Article originally featured on WoundSource
Treatment of chronic and complex wounds complicated by biofilm formed by pathogens remains a tremendous challenge for the health care industry. Recent increases in infections mediated by drug-resistant bacterial and fungal pathogens highlight the need for new antimicrobial therapies.1 The application of topical agents with antimicrobial and antiseptic properties is gaining traction as an alternative to antibiotic prescriptions.
Selection of a Topical Wound Cleansing Agent
When selecting topical cleansing agents, clinicians must consider agents that provide antisepsis but are not cytotoxic to healthy tissue within and around the wound. Tap water alone is not a suitable cleansing agent because it can be cytotoxic to skin fibroblasts given its alkaline pH, hypotonicity, and the presence of cytotoxic trace elements. Cleansing agents are more effective because many can reduce the bacterial load or help eliminate biofilm activity within the wound.2 Proper cleansing can be incorporated during dressing changes as part of a comprehensive wound bed preparation strategy.
Several topical cleansing agents to consider for wound be preparation include:
Hypochlorite solution: Recently, newer antiseptic agents have been used more frequently in clinical settings to cleanse wounds. These agents are chlorine-based and chlorine-releasing agents, including sodium hypochlorite. This cleansing agent has an advantage over other popular cleansers because it displays no remanence effect, thus lowering the number of microorganisms that could multiply after an incubation period. It also has very low cytotoxicity.3 These compounds can be cytotoxic at high concentrations, and they may have a negative effect on the survival and differentiation of stem cells of the apical papilla.4
Hypochlorous acid: Hypochlorous acid is another chlorine-based cleanser, and it also occurs naturally in humans. The mechanism of action for these cleansing agents is their strong oxidative properties, which lead to microbial amino acid and phospholipid degradation and hydrolysis. Hypochlorous acid works efficiently against vegetative bacteria, bacterial spores, and aspergilli.3 Hypochlorous acid as a bactericide can be up to 80 times more powerful than hypochlorite solutions.5
Polyhexanide: Polyhexanide is another common irrigation and cleansing solution. It is highly effective at removing debris and slough from the wound and disrupting and removing biofilm. The use of polyhexanide can improve the wound bed conditions, such as reduced exudate, malodor, and slough.6 Polyhexanide also has the ability to penetrate difficult-to-remove coatings and lift bacteria, biofilm, and debris from the wound and suspend them in the solution to prevent recontamination. It impacts a broad spectrum of bacteria, viruses, and fungi, with no evidence of toxicity or resistance.7
Octenidine: Similar to polyhexanide, octenidine-based antiseptics display high antimicrobial activity against biofilms formed by Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa strains. As a positively charged material, octenidine adheres to the negatively charged cell walls of microorganisms, attacks enzymatic systems, and leads to leakage of the cytoplasmic membrane and microbial cell death. It demonstrates broad-spectrum antimicrobial properties, including against gram-positive and gram-negative bacteria, chlamydiae, and fungi.3
Acetic acid: In general, an acidic wound environment supports control of infection, toxicity of bacterial metabolites, protease activity inhibition, release of oxygen, and epithelialization and angiogenesis. This cleanser can be effective against gram-positive and gram-negative organisms, particularly Pseudomonas aeruginosa. It can also help to reduce odor from the wound.8 It can, however, be cytotoxic, and it is generally recommended only for initial cleansing of very dirty or odorous wounds before switching to an agent without cytotoxic properties.
Biofilm-Based Wound Care
Biofilm-based wound care differs from local infection management in its aggressive step-up/step-down approach of multiple therapies, including cleansing, to address underlying etiologies and bacterial burden. The step-up/step-down biofilm-based wound care strategy incorporates multiple therapies, including9:
Repeated debridement to physically disrupt biofilm communities and expose the microorganisms to make them vulnerable to topical antiseptics.
Cleansing with an appropriate agent to remove residual debris and antimicrobial intervention against exposed bacteria and residual biofilm.
Use of an antimicrobial agent with proven effects against mature biofilms in clinical practice.
Conclusion As it becomes more crucial to reserve antibiotic use whenever clinically possible, antiseptic and antimicrobial cleansers will be increasingly important to manage bioburden and to control and prevent wound infections.
1. Antonelli A, Giovannini L, Baccani I, Guiliani V, Pace R, Rossolini GM. In vitro antimicrobial activity of the decontaminant HybenX® compared to chlorhexidine and sodium hypochlorite against common bacterial and yest pathogens. Antibiotics. 2019;8:188.
2. Murphy C, Atkin L, Swanson T, et al. Defying hard-to-heal wounds with an early antibiofilm intervention strategy: wound hygiene. J Wound Care. 2020;29(3b):S1-S26.
3. Krasowski G, Junka A, Paleczny J, et al. In vitro evaluation of polyhexanide, octenidine, and NaClO/HClO-based antiseptics against biofilm formed by wound pathogens. Membranes (Basel). 2021;11(1):62. https://doi.org/10.3390/membranes1100062/.
4. Coaguila-Llerent H, Rodrigues EM, Tanomaru-Filho M, Guerreiro-Tanomaru JM, Faria G. Effects of calcium hypochlorite and octenidine hydrochloride on L929 and human periodontal ligament cells. Braz Dent J. 2019;30(3):213-219. htttp://dx.doi.org/10.1590/0103-6440201902280.
5. Hydroinstruments. Basic chemistry of chlorination. 2010. http://www.hydroinstruments.com/files/Basic%20Chemistry%20of%20Chlorinat.... Accessed March 1, 2021.
6. Atkin L, Stephenson J, Cooper DM. Wound bed preparation: a case series using polyhexanide and betaine solution and gel-a UK perspective. J Wound Care. 2020;29(7):380-386.
7. Wolcott R, Fletcher J. The role of wound cleansing in the management of wounds. Wounds Int. 2014;1(1):25-31.
8. Nagoba B, et al. Acidic environment and wound healing: a review. Wounds. 2015;27(1):5-11.
9. Dowsett C, Bellingeri A, Carville K, Gaten A, Woo K. A route to more effective infection management: the infection management pathway. Wounds Int. 2020;11(3):50-57.