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Abstract: Wounds that become infected can lead to devastating consequences for patients, resulting in substantially increased healthcare costs. Bacterial barrier dressings are a first line of protection against developing wound infections. Most bacterial barrier dressings contain microbicidal chemicals (eg, silver ions, iodine, chlorhexidine) that are released from the dressings, which can be toxic to wound cells. A need exists for cost effective bacterial barrier dressings that absorb wound exudate and do not release toxic materials into the wound or increase the risk for developing bacterial resistance to the microbicidal chemical. The present study reports the development and properties of a novel bacterial barrier dressing that meets these needs. Methods. A high molecular weight (~250 k Daltons) polymer containing a high density of quaternary amines (polydiallyldimethylammonium chloride [polyDADMAC]) was permanently bonded onto cellulose fibers (gauze). Microbicidal and mammalian cell cytotoxicity tests were conducted using standard methods. Development of bacterial resistance to the microbicidal fibers was assessed over 10 passages. Results. The polyquat-treated bacterial barrier gauze dressing (BIOGUARD [BBD]) had high microbicidal activity even in the presence of proteinaceous fluid against a wide range of Gram-positive and Gram-negative bacteria. The BBD dressing passed all mammalian cell toxicity tests due to the non-leaching of the bactericidal polymer. Furthermore, the BBD dressing did not demonstrate any ability to induce bacterial resistance in selection vector testing. Conclusion. This novel dressing featuring a bound microbicide offers another choice for wound caregivers to provide patients with an antimicrobial barrier dressing safe enough for prophylactic use to protect against wound infections.

  Wound infections occur in both acute and chronic wounds, and lead to substantial patient morbidity, mortality, and increased expense. The ideal treatment for any wound has been well articulated in the principles of wound bed preparation and management, and involves creating the optimal environment for the wound to re-epithelialize.¹ Factors to help ensure optimal wound healing include wound bed preparation (proper debridement of compromised tissue), proper moisture management, and the exclusion of exogenous influences that would retard healing, such as bacteria that can cause infection or agents that could impede wound healing.²

  A common strategy to protect wounds from bacterial colonization is to use a bacterial barrier dressing, which can be physical barriers such as films (commonly polyurethanes) that are gas-permeable but have the ability to block liquids, or moisture-permeable dressings containing antiseptics that block bacterial transmission by killing bacteria. The latter class is largely dominated by treated gauze products, alginates, and other dressings utilizing antiseptic molecules (ie, silver ions, polyhexamethylene biguanide [PHMB], iodine, or chlorhexidine) that are released from the dressings into the wound bed. These released broad-spectrum agents are not selective for bacteria (like antibiotics that affect specific bacterial target sites), and each agent can show some level of toxicity toward mammalian cells in the wound bed.³

  Silver products have the largest market share of antimicrobial products and comprise the bulk of bacterial barrier dressings. Concerns exist regarding the cytotoxic effects of silver on cultured cells.