Prospective, randomized, multi-institutional clinical trial of a silver alginate dressing to reduce lower extremity vascular surgery wound complications

Objective: Wound complications negatively affect outcomes of lower extremity arterial reconstruction. By way of an investigator initiated clinical trial, we tested the hypothesis that a silver-eluting alginate topical surgical dressing would lower wound complication rates in patients undergoing open arterial procedures in the lower extremity. Methods: The study block-randomized 500 patients at three institutions to standard gauze or silver alginate dressings placed over incisions after leg arterial surgery. This original operating room dressing remained until gross soiling, clinical need to remove, or postoperative day 3, whichever was first. Subsequent care was at the provider's discretion. The primary end point was 30-day wound complication incidence generally based on National Surgical Quality Improvement Program guidelines. Demographic, clinical, quality of life, and economic end points were also collected. Wound closure was at the surgeon's discretion. Results: Participants (72% male) were 84% white, 45% were diabetic, 41% had critical limb ischemia, and 32% had claudication (with aneurysm, bypass revision, other). The overall 30-day wound complication incidence was 30%, with superficial surgical site infection as the most common. In intent-to-treat analysis, silver alginate had no effect on wound complications. Multivariable analysis showed that Coumadin (Bristol-Myers Squibb, Princeton, NJ; odds ratio [OR], 1.72; 95% confidence interval [CI], 1.03-2.87; P = .03), higher body mass index (OR, 1.05; 95% CI, 1.01-1.09; P = .01), and the use of no conduit/material (OR, 0.12; 95% CI, 0.82-3.59; P < .001) were independently associated with wound complications. Conclusions: The incidence of wound complications remains high in contemporary open lower extremity arterial surgery. Under the study conditions, a silver-eluting alginate dressing showed no effect on the incidence of wound complications.