Abdominal incision defect following AAA-surgery (AIDA): 2-year results of prophylactic onlay-mesh augmentation in a multicentre, double-blind, randomised controlled trial

Abstract

The reported incidence of incisional hernia following repair of abdominal aortic aneurysm (AAA) via midline laparotomy is up to 69%. This prospective, multicenter, double-blind, randomised controlled trial was conducted at eleven hospitals in Germany. Patients aged 18 years or older undergoing elective AAA-repair via midline incision were randomly assigned using a computer-generated randomisation sequence to one of three groups for fascial closure: with long-term absorbable suture (MonoPlus^®, group I), long-term absorbable suture and onlay mesh reinforcement (group II) or extra long-term absorbable suture (MonoMax^®, group III). The primary endpoint was the incidence of incisional hernia within 24 months of follow-up, analysed by intention to treat. Physicians conducting the postoperative visits and the patients were blinded. Between February 2011 and July 2013, 104 patients (69.8 ± 7.7 years) were randomised, 99 of them received a study intervention. The rate of incisional hernia within 24 months was not significantly reduced with onlay mesh augmentation compared to primary suture (p = 0.290). Furthermore, the rate of incisional hernia did not differ significantly between fascial closure with slow and extra long-term absorbable suture (p = 0.111). Serious adverse events related to study intervention occurred in five patients (5.1%) from treatment groups II and III. Wound healing disorders were more frequently seen after onlay mesh implantation on the day of discharge (p = 0.010) and three (p = 0.009) and six (p = 0.023) months postoperatively. The existing evidence on prophylactic mesh augmentation in patients undergoing AAA-repair via midline laparotomy probably needs critical review. As the implementation of new RCTs is considered difficult due to the increasing number of endovascular AAA treated, registry studies could help to collect and evaluate data in cases of open AAA-repair. Comparisons between prophylactic mesh implantation and the small bite technique are also required. Trial registration: ClinicalTrials.gov Identifier: NCT01353443. Funding Sources: Aesculap AG, Tuttlingen, Germany.

Keywords: Abdominal; Aortic aneurysm; Fascial suture closure; Incisional hernia; Onlay mesh; Randomised controlled trial.

Fig. 1

CONSORT flow diagram of the trial

Fig. 2

Kaplan–Meier curve for the probability of an event-free time. Comparison of the three treatment groups MonoPlus (group I), Monoplus and Olay Mesh Reinforcement (group II) and MonoMax (group III) based on the primary event “incision hernia within 24 months”

Fig. 3

Kaplan–Meier curve for the probability of an event-free time. Comparison of onlay mesh reinforcement (group II) versus no onlay mesh reinforcement (group I and III) a and of MonoPlus (group I and II) versus MonoMax (group III) b in regards to the secondary event “incision hernia within 12 months”