I Philip Bowler

Bio: I Philip Bowler is an academic researcher from Center for Global Development. The author has contributed to research in topics: Wound care. The author has an hindex of 1, co-authored 1 publications receiving 8 citations.

Development of a next-generation antimicrobial wound dressing.

Abstract: Delayed wound healing due to infection is a burden on healthcare systems, and the patient and caregiver alike. An emerging factor in infection and delayed healing is the presence development of biofilm in wounds. Biofilm is communities of microorganisms, protected by an extracellular matrix of slime in the wound, which can tolerate host defences and applied antimicrobials such as antibiotics or antimicrobial dressings. A growing evidence base exists suggesting that biofilm exists in a majority of chronic wounds, and can be a precursor to infection while causing delayed healing itself. In vivo models have demonstrated that the inflammatory, granulation and epithelialization processes of normal wound healing are impaired by biofilm presence. The challenge in the development of a new antimicrobial wound dressing was to make standard antimicrobial agents more effective against biofilm, and this was answered following extensive biofilm research and testing. A combination of metal chelator, surfactant and pH control displayed highly synergistic anti-biofilm action with 1.2% ionic silver in a carboxymethylcellulose dressing. Its effectiveness was challenged and proven in complex in vitro and in vivo wound biofilm models, followed by clinical safety and performance demonstrations in a 42-patient study and 113 clinical evaluations. Post-market surveillance was conducted on the commercially available dressing, and in a 112-case evaluation, the dressing was shown to effectively manage exudate and suspected biofilm while shifting difficult-to-heal wounds onto healing trajectories, after an average of 4 weeks of new dressing use in otherwise standard wound care protocols. This was accompanied by a low frequency of dressing related adverse events. In a second evaluation, clinical signs of infection and wound dimension data, before and after the evaluations, were also available. Following an average of 5.4 weeks of dressing use, all signs of clinical infection were reduced, from an average frequency of 36% to 21%. An average of 62% wound size reduction was achieved, with 90% of wounds reducing in size and 10 wounds healing completely. The new clinical evidence for this next-generation antimicrobial wound dressing suggests it is safe and effective at managing exudate, infection and biofilm, while it can shift established, stubborn wounds onto healing trajectories. The scientific rationale for this new dressing technology is supported by in vitro and in vivo evidence, so now further comparative, randomized and outcome-based clinical studies are required to fully understand the clinical and economic benefits this new dressing technology can bring.

Non-antibiotic antimicrobial interventions and antimicrobial stewardship in wound care

Abstract: Control of wound infection today relies largely on antibiotics, but the continual emergence of antibiotic-resistant microorganisms threatens a return to the pre-antibiotic era when physicians used antiseptics to prevent and manage infection. Some of those antiseptics are still used today, and others have become available. A diverse variety of non-antibiotic antimicrobial interventions are found on modern formularies. Unlike the mode of action of antibiotics, which affect specific cellular target sites of pathogens, many non-antibiotic antimicrobials affect multiple cellular target sites in a non-specific way. Although this reduces the likelihood of selecting for resistant strains of microorganisms, some have emerged and cross-resistance between antibiotics and antiseptics has been detected. With the prospect of a post-antibiotic era looming, ways to maintain and extend our antimicrobial armamentarium must be found. In this narrative review, current and emerging non-antibiotic antimicrobial strategies will...

Mode of action of poloxamer-based surfactants in wound care and efficacy on biofilms.

Abstract: Surfactants are widely used as detergents, emulsifiers, wetting agents, foaming agents, and dispersants in both the food and oil industry. Their use in a clinical setting is also common, particularly in wound care. Complicated or chronic wounds show clinical signs of delayed healing, persistent inflammation, and the production of non-viable tissue. These types of wounds also present challenges such as infection and potentially house antimicrobial-tolerant biofilms. The use of wound cleansers to aid cleaning and debridement of the wound is essential. A large proportion of skin and wound cleansers contain surfactants but there is only a small amount of data that shows the effectiveness of them in the enhancement of wound closure. This review paper aims to explore the available literature surrounding the use and mode of action of surfactants in wound healing, in particular Poloxamer 188 (Pluronic F-68) and Poloxamer 407 (Pluronic F-127), and also uncover the potential mechanisms behind the enhancement of wound healing and comparison to other surfactants used in wound care. Furthermore, the presence of a microbial biofilm in the wound is a significant factor in delayed wound healing. Therefore, the effect of clinically used surfactants on biofilms will be discussed, with emphasis on poloxamer-based surfactants.

A clinical algorithm for wound biofilm identification.

Abstract: Recognition of the existence of biofilm in chronic wounds is increasing among wound care practitioners, and a growing body of evidence indicates that biofilm contributes significantly to wound recalcitrance. While clinical guidelines regarding the involvement of biofilm in human bacterial infections have been proposed, there remains uncertainty and lack of guidance towards biofilm presence in wounds. The intention of this report is to collate knowledge and evidence of the visual and indirect clinical indicators of wound biofilm, and propose an algorithm designed to facilitate clinical recognition of biofilm and subsequent wound management practices.

Clinical Assessment of a Biofilm-disrupting Agent for the Management of Chronic Wounds Compared With Standard of Care: A Therapeutic Approach.

Abstract: OBJECTIVE The authors study the use of a biofilm-disrupting wound gel designed for wound management to determine if disrupting chronic wound biofilm would be therapeutically efficacious. MATERIALS AND METHODS This prospective, randomized, open-label clinical trial was performed from September 2014 through March 2016. Forty-three patients (22 experimental, 21 control) with chronic, recalcitrant wounds were randomized to a 12-week treatment with a biofilm-disrupting wound gel (experimental) or a broad-spectrum antimicrobial ointment (control). The wound healing rate was assessed by measuring wound size reduction and wound closure rates. RESULTS Wound size in the experimental group decreased significantly with a 71% reduction in wound area compared with 24% for the control (P < .001). Wound closure was attained in more than half of the patients (14) treated with the experimental product. Fifty-three percent of these patients achieved closure by 12 weeks as opposed to 17% for the control (P < .01). No adverse events related to the experimental product were recorded, but 2 adverse reactions occurred with the control. CONCLUSIONS The combination of the experimental product and wound debridement significantly improved wound healing rates by disrupting the biofilm, which protects multispecies bacteria within a chronic wound. Given the significant wound size reduction and closure rates observed in these long-term, nonhealing wounds, as well as the lack of related serious adverse events, the investigators believe the biofilm-disrupting wound gel to be a safe and effective treatment for recalcitrant chronic wounds.

In vitro cellular viability studies on a concentrated surfactant-based wound dressing.

Abstract: In this study, three cellular cytotoxic assays (direct contact assay, extraction assay, and cell insert assay) were applied to evaluate the effects of a concentrated surfactant gel preserved with antimicrobials and a concentrated surfactant gel with 1% silver sulfadiazine on both the mouse fibroblast cell line L929 and human dermal fibroblasts (HDFa). Also, the in vitro wound model was wounded by a 100 μL pipette tip and used to assess cell migration and wound closure after treatment with both gels. A needle-scratched membrane disruption model was used to preliminarily evaluate membrane stabilisation and the membrane-resealing effects of concentrated surfactant gels. It was demonstrated that the concentrated surfactant gel preserved with antimicrobials was not toxic to both L929 and HDFa. However, the concentrated surfactant gel with 1% silver sulfadiazine demonstrated a degree of cytotoxicity to both cell types. After treatment with a concentrated surfactant gel preserved with antimicrobials, cell movement to close the scratch gap was enhanced at 24 and 48 hours. The results also showed that cells treated with the concentrated surfactant gel preserved with antimicrobials decreased cell necrosis and improved cell resistance of the f-actin rearrangement after a needle scratch. The results demonstrated that a concentrated surfactant gel preserved with antimicrobials is non-cytotoxic and has ability to accelerate wound closure by enhancing cell mobility. Furthermore, the concentrated surfactant gel appeared to stabilise the plasma membrane and demonstrated a resealing ability and helped to retain the plasma membrane integrity and enhanced wound healing.