Silver treatments for leg ulcers: a systematic review

Silver as an Antibiotic-Independent Antimicrobial: Review of Current Formulations and Clinical Relevance

Background: The increase of multi-drug-resistant organisms has revived the use of silver as an alternative antibiotic-independent antimicrobial. Although silver's multimodal mechanism of action provides low risk for bacterial resistance, high local and uncontrolled concentrations have shown toxicity. This has resulted in efforts to develop novel silver formulations that are safer and more predictable in their application. Optimization of silver as an antimicrobial is crucial given the growing resistance profile against antibiotics. This article reviews formulations of silver used as antimicrobials, focusing on the mechanisms of action, potential for toxicity, and clinical applications. Methods: A search of four electronic databases (PubMed, Embase, MEDLINE, and Cochrane Library) was conducted for relevant studies up to January 2022. Searches were conducted for the following types of silver: ionic, nanoparticles, colloidal, silver nitrate, silver sulfadiazine, silver oxide, silver carboxylate, and AQUACEL^® (ConvaTec, Berkshire, UK). Sources were compiled based on title and abstract and screened for inclusion based on relevance and study design. Results: A review of the antimicrobial activity and uses of ionic silver, silver nanoparticles, colloidal silver, silver nitrate, silver sulfadiazine, silver oxide, Aquacel, and silver carboxylate was conducted. The mechanisms of action, clinical uses, and potential for toxicity were studied, and general trends between earlier and more advanced formulations noted. Conclusions: Early forms of silver have more limited utility because of their uncontrolled release of silver ions and potential for systemic toxicity. Multiple new formulations show promise; however, there is a need for more prospective in vivo studies to validate the clinical potential of these formulations.

Role of copper nanoparticles in wound healing for chronic wounds: literature review

Chronic wounds are defined as wounds that fail to proceed through the normal phases of wound healing in an orderly and timely manner. The most common and inevitable impairment to wound healing is the installation of an infection, usually in the case of chronic wounds. Therefore, the objective of the present review was to identify the importance of copper nanoparticles in dressings for wound healing. Nanoparticles such as silver, gold and copper combat infectious processes through the inhibition of protein synthesis, peroxidation of the cell membrane and destroying the nucleic acids of bacteria and viruses. Among bioactive nanoparticles, copper plays a complex role in various cells, it modulates several cytokines and growth factor mechanisms of action and is essentially involved in all stages of the wound healing process. More importantly, copper plays a key role in skin regeneration and angiogenesis and accelerates the healing process through induction of vascular endothelial growth factor (VEGF) and angiogenesis by hypoxia-induced factor-1-alpha (HIF-1α) action where copper enhances HIF-1α expression and HIF-1α binding to the critical motifs in the promoter and putative enhancer regions of HIF-1-regulated genes.

Healing of Chronic Wounds by Copper Oxide-Impregnated Wound Dressings-Case Series

Novel antimicrobial wound dressings impregnated with copper oxide micro-particles have been cleared for treatment of acute and chronic wounds. Our objective is to provide preliminary data regarding the potential benefit of using these novel wound dressings including in non-infected wounds. Methods involved the treatment of wounds that responded partially or poorly to conventional wound healing treatments with copper oxide impregnated wound dressings in patients with a range of etiologies. Ten cases of patients with etiologies such as diabetes mellitus, sickle cell disease, renal failure, and necrotizing fasciitis, in which the application of copper oxide impregnated wound dressings in infected and non-infected wounds, which resulted in significant enhanced wound healing, are presented. This was exemplified by clearing of the wound infections, reduction of the fibrous and/or necrotic tissue and by intense granulation, epithelialization, and wound closure. The described 10 case reports support our hypothesis that the copper oxide-containing wound dressing not only confers protection to the wound and the dressing from microbial contamination, and in some cases may help clear the wound infections, but in addition and more importantly, stimulate skin regeneration and wound healing. Our findings are in line with previous animal and in vitro studies showing that copper plays a key role in angiogenesis and skin regeneration. These case reports support the notion that the use of copper oxide impregnated wound dressings may be an important intervention in the arsenal of wound treatment modalities, especially in hard to heal wounds.

Tissue reaction and anti-biofilm action of new biomaterial composed of latex from Hancornia speciosa Gomes and silver nanoparticles

In this work, the natural latex extracted from Harconia speciosa was incorporated with silver nanoparticles (AgNP) to compose a functional biomaterial associating the intrinsic angiogenic activity of the latex and the antimicrobial activity of AgNP. Tissue reaction after subcutaneous implantation in dorsum of rats of membranes without AgNP and with 0.05%, 0.4% AgNP was compared at 3, 7 and 25 days. No statistically significant difference in the tissue response of the different biomaterials was observed, indicating that AgNP did not interfere with the inflammatory reaction (p > 0.05) or with the angiogenic activity of latex. Biomembranes were also tested against bacterial biofilm formation by Staphylococcus aureus and the antimicrobial activity of the new biomaterial can be found with bacteria crenation (0.05% AgNP) and no biofilm deposition (0.4% AgNP). Therefore, this biomaterial has interesting properties for the tissue repair process and may be feasible for future applications as dressing.

Silver dressings for the healing of venous leg ulcer: A meta-analysis and systematic review

This study was aimed to evaluate whether silver-containing dressings were superior to other types of dressings in the treatment of venous leg ulcers (VLU) and their specific advantages.Eight databases (Cochrane Library, PubMed, Web of Science, Ovid-Medline, Wanfang, VIP, China Biology Medicine, and China National Knowledge Infrastructure) were systematically reviewed from inception to May 2019 for randomized controlled trials (RCTs). The primary outcome was complete wound healing, and the secondary outcomes included absolute wound size changes (change of cm area since baseline), relative changes (percentage change of area relative to baseline), and healing rate. Two reviewers independently evaluated the risk of bias using the Cochrane Collaboration assessment tool and extracted the data according to the predesigned table. All analyses were performed using the latest Review Manager Software (version 5.3).A total of 8 studies qualified and were included in the meta-analysis, including 1057 patients (experiment: 526, control: 531). Both complete wound healing and wound healing rates were reported in 5 studies. Two and 3 studies reported the effect of silver dressings on absolute and relative wound size changes, respectively. Most of the studies used intention-to-treat analysis.There was sufficient evidence that silver-containing dressings can accelerate the healing rate of chronic VLU and improve their healing in a short duration of time. However, compared with other dressings, clinical trials with long-term follow-up data are needed to confirm whether silver dressings have advantages regarding complete wound healing.

Silver in Wound Care-Friend or Foe?: A Comprehensive Review

Due to its strong antimicrobial activity, silver is a commonly used adjunct in wound care. However, it also has the potential to impair healing by exerting toxic effects on keratinocytes and fibroblasts. The published literature on the use of silver in wound care is very heterogeneous, making it difficult to generate useful treatment guidelines.

Mesenchymal stem cell in venous leg ulcer: An intoxicating therapy

Venous leg ulcers (VLU) are a prevalent and reoccurring type of complicated wound, turning as a considerable public healthcare issue, with critical social and economic concern. There are both medical and surgical therapies to treat venous leg ulcers; however, a cure does not yet exist. Mesenchymal stem cells (MSC) are capable and proved of accelerating wound healing in vivo and their study with human chronic wounds is currently awaited. MSCs are a promising source of adult progenitor cells for cellular therapy and have been demonstrated to differentiate into various mesenchymal cell lineages. They have a crucial and integral role in native wound healing by regulating immune response and inflammation. Improved understanding of the cellular and molecular mechanisms at work in delayed wound healing compels to the development of cellular therapy in VLU. This review focuses on the current treatment option of VLU and further emphasizing the role of MSCs in accelerating the healing process. With further understanding of the mechanism of action of these cells in wound improvement and, the involvement of cytokines can also be revealed that could be used for the therapeutic purpose for VLU healing. Clinical uses of MSCs have been started already, and induced MSCs are surely a promising tool or compelling therapy for VLU.

Wounds research for patient benefit: a 5-year programme of research

Background

Complex wounds are those that heal by secondary intention and include lower-limb ulcers, pressure ulcers and some surgical wounds. The care of people with complex wounds is costly, with care mainly being delivered by community nurses. There is a lack of current, high-quality data regarding the numbers and types of people affected, care received and outcomes achieved.

Objectives

To (1) assess how high-quality data about complex wounds can be captured effectively for use in both service planning and research while ensuring integration with current clinical data collection systems and minimal impact on staff time; (2) investigate whether or not a clinical register of people with complex wounds could give valid estimates of treatment effects, thus reducing dependence on large-scale randomised controlled trials (RCTs); (3) identify the most important research questions and outcomes for people with complex wounds from the perspectives of patients, carers and health-care professionals; (4) evaluate the potential contributions to decision-making of individual patient data meta-analysis and mixed treatment comparison meta-analysis; and (5) complete and update systematic reviews in topic areas of high priority.

Methods

To meet objectives 1 and 2 we conducted a prevalence survey and developed and piloted a longitudinal disease register. A consultative, deliberative method and in-depth interviews were undertaken to address objective 3. To address objectives 4 and 5 we conducted systematic reviews including mixed treatment comparison meta-analysis.

Results

From the prevalence survey we estimated the point prevalence of all complex wounds to be 1.47 per 1000 people (95% confidence interval 1.38 to 1.56 per 1000 people). Pressure ulcers and venous leg ulcers were the most common type of complex wound. A total of 195 people with a complex wound were recruited to a complex wounds register pilot. We established the feasibility of correctly identifying, extracting and transferring routine NHS data into the register; however, participant recruitment, data collection and tracking individual wounds in people with multiple wounds were challenging. Most patients and health professionals regarded healing of the wound as the primary treatment goal. Patients were greatly troubled by the social consequences of having a complex wound. Complex wounds are frequently a consequence of, and are themselves, a long-term condition but treatment is usually focused on healing the wound. Consultative, deliberative research agenda setting on pressure ulcer prevention and treatment with patients, carers and clinicians yielded 960 treatment uncertainties and a top 12 list of research priorities. Of 167 RCTs of complex wound treatments in a systematic review of study quality, 41% did not specify a primary outcome and the overall quality of the conduct and reporting of the research was poor. Mixed-treatment comparison meta-analysis in areas of high priority identified that matrix hydrocolloid dressings had the highest probability (70%) of being the most effective dressing for diabetic foot ulcers, whereas a hyaluronan fleece dressing had the highest probability (35%) of being the most effective dressing for venous ulcers; however, the quality of this evidence was low and uncertainty is high.

Conclusions

Complex wounds are common and costly with a poor evidence base for many frequent clinical decisions. There is little routine clinical data collection in community nursing. A prospective complex wounds register has the potential to both assist clinical decision-making and provide important research evidence but would be challenging to implement without investment in information technology in NHS community services. Future work should focus on developing insights into typical wound healing trajectories, identifying factors that are prognostic for healing and assessing the cost-effectiveness of selected wound treatments.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Mesenchymal Stem Cells in Chronic Wounds: The Spectrum from Basic to Advanced Therapy

Significance: Almost 7 million Americans have chronic cutaneous wounds and billions of dollars are spent on their treatment. The number of patients with nonhealing wounds keeps increasing worldwide due to an ever-aging population, increasing number of obese and diabetic patients, and cardiovascular disease. Recent Advances: Advanced treatments for difficult wounds are needed. Therapy with mesenchymal stem cells (MSCs) is attractive due to their differentiating potential, their immunomodulating properties, and their paracrine effects. Critical Issues: New technologies (including growth factors and skin substitutes) are now widely used for stimulating wound healing. However, in spite of these advances, the percentage of complete wound closure in most clinical situations is around 50-60%. Moreover, there is a high rate of wound recurrence. Future Directions: Recently, it has been demonstrated that MSCs speed up wound healing by decreasing inflammation, by promoting angiogenesis, and by decreasing scarring. However, there are some potential limitations to successful MSC therapy. These limitations include the need to improve cell delivery methods, cell viability, heterogeneity in MSC preparations, and suboptimal wound bed preparation. Further large, controlled clinical trials are needed to establish the safety of MSCs before widespread clinical application.

Challenges in the Treatment of Chronic Wounds

Significance: Chronic wounds include, but are not limited, to diabetic foot ulcers, venous leg ulcers, and pressure ulcers. They are a challenge to wound care professionals and consume a great deal of healthcare resources around the globe. This review discusses the pathophysiology of complex chronic wounds and the means and modalities currently available to achieve healing in such patients. Recent Advances: Although often difficult to treat, an understanding of the underlying pathophysiology and specific attention toward managing these perturbations can often lead to successful healing. Critical Issues: Overcoming the factors that contribute to delayed healing are key components of a comprehensive approach to wound care and present the primary challenges to the treatment of chronic wounds. When wounds fail to achieve sufficient healing after 4 weeks of standard care, reassessment of underlying pathology and consideration of the need for advanced therapeutic agents should be undertaken. However, selection of an appropriate therapy is often not evidence based. Future Directions: Basic tenets of care need to be routinely followed, and a systematic evaluation of patients and their wounds will also facilitate appropriate care. Underlying pathologies, which result in the failure of these wounds to heal, differ among various types of chronic wounds. A better understanding of the differences between various types of chronic wounds at the molecular and cellular levels should improve our treatment approaches, leading to better healing rates, and facilitate the development of new more effective therapies. More evidence for the efficacy of current and future advanced wound therapies is required for their appropriate use.

Seeking effective interventions to treat complex wounds: an overview of systematic reviews

BACKGROUND

Numerous, often multi-faceted regimens are available for treating complex wounds, yet the evidence of these interventions is recondite across the literature. We aimed to identify effective interventions to treat complex wounds through an overview of systematic reviews.

METHODS

MEDLINE (OVID interface, 1946 until October 26, 2012), EMBASE (OVID interface, 1947 until October 26, 2012), and the Cochrane Database of Systematic Reviews (Issue 10 of 12, 2012) were searched on October 26, 2012. Systematic reviews that examined adults receiving care for their complex wounds were included. Two reviewers independently screened the literature, abstracted data, and assessed study quality using the Assessment of Multiple Systematic Reviews (AMSTAR) tool.

RESULTS

Overall, 99 systematic reviews were included after screening 6,200 titles and abstracts and 422 full-texts; 54 were systematic reviews with a meta-analysis (including data on over 54,000 patients) and 45 were systematic reviews without a meta-analysis. Overall, 44% of included reviews were rated as being of high quality (AMSTAR score ≥ 8). Based on data from systematic reviews including a meta-analysis with an AMSTAR score ≥ 8, promising interventions for complex wounds were identified. These included bandages or stockings (multi-layer, high compression) and wound cleansing for venous leg ulcers; four-layer bandages for mixed arterial/venous leg ulcers; biologics, ultrasound, and hydrogel dressings for diabetic leg/foot ulcers; hydrocolloid dressings, electrotherapy, air-fluidized beds, and alternate foam mattresses for pressure ulcers; and silver dressings and ultrasound for unspecified mixed complex wounds. For surgical wound infections, topical negative pressure and vacuum-assisted closure were promising interventions, but this was based on evidence from moderate to low quality systematic reviews.

CONCLUSIONS

Numerous interventions can be utilized for patients with varying types of complex wounds, yet few treatments were consistently effective across all outcomes throughout the literature. Clinicians and patients can use our results to tailor effective treatment according to type of complex wound. Network meta-analysis will be of benefit to decision-makers, as it will permit multiple treatment comparisons and ranking of the effectiveness of all interventions. Please see related article: http://dx.doi.org/10.1186/s12916-015-0326-3.

Clinical update on nursing home medicine: 2013

This is the seventh article in the series of Clinical Updates on Nursing Home Care. The topics covered are antiresorptive drugs, hip fracture, hypertension, orthostatic hypotension, depression, undernutrition, anorexia, cachexia, sarcopenia, exercise, pain, and behavioral and psychological symptoms of dementia.

Cost-effective use of silver dressings for the treatment of hard-to-heal chronic venous leg ulcers

AIM

To estimate the cost-effectiveness of silver dressings using a health economic model based on time-to-wound-healing in hard-to-heal chronic venous leg ulcers (VLUs).

BACKGROUND

Chronic venous ulceration affects 1-3% of the adult population and typically has a protracted course of healing, resulting in considerable costs to the healthcare system. The pathogenesis of VLUs includes excessive and prolonged inflammation which is often related to critical colonisation and early infection. The use of silver dressings to control this bioburden and improve wound healing rates remains controversial.

METHODS

A decision tree was constructed to evaluate the cost-effectiveness of treatment with silver compared with non-silver dressings for four weeks in a primary care setting. The outcomes: 'Healed ulcer', 'Healing ulcer' or 'No improvement' were developed, reflecting the relative reduction in ulcer area from baseline to four weeks of treatment. A data set from a recent meta-analysis, based on four RCTs, was applied to the model.

RESULTS

Treatment with silver dressings for an initial four weeks was found to give a total cost saving (£141.57) compared with treatment with non-silver dressings. In addition, patients treated with silver dressings had a faster wound closure compared with those who had been treated with non-silver dressings.

CONCLUSION

The use of silver dressings improves healing time and can lead to overall cost savings. These results can be used to guide healthcare decision makers in evaluating the economic aspects of treatment with silver dressings in hard-to-heal chronic VLUs.

Next science wound gel technology, a novel agent that inhibits biofilm development by gram-positive and gram-negative wound pathogens

Loss of the skin barrier facilitates the colonization of underlying tissues with various bacteria, where they form biofilms that protect them from antibiotics and host responses. Such wounds then become chronically infected. Topical antimicrobials are a major component of chronic wound therapy, yet currently available topical antimicrobials vary in their effectiveness on biofilm-forming pathogens. In this study, we evaluated the efficacy of Next Science wound gel technology (NxtSc), a novel topical agent designed to kill planktonic bacteria, penetrate biofilms, and kill the bacteria within. In vitro quantitative analysis, using strains isolated from wounds, showed that NxtSc inhibited biofilm development by Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae by inhibiting bacterial growth. The gel formulation NxtSc-G5, when applied to biofilms preformed by these pathogens, reduced the numbers of bacteria present by 7 to 8 log10 CFU/disc or CFU/g. In vivo, NxtSc-G5 prevented biofilm formation for 72 h when applied at the time of wounding and infection and eliminated biofilm infection when applied 24 h after wounding and infection. Storage of NxtSc-G5 at room temperature for 9 months did not diminish its efficacy. These results establish that NxtSc is efficacious in vitro and in vivo in preventing infection and biofilm development by different wound pathogens when applied immediately and in eliminating biofilm infection already established by these pathogens. This novel antimicrobial agent, which is nontoxic and has a usefully long shelf life, shows promise as an effective agent for the prevention and treatment of biofilm-related infections.

Chitosan-based copper nanocomposite accelerates healing in excision wound model in rats

Copper possesses efficacy in wound healing which is a complex phenomenon involving various cells, cytokines and growth factors. Copper nanoparticles modulate cells, cytokines and growth factors involved in wound healing in a better way than copper ions. Chitosan has been shown to be beneficial in healing because of its antibacterial, antifungal, biocompatible and biodegradable polymeric nature. In the present study, chitosan-based copper nanocomposite (CCNC) was prepared by mixing chitosan and copper nanoparticles. CCNC was applied topically to evaluate its wound healing potential and to study its effects on some important components of healing process in open excision wound model in adult Wistar rats. Significant increase in wound contraction was observed in the CCNC-treated rats. The up-regulation of vascular endothelial growth factor (VEGF) and transforming growth factor-beta1(TGF-β1) by CCNC-treatment revealed its role in facilitating angiogenesis, fibroblast proliferation and collagen deposition. The tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) were significantly decreased and increased, respectively, in CCNC-treated rats. Histological evaluation showed more fibroblast proliferation, collagen deposition and intact re-epithelialization in CCNC-treated rats. Immunohistochemistry of CD31 revealed marked increase in angiogenesis. Thus, we concluded that chitosan-based copper nanocomposite efficiently enhanced cutaneous wound healing by modulation of various cells, cytokines and growth factors during different phases of healing process.

Antibiofilm Efficacy of DispersinB(®) Wound Spray Used in Combination with a Silver Wound Dressing

Chronic wounds including diabetic foot ulcers, pressure ulcers, and venous leg ulcers are a worldwide health problem. As the traditional methods of treatment have proven ineffective against chronic wounds involving biofilms, there is an unmet clinical need for developing products with an antibiofilm component that inhibits and/or disrupts biofilms and thus make the biofilm-embedded bacteria more susceptible to antimicrobial therapy. We developed a DispersinB® antibiofilm enzyme-based wound spray for treating chronic wounds in conjunction with an antimicrobial. Under in vitro conditions, the DispersinB® and Acticoat™ combination performed significantly better (P < 0.05) than Acticoat™ alone, indicating the synergy between the two compounds because of DispersinB® enhancing the antimicrobial activity of Acticoat™. Furthermore, DispersinB® wound spray enhanced the antimicrobial activity of Acticoat™ in a chronic wound mouse model of methicillin-resistant Staphylococcus aureus (MRSA) infection. Thus, this novel combination of DispersinB® and Acticoat™, an antimicrobial dressing, prompts clinical evaluation for potential applications in biofilm-based chronic wound management.

Antibiotics and antiseptics for venous leg ulcers

BACKGROUND

Venous leg ulcers are a type of chronic wound affecting up to 1% of adults in developed countries at some point during their lives. Many of these wounds are colonised by bacteria or show signs of clinical infection. The presence of infection may delay ulcer healing. Two main strategies are used to prevent and treat clinical infection in venous leg ulcers: systemic antibiotics and topical antibiotics or antiseptics.

OBJECTIVES

The objective of this review was to determine the effects of systemic antibiotics and topical antibiotics and antiseptics on the healing of venous ulcers.

SEARCH METHODS

In May 2013, for this second update, we searched the Cochrane Wounds Group Specialised Register (searched 24 May 2013); the Cochrane Central Register of Controlled Trials (CENTRAL 2013, Issue 4); Ovid MEDLINE (1948 to Week 3 May 2013); Ovid MEDLINE (In-Process & Other Non-indexed Citations, 22 May 2013); Ovid EMBASE (1980 to Week 20 2013); and EBSCO CINAHL (1982 to 17 May 2013). No language or publication date restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting people with venous leg ulceration, evaluating at least one systemic antibiotic, topical antibiotic or topical antiseptic that reported an objective assessment of wound healing (e.g. time to complete healing, frequency of complete healing, change in ulcer surface area) were eligible for inclusion. Selection decisions were made by two review authors while working independently.

DATA COLLECTION AND ANALYSIS

Information on the characteristics of participants, interventions and outcomes was recorded on a standardised data extraction form. In addition, aspects of trial methods were extracted, including randomisation, allocation concealment, blinding of participants and outcome assessors, incomplete outcome data and study group comparability at baseline. Data extraction and validity assessment were conducted by one review author and were checked by a second. Data were pooled when appropriate.

MAIN RESULTS

Forty-five RCTs reporting 53 comparisons and recruiting a total of 4486 participants were included, Many RCTs were small, and most were at high or unclear risk of bias. Ulcer infection status at baseline and duration of follow-up varied across RCTs. Five RCTs reported eight comparisons of systemic antibiotics, and the remainder evaluated topical preparations: cadexomer iodine (11 RCTs reporting 12 comparisons); povidone-iodine (six RCTs reporting seven comparisons); peroxide-based preparations (four RCTs reporting four comparisons); honey-based preparations (two RCTs reporting two comparisons); silver-based preparations (12 RCTs reporting 13 comparisons); other topical antibiotics (three RCTs reporting five comparisons); and other topical antiseptics (two RCTs reporting two comparisons). Few RCTs provided a reliable estimate of time to healing; most reported the proportion of participants with complete healing during the trial period. Systemic antibioticsMore participants were healed when they were prescribed levamisole (normally used to treat roundworm infection) compared with placebo: risk ratio (RR) 1.31 (95% CI 1.06 to 1.62). No between-group differences were detected in terms of complete healing for other comparisons: antibiotics given according to antibiogram versus usual care; ciprofloxacin versus standard care/placebo; trimethoprim versus placebo; ciprofloxacin versus trimethoprim; and amoxicillin versus topical povidone-iodine. Topical antibiotics and antiseptics Cadexomer iodine: more participants were healed when given cadexomer iodine compared with standard care. The pooled estimate from four RCTs for complete healing at four to 12 weeks was RR 2.17 (95% CI 1.30 to 3.60). No between-group differences in complete healing were detected when cadexomer iodine was compared with the following: hydrocolloid dressing; paraffin gauze dressing; dextranomer; and silver-impregnated dressings.Povidone iodine: no between-group differences in complete healing were detected when povidone-iodine was compared with the following: hydrocolloid; moist or foam dressings according to wound status; and growth factor. Time to healing estimates for povidone-iodine versus dextranomer, and for povidone-iodine versus hydrocolloid, were likely to be unreliable.Peroxide-based preparations: four RCTs reported findings in favour of peroxide-based preparations when compared with usual care for surrogate healing outcomes (change in ulcer area). There was no report of complete healing.Honey-based preparations: no between-group difference in time to healing or complete healing was detected for honey-based products when compared with usual care.Silver-based preparations: no between-group differences in complete healing were detected when 1% silver sulphadiazine ointment was compared with standard care/placebo and tripeptide copper complex; or when different brands of silver-impregnated dressings were compared; or when silver-impregnated dressings were compared with non-antimicrobial dressings.Other topical antibiotics: data from one RCT suggested that more participants healed at four weeks when treated with an enzymatic cleanser (a non-antibiotic preparation) compared with a chloramphenicol-containing ointment (additional active ingredients also included in the ointment): RR 0.13 (95% CI 0.02 to 0.99). No between-group differences in complete healing were detected for framycetin sulphate ointment versus enzymatic cleanser; chloramphenicol ointment versus framycetin sulphate ointment; mupirocin ointment versus vehicle; and topical antibiotics given according to antibiogram versus an herbal ointment.Other topical antiseptics: data from one RCT suggested that more participants receiving an antiseptic ointment (ethacridine lactate) had responsive ulcers (defined as > 20% reduction in area) at four weeks when compared with placebo: RR 1.45 (95% CI 1.21 to 1.73). Complete healing was not reported. No between-group difference was detected between chlorhexidine solution and usual care.

AUTHORS' CONCLUSIONS

At present, no evidence is available to support the routine use of systemic antibiotics in promoting healing of venous leg ulcers. However, the lack of reliable evidence means that it is not possible to recommend the discontinuation of any of the agents reviewed. In terms of topical preparations, some evidence supports the use of cadexomer iodine. Current evidence does not support the routine use of honey- or silver-based products. Further good quality research is required before definitive conclusions can be drawn about the effectiveness of povidone-iodine, peroxide-based preparations, ethacridine lactate, chloramphenicol, framycetin, mupirocin, ethacridine or chlorhexidine in healing venous leg ulceration. In light of the increasing problem of bacterial resistance to antibiotics, current prescribing guidelines recommend that antibacterial preparations should be used only in cases of clinical infection, not for bacterial colonisation.

Antibiotics and antiseptics for venous leg ulcers

BACKGROUND

Venous leg ulcers are a type of chronic wound affecting up to 1% of adults in developed countries at some point during their lives. Many of these wounds are colonised by bacteria or show signs of clinical infection. The presence of infection may delay ulcer healing. Two main strategies are used to prevent and treat clinical infection in venous leg ulcers: systemic antibiotics and topical antibiotics or antiseptics.

OBJECTIVES

The objective of this review was to determine the effects of systemic antibiotics and topical antibiotics and antiseptics on the healing of venous ulcers; review authors also examined the effects of these interventions on clinical infection, bacterial flora, bacterial resistance, ulcer recurrence, adverse effects, patient satisfaction, health-related quality of life and costs.

SEARCH METHODS

In May 2013, for this second update, we searched the Cochrane Wounds Group Specialised Register (searched 24 May 2013); the Cochrane Central Register of Controlled Trials (CENTRAL 2013, Issue 4); Ovid MEDLINE (1948 to Week 3 May 2013); Ovid MEDLINE (In-Process & Other Non-indexed Citations, 22 May 2013); Ovid EMBASE (1980 to Week 20 2013); and EBSCO CINAHL (1982 to 17 May 2013). No language or publication date restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting people with venous leg ulceration, evaluating at least one systemic antibiotic, topical antibiotic or topical antiseptic that reported an objective assessment of wound healing (e.g. time to complete healing, frequency of complete healing, change in ulcer surface area) were eligible for inclusion. Selection decisions were made by two review authors while working independently.

DATA COLLECTION AND ANALYSIS

Information on the characteristics of participants, interventions and outcomes was recorded on a standardised data extraction form. In addition, aspects of trial methods were extracted, including randomisation, allocation concealment, blinding of participants and outcome assessors, incomplete outcome data and study group comparability at baseline. Data extraction and validity assessment were conducted by one review author and were checked by a second. Data were pooled when appropriate.

MAIN RESULTS

Forty-five RCTs reporting 53 comparisons and recruiting a total of 4486 participants were included, Many RCTs were small, and most were at high or unclear risk of bias. Ulcer infection status at baseline and duration of follow-up varied across RCTs. Five RCTs reported eight comparisons of systemic antibiotics, and the remainder evaluated topical preparations: cadexomer iodine (11 RCTs reporting 12 comparisons); povidone-iodine (six RCTs reporting seven comparisons); peroxide-based preparations (four RCTs reporting four comparisons); honey-based preparations (two RCTs reporting two comparisons); silver-based preparations (12 RCTs reporting 13 comparisons); other topical antibiotics (three RCTs reporting five comparisons); and other topical antiseptics (two RCTs reporting two comparisons). Few RCTs provided a reliable estimate of time to healing; most reported the proportion of participants with complete healing during the trial period. Systemic antibioticsMore participants were healed when they were prescribed levamisole (normally used to treat roundworm infection) compared with placebo: risk ratio (RR) 1.31 (95% CI 1.06 to 1.62). No between-group differences were detected in terms of complete healing for other comparisons: antibiotics given according to antibiogram versus usual care; ciprofloxacin versus standard care/placebo; trimethoprim versus placebo; ciprofloxacin versus trimethoprim; and amoxicillin versus topical povidone-iodine. Topical antibiotics and antisepticsCadexomer iodine: more participants were healed when given cadexomer iodine compared with standard care. The pooled estimate from four RCTs for complete healing at four to 12 weeks was RR 2.17 (95% CI 1.30 to 3.60). No between-group differences in complete healing were detected when cadexomer iodine was compared with the following: hydrocolloid dressing; paraffin gauze dressing; dextranomer; and silver-impregnated dressings.Povidone iodine: no between-group differences in complete healing were detected when povidone-iodine was compared with the following: hydrocolloid; moist or foam dressings according to wound status; and growth factor. Time to healing estimates for povidone-iodine versus dextranomer, and for povidone-iodine versus hydrocolloid, were likely to be unreliable.Peroxide-based preparations: four RCTs reported findings in favour of peroxide-based preparations when compared with usual care for surrogate healing outcomes (change in ulcer area). There was no report of complete healing.Honey-based preparations: no between-group difference in time to healing or complete healing was detected for honey-based products when compared with usual care.Silver-based preparations: no between-group differences in complete healing were detected when 1% silver sulphadiazine ointment was compared with standard care/placebo and tripeptide copper complex; or when different brands of silver-impregnated dressings were compared; or when silver-impregnated dressings were compared with non-antimicrobial dressings.Other topical antibiotics: data from one RCT suggested that more participants healed at four weeks when treated with an enzymatic cleanser (a non-antibiotic preparation) compared with a chloramphenicol-containing ointment (additional active ingredients also included in the ointment): RR 0.13 (95% CI 0.02 to 0.99). No between-group differences in complete healing were detected for framycetin sulphate ointment versus enzymatic cleanser; chloramphenicol ointment versus framycetin sulphate ointment; mupirocin ointment versus vehicle; and topical antibiotics given according to antibiogram versus an herbal ointment.Other topical antiseptics: data from one RCT suggested that more participants receiving an antiseptic ointment (ethacridine lactate) had responsive ulcers (defined as > 20% reduction in area) at four weeks when compared with placebo: RR 1.45 (95% CI 1.21 to 1.73). Complete healing was not reported. No between-group difference was detected between chlorhexidine solution and usual care.

AUTHORS' CONCLUSIONS

At present, no evidence is available to support the routine use of systemic antibiotics in promoting healing of venous leg ulcers. However, the lack of reliable evidence means that it is not possible to recommend the discontinuation of any of the agents reviewed. In terms of topical preparations, some evidence supports the use of cadexomer iodine. Current evidence does not support the routine use of honey- or silver-based products. Further good quality research is required before definitive conclusions can be drawn about the effectiveness of povidone-iodine, peroxide-based preparations, ethacridine lactate, chloramphenicol, framycetin, mupirocin, ethacridine or chlorhexidine in healing venous leg ulceration. In light of the increasing problem of bacterial resistance to antibiotics, current prescribing guidelines recommend that antibacterial preparations should be used only in cases of clinical infection, not for bacterial colonisation.

The use of biatain Ag in hard-to-heal venous leg ulcers: meta-analysis of randomised controlled trials

Background

Venous leg ulcers are common, troublesome, and their failure to heal is often related to a heavy bio-burden. Ionized silver has both anti-inflammatory and antimicrobial properties. The ulcer healing properties of the silver releasing foam dressing Biatain Ag has been examined in 4 randomized controlled trials (RCTs).

Aim

To evaluate ulcer healing through a meta-analytic approach after treatment with either Biatain Ag or a non-active dressing.

Patients and Methods

685 subjects with pure or mixed hard-to-heal venous leg ulcers were included in the meta-analysis.

Results

Biatain Ag showed a significant treatment effect (p<0.0001), responder rate (p<0.001), and healing rate (p = 0.002).

Conclusion

The meta-analysis of the 4 RCTs provided statistical significant evidence to support the use of Biatain Ag dressing in treatment of hard-to-heal venous leg ulcers.

Use of silver in the prevention and treatment of infections: silver review

BACKGROUND

The use of silver for the treatment of various maladies or to prevent the transmission of infection dates back to at least 4000 b.c.e. Medical applications are documented in the literature throughout the 17th and 18th centuries. The bactericidal activity of silver is well established. Silver nitrate was used topically throughout the 1800 s for the treatment of burns, ulcerations, and infected wounds, and although its use declined after World War II and the advent of antibiotics, Fox revitalized its use in the form of silver sulfadiazine in 1968.

METHOD

Review of the pertinent English-language literature.

RESULTS

Since Fox's work, the use of topical silver to reduce bacterial burden and promote healing has been investigated in the setting of chronic wounds and ulcers, post-operative incision dressings, blood and urinary catheter designs, endotracheal tubes, orthopedic devices, vascular prostheses, and the sewing ring of prosthetic heart valves. The beneficial effects of silver in reducing or preventing infection have been seen in the topical treatment of burns and chronic wounds and in its use as a coating for many medical devices. However, silver has been unsuccessful in certain applications, such as the Silzone heart valve. In other settings, such as orthopedic hardware coatings, its benefit remains unproved.

CONCLUSION

Silver remains a reasonable addition to the armamentarium against infection and has relatively few side effects. However, one should weigh the benefits of silver-containing products against the known side effects and the other options available for the intended purpose when selecting the most appropriate therapy.

A systematic review of silver-containing dressings and topical silver agents (used with dressings) for burn wounds

Silver preparations are commonly used for burns, but evidence of their effectiveness remains poorly defined. The aim of the study was to evaluate the effectiveness of silver-containing dressings and topical silver for preventing infection and promoting healing in burns wounds through a meta-analysis of the available evidence. The Cochrane Central Register of Controlled Trials and relevant databases were searched. Drug companies and experts in this field were also contacted. Randomised controlled trials (RCTs) of silver dressings or topical silver (used with dressings) compared with non-silver dressings were eligible for inclusion. We identified 14 RCTs involving 877 participants. One small trial of a silver-containing dressing showed significantly better healing time compared to the control [MD -3.6; 95% CI -4.94 to -2.26 for partial thickness burns and MD -3.9; 95% CI -4.54 to -3.26 for superficial burns]. Topical silver showed significantly worse healing time compared to the non-silver group [WMD 3.96; 95% CI 2.41-5.51] and showed no evidence of effectiveness in preventing wounds infection [WMD 2.48; 95% CI 0.39-15.73]. Our review suggests that silver-containing dressings and topical silver were either no better or worse than control dressings in preventing wound infection and promoting healing of burn wounds.

Anti-biofilm efficacy of a lactoferrin/xylitol wound hydrogel used in combination with silver wound dressings

With an epidemic increase in obesity combined with an ageing population, chronic wounds such as diabetic foot ulcers, pressure ulcers and venous leg ulcers are an increasing clinical concern. Recent studies have shown that bacterial biofilms are a major contributor to wound bioburden and interfere with the normal wound healing process; therefore, rational design of wound therapies should include analysis of anti-biofilm characteristics. Studies using the combined treatment of bacterial biofilms with the innate immune molecule lactoferrin and the rare sugar-alcohol xylitol have demonstrated an antimicrobial capacity against a clinical wound isolate. Studies presented here used a colony-drip-flow reactor biofilm model to assess the anti-biofilm efficacy of a lactoferrin/xylitol hydrogel used in combination with commercially available silver-based wound dressings. Log reductions in biofilm viability are compared with a commercially available wound hydrogel used in combination with the silver-based wound dressings. For both a single species biofilm and a dual species biofilm, the lactoferrin/xylitol hydrogel in combination with the silver wound dressing Acticoat™ had a statistically significant reduction in biofilm viability relative to the commercially available wound hydrogel. This study also demonstrated a statistical interaction between the lactoferrin/xylitol hydrogel and the silver wound dressing.

An overview of the evidence on the efficacy of silver dressings

While there is a plethora of clinical and anecdotal evidence on the efficacy of silver dressings, there is no rigorous RCT data to support this. This has led procurement managers to defer the inclusion of silver dressings on wound formularies, despite its clinical popularity. This article gives an overview of the evidence on topical antimicrobials, in order to determine whether there is a case for such a stance.

An approach to assessing evidence that can inform clinical decision-making

Following the Cochrane meta-analyses findings, doubts are being expressed about efficacy of silver dressings. However, the need for topical antimicrobials has not diminished, and the evidence for non-silver agents is no better than that for silver. This article describes an alternative system to Cochrane for analysing the evidence base, and suggests a practical approach to making a case for silver to procurement managers.

Silver treatments and silver-impregnated dressings for the healing of leg wounds and ulcers: a systematic review and meta-analysis

Previous systematic reviews of silver-impregnated dressings have been contradictory regarding the healing of leg wounds/ulcers. Our systematic review was restricted to randomized controlled trials. Cochrane Library, Scopus, and MEDLINE databases were searched using the term "silver" in combination with "wound" or "ulcer" (and plural versions) without date/language restriction. Study quality was assessed and meta-analysis conducted for complete wound healing, wound size reduction, and healing rates. Overall study quality was fair with most studies having some bias. Evidence for wound healing using individual studies was poor. Meta-analyses found strong evidence for wound healing based on wound size reduction but no evidence based on complete wound-healing or healing rates. Although our results provide some evidence that silver-impregnated dressings improve the short-term healing of wounds and ulcers, long-term effects remain unclear. Clinical trial data with longer follow-up times are needed to address these issues.

Silver: an age-old treatment modality in modern times

The use of silver as an antimicrobial for infection spans hundreds of years. The ancient Greeks and Romans used silver to disinfect their water and food supplies. Silver was also used in ancient times to treat burns and wounds as a wound dressing. Silver solutions were approved by the U.S. Food and Drug Administration in the 1920s. Since that time, silver has established itself as an effective and well-known treatment modality for and in the prevention of high-risk infection in clinical wound care (http://int.hansaplast.com/med-info/wound-care-beautiful-healing/silver-tech.html).

Wound healing in older adults

Chronic wounds affect a substantial number of individuals throughout the world, and impose a significant psychological, physical and economic burden. As the population ages, the incidence of chronic wounds is also expected to rise. Clinicians struggle to find the optimal approaches to prevention and treatment of these nonhealing or slow-healing wounds. This review discusses current best practices and evidence-based recommendations for preventing and managing chronic wounds in general, as well as pressure ulcers, diabetic foot ulcers and venous leg ulcers specifically. This review highlights the significant gaps and inconsistencies in the current evidence base for chronic wound care, which have hindered making substantial progress in improving wound healing rates. It concludes with recommendations for improving the research and clinical knowledge base related to optimal wound-care practices.

Randomized controlled trial and cost-effectiveness analysis of silver-donating antimicrobial dressings for venous leg ulcers (VULCAN trial)

BACKGROUND

Antimicrobial silver dressings are used beneath graduated compression in the treatment of venous ulceration. There is little information on whether their use is effective. This was a prospective randomized trial and cost-effectiveness analysis of silver-donating versus non-silver low-adherence dressings in the treatment of venous leg ulcers.

METHODS

Patients were randomized between the two types of dressing. The primary outcome measure was complete ulcer healing at 12 weeks. Secondary outcomes included time to healing, quality of life and cost-effectiveness.

RESULTS

A total of 213 patients were recruited. There was no difference between the dressings in the proportion of ulcers healed at 12 weeks (59.6 per cent for silver and 56.7 per cent for control dressings). Mean utility scores for the EuroQol 5D and Short Form 6D were similar in both groups at 1, 3, 6 and 12 months. Compared with the control group the antimicrobial group had an incremental cost of pounds sterling 97.85 and an incremental quality-adjusted life year gain of 0.0002, giving an incremental cost-effectiveness ratio of pounds sterling 489 250 for the antimicrobial dressings.

CONCLUSION

No significant differences were found in either primary or secondary endpoints. There was no evidence to support the routine use of silver-donating dressings beneath compression for venous ulceration.

REGISTRATION NUMBER

ISRCTN 72485131 (http://www.controlled-trials.com).

[What's new in dermatological therapy?]

A review of the medical literature and of the regulatory agencies website was performed to identify new information about dermatological therapy from October 2006 to October 2007. Care was taken to prioritize results from randomized controlled trials and epidemiological studies of acceptable methodology. In the last year, significant advances have been made in the field of psoriasis, pemphigus, prevention of infection with oncogenic papillomaviruses, leg ulcers, evaluation of lasers and photodynamic therapy. The availability of biological agents for the treatment of psoriasis, auto-immune disease and skin cancer will certainly induce major changes in our therapeutic strategies in the near future. The dermatologist needs to keep-up with new therapies in order to address the therapeutic needs of patients with skin diseases.

How is research evidence used to support claims made in advertisements for wound care products?

AIMS AND OBJECTIVE

To investigate the amount, type and accuracy of citations use in support of product related claims from advertisements of wound care products.

BACKGROUND

Although articles submitted to most medical journals are subjected to peer review, such scrutiny is often not required for the content of advertisements.

DESIGN

A contents survey of advertisements from two wound care journals (Journal of Wound Care and Ostomy Wound Management) from 2002-2003 and the British Medical Journal, 2002-2003.

METHODS

Data collected from advertisements included identification of product related claims made and any corresponding citations. Where journal articles were cited to support claims, the articles were obtained. Where data on file were cited, this material was requested. In each case the accuracy of claims in relation to the content of the supporting citation was assessed.

RESULTS

The use of citations to support product related claims was infrequent in advertisements from wound care journals, where 35% of advertisements containing a product related claim also contained at least one citation, compared with 63% of advertisements from the British Medical Journal. Of citations that were supplied, journal articles were less common in the wound journals (40% vs. 73% in the British Medical Journal) and data on file more common (38% vs. 6% in the British Medical Journal). Where journal articles were obtained, 56% of claims in the wound care journals advertisements were not supported by the cited article, compared with 12% of claims in the British Medical Journal.

CONCLUSION

The wound journals advertised predominantly medical devices. The use and accuracy of referencing in advertisements from wound care journals was poor.

RELEVANCE TO CLINICAL PRACTICE

Nurses have increasing responsibilities for the prescribing of both drugs and devices, which must be accompanied by the ability to interpret marketing materials and research evidence critically. Nurse educators must ensure that nurse education generally and nurse prescriber training particularly, builds skills of information retrieval and critical appraisal.

Current therapeutic options of chronic leg ulcers

Wound treatment is continually becoming more complex and difficult. In the following review, we focus on the different options of wound debridement, stimulation of granulation tissue, different wound dressings, and therapeutic strategies in hard-to-heal-wounds. We also present some future treatment options for chronic wounds.

A review of the treatment for venous leg ulcers

Venous ulcers, sometimes termed varicose or stasis ulcers, are a consequence of damage to the valves in the veins of the legs, leading to raised venous pressure. They are characterized by a cyclical pattern of healing and recurrence. There is a need to have a thorough assessment of patients with leg ulcers by an appropriately experienced clinician to maximize the chance of healing the ulcer. The main treatment is the application of compression, either in the form of compression bandages or hosiery. Dressings are applied beneath the compression with a view to controlling exudate, comfort and to aid healing. There are a large number of dressing products and types available but the evidence to justify their use is poor. The main treatment for venous ulcers should therefore be the application of compression therapy with a simple, low adherent dressing.