Should You Use Antimicrobial Dressings On Clean, Uninfected Wounds?
Can Antimicrobial Dressings Lead To Cytotoxicity?
Another reason for the IDSA advising against the use of topical antimicrobials may be the potential to cause cytotoxicity and local adverse effects. In vitro studies in patients with diabetes found silver dressings to be cytotoxic against fibroblasts by significantly modifying the cell morphology.16 This subsequently caused decreased cell proliferation and decreased collagen synthesis. One cell culture study tested 17 wound care products and found products that contained silver or chlorhexidine to be the most cytotoxic.17
While one may note that these studies were in vitro as opposed to in vivo or clinical experimentation, the fact that antimicrobial dressings demonstrated little clinical efficacy in infection prevention and wound healing makes their use more difficult to justify. After reviewing the evidence, it would be difficult to advocate the use of a product with a lack of clinical evidence and the potential to be cytotoxic. Moreover, the increased use of topical antimicrobials may further promote the emergence of bacterial resistance.18-20 While the currently reported clinical incidence of widespread resistance to silver and other topical antimicrobials remains low, the ubiquitous use of topical antimicrobials warrants the monitoring of silver and/or other antimicrobial resistance in wound care.
Does Reducing Bioburden Bolster Wound Healing?
We also need to address the idea that reducing the “bioburden” of chronic skin wounds with antimicrobial dressings enhances healing in chronic wounds. While there is agreement that virtually all wounds are contaminated with microorganisms, some researchers believe the superficial contamination usually has no clinical consequence as the wounds typically show no evidence of infection and heal as expected.6 Others believe that every foot ulcer requires administration of antibiotics, either for therapy or prophylaxis.21
However, despite reasonable arguments from both sides regarding this controversial topic, available studies and clinical practice guidelines from experts do not support this view.3,6,22 While some experimental animal data and studies with burn wounds and skin grafts support this theory behind antimicrobial prophylaxis, most of the published clinical trials indicate antibiotic therapy does not improve the outcome of uninfected lesions.22-24
For example, in a 2012 article in Advances in Skin and Wound Care, authors compared the efficacy of two different silver impregnated dressings, a sodium carboxymethyl cellulose 1.2% ionic silver dressing and a bovine native collagen/ionic silver dressing, and their impact on wound bioburden and wound closure.27 What the study found was that both silver dressings had similar results in the rate of wound healing and little effect on the actual bioburden present in chronic wounds. In addition, neither dressing demonstrated any significant differences in wound closure rate. Although the study involved only a small sample size, the results showed little effect on wound bioburden, which further rouses the debate of using antimicrobial dressings when one can manage such bioburden efficiently through appropriate debridement of the wound bed.27
In all fairness, the management and reduction of bioburden to facilitate wound healing are plausible. However, until such evidence is available from well-designed, methodologically standardized outcome measurement research, there is limited justification for the use of antimicrobial dressings in a clinically clean, non-infected wound when traditional debridement practices are already well established.