Laboratory Research
Cutaneous wounds often require cleansing with topicals that aid in reduction of wound debris and maintenance of wound pH conducive to cutaneous healing potential. Hypochlorous acid (HOCl) is used in a wound cleansing solution that is formulated to have a pH comparable to normal human skin. Reduction in wound debris is thought to occur in part from its ability to create an acidic wound environment. Other available products are also used as topical cleansers but are highly alkaline and therefore may be less conducive to re-epithelialization. Here, we investigated an HOCl-based wound solution (HOCL WS) to determine whether application to a burn wound would alter the pH of the solution to become more alkaline or retain acidity < 6.0.
Methods:
Female Yorkshire swine (n=4) were anesthetized, sedated, and subjected to a full thickness cutaneous burn with an aluminum branding iron. Burns were dressed with 1% silver sulfadiazine cream. Animals received fluid resuscitation and supportive care throughout the experiment and were monitored for 24 hours post-injury. After 24 hours, wounds were debrided, and HOCL WS (0.033% HOCl)-soaked gauze was applied to debrided burns or adjacent uninjured skin for 20 minutes. The soaking solution was then extracted and measured in triplicate for pH using a pH meter.
Results:
The pH of HOCl WS alone did not change when combined with sterile gauze (5.22±0.02 vs 5.34±0.06; p=0.83) in the absence of wound exposure. After application to both normal skin and burn wounds, the pH of solution decreased, indicating a shift towards higher acidity (4.26±0.28 and 4.16±0.30, respectively; p< 0.0001). There was no difference in pH between normal skin- and burned skin-soaked sites (p=0.89).
Discussion:
HOCl WS did not become alkaline after application in an acute swine burn model. Given that chronic wounds are typically alkaline and that acidic pHs may aid in wound healing, this on-the-market HOCl WS may be an effective agent for cleansing chronic wounds. Human studies in chronic wounds are underway to explore the pH dynamics of HOCl WS. These data will be compared to common wound solutions that are inherently alkaline, such as those containing chlorhexidine or sodium hypochlorite in future studies.