Cultured
skin substitutes (CSS) have become a useful adjunctive treatment for closure of
burn wounds, but CSS are avascular and remain susceptible to microbial destruction longer than split-thickness skin grafts. Irrigation of CSS grafted to
burn wounds with a topical antimicrobial
solution (TAS) has been shown to promote engraftment of CSS, but TAS usage has potential limitations.
Acticoat Burn Dressing (
Acticoat; Westaim Biomedical, Exeter, NH) is a
silver-coated barrier dressing reported to exhibit antimicrobial activity and to reduce
infection in partial-thickness and full-thickness
wounds. This study evaluated the cytotoxicity of
Acticoat with CSS and the efficacy of
Acticoat for the management of microbial contamination in CSS grafted to full-thickness
wounds in athymic mice. The cytotoxicity of
Acticoat was assessed in preliminary studies after 1 week of exposure to CSS during in vitro maturation or healing on
wounds in athymic mice. Histologies were analyzed and cellular viability in the CSS was determined by MTT conversion on days 0, 1, and 7 of
Acticoat exposure. At 1, 2, 3, and 4 weeks after grafting,
wounds were traced, and areas of healing CSS were calculated by image analysis. At 4 weeks,
wound biopsies were evaluated and scored for engraftment of human cells. In a subsequent study,
wounds were inoculated with strain SBI-N of Pseudomonas aeruginosa at 1 x 10(5) cfu/
wound before the application of CSS or inoculated onto the surface of
Acticoat. At 4 weeks, swab cultures were collected from the surface of CSS and scored for the presence of SBI-N. Statistical significance was accepted at the 95% confidence level (P <.05). The data show that exposure in vitro of CSS to
Acticoat was cytotoxic within 1 day, but 1 week of exposure in vivo did not injure CSS or inhibit wound healing. Contaminated
wounds treated with
Acticoat healed similarly to control treatments, with comparable rates of engraftment, and detection of SBI-N on the surface of only one graft. No SBI-N was detected on CSS after inoculation onto the surface of
Acticoat. These results suggest that
Acticoat may be suitable as a protective dressing to reduce environmental contamination of CSS, if used in conjunction with additional antimicrobials to control organisms present in the
wound.