Effectiveness of Prophylactic Intraperitoneal Mesh Implantation for Prevention of Incisional Hernia in Patients Undergoing Open Abdominal Surgery: A Randomized Clinical Trial.

Importance: Incisional hernia is a frequent complication after open abdominal surgery. Prophylactic mesh implantation in the onlay or sublay position requires dissection of the abdominal wall, potentially leading to wound-associated complications. Objective: To compare the incidence of incisional hernia among patients after prophylactic intraperitoneal mesh implantation with that among patients after standard abdominal closure. Design, Setting, and Participants: An open-label randomized clinical trial was performed in 169 patients undergoing elective open abdominal surgery from January 1, 2011, to February 29, 2014. Follow-up examinations were performed 1 year and 3 years after surgery. The study was conducted at Bern University Hospital, Bern, Switzerland, a referral center that offers the whole spectrum of abdominal surgical interventions. Patients with 2 or more of the following risk factors were included: overweight or obesity, diagnosis of neoplastic disease, male sex, or history of previous laparotomy. Patients were randomly assigned to prophylactic intraperitoneal mesh implantation or standard abdominal closure. Data were analyzed in August 2017. Interventions: Intraperitoneal implantation of a polypropylene-polyvinylidene fluoride mesh with circumferential fixation. Main Outcomes and Measures: The primary end point was the incidence of incisional hernia 3 years after surgery. Secondary end points included mesh-related complications. Results: After the exclusion of 19 patients, 150 patients (81 in the control group and 69 in the mesh group; mean [SD] age, 64.2 [11.1] years; 102 [68.0%] male) were studied. The cumulative incidence of incisional hernia was significantly lower in the mesh group compared with the control group (5 of 69 [7.2%] vs 15 of 81 [18.5%], log-rank test P = .03). Abdominal pain was observed in significantly more patients in the mesh group compared with the control group at 6 weeks (34 of 52 [65%] vs 26 of 59 [44%], P = .04) but not at 12 and 36 months postoperatively. No difference in surgical site infections was observed, but time to complete wound healing of surgical site infection was significantly longer in patients with mesh implantation (median [interquartile range], 8 [6-24] weeks compared with 5 [1-9] weeks; P = .03). Trunk extension was significantly decreased after mesh implantation compared with the control group (mean [SD], 1.73 [0.97] cm vs 2.40 [1.23] cm, P = .009). Conclusions and Relevance: In patients at elevated risk for incisional hernia, prophylactic intraperitoneal mesh implantation reduces the incidence of hernia formation but with increased early postoperative pain and prolonged wound healing of surgical site infection. Trial Registration: ClinicalTrials.gov Identifier: NCT01203553.