Effect of Mechanical Debridement and Irrigation With Hypochlorous Acid Wound Management Solution on Methicillin-resistant Staphylococcus aureus Contamination and Healing Deep Dermal Wounds in a Porcine Model

Abstract

Wound cleansing is an important component of wound management. This study was conducted to examine the effect of a wound management solution (WMS) containing hypochlorous acid (HOCl) on methicillin-resistant Staphylococcus aureus (MRSA) and healing when used in conjunction with debridement. Nineteen (19) deep reticular dermal wounds (22 mm × 22 mm × 3 mm deep) were created on the paravertebral and thoracic areas of 3 female pigs using a specialized electrokeratome. Wounds were separated by at least 5 cm to 7 cm of unwounded skin and inoculated with MRSA. After 72 hours, all wounds were debrided with a curette and irrigated with either the WMS or sterile saline solution twice per day from day 0 to day 4. Wounds then were irrigated once a day until the completion of the study (day 11). Wound tissue specimens were taken using punch biopsy for microbiological and histological analysis on days 4, 8, and 11 post treatment. Percent of wound epithelialized, epithelial thickness (cell layers µm), white cell infiltrate (1 = absent, 2 = mild, 3 = moderate, 4 = marked, 5 = exuberant), and percent of granulation tissue formation were calculated and assessed. Microbiology and histology results were analyzed for significant differences between treatments and among assessment days using one-way analysis of variance and student t-tests. A P value ≤ .05 was considered significant. The WMS effected a bacterial reduction (P ≤ .05) of more than 2.74 ± 0.43 and 1.03 ± 0.22 Log CFU/g in all assessment days compared with baseline before and after debridement, respectively. Percent epithelialization was significantly different between treatments on day 8, only 78.3% and 67.8% for HOCl and saline, respectively (P ≤ .05). No significant differences between treatments were observed for epithelial thickness or granulation tissue formation. The combination of debridement and HOCl wound irrigation can significantly reduce MRSA contamination and facilitate the healing process compared to saline irrigation. Clinical studies are needed to confirm these results.