Gentamicin-Containing Collagen Implant May Reduce Surgical Site Infections After Open Infrainguinal Arterial Revascularization

Background: Deep-space surgical site infections carry significant morbidity and mortality. The evidence for gentamicin-containing collagen implants at reducing surgical site infections in open infrainguinal arterial surgery is limited. This study examined whether gentamicin-containing collagen implants reduces 30-day surgical site infections and their severity following open infrainguinal arterial surgery. Methods: A retrospective observational cohort study that included all patients undergoing infrainguinal arterial bypass or endarterectomy between November 2015 and March 2019 at a single tertiary vascular unit. Patients with contaminated/infected surgical fields, surgical wounds treated with negative pressure therapy, or the usage of antimicrobial implants and dressings other than Collatamp G^Ⓡ (Aralez Pharmaceuticals, Canada) were excluded. Patients with gentamicin-containing collagen implants placed abutting vasculature were compared against patients without gentamicin-containing collagen implants. Outcomes included the rate of surgical site infections and their severity within 30 days after the operation. Results: In 159 procedures (mean age 67.7 years, 74.8% male, 33.3% diabetic, 16.4% chronic renal failure, 25.2% anticoagulated postoperatively, 32.7% with prosthetic implants), 55 (34.6%) procedures received gentamicin-containing collagen implants. There were significantly more males (85.5% vs. 69.2%; P = 0.025), higher rates of obesity (41.8% vs. 26.0%; P = 0.041), and hyperlipidemia (65.5% vs. 49.0%; P = 0.048) in the gentamicin-containing collagen implant group. In total, 6 (3.8%) procedures developed deep-space surgical site infections (1 with gentamicin-containing collagen implant, 5 without) and 13 (8.2%) had severe surgical site infections that required re-intervention (1 with gentamicin-containing collagen implant, 12 without). On logistic regression analysis, the absence of gentamicin-containing collagen implants statistically significantly increased the odds of overall surgical site infections (OR = 2.50; 95% CI 1.01 – 6.19; P = 0.047). There was no statistically significant difference in the odds of deep-space surgical site infections or the severity and need for reintervention of surgical site infections. Conclusions: This is the first study that examined the effect of gentamicin-containing collagen implants on the severity of surgical site infections in vascular surgery. Gentamicin-containing collagen implants may reduce the odds of overall surgical site infections. It did not reduce the odds of deep-space surgical site infections or the severity and reintervention rate of surgical site infections following infrainguinal arterial revascularization. Larger studies are required to achieve adequate power to assess for these outcomes.