Objective: Inguinal incision is the most common vascular surgery incision and is associated with a high rate of surgical site infections (SSIs). The objective of this study was to determine whether intradermal suture leads to a lower SSI rate than metal staples.

Methods: A multicentre, open label, superiority randomised controlled trial was conducted from March 2018 until November 2021 in three Finnish hospitals (ClinicalTrials.gov ID: NCT03468621). Patients with scheduled elective vascular surgery with isolated exposure of the femoral vessels from a longitudinal incision, i.e., femoral endarterectomy, femoral cutdown for endovascular aortic repair, and femoropopliteal or femorofemoral crossover bypass procedure using synthetic graft, were screened for eligibility. Patients were randomised with 1:1 allocation to undergo skin closure with metal staples or continuous intradermal suture. The primary outcome was 30 day SSI rate. SSI was defined according to the US Centers for Disease Control and Prevention (CDC). Secondary outcomes included incision dehiscence and lymphatic leak or seroma.

Results: Three hundred patients aged 54 - 94 years were enrolled (mean age ± standard deviation, 73.4 ± 8.0 years; 217, 72.3% male), with 148 patients randomised to skin closure with intradermal suture and 152 patients to skin closure with metal staples. The SSI rate was 10.1% (15/148) after intradermal suture and 15.8% (24/152) after metal staples (relative risk [RR] 0.64, 95% confidence interval [CI] 0.35 - 1.17; p = .15). The rate of seroma and lymph leak was 12.8% (19/148) and 21.1% (32/152) in the intradermal suture and metal staple groups, respectively (RR 0.6, 95% CI 0.4 - 1.0; p = .060). The rate of inguinal incision complications (infection or dehiscence) was 13.5% (20/148) and 19.7% (30/152) in the intradermal suture and metal staple groups, respectively (RR 0.7, 95% CI 0.4 - 1.2; p = .15).

Conclusion: In patients undergoing elective vascular surgery with primary isolated exposure of the femoral vessels, skin closure with intradermal suture did not reduce the SSI rate compared with the use of metal staples.