An investigation of the benefits of Aquacel Hydrofibre wound dressing

Application of pulsed electric field technology to skin engineering

Tissue engineering encompasses a range of techniques that direct the growth of cells into a living tissue construct for regenerative medicine applications, disease models, drug discovery, and safety testing. These techniques have been implemented to alleviate the clinical burdens of impaired healing of skin, bone, and other tissues. Construct development requires the integration of tissue-specific cells and/or an extracellular matrix-mimicking biomaterial for structural support. Production of such constructs is generally expensive and environmentally costly, thus eco-sustainable approaches should be explored. Pulsed electric field (PEF) technology is a nonthermal physical processing method commonly used in food production and biomedical applications. In this review, the key principles of PEF and the application of PEF technology for skin engineering will be discussed, with an emphasis on how PEF can be applied to skin cells to modify their behaviour, and to biomaterials to assist in their isolation or sterilisation, or to modify their physical properties. The findings indicate that the success of PEF in tissue engineering will be reliant on systematic evaluation of key parameters, such as electric field strength, and their impact on different skin cell and biomaterial types. Linking tangible input parameters to biological responses critical to healing will assist with the development of PEF as a sustainable tool for skin repair and other tissue engineering applications.

Efficacy of Jiuzao polysaccharides in ameliorating alcoholic fatty liver disease and modulating gut microbiota

Jiuzao, the residue from Baijiu production, has shown radical scavenging properties in prior investigations, suggesting its potential as a hepatoprotective agent against acute liver damage. This study reveals that Jiuzao polysaccharides ameliorated liver morphological damage in zebrafish larvae afflicted with alcoholic fatty liver disease (AFLD), as evidenced by Oil red O, H&E, and Nile red staining. These polysaccharides notably modulated antioxidant enzyme levels and lipid peroxidation components. The real-time quantitative polymerase chain reactions analyses illustrated the significant impact of Jiuzao polysaccharides on genes integral to ethanol and lipid metabolism. The 16 S rRNA results showed that Jiuzao polysaccharides could improve the intestinal flora in zebrafish larvae exposed to ethanol. In summary, Jiuzao polysaccharides efficaciously mitigate liver lipid accumulation, enhance ethanol metabolism, and reduce oxidative stress by downregulating genes involved in AFLD development. They also regulate the changes in gut microbiota, providing further protection against acute alcoholic liver insult in zebrafish larvae.

Multi-disciplinary management of type 1 and 2 skin tears using a silver-based hydrofiber dressing

Skin tear is a common problem encountered in the emergency department. If it is not properly managed, it can lead to wound infection, skin necrosis and a need for further surgical intervention and skin grafting. Current management is to cleanse the wound, replace the thin skin tear followed by coverage with a dressing that is inducive for wound healing. Several dressings have been suggested for the coverage of these wounds. But, up to now, there has been no mention of the use of a silver-based hydrofiber dressing in the management of this condition. The objective of this study was to explore the use of a silver-based hydrofiber dressing for the management of paper-thin skin tears. We retrospectively reviewed all patients with Type 1 or 2 skin tears that had undergone management using a silver-based hydrofiber dressing between October 2019 and October 2020. Demographic data and medical history was obtained by retrospective chart review. Data that was collected included: age, sex, comorbid illnesses, defect location, defect size, complications, number of times the silver-based hydrofiber dressing was replaced and the number of days required to achieve complete wound healing. A total of 65 patients were included in the study. There were 42 males and 23 females. There were 28 patients whose age was greater then 85 years old, of which 14 patients were over 90 years old. The mean number of outpatient visits was 2. The mean defect size was 33 cm2 (range 1 cm × 1 cm to 18 × 10 cm). The mean number of days required for total wound healing was 13 days (range 7-21). We did not encounter any patients that required further surgical debridement or split-thickness skin grafting. The use of a silver-based hydrofiber dressing was well tolerated by the elderly population as it provided an easy, efficient, economical and effective form of management of skin tears. We suggest that a silver-based hydrofiber dressing can be used as a first-line treatment method for type 1 and 2 skin tears.

Evaluation of two fungal exopolysaccharides as potential biomaterials for wound healing applications

Microbial exopolysaccharides (EPSs) are mostly produced by bacteria and fungi and have potential use in the production of biomedical products such as nutraceuticals and in tissue engineering applications. The present study investigated the in vitro biological activities and in vivo wound healing effects of EPSs produced from a Sclerotium-forming fungus (Sclerotium glucanicum DSM 2159) and a yeast (Rhodosporidium babjevae), denoted as scleroglucan (Scl) and EPS-R, respectively. EPS yields of 0.9 ± 0.07 g/L and 1.11 ± 0.4 g/L were obtained from S. glucanicum and R. babjevae, respectively. The physicochemical properties of the EPSs were characterized using infrared spectroscopy and scanning electron microscopy. Further investigations of the biological properties showed that both EPSs were cytocompatible toward the human fibroblast cell line and demonstrated  hemocompatibility. Favorable wound healing capacities of the EPSs (10 mg/mL) were also established via in vivo tests. The present study therefore showed that the EPSs produced by S. glucanicum and R. babjevae have the potential use as biocompatible components for the promotion of dermal wound healing.

The performance of gelling fibre wound dressings under clinically relevant robotic laboratory tests

The effectiveness of wound dressing performance in exudate management is commonly gauged in simple, non‐realistic laboratory setups, typically, where dressing specimens are submersed in vessels containing aqueous solutions, rather than by means of clinically relevant test configurations. Specifically, two key fluid–structure interaction concepts: sorptivity—the ability of wound dressings to transfer exudate, including viscous fluids, away from the wound bed by capillary action and durability—the capacity of dressings to maintain their structural integrity over time and particularly, at removal events, have not been properly addressed in existing test protocols. The present article reviews our recent published research concerning the development of clinically relevant testing methods for wound dressings, focussing on the clinical relevance of the tests as well as on the standardisation and automation of laboratory measurements of dressing performance. A second objective of this work was to compile the experimental results characterising the performance of gelling fibre dressings, which were acquired using advanced testing methods, to demonstrate differences across products that apparently belong to the same “gelling fibre” family but differ remarkably in materials, structure and composition and, thereby, in performance.

Community setting survey evaluating AQUACEL dressings

OBJECTIVE

This study aimed to collect and analyse real-life data to characterise the initial use of Hydrofiber Technology dressings for the management of exuding wounds in France.

METHOD

An online survey of nurses provided data from patients managed with two dressings-AQUACEL Extra or AQUACEL Ribbon-as the primary dressing. At baseline, sociodemographic data, relevant medical histories and wound characteristics were recorded. The status of the wounds was then examined on days seven and 14 of management, together with scores of both clinician and patient satisfaction.

RESULTS

The survey included 1093 patients with a mean age of 65.9 years, comprising 53.3% women; 615 (56.3%) patients presented with acute wounds and 478 with hard-to-heal wounds. Wounds were reported to have healed or improved in 79.4% and 88.1% of the patients after 7 and 14 days, respectively. After 14 days, the wounds were smaller (p<0.001), and the percentage of sloughy wound bed tissue had decreased (p<0.001), while the percentage of granulation tissue and epithelialisation increased significantly (p=0.024 and p=0.047, respectively). Tolerance of the dressing was good, with low levels of pain reported, both while wearing the dressing and on removal. On day 14, nurses reported a high level of satisfaction, while 70% and 42.7% of patients with acute and hard-to-heal wounds, respectively, were 'very satisfied'.

CONCLUSION

The Hydrofiber Technology dressings aided wound healing when used in the management of a wide range of acute and hard-to-heal wounds in medical and surgical indications. User satisfaction was high from both healthcare professionals and patients.

Structure, preparation, modification, and bioactivities of β-glucan and mannan from yeast cell wall: A review

In order to solve the antibiotic resistance, the research on antibiotic substitutes has received an extensive attention. Many studies have shown that β-glucan and mannan from yeast cell wall have the potential to replace antibiotics for the prevention and treatment of animal diseases, thereby reducing the development and spread of antibiotic-resistant bacterial pathogens. β-Glucan and mannan had a variety of biological functions, including improving the intestinal environment, stimulating innate and acquired immunity, adsorbing mycotoxins, enhancing antioxidant capacity, and so on. The biological activities of β-glucan and mannan can be improved by chemically modifying its primary structure or reducing molecular weight. In this paper, the structure, preparation, modification, and biological activities of β-glucan and mannan were reviewed, which provided future perspectives of β-glucan and mannan.

Control Strategies for Infection Prevention in Total Joint Arthroplasty

Despite the development of newer preventative measures, the rate of infection continues to be approximately 1% for patients undergoing total joint arthroplasty (TJA). The extent of the infection can range from a mild superficial infection to a more serious periprosthetic joint infection (PJI). PJIs not only play a significant role in the clinical well-being of the TJA patient population, but also have substantial economic implications on the health care system. Several approaches are currently being used to mitigate the risk of PJI after TJA. The variety of prophylactic measures to prevent infection after TJA must be thoroughly discussed and evaluated.

The effect of wound dressings on infection following total joint arthroplasty

Background

The use of perioperative surgical wound dressings is an important factor in the mitigation of infection following total joint arthroplasty (TJA). Few studies have been published comparing wound dressings and infection rates after TJA.

Methods

MEDLINE, PubMed, and EMBASE were searched for studies published between 2006 and 2016 reporting infection rates in patients using various wound dressings after undergoing TJA. All studies comparing Hydrofibre dressings to Standard dressings or Absorbent dressings were included in this meta-analysis. Studies looking at TJA secondary to trauma were excluded. Two individuals independently extracted data, and study results were divided based on type of treatment. The primary outcome was to compare the infection rate of Hydrofibre dressings to that of both Standard Dressings and Absorbent dressings.

Results

Of a total of 3721 participants, 1483 were treated with Standard dressings (non-impregnated gauze), 1911 with Hydrofibre dressings, and 327 with Absorbent dressings. The risk ratio for infection comparing Standard with Hydrofibre was 4.16 (95% confidence interval, 1.71-10.16) as compared to 2.60 (95% confidence interval, 0.66-10.27) when comparing Absorbent with Hydrofibre dressings.

Conclusions

Our analysis suggests that Hydrofibre dressings may be significantly better than Standard and Absorbent dressings with respect to reducing infection. However, given the observed heterogeneity and small number of studies included, more comparative studies are needed to definitively recommend superiority among dressings following TJA.

Level of Evidence

Level 1.

Hydrofiber Dressing Saturated With Mafenide Acetate Extends the Duration of Antimicrobial Activity

Mafenide acetate is used in some burn wounds for its ability to penetrate eschar but requires frequent uncomfortable dressing changes for its application. The authors hypothesize that hydrofiber dressings will hold mafenide acetate solution for an extended period of time and maintain antimicrobial activity longer than traditional gauze, thus possibly obviating the need for frequent dressing changes. Four experimental arms included: 1) hydrofiber, stored on a dry well plate as control, 2) gauze saturated with 2.5% mafenide acetate, stored on nonsterile porcine skin, 3) hydrofiber saturated with mafenide acetate, stored on dry well plate, and 4) hydrofiber saturated with mafenide acetate, stored on nonsterile porcine skin. At 0, 24, 48, and 72 hours, a 1-cm disk was cut from the dressing sheet of each study arm, placed on agar plates seeded with Staphylococcus aureus and Pseudomonas aeruginosa, and incubated for 24 hours, and the zone of inhibition was measured. A zone of 2 mm or greater was indicative of susceptibility. Each arm of the experiment was performed four times to demonstrate reproducibility. Plain hydrofiber (control) demonstrated no zone of inhibition at any time point, thereby possessing no antimicrobial activity alone. Gauze saturated with mafenide acetate did not reliably demonstrate antimicrobial activity beyond 0 hours. Hydrofiber saturated with mafenide acetate, whether stored on a dry well plate or nonsterile porcine skin, consistently possessed sustained antimicrobial activity as demonstrated by zones of inhibition greater than 2 mm to both S. aureus and P. aeruginosa. Mafenide acetate-soaked hydrofiber dressings stay moist and maintain antimicrobial activity against S. aureus and P. aeruginosa for at least 72 hours without repeated soaks.

Clinical safety and effectiveness evaluation of a new antimicrobial wound dressing designed to manage exudate, infection and biofilm

The objective of this work was to evaluate the safety and effectiveness of a next-generation antimicrobial wound dressing (NGAD; AQUACEL^® Ag+ Extra™ dressing) designed to manage exudate, infection and biofilm. Clinicians were requested to evaluate the NGAD within their standard protocol of care for up to 4 weeks, or as long as deemed clinically appropriate, in challenging wounds that were considered to be impeded by suspected biofilm or infection. Baseline information and post-evaluation dressing safety and effectiveness data were recorded using standardised evaluation forms. This data included wound exudate levels, wound bed appearance including suspected biofilm, wound progression, skin health and dressing usage. A total of 112 wounds from 111 patients were included in the evaluations, with a median duration of 12 months, and biofilm was suspected in over half of all wounds (54%). After the introduction of the NGAD, exudate levels had shifted from predominantly high or moderate to low or moderate levels, while biofilm suspicion fell from 54% to 27% of wounds. Wound bed coverage by tissue type was generally shifted from sloughy or suspected biofilm towards predominantly granulation tissue after the inclusion of the NGAD. Stagnant (65%) and deteriorating wounds (27%) were shifted to improved (65%) or healed wounds (13%), while skin health was also reported to have improved in 63% of wounds. High levels of clinician satisfaction with the dressing effectiveness and change frequency were accompanied by a low number of dressing-related adverse events (n = 3; 2·7%) and other negative observations or comments. This clinical user evaluation supports the growing body of evidence that the anti-biofilm technology in the NGAD results in a safe and effective dressing for the management of a variety of challenging wound types.

Wound dressings for primary and revision total joint arthroplasty

BACKGROUND

Preventing post-surgical complications after total joint arthroplasty (TJA) is of great importance, and application of an appropriate wound dressing is necessary. Since no dressing encompasses all the parameters required for ideal wound healing, a comparison of the available dressing types can assist the surgeon to choose the best dressing after TJA.

METHODS

Studies evaluating postoperative wound dressings after TJA were reviewed in order to assess the outcomes, complications and costs associated with dressing types.

RESULTS

Traditional cotton dressings have a high ability to absorb exudate. However, they dry out sooner and there is a risk of pain and additional trauma during dressing changes. Although vapor permeable dressings allow transmission of moisture, but they have low absorptive capacity and require frequent changes even with moderately exudating wounds. On the other hand, hydrofiber and hydrocolloid dressings have high absorptive capacity and permeability, and can cope with exudate production. They are changed less often and have low blistering rates, which may reduce surgical site infection (SSI). Although the unit cost associated with advanced dressings is much higher than the traditional dressings, the decreased rate of periprosthetic joint infection (PJI) and the cost associated with treating PJI more than compensate for it.

CONCLUSIONS

Choice of dressing type after TJA should depend upon permeability, absorptive capacity, documented rate of SSI and cost effectiveness with its use, apart from a surgeon's past clinical experience and familiarity.

Multi-scale mechanical characterization of highly swollen photo-activated collagen hydrogels

Biological hydrogels have been increasingly sought after as wound dressings or scaffolds for regenerative medicine, owing to their inherent biofunctionality in biological environments. Especially in moist wound healing, the ideal material should absorb large amounts of wound exudate while remaining mechanically competent in situ. Despite their large hydration, however, current biological hydrogels still leave much to be desired in terms of mechanical properties in physiological conditions. To address this challenge, a multi-scale approach is presented for the synthetic design of cyto-compatible collagen hydrogels with tunable mechanical properties (from the nano- up to the macro-scale), uniquely high swelling ratios and retained (more than 70%) triple helical features. Type I collagen was covalently functionalized with three different monomers, i.e. 4-vinylbenzyl chloride, glycidyl methacrylate and methacrylic anhydride, respectively. Backbone rigidity, hydrogen-bonding capability and degree of functionalization (F: 16 ± 12–91 ± 7 mol%) of introduced moieties governed the structure–property relationships in resulting collagen networks, so that the swelling ratio (SR: 707 ± 51–1996 ± 182 wt%), bulk compressive modulus (E_c: 30 ± 7–168 ± 40 kPa) and atomic force microscopy elastic modulus (E_AFM: 16 ± 2–387 ± 66 kPa) were readily adjusted. Because of their remarkably high swelling and mechanical properties, these tunable collagen hydrogels may be further exploited for the design of advanced dressings for chronic wound care.

Wound care in venous ulcers

Wound dressings: ulcer dressings should create and maintain a moist environment on the ulcer surface. It has been shown that in an ulcer with a hard crust and desiccated bed, the healing process is significantly slowed and sometimes completely blocked so favouring infection, inflammation and pain. In contrast a moist environment promotes autolytic debridement, angiogenesis and the more rapid formation of granulation tissue, favours keratinocytes migration and accelerates healing of wounds. Apart from these common characteristics, wound dressings are completely different in other aspects and must be used according to the ulcer stage. In necrotic ulcers, autolytic debridement by means of hydrogel and hydrocolloids or with enzymatic paste is preferred. In case of largely exuding wounds alginate or hydrofibre are indicated. When bleeding occurs alginate is indicated due to its haemostatic power. Where ulcers are covered by granulation tissue, polyurethane foams are preferred. When infection coexists antiseptics are necessary: dressing containing silver or iodine with large antibacterial spectrum have proved to be very effective. In the epithelization stage polyurethane films or membranes, thin hydrocolloids or collagen based dressings are very useful to favour advancement of the healing wound edge. Despite these considerations, a Cochrane review failed to find advantages for any dressing type compared with low-adherent dressings applied beneath compression. Surgical debridement and grafting of wounds, negative wound pressure treatment: surgical and hydrosurgical debridement are indicated in large, necrotic and infected wounds as these treatments are able to get rid of necrotic, infected tissue very quickly in a single surgical session, thereby significantly accelerating wound bed preparation and healing time. Negative wound pressure treatment creating a negative pressure on ulcer bed is able to favour granulation tissue and shorten healing time. In case of hard-to-heal leg ulcers such as large, deep, infected and long-lasting venous ulcers, sharp debridement and skin grafting may favour and shorten ulcer healing.

Moist occlusive dressing (Aquacel(®) Ag) versus moist open dressing (MEBO(®)) in the management of partial-thickness facial burns: a comparative study in Ain Shams University

INTRODUCTION

The face is the central point of the physical features; it transmits expressions and emotions, communicates feelings and allows for individual identity. Facial burns are very common and are devastating to the affected patient and results into numerous physical, emotional and psychosocial sequels. Partial thickness facial burns are very common especially among children. This study compares the effect of standard moist open technique management and a moist closed technique for partial thickness burns of the face.

PATIENTS AND METHODS

Patients with partial-thickness facial burns admitted in the burn unit, Ain Shams University, Cairo, Egypt in the period from April 2009 to December 2009 were included in this study. They were divided into two groups to receive either open treatment with MEBO(®) (n=20) or coverage with Aquacel(®) Ag (n=20). Demographics (age, gender, ethnicity, TBSA, burn areas), length of hospital stay (LOS), rate of infections, time to total healing, frequency of dressing changes, pain, cost benefit and patient discomfort were compared between the two groups. The long-term outcome (incidence of hypertrophic scarring) was assessed for up to 6 months follow-up period.

RESULTS

There were no significant differences in demographics between the two groups. In the group treated with the Aquacel(®) Ag, the mean time for re-epithelialization was 10.5 days, while it was 12.4 days in the MEBO(®) group (p<0.05). Frequency of changes, pain and patient discomfort were less with Aquacel(®) Ag. Cost was of no significant difference between the two groups. Scar quality improved in the Aquacel(®) Ag treatment group. Three and 6 months follow-up was done and long-term outcomes were recorded in both groups.

CONCLUSION

Moist occlusive dressing (Aquacel(®) Ag) significantly improves the management and healing rate of partial thickness facial burns with better long-term outcome compared to moist open dressing (MEBO(®)).

The management of wounds following primary lower limb arthroplasty: a prospective, randomised study comparing hydrofibre and central pad dressings

Wound care following lower limb arthroplasty has not been subject to in-depth clinical research, primarily because such wounds usually heal without complication. However, when prosthetic implants are used, serious wound problems can be disastrous (Whitehouse et al. Infect Control Hosp Epidemiol 2002;23:183-9; Lindwell OM. Clin Orthop Relat Res 1986;211:91-103). We report the results of a prospective, randomised, controlled trial comparing a hydrofibre (Aquacel) and central pad (Mepore) dressing in the management of acute wounds following primary total hip or knee arthroplasty left to heal by primary intention. Dressing performance was measured in 61 patients receiving total hip or knee replacements. There was a significant reduction in the requirement for dressing changes before five postoperative days in the hydrofibre group (43% compared with 77% in the central pad group), and there were fewer blisters amongst patients in the hydrofibre group (13% compared with 26% in the central pad group). We conclude that there is a potential role for hydrofibre dressing in the management of arthroplasty wounds.

Prevention and management of pressure ulcers

Pressure ulcers represent a major health problem causing a considerable amount of suffering for patients and a high financial burden for healthcare systems. The geriatric population with an increased risk of pressure ulcer development is rising constantly as a result of chronic degenerative diseases that can lead to prolonged immobilization and poor nutrition. Evidence clearly indicates that preventive measures are essential to reduce the prevalence rates of pressure ulcers; therefore healthcare professionals must be able to identify the appropriate strategies to adopt, in order to meet the individual patient's requirements. Important advances have taken place in the world of pressure ulcer treatment during the past decade. These advances are reflected in the high rate of cures being obtained. This, together with the implementation of prevention guidelines, the excellent cost/effectiveness relationship of the techniques described, and other factors, means that the field of pressure ulcers management is no more an isolated and self-administered issue in medical practice. The areas discussed here are those in which there will be linear or, in some cases, exponential growth in the decades to come.

The effect of a silver-containing Hydrofiber dressing on superficial wound bed and bacterial balance of chronic wounds

The treatment of chronic wounds represents a major cost to society and has a profound effect on the participant's quality of life. Chronic wounds may have an increased bacterial burden that can impair healing without all the clinical signs of infection. Silver dressings may provide an alternative topical method to control bacterial burden. The primary aim of this study was to evaluate the clinical improvement in chronic wounds through the effect on wound size, maceration, resolution of surface slough and conversion to healthy granulation during a 4-week application of the silver-containing Hydrofiber dressing. This was a single centre, open-label case series study which included a total of 30 evaluable participants: four with diabetic neuropathic foot ulcers, 13 venous stasis ulcers, four pressure ulcers and nine miscellaneous wounds that did not fit any of the previous categories. All participants had adequate vascular supply, indicating the potential to heal. The wounds were stalled or had the signs and symptoms consistent with critical colonisation. The underlying cause of the ulceration was identified and corrected, or the symptoms and signs were treated. This was followed by the application of silver-containing Hydrofiber dressings for a period of 4 weeks. The majority of wounds treated decreased in size (70%) with decreased exudate, decreased purulence and resolution of surface slough (75%). There was an increased quality and quantity of healthy granulation tissue. Unlike some silver dressings, the Hydrofiber and silver combination dressing was unlikely to cause burning and stinging on application. Peri-wound maceration was present in 54% of participants at baseline, and 85% of these resolved with this dressing. A desloughing action was seen in those patients with pre-existing slough at baseline and its removal will lower the bacterial burden of the wound.

Comparison of bacteria-retaining ability of absorbent wound dressings

Fibrous materials in some modern absorbent wound dressings have the ability to sequester and retain bacteria; however, this ability varies according to the nature of the fibres. We studied the bacterial retention capacity of alginate and carboxymethylcellulose dressings, using an infected skin ulcer model on the backs of rats. Wound surfaces were inoculated with either Staphylococcus aureus or Pseudomonas aeruginosa at a concentration of 1.5 x 10(6) colony-forming units per wound. AQUACEL; Hydrofiber;, Kaltostat; or Sorbsan; were applied to the contaminated wounds for 12 h. Each dressing was then divided into two pieces. Total viable bacterial count within the dressing was calculated using one piece, and bacterial count released from the dressing into physiological saline was determined using the other piece, enabling bacterial retention rate to be calculated. Bacterial counts in tissue were also determined. Each dressing was tested on each of 10 wounds contaminated with each bacterium. Statistical analyses were performed using one-way analysis of variance (ANOVA) for replicated measures combined with Duncan's multiple comparison test. AQUACEL; Hydrofiber; dressing was most effective in its ability to retain both Staphylococcus aureus and Pseudomonas aeruginosa (p < 0.05). Bacterial counts in tissue showed no significant change with respect to pathogen or the type of dressing used. It can be concluded that the bacterial retaining ability of AQUACEL; Hydrofiber; dressing was found to be significantly higher than that of alginate dressings in an infected animal wound model.

A prospective, randomised, controlled trial comparing wound dressings used in hip and knee surgery: Aquacel and Tegaderm versus Cutiplast

INTRODUCTION

Cutiplast (absorbent perforated dressing with adhesive border; Smith & Nephew) is commonly used following orthopaedic operation, but complications of its use have been reported. A prospective, randomised, controlled study was performed to compare the efficacy of Cutiplast versus an Aquacel (hydrofibre dressing; ConvaTec) covered with Tegaderm (vapour-permeable dressing; 3M).

PATIENTS AND METHODS

Two-hundred patients were randomised to receive one of the two dressings following elective and non-elective surgery of the hip and the knee. We were able to study 183 patients. The condition of the wound and any complications such as skin blistering or signs of infection was noted as was the frequency of dressing changes.

RESULTS

The Aquacel and Tegaderm dressing was 5.8 times more likely to result in a wound with no complications as compared to a Cutiplast dressing (odds ratio, 5.8; 95% CI 2.8-12.5; P < 0.00001).

CONCLUSION

Aquacel covered by Tegaderm is a superior dressing to Cutiplast following surgery to the hip and knee.

Assessment and management of fungating wounds: a review

Fingating wounds always present a management challenge. Not only is it often difficult to manage the physical aspects of the wound - pain, bleeding, exudate and odour - but also the psychological impact of a fungating wound on the patient and their family or carers is often considerable. This review examines current practice in relation to fungating wounds, and emphasizes the central important of assessment, communication and sensitivity in nursing management.

New and experimental approaches to treatment of diabetic foot ulcers: a comprehensive review of emerging treatment strategies

Diabetic foot ulcers occur in up to 15% of all diabetic patients and are a leading cause of nontraumatic amputation worldwide. Neuropathy, abnormal foot biomechanics, peripheral vascular disease and external trauma are the major contributors to the development of a foot ulcer in the diabetic patient. Therapy today includes repeated debridement, offloading, and dressings, for lower grade ulcers, and broad spectrum antibiotics and occasionally limited or complete amputation for higher grades, requiring a team effort of health care workers from various specialties. The large population affected by diabetic foot ulcers and the high rates of failure ending with amputation even with the best therapeutic regimens, have resulted in the development of new therapies and are the focus of this review. These include new off loading techniques, dressings from various materials, methods to promote wound closure using artificial skin grafts, different growth factors or wound bed modulators and methods of debridement. These new techniques are promising but still mostly unproven and traditional approaches cannot be replaced. New and generally more expensive therapies should be seen as adding to traditional approaches.

Controlling wound bioburden with a novel silver-containing HydrofiberR dressing

Clinicians now recognize that both aerobic and anaerobic microorganisms have the ability to degrade or damage host tissue at a wound site through the production of a variety of enzymes and toxins. Silver-containing dressings offer one method for controlling this polymicrobial wound bioburden, and research efforts are currently ongoing to determine their efficacy against aerobic, anaerobic, and antibiotic-resistant microorganisms. The current study aimed to determine the antimicrobial activity of a new silver-containing Hydrofiber dressing (AQUACEL Ag) on both aerobic and anaerobic microorganisms, using the zone-of-inhibition method. This method provides a measure of the ability of the dressing to make available a sufficient concentration of silver to have an antimicrobial effect. To some extent this test mimics the clinical use of the dressing and predicts its microbicidal activity at the wound-dressing interface. The results show that the silver-containing dressing makes silver available at a dressing-agar interface at a concentration that is effective against a broad range of aerobic, anaerobic, and antibiotic-resistant microorganisms. In the context of wound healing, the results showing antimicrobial activity against antibiotic-resistant microorganisms are particularly important, as the control and eradication of these organisms is a major concern within the health care profession.

Comparison of the antioxidant properties of wound dressing materials--carboxymethylcellulose, hyaluronan benzyl ester and hyaluronan, towards polymorphonuclear leukocyte-derived reactive oxygen species

In chronic wounds, factors are released which perpetuate inflammatory processes, including polymorphonuclear leukocyte (PMN)-derived reactive oxygen species (ROS), such as superoxide radical (O(2)*-) and hydroxyl radical (*OH) species. The glycosaminoglycan, hyaluronan, has established antioxidant properties towards ROS, although the antioxidant potential of wound dressing biomaterials, such as 75% benzyl esterified hyaluronan (BEHA) and carboxymethylcellulose (CMCH), are less characterised. This study compared the antioxidant properties of high and low molecular weight hyaluronan (HMWT HA and LMWT HA), BEHA and CMCH towards ROS, generated by stimulated PMN in vitro. The antioxidant capacities of each biomaterial were assessed by their inhibition of O(2)*- -induced cytochrome C reduction, generated via PMN stimulation by phorbol myristyl acetate (PMA); and their inhibition of *OH-induced 2-deoxy-D-ribose degradation, generated by PMA stimulated PMN in the presence of a ferric chloride-EDTA chelate. All biomaterials, except LMWT HA, possessed dose-dependent antioxidant properties against O(2)*-, BEHA having greatest antioxidant potential, followed by HMWT HA and CMCH. HMWT HA exhibited the highest dose-dependent antioxidant properties towards *OH, followed by BEHA and CMCH. LMWT HA demonstrated no antioxidant properties towards *OH. These antioxidant activities, particularly towards O(2)*-, may be beneficial in removing the initial source of ROS necessary for the secondary formation of *OH, implicated as a causal factor for the extensive metabolic alterations observed in chronic wounds.

Comparison of the antioxidant properties of HYAFF-11p75, AQUACEL and hyaluronan towards reactive oxygen species in vitro

In chronic wounds, a number of host factors are released which perpetuate the inflammatory process, including polymorphonuclear leukocyte (PMN)-derived reactive oxygen species (ROS), such as superoxide radical (O2*-) and hydroxyl radical (*OH) species. The glycosaminoglycan. hyaluronan, has been shown to act as an antioxidant towards ROS, although the potential for biomaterials, such as HYAFF -11p75 (the 75% benzyl ester of hyaluronan) and AQUACEL (carboxymethylcellulose), to act in this manner has yet to be elucidated. This study compared the antioxidant properties of high and low molecular weight hyaluronan (HMWT HA and LMWT HA), HYAFF -11p75, AQUACEL and an AQUACEL /hyaluronan composite (AQUACEL /HA) against O2*- and *OH. The antioxidant capacities of each material were assessed by their ability to inhibit cytochrome C reduction by O2*- fluxes, generated via the oxidation of hypoxanthine by xanthine oxidase, and their inhibition of 2-deoxy-D-ribose degradation by *OH fluxes, generated by the reaction of hydrogen peroxide (H2O2) and iron (Fe2+). All materials studied possessed dose dependent antioxidant properties towards O2*-, with HYAFF 11p75 having the greatest antioxidant potential towards these species, followed by AQUACEL, HMWT HA, AQUACEL /HA and LMWT HA. Only HMWT HA exhibited dose dependent antioxidant properties towards *OH at the fluxes examined. Gas chromatography/mass spectrometry analysis implied that ester bonds between the hyaluronan backbone and benzyl groups of HYAFF -11p75 are highly susceptible to O2*- hydrolysis, with the de-esterified benzyl alcohol being rapidly degraded in the presence of *OH. This data supports the hypothesis that HYAFF -11p75 has greater antioxidant capacity towards O2*-, due to the esterified benzyl groups providing alternative sites for O2*- attack other than the hyaluronan backbone of HYAFF -11p75 itself and explains the inability of HYAFF -11p75 to scavenge *OH, due to benzyl alcohol degradation by *OH. The antioxidant activities of these biomaterials, particularly HYAFF -11p75 and AQUACEL, towards O2*- could be beneficial, as the scavenging of PMN-derived O2*- may remove initial sources of O2*- and further prevent the secondary formation of *OH. These ROS are thought to be a primary causal factor for the extensive degradation and metabolic alterations observed in chronic wounds.

Physico-chemical characterisation of carboxymethylated spun cellulose fibres

A new fibrous material for the treatment of exudative wounds is characterised in terms of its physico-chemical properties. The chemistry of the material is analysed and its crystalline structure hypothesised. The influence of the structure on the hydration properties of the carboxymethylated cellulose fibre in fabric form is also demonstrated by physical test methods in comparison with fibrous alginate dressings. The methods illustrate the ability of the material to immobilise fluid by gel blocking and suggest how this can be beneficial in the treatment of chronic wounds by protecting the delicate peri-ulcer area from maceration by exudate.