retromuscular mesh during Loop Ileostomy closure On incisional herNia incidence – a multicentre randomized patient- and observer-blind trial (P.E.L.I.O.N Trial).

Abstract Background: Incisional hernia is a frequent complication following loop ileostomy reversal. Incisional hernias are associated with morbidity, loss of health-related quality of life and costs and warrants the investigation of prophylactic measures. Prophylactic mesh implantation at the time of surgical stoma reversal has shown to be a promising and safe method to prevent incisional hernias in this setting. However, the efficacy of this method has not yet been investigated in a large multicentre RCT with adequate external validity. The P.E.L.I.O.N. trial will evaluate the efficacy of prophylactic mesh reinforcement after loop ileostomy closure in decreasing the rate of incisional hernia versus standard closure alone Methods: P.E.L.I.O.N. is a multicentre, prospective, randomized, patient- and observer-blind trial. Patients undergoing loop ileostomy closure will undergo intraoperative 1:1 randomization into either abdominal wall closure with a continuous slowly absorbable suture in small stitch technique without mesh reinforcement (control group) or abdominal wall closure with an additional reinforcement with a retromuscular non-absorbable, macro-pore (pore size ³ 1000 μm or effective porosity >0%) light-weight monofilament or mixed structure mesh. A total of 304 patients (152 per group) will need to be randomised in the study. Based on inclusion and exclusion criteria, 1014 patients are expected to be screened for eligibility in order to recruit the necessary number of patients. Primary endpoint will be the frequency of incisions hernias within 24 months according to the European Hernia Society definition. Secondary endpoints will be the frequency of surgical site occurrences (including surgical site infections, wound seromas and hematomas and enterocutaneous fistulas), postoperative pain, the number of revisions surgeries and health-related quality of life. Safety will be assessed by measuring postoperative complications ≥ grade 3 according to the Dindo-Clavien Classification. Discussion: Depending on the results of the P.E.L.I.O.N. trial prophylactic mesh implantation could become the new standard for loop ileostomy reversal. Trial registration: DRKS00027921, U1111-1273-4657