Synthetic mesh versus biological mesh to prevent incisional hernia after loop-ileostomy closure : a randomized feasibility trial

Background: Incisional hernia is a frequent complication after loop-ileostomy closure, rationalizing hernia prevention. Biological meshes have been widely used in contaminated surgical sites instead of synthetic meshes in fear of mesh related complications. However, previous studies on meshes does not support this practice. The aim of Preloop trial was to study the safety and efficacy of synthetic mesh compared to a biological mesh in incisional hernia prevention after loop-ileostomy closure. Methods: The Preloop randomized, feasibility trial was conducted from April 2018 until November 2021 in four hospitals in Finland. The trial enrolled 102 patients with temporary loop-ileostomy after anterior resection for rectal cancer. The study patients were randomized 1:1 to receive either a light-weight synthetic polypropylene mesh (Parietene Macro™, Medtronic) (SM) or a biological mesh (Permacol™, Medtronic) (BM) to the retrorectus space at ileostomy closure. The primary end points were rate of surgical site infections (SSI) at 30-day follow-up and incisional hernia rate during 10 months’ follow-up period. Results: Of 102 patients randomized, 97 received the intended allocation. At 30-day follow-up, 94 (97%) patients were evaluated. In the SM group, 1/46 (2%) had SSI. Uneventful recovery was reported in 38/46 (86%) in SM group. In the BM group, 2/48 (4%) had SSI (p > 0.90) and in 43/48 (90%) uneventful recovery was reported. The mesh was removed from one patient in both groups (p > 0.90). Conclusions: Both a synthetic mesh and biological mesh were safe in terms of SSI after loop-ileostomy closure. Hernia prevention efficacy will be published after the study patients have completed the 10 months’ follow-up.Peer reviewe