Silver Antimicrobial Dressings in Wound Management: A Comparison of Antibacterial, Physical, and Chemical Characteristics

Disclosure: All authors are paid employees of ConvaTec Ltd, Flintshire, United Kingdom. Until recently, local wound infection has been a challenge with few management options. However, the advent of advanced wound dressings containing topical antimicrobial agents, such as silver, has provided a new approach to the control of wound pathogens. Silver has proven antimicrobial activity that includes antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Its role as an antimicrobial agent is particularly attractive, as it has a broad spectrum of antimicrobial activity , 6 with minimal toxicity toward mammalian cells at low concentrations and has a less likely tendency than antibiotics to induce resistance due to its activity at multiple bacterial target sites. Topical creams or solutions containing silver (eg, silver sulfadiazine) have long been used as a mainstay of wound management in burn patients who are especially susceptible to infection. H o w e v e r , disadvantages to their use include staining the skin and toxicity. In addition, the need for frequent removal and reapplication of silver sulfadiazine due to the development of pseudoeschar is both time consuming for professionals and painful for p a t i e n t s . , 9 A range of antimicrobial dressings containing silver either incorporated within or applied to the dressing are now available for clinical use. 0 This new class of dressings is designed to provide the antimicrobial activity of topical silver in a more convenient application. However, the dressings themselves differ considerably in the nature of their silver content and in their physical and chemical p r o p e r t i e s . This study compares the i n v i t r o a n t i b a c t e r i a l activity of 7 such dressings against 2 common wound pathogens, Staphylococcus aureus a n d Pseudomonas aeruginosa. The correlation between silver content and/or silver release from each dressing and its antibacterial effect is examined, and factors relating to the provision of an optimal environment for wound healing are compared to provide a basis for an overall assessment of the clinically valuable properties of each dressing.