Clinical use of 0.1% polyhexanide and propylbetaine on acute and hard-to-heal wounds: a literature review.

OBJECTIVE: To summarise the findings on the effect of the clinical use of 0.1% polyhexanide-propylbetaine (PHMB/betaine) solution/gel on acute and hard-to-heal (chronic) wound healing. METHOD: A literature search was conducted in MEDLINE, CINAHL, Embase, Scopus and the CENTRAL Trials Registry of the Cochrane Collaboration. Paired reviewers conducted title and abstract screening and full-text screening to identify experimental, quasi-experimental and observational studies. Study quality and risk of bias were not formally evaluated. RESULTS: A total of 17 studies met the eligibility criteria. The findings from 12 studies indicated that the use of 0.1% PHMB/betaine solution/gel had: a low risk of contact sensitivity; could help debridement during wound cleansing; aided effective wound bed preparation; reduced wound size, odour and exudate; improved pain control; reduced microbial load; and enhanced wound healing. The results of three studies indicated that both 0.1% PHMB and saline solution were effective in reducing bacterial load, while another showed that adding 0.1% PHMB to tie-over dressings had no effect on reducing bacterial loads in wounds. Another study concluded that disinfection and granulation of pressure ulcers with hydrobalance dressing with 0.3% PHMB was faster and more effective than using 0.1% PHMB/betaine. CONCLUSION: The findings of this literature review showed that 0.1% PHMB/betaine solution/gel appeared to be useful and safe for wound cleansing, was effective in removing soft debris and slough from the wound bed, and created a wound environment optimal for healing. Although these actions cannot be attributed solely to this treatment modality, these results do highlight the unique action of this combined product. However, more robust studies are needed to confirm these results.

Effectiveness of a polyhexamethylene biguanide-containing wound cleansing solution using experimental biofilm models.

OBJECTIVE: Antiseptics are widely used in wound management to prevent or treat wound infections, and have been shown to have antibiofilm efficacy. The objective of this study was to assess the effectiveness of a polyhexamethylene biguanide (PHMB)-containing wound cleansing and irrigation solution on model biofilm of pathogens known to cause wound infections compared with a number of other antimicrobial wound cleansing and irrigation solutions. METHOD: Staphylococcus aureus and Pseudomonas aeruginosa single-species biofilms were cultured using microtitre plate and Centers for Disease Control and Prevention (CDC) biofilm reactor methods. Following a 24-hour incubation period, the biofilms were rinsed to remove planktonic microorganisms and then challenged with wound cleansing and irrigation solutions. Following incubation of the biofilms with a variety of concentrations of the test solutions (50%, 75% or 100%) for 20, 30, 40, 50 or 60 minutes, remaining viable organisms from the treated biofilms were quantified. RESULTS: The six antimicrobial wound cleansing and irrigation solutions used were all effective in eradicating Staphylococcus aureus biofilm bacteria in both test models. However, the results were more variable for the more tolerant Pseudomonas aeruginosa biofilm. Only one of the six solutions (sea salt and oxychlorite/NaOCl-containing solution) was able to eradicate Pseudomonas aeruginosa biofilm using the microtitre plate assay. Of the six solutions, three (a solution containing PHMB and poloxamer 188 surfactant, a solution containing hypochlorous acid (HOCl) and a solution containing NaOCl/HOCl) showed increasing levels of eradication of Pseudomonas aeruginosa biofilm microorganisms with increasing concentration and exposure time. Using the CDC biofilm reactor model, all six cleansing and irrigation solutions, except for the solution containing HOCl, were able to eradicate Pseudomonas aeruginosa biofilms such that no viable microorganisms were recovered. CONCLUSION: This study demonstrated that a PHMB-containing wound cleansing and irrigation solution was as effective as other antimicrobial wound irrigation solutions for antibiofilm efficacy. Together with the low toxicity, good safety profile and absence of any reported acquisition of bacterial resistance to PHMB, the antibiofilm effectiveness data support the alignment of this cleansing and irrigation solution with antimicrobial stewardship (AMS) strategies.

Robbing Peter to Pay Paul: Chlorhexidine gluconate demonstrates short-term efficacy and long-term cytotoxicity.

Wound cleansing agents are routine in wound care and preoperative preparation. Antiseptic activity intends to prevent contaminating microbes from establishing an infection while also raising concerns of cytotoxicity and delayed wound healing. We evaluated the cytotoxicity of five clinically used wound cleaning agents (saline, povidone iodine, Dove® and Dial® soaps, and chlorhexidine gluconate [CHG]) using both an ex vivo and in vivo human skin xenograft mouse model, in contrast to classical in vitro models that lack the structural and compositional heterogeneity of human skin. We further established an ex vivo wound contamination model inoculated with ~100 cells of Pseudomonas aeruginosa or Staphylococcus aureus to evaluate antimicrobial efficacy. Scanning electron microscopy and confocal microscopy were used to evaluate phenotypic and spatial characteristics of bacterial cells in wound tissue. CHG significantly reduced metabolic activity of the skin explants, while all treatments except saline affected local cellular viability. CHG cytotoxicity persisted and progressed over 14 days, impairing wound healing in vivo. Within the contamination model, CHG treatment resulted in a significant reduction of P. aeruginosa wound surface counts at 24 h post-treatment. However, this effect was transient and serial application of CHG had no effect on both P. aeruginosa or S. aureus microbial growth. Microscopy revealed that viable cells of P. aeruginosa reside deep within wound tissue post-CHG application, likely serving as a reservoir to re-populate the tissue to a high bioburden. We reveal concerning cytotoxicity and limited antimicrobial activity of CHG in human skin using clinically relevant models, with the ability to resolve spatial localization and temporal dynamics of tissue viability and microbial growth.

IWII Wound Infection in Clinical Practice consensus document: 2022 update.

ABSTRACT: Wound infection is a major challenge for clinicians globally, with accurate and timely identification of wound infection being critical to achieving clinical and cost-effective management, and promotion of healing. This paper presents an overview of the development of the International Wound Infection Institute (IWII)'s 2022 Wound Infection in Clinical Practice consensus document. The updated document summarises current evidence and provides multidisciplinary healthcare providers with effective guidance and support on terminology, paradigms related to biofilm, identification of wound infection, wound cleansing, debridement and antimicrobial stewardship. Integral to the update is revision of wound infection management strategies which are incorporated within the IWII's Wound Infection Continuum (IWII-WIC) and management plan. The aim of the 2022 IWII consensus document update was to provide an accessible and useful clinical resource in at least six languages, incorporating the latest evidence and current best practice for wound infection and prevention. Dissemination techniques for the consensus are discussed and highlighted.

Preoperative contaminated wound management using short-term negative pressure wound therapy with instillation.

BACKGROUND: The short-term application of negative pressure wound therapy with instillation and dwell time (NPWTi-d) enables the delivery of topical wound solutions, the solubilisation of debris and cleansing of the wound bed. The application of NPWTi-d may support the transition of the wound to a more manageable state and minimises the use of more invasive techniques. METHOD: In this case series, we describe the process of applying NPWTi-d early as part of a contaminated wound treatment plan. RESULTS: The case series included 15 patients in the preoperative setting. Wound types included surgical dehiscence, hard-to-heal wounds, heel pressure ulcers, diabetic foot ulcers, a cat bite and an amputation left open. Normal saline or a 0.125% sodium hypochlorite solution were instilled and allowed to dwell for five minutes, followed by 15 minutes of continuous negative pressure at -125mmHg. NPWTi-d was continued for 4-36 hours, or until the operating room became available. After NPWTi-d, we observed a decreased amount of devitalised tissue in the wound bed and reduced oedema and erythema in the periwound area. Patient white blood cells also significantly decreased in all cases after NPWTi-d (p<0.001). CONCLUSION: Short-term use of NPWTi-d may be a useful option for supporting the surgical treatment of contaminated lower extremity wounds.

Hydro-responsive wound dressings for treating hard-to-heal wounds: a narrative review of the clinical evidence.

A break in skin integrity must be repaired as quickly as possible to avoid excess blood and fluid loss, and to minimise the onset of infection. Hard-to-heal wounds, in which the progression of the wound healing response is compromised, present several challenges to healing (for example, the presence of devitalised tissue acting as a physical barrier to healing and as a focus for bacterial contamination with the potential for subsequent infection). The objective of this article is to present, as a narrative review, the clinical evidence supporting the use of a unique hydro-responsive wound dressing (HydroClean, HRWD1, PAUL HARTMANN AG, Germany). The dressing provides a simple treatment option to address a number of clinical challenges clinicians must overcome in order to facilitate wound healing progression. These studies demonstrated that this product supported successful debridement/cleansing of a wide variety of wounds, including hard-to-heal wounds, enabled wound bed preparation, and lead to positive healing outcomes, including in wounds that previously had failed to heal. The simplicity of using HRWD1 as a single dressing can help clinicians overcome a variety of challenges when treating both acute and hard-to-heal wounds, which, with the benefit of proven patient outcomes, could make it an ideal choice for a first-line treatment.

Development and integration of a wound cleansing pathway into clinical practice.

Wound bed preparation has come into sharper focus over the past decade, with strategies identified to improve wound condition. This article focuses on implementing a wound cleansing policy and measuring, through audits, how this change affected rates of wound infection. From 2016 onwards, the Skin Integrity Team at Doncaster and Bassetlaw Teaching Hospitals NHS Foundation Trust took steps to revise and improve wound care practices. This resulted in the introduction of a wound cleansing pathway incorporating a surfactant-based cleanser in place of saline, with subsequent staff training and other changes made to practice. This study details the steps taken to implement the new pathway, which brought a reduction in wound infections of 84.3% between 2017 and 2019.

Wound bed preparation: a case series using polyhexanide and betaine solution and gel-a UK perspective.

OBJECTIVE: The burden of wound care within the NHS is estimated at a cost of £5.3 billion per year and is set to rise annually by 30%. This case series describes the results of using polyhexanide (PHMB) and betaine wound irrigation solution and gels (Prontosan, B.Braun Medical Ltd., UK) across the UK in hard-to-heal (also described as chronic) wounds up to 20 years' duration, with an observation period of greater than one month. Over half of the hard-to-heal wounds were healed and vast improvements to all other wounds were observed. Improvements to wound bed condition were reported as early as two days after commencing initial treatment, with decreases in malodour, exudate, slough and pain reported across the case series. In addition to wound bed improvements, a reduction in dressing change frequency of 55% was observed in hard-to-heal wounds under the new treatment regime.

Negative pressure wound therapy with instillation: International consensus guidelines update.

The use of negative pressure wound therapy with instillation and dwell time (NPWTi-d) has gained wider adoption and interest due in part to the increasing complexity of wounds and patient conditions. Best practices for the use of NPWTi-d have shifted in recent years based on a growing body of evidence and expanded worldwide experience with the technology. To better guide the use of NPWTi-d with all dressing and setting configurations, as well as solutions, there is a need to publish updated international consensus guidelines, which were last produced over 6 years ago. An international, multidisciplinary expert panel of clinicians was convened on 22 to 23 February 2019, to assist in developing current recommendations for best practices of the use of NPWTi-d. Principal aims of the meeting were to update recommendations based on panel members' experience and published results regarding topics such as appropriate application settings, topical wound solution selection, and wound and patient characteristics for the use of NPWTi-d with various dressing types. The final consensus recommendations were derived based on greater than 80% agreement among the panellists. The guidelines in this publication represent further refinement of the recommended parameters originally established for the use of NPWTi-d. The authors thank Karen Beach and Ricardo Martinez for their assistance with manuscript preparation.

The impact of negative-pressure wound therapy with instillation on wounds requiring operative debridement: Pilot randomised, controlled trial.

Presence of bacteria in wounds can delay healing. Addition of a regularly instilled topical solution over the wound during negative-pressure wound therapy (NPWT) may reduce bioburden levels compared with standard NPWT alone. We performed a prospective, randomised, multi-centre, post-market trial to compare effects of NPWT with instillation and dwell of polyhexamethylene biguanide solution vs NPWT without instillation therapy in wounds requiring operative debridement. Results showed a significantly greater mean decrease in total bacterial counts from time of initial surgical debridement to first dressing change in NPWT plus instillation (n = 69) subjects compared with standard NPWT (n = 63) subjects (-0.18 vs 0.6 log10 CFU/g, respectively). There was no significant difference between the groups in the primary endpoint of required inpatient operating room debridements after initial debridement. Time to readiness for wound closure/coverage, proportion of wounds closed, and incidence of wound complications were similar. NPWT subjects had 3.1 times the risk of re-hospitalisation compared with NPWT plus instillation subjects. This study provides a basis for exploring research options to understand the impact of NPWT with instillation on wound healing.

Effects of a surfactant-based gel on acute and chronic paediatric wounds: a panel discussion and case series.

On 20 November 2018, following the International Society for Paediatric Wound Care conference, a closed panel meeting took place in which the use of a surfactant-based gel (PluroGel (PMM), Medline Industries, Illinois, US) in paediatric wound care was discussed. The authors shared their experiences, thoughts, experimental data and clinical results. The panel identified the need for a product that can gently cleanse paediatric wounds and remove devitalised tissue without causing discomfort or skin reactions, as well as potentially promote healing. In adults, PMM has been shown to assist healing by hydrating the wound, controlling exudate and debriding non-viable tissue. Islands of neo-epithelium have also been reported to appear rapidly in different parts of the wound bed. No adverse effects on these proliferating cells have been observed. In vitro data suggest that PMM can remove biofilm, as well as potentially promote healing through cell salvage. The panel, therefore, set out to discuss their experiences of using PMM in the paediatric patients and to establish a consensus on the indications for its use and application in this population. This article will describe the main outcomes of that discussion and present case studies from paediatric patients with a variety of wound types, who were treated with PMM by members of the panel.

Management of wounds in the community: five principles.

The care of any wound in the community requires multidisciplinary working between healthcare professionals. In this article, the authors offer five generalisable principles that colleagues providing community care can apply in order to achieve timely wound healing: (1) assessment and exclusion of disease processes; (2) wound cleansing; (3) timely dressing change; (4) appropriate (dressing choice; and (5) considered antibiotic prescription. High-quality wound care is an essential aspect of healthcare practice but lacks an evidence base and standardised practice at present. The practice and teaching of wound care should be more greatly emphasised in healthcare training for all disciplines.

Equine Practice on Wound Management: Wound Cleansing and Hygiene.

The goal of wound cleansing and care is the control or removal of tissue infection to allow healing in the most functional, cosmetic, fastest, and least expensive manner possible. This is accomplished through the removal of debris and necrotic tissue while reducing the bacterial load via careful use of mechanical techniques and cleaning agents, accepting that some level of tissue trauma will result. Keep in mind that the benefit of a clean wound must be weighed against the trauma inflicted in the process of cleansing. Veterinary health care professionals should take steps to reduce hospital-acquired infections and zoonotic disease transmission.

Evaluation of three experimental in vitro models for the assessment of the mechanical cleansing efficacy of wound irrigation solutions.

The aim of this study was to compare different wound-rinsing solutions to determine differences in the efficiency and to evaluate three different in vitro models for wound cleansing. Different wound-rinsing solutions (physiological saline solution, ringer lactate solution for wound irrigation, water and a solution containing polihexanide and the surfactant undecylenamidopropyl-betain) were applied on standardised test models (one- and three-chamber model, flow-cell method and a biofilm model), each challenged with three different standardised wound test soils. In the one-chamber model saline showed a better effect on decontaminating proteins than the ringer lactate solution. In the flow-cell method, water performed better than physiological saline solution, whereas ringer lactate solution demonstrated the lowest cleansing effect. No obvious superiority between the two electrolyte-containing solutions was detectable in the biofilm model. Unfortunately, it was not possible to assess the protein decontamination qualities of the surfactant-containing solution because of the interference with the protein measurement. The flow-cell method was able to detect differences between different rinse solutions because it works at constant flow mechanics, imitating a wound-rinsing procedure. The three-chamber and the less-pronounced modified one-chamber method as well as the biofilm model had generated inhomogeneous results.

Novel foam dressing using negative pressure wound therapy with instillation to remove thick exudate.

We describe our experience with a novel foam dressing architecture in tandem with negative pressure wound therapy and instillation (NPWTi-d) for removing viscous wound exudate and infectious materials. A retrospective review was conducted of the outcomes of 21 patients who received NPWTi-d using a reticulated open cell foam instillation dressing with through holes (ROCF-CC) designed to facilitate the removal of thick wound exudate and infectious materials. NPWTi-d with ROCF-CC was used to treat large complex chronic wounds with viscous wound exudate that contained substantial areas of devitalised tissue. Debridement was performed as appropriate or available. NPWTi-d with ROCF-CC assisted in loosening, solubilising and detaching viscous exudate, dry fibrin, wet slough and other infectious materials. Percent surface area of black non-viable tissue and yellow fibrinous slough was reduced to ≤ 10% in 18/21 (85·7%) and 12/21 (57·1%) wounds, respectively, after an average of 1-3 applications (3-9 days) of NPWTi-d with ROCF-CC. Preliminary evidence suggests that adjunctive use of NPWTi-d with ROCF-CC may help clean large, complex wounds when complete surgical debridement is not possible or appropriate and/or when areas of slough and non-viable tissue remain present on the wound surface.

Wound cleansing: a key player in the implementation of the TIME paradigm.

The concept of wound bed preparation can be implemented using the TIME paradigm. Chronic wounds are mostly characterised by prolonged inflammation and increased bioburden. Removal of wound biofilm and devitalised tissue, which is an ideal environment for bacterial growth, can help address the I in TIME. Wound cleansing aims to remove contaminants, debris, dressing remnants and superficial slough from the wound. Some wound cleansers contain surfactants, which reduce the surface tension of a liquid, enabling it to spread further over a surface. This article describes how these solutions can be used to debride the wound surface without damaging healthy cells.

[Innovative therapy for leg ulcers: Electrostimulation]. / Une thérapie innovante des ulcères de jambe : l'électrostimulation.

Chronic wounds can take a long time to heal despite appropriate therapy based upon aetiology and use of suitable dressings. The success of electrostimulation is based upon the existence within the skin of the endogenous currents involved in the wound healing process. Where skin continuity is broken by a wound, these electrical potentials are short-circuited, resulting in leakage of electrical current. Woundel(®) therapy is the only such treatment currently available in France and is based on the use of continuous pulsed current that generates an electrical field near the endogenous electrical fields. It utilises a console to deliver the electrical impulses, a dressing electrode and a dispersion electrode. The electrode dressing is left on the wound for 3 days, and venous compression bandaging may be applied to the leg, taking care to leave the connector free. Negative polarity stimulates migration of fibroblasts, resulting in elimination of fibrin. Positive polarity causes keratinocyte migration, which in turn leads to epidermisation. Electrostimulation is of recognised utility in the healing of chronic wounds: it has been assigned a high-level recommendation in the European and American guidelines for the treatment of venous ulcers and bedsores with proof level of A. Further, the analgesic effect of electrostimulation has been demonstrated in several studies. Electrostimulation is already well developed in France among wound specialists, but prospective studies are planned so that it may be used at patients' homes.

Biofilm in wound care.

A biofilm can be described as a microbial colony encased in a polysaccharide matrix which can become attached to a wound surface. This can affect the healing potential of chronic wounds due to the production of destructive enzymes and toxins which can promote a chronic inflammatory state within the wound. Biofilms can be polymicrobial and can result in delayed wound healing and chronic wound infection resistant to antibiotics, leading to prolonged hospitalisation for some patients. There appears to be a correlation between biofilms and non-healing in chronic wounds. It is suggested that biofilms are a major player in the chronicity of wounds. They are a complex concept to diagnose and management needs to be multifactorial.

Comparison of tissue damage, cleansing and cross-contamination potential during wound cleansing via two methods: lavage and negative pressure wound therapy with instillation.

The use of lavage was compared to negative pressure wound therapy (NPWT) with instillation (NPWTi) to assess extent of soft tissue damage, debris removal and environmental cross-contamination susceptibility in three distinct models. Scanning electron microscopy in an ex vivo model showed increased visible tissue trauma from lavage treatment at low and high pressures versus NPWTi, with the degree of trauma relative to the pressure of the irrigant. These results were corroborated in granulating full-thickness excisional swine wounds coated with dextran solution to simulate wound debris. Both low-pressure lavage and NPWTi demonstrated effective cleansing in this model, reducing debris by >90%. However, using three-dimensional photography to evaluate tissue damage by measuring immediate tissue swelling (changes in wound volume and depth) showed significantly greater (P < 0.05) swelling in low-pressure lavage-treated wounds compared with NPWTi-treated wounds. Lastly, bench top wound models were inoculated with fluorescent bacterial particles to assess environmental cross-contamination potential and collected at measured distances after treatment with low-pressure lavage and NPWTi. No evidence of cross-contamination was found with NPWTi, whereas one-half of the particles became 'aerosolised' during low-pressure lavage (P < 0.05). Collectively, these studies demonstrate the effective wound cleansing capabilities of NPWTi without the tissue damage and environmental contamination associated with lavage.

Impact of Interfering Substances on the Bactericidal Efficacy of Different Commercially Available Hypochlorous Acid-Based Wound Irrigation Solutions Commonly Found in South-East Asia.

The high prevalence of chronic wounds is a growing concern. Recently, hypochlorous acid (HOCl)-based solutions were introduced as an alternative antimicrobial for wound cleansing. In this study, we assessed the in vitro bactericidal activities of seven commercially available wound irrigation products commonly found in South-East Asia. The evaluation was conducted using quantitative suspension method, EN 13727 in either low or high protein conditions. Under low protein conditions, four out of the five HOCl products achieved bactericidal activity (≥5 log10 reduction factor; RF) within 2-5 min, and only one product achieved 5 log10 RF at 15 s. None of the HOCl achieved 5 log10 RF under high protein, even after 30 min of exposure time. In contrast, protein interference on the antimicrobial activities of polyhexamethylene biguanide-based product is less pronounced (low protein: 60 s vs. high protein: 2 min to attain ≥5 log10 RF). Octenidine dihydrochloride is the only active not affected by protein interference achieving ≥5 log10 RF within 15 s in both low and high protein conditions. These findings warrant the need to screen antimicrobial wound care products, especially HOCl-based products, in high protein condition to better reflect the antimicrobial activities in wound care.