Randomized Comparison of Hypochlorous Acid With 5% Sulfamylon Solution as Topical Therapy Following Skin Grafting

Kevin N. Foster, MD, MBA, FACS; K. J. Richey, BSN, RN; J. S. Champagne, MA, RN; M. R. Matthews, MD, FACS


ePlasty. 2019;19(e16) 

In This Article

Abstract and Introduction


Objective: Infections are a serious complication of thermal injury. Excision and grafting have led to a decrease in incidence, but to ensure successful skin grafting, antimicrobial irrigants are frequently utilized to prevent infection. A safe, efficacious, and cost-effective irrigant capable of preventing infections would be a valuable adjunctive therapy. The objectives of this study were to determine whether the test article was noninferior to current therapy in controlling infection and reducing postoperative pain in patients with skin graft.

Methods: Patients with burns requiring skin grafting were randomized to hypochlorous acid or 5% Sulfamylon solution as topical dressings postoperatively. Inclusion criteria included thermal injury 20% or more total body surface area requiring excision and autografting, and age 18 years or more. Exclusion criteria included pregnant females, chlorine sensitivity, and electrical/chemical/cold injuries. The following outcomes were assessed: patient demographics, graft viability, infection, pain score, narcotic usage, adverse events, and cost.

Results: Treatment groups were demographically equivalent. There were no differences in adverse or serious adverse events between the 2 groups. Graft viability and infection rate were equivalent between the 2 groups. In addition, pain scores and narcotic usage were similar. Hypochlorous acid was significantly less expensive than 5% Sulfamylon solution.

Conclusions: Hypochlorous acid demonstrated equivalent efficacy and safety compared with 5% Sulfamylon when used as the postoperative topical dressing for skin grafts. Hypochlorous acid was more cost-effective. This pilot study was limited by its small sample size. However, hypochlorous acid shows promise as a topical wound dressing and further study with larger groups is warranted.


It is estimated that each year in the United States, approximately 500,000 individuals suffer from burns that that require medical attention. Annually, 4000 people die from burn injuries. In total, 40,000 patients with burns are hospitalized each year and 60% (25,000) of these patients are admitted to hospitals with specialized burn units.[1]

Patients with burns, due to the loss of protective skin layer and the immunosuppressive nature of thermal injury, are prone to infection. This is additionally true because most burn centers practice early burn excision and grafting.[2–4] Thus, antimicrobial protection during every step of burn treatment, including surgical interventions, is considered necessary. Most burn centers use topical agents routinely over grafts because of this risk of infection, even in patients with smaller burns.

The causative agents of burn wound infections include bacteria such as Pseudomonas aeruginosa, Klebsiella sp, Staphylococcus sp, Escherichia coli, Proteus mirabilis, Enterococcus spp, Enterobacter spp, Streptococcus sp, and Acinetobacter sp and fungi such as Aspergillus sp, Fusarium sp, Phycomycetes, and Candida sp.[5–8] But because of their immunocompromised status, patients with burns may be susceptible to infections with more unusual microorganisms, even those that normally are not virulent in healthy people. These bacteria might be platonic but often occur as a biofilm.[9] Thus, antimicrobial agents to be used need to have a broad antimicrobial spectrum.

Commonly used topical antimicrobial agents include silver sulfadiazine cream, mafenide lotion, povidone-iodine solution and mafenide acetate 5% solution, Dakin's solution, and other antimicrobial creams, lotions, ointments, and solutions. Bandages, used to cover the grafts, typically must be kept moist for continuous protection and to avoid drying out of the grafts and the wound bed.

Many of these topical agents have adverse effects on healing. Both povidone-iodine and mafenide solution are known to be toxic to mammalian cells and thus might have a detrimental influence on wound healing.[10,11] In addition, absorption of iodine may lead to systemic toxicity,[12,13] whereas mafenide may be painful and lead to metabolic acidosis through inhibition of carbonic anhydrase.[14] Allergic reactions to both materials have been described as well.

Thus, while topical antimicrobial therapy is necessary to protect against infection, agents used do have side effects; however, these are accepted because of the overwhelming need to protect a fresh graft and its wound bed.

Hypochlorous acid (HOCl) is a topical antimicrobial with many desirable characteristics. HOCl is produced in vivo by neutrophils as part of the respiratory burst pathway.[15] This pathway plays a crucial role in intracellular killing of microorganisms by leukocytes.[16–18]

In in vitro studies, HOCl has been shown to rapidly kill gram-positive and gram-negative microorganisms, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus.[19] In additional preclinical studies, the compound was shown to produce greater than log5 kill within 5 minutes of contact against a wide range of pathogens.[20] So far, microbial resistance to HOCl acid has not been identified.

HOCl is thought to have antimicrobial properties via a number of different mechanisms, including the inhibition of bacterial plasma membrane proteins involved in energy transduction:[21] this leads to loss of homeostatic control of ions across the membrane and causes cell swelling. Other hypotheses describe the oxidation of sulfhydryl protein moieties in the bacterial membrane.[22,23]

HOCl has no cellular toxicity to human cells when used in clinically effective dosage: mammalian bodies regulate the levels of HOCl during the inflammatory response using intrinsic antioxidant defense systems by using compounds such taurine and nitrites to neutralize HOCl and to protect against oxidative damage to cells.[24–28]

HOCl has been used extensively for surface disinfection, for the cleaning of endoscopes,[20,29] and as a sanitation method to eliminate pathogenic organisms on foods and surfaces in food service areas.[30]

HOCl irrigation reduces bacterial counts in chronic open wounds more effectively than saline. HOCl irrigation in chronic wounds also likely results in fewer wound complications than saline alone.[31]

Vashe Wound Therapy contains HOCl; it was used for this study at nominal concentrations of 150 to 180 ppm. The compound is the same as the one used in the leukocyte-intracellular-killing process. Thus, Vashe Wound Therapy mimics one of the body's main ways of killing microorganisms.

We hypothesize that Vashe Wound Therapy may provide a safe, efficacious, and cost-effective alternative in burn wound management and that Vashe Wound Therapy may also reduce pain at the burn wound site.