Types Of Wound Dressings Research Articles

Bacterial Growth Kinetics under a Novel Flexible Methacrylate Dressing Serving as a Drug Delivery Vehicle for Antiseptics

A flexible methacrylate powder dressing (Altrazeal®) transforms into a wound contour conforming matrix once in contact with wound exudate. We hypothesised that it may also serve as a drug delivery vehicle for antiseptics. The antimicrobial efficacy and influence on bacterial growth kinetics in combination with three antiseptics was investigated in an in vitro porcine wound model. Standardized in vitro wounds were contaminated with Staphylococcus aureus (MRSA; ATCC 33591) and divided into six groups: no dressing (negative control), methacrylate dressing alone, and combinations with application of 0.02% Polyhexamethylene Biguanide (PHMB), 0.4% PHMB, 0.1% PHMB + 0.1% betaine, 7.7 mg/mL Povidone-iodine (PVP-iodine), and 0.1% Octenidine-dihydrochloride (OCT) + 2% phenoxyethanol. Bacterial load per gram tissue was measured over five days. The highest reduction was observed with PVP-iodine at 24 h to log10 1.43 cfu/g, followed by OCT at 48 h to log10 2.41 cfu/g. Whilst 0.02% PHMB resulted in a stable bacterial load over 120 h to log10 4.00 cfu/g over 120 h, 0.1% PHMB + 0.1% betaine inhibited growth during the first 48 h, with slightly increasing bacterial numbers up to log10 5.38 cfu/g at 120 h. These results indicate that this flexible methacrylate dressing can be loaded with various antiseptics serving as drug delivery system. Depending on the selected combination, an individually shaped and controlled antibacterial effect may be achieved using the same type of wound dressing.

Locally Produced Microbial Cellulose Dressing from Acetobacter xylinum Compared with Silver Sulfadiazine Cream for Patients with Acute Superficial Partial Thickness Burn Wounds: A Randomized Controlled Trial

Objective: To compare the efficacy and safety of microbial cellulose (MCD) dressing from Acetobacter xylinum in promoting healing of superficial partial thickness burn wounds to standard dressing using silver sulfadiazine (SSD) cream and gauze in terms of the following: time to healing, pain score, scarring and infection rate. Population: Subjects included patients seen at the ATR Burn Center UP-PGH from February 2008 to December 2010. Patients were 18- 50 years of age with<40% TBSA, acutely injured (≤ 48 hours) and with no uncontrolled medical condition. Pregnant patients were excluded. Methods: Each subject served as his own control, wherein burn wounds were randomized into 2 types of wound dressing. Wounds were assessed by a lone plastic surgeon blinded to all treatments. Results: Forty-five patients who fulfilled the inclusion criteria were seen and treated at the ATR Burn Center of the UP-PGH. Wounds dressed with MCD healed more rapidly compared to those dressed with SSD. The mean healing days were 8.51 and 12.07 for MC and SSD (P<0.05). Only 29 subjects were able to return on the 30th post burn day for assessment of scarring. Conclusion: Locally produced MCD is more efficacious compared to SSD in the treatment of SPT burns in terms faster healing and lower VAS scores. Key words: superficial partial thickness burn, Acetobacter xylinum

Comparative study of the antibacterial penetrating effects of wound dressings

In an infected wound, bacteria are present not only on the surface but also within the granulation tissue. The presence of bacteria inside the granulation tissue is one of the reasons for our inability to control infection. We have developed an in vitro model of an infected wound using Luria-Bertani (LB) agar media and non-pathogenic Escherichia coli, and compared the differences in the antibacterial effects of various types of antibacterial wound dressings. The results have shown that the penetrating antibacterial effects differed according to the type of wound dressing selected. As the thickness of the layer of the LB agar media increased, the potency of antibacterial effects caused by penetration decreased. In conclusion, it was suggested that antibacterial wound dressings can have antibacterial effects against bacteria not only on the surface of an infected wound but inside, so it is necessary to use different wound dressings according to the conditions of each infected wound.

Angelica sinensis isolate SBD.4: composition, gene expression profiling, mechanism of action and effect on wounds, in rats and humans

This report characterizes an aqueous isolate (SBD.4) of one of the most broadly used Chinese medicinal herbs, Angelica sinensis, from the perspective of its application in skin and wound care. SBD.4 has been chemically defined and was found to increase the strength of healed wounds in retired breeder (older) rats. Furthermore, the mechanism of action of this Angelica sinensis isolate was tested in the zebrafish angiogenesis model, and in human skin substitutes by DNA microarray, revealing a bioactivity profile consistent with skin repair and regeneration. When combined with several types of wound dressings, SBD.4 increased type I collagen production in human dermal fibroblasts, and when formulated in nanosilver hydrocolloid dressing, it was found effective in chronic ulcer management in humans, demonstrating that botanical high-tech wound dressings can be successfully developed to improve the treatment of chronic lesions in humans.

Investigation of adhesion of modern wound dressings: a comparative analysis of 56 different wound dressings

In the process of chronic wound care, adhesive wound dressings may cause pain and injury in the wound environment during dressing changes. At present, no standardized test procedures are available for the investigation of adhesion of wound dressings. Therefore, our study aimed to test the adhesion of different wound dressings on steel as well as on healthy skin. Within an open, comparative study, the adhesive areas of 56 wound dressings were investigated. The adhesives were categorized into acrylate (n = 23), silicone (n = 9), hydrocolloid (n = 17) and polyurethane groups (n = 7). Using an especially modified testing machine, the adhesion of the wound dressings was measured on steel as well as on the skin of healthy study participants, in compliance with the European EN 1939:2003 standard. The energy required to remove the wound dressings from human skin, was measured in Newton (N) and the following median values were obtained: hydrocolloid (2.25 N) > acrylate (1.14 N) > polyurethane (0.9 N) > silicone (0.7 N). The subjective pain intensity during the removal of the wound dressings was recorded using the visual analogue scale (VAS) with values ranging from 0 to 10. For hydrocolloid, it was 6.8, for acrylate 4.9, for polyurethane 3.1 and for silicone 2.5 points VAS. In comparison with human skin, the adhesion of wound dressings was significantly higher on steel (P < 0.0001), but was different for the different groups of wound dressings. Moreover, there was a statistically significant correlation between the adhesion and pain intensity (correlation coefficient 0.806; P = 0.01). The knowledge about the widely differing adhesion properties of different wound dressings on the skin of patients should nowadays be considered during the individual selection of the applied products. Based on these data, different types of wound dressings could be developed, guaranteeing a good adhesion and a low traumatic risk when removed.

Wound Dressings Update

ABSTRACTThe availability of different types of wound dressings has increased in the last decade. Wound care practitioners have at their disposal an extensive range of dressings. Emerging dressing types include interactive/bioactive dressings and tissue‐engineered skin substitutes. There is no one dressing that is suitable for the management of all types of chronic wounds and few are suited for the treatment of a single wound during all stages of the healing cycle. Successful wound management depends on an understanding of the healing process combined with knowledge of the properties of the various dressings available. Without such knowledge and careful assessment of all the factors that effect healing, dressing selection is likely to be arbitrary and ineffective, wasteful both in terms of time and physical resources. This article is an overview of some of the first‐line and second‐line interactive/bioactive dressings available. A synopsis of wound assessment and wound bed preparation will aid in choosing the appropriate dressings. It will also touch on advanced technologies including tissue‐engineered skin substitutes.

In vitro method to assess the antimicrobial activity and potential efficacy of novel types of wound dressings

To develop a simple, reproducible in vitro static diffusion method using cellulose disks and defined species to test antimicrobial efficacy of wound dressings. Cellulose disks were inoculated by immersion in cell suspensions of target species Staphylococcus epidermidis, Candida albicans and Fusobacterium nucleatum. Test and control wound dressings were cut into equal sized squares (25 x 25 mm) and applied to the surface of 10-mm thick tryptone yeast extract agar on test beds. Following a 2-h equilibration period, inoculated cellulose disks were inserted (one per dressing) at the interface between dressing and agar surface and a small weight applied over each square. At various sampling times, disks were removed and surviving cells enumerated by viable counts. Disk to disk variation for microbial loading was assessed using S. epidermidis for both initial (n = 16) and standard treatment (n = 16) conditions. The coefficient of variation was low (<5%) indicating good reproducibility for cell loading and treatment position on the test bed. Replicate assays (n = 6) using S. epidermidis and oxyzyme gels produced similar kill rates with low scatter (R2 > 0.9) indicating good reproducibility between assays. Significant differences (P < 0.05) in kill rates were observed for different target species, types of dressing and test bed conditions (+/-blood and nutrients). The method is reproducible and useful in tracking the death kinetics of test species, enabling the comparison of different types of dressing. The reported method has significant advantages over established test procedures; it can be applied equally across a wide range of target species (including anaerobes and yeasts), a wide range of conditions, and different types of surface dressings, including those relying upon oxygen diffusion.

Wounds scrutiny in a Swedish hospital: prevalence, nursing care and bacteriology, including MRSA

To identify all wounds, wound types and wound characteristics; to identify bacteria in all wounds, particularly MRSA, VRE and multi-resistant Gram-negative rods;. All patients admitted to or visiting hospital clinics were examined. If the patient had a wound, a questionnaire was filled in by a nurse, and if the wound met the inclusion criteria swabs were taken. A total of 2172 patients were admitted to or visited the hospital; 408 (19%) had a total of 668 wounds. Of this number, 248 were cultured. Thirty-seven patients had pressure ulcers, 83 had leg and foot ulcers and 288 patients had other types of wounds. Nursing care varied according to wound type and ward. Fifty-eight different types of wound dressings were used. Cleansing was performed with saline in 58% of the wounds. The mean number of dressing changes was once daily. Wounds were painful in 37% of the cases, with a predominance of leg and foot ulcers (51%). Many patients did not receive analgesia. MRSA was identified in two patients. No VRE was identified, and there was a low prevalence of multi-resistance in Enterobacteriaceae and Pseudomonas aeruginosa. The study provided important information for future improvement of wound care in a university hospital. Fewer resistant bacteria, particularly MRSA, were identified than expected.

Chronic venous insufficiency and venous leg ulceration

Venous ulcers are the most common form of leg ulcers. Venous disease has a significant impact on quality of life and work productivity. In addition, the costs associated with the long-term care of these chronic wounds are substantial. Although the exact pathogenic steps leading from venous hypertension to venous ulceration remain unclear, several hypotheses have been developed to explain the development of venous ulceration. A better understanding of the current pathophysiology of venous ulceration has led to the development of new approaches in its management. New types of wound dressings, topical and systemic therapeutic agents, surgical modalities, bioengineered tissue, matrix materials, and growth factors are all novel therapeutic options that may be used in addition to the “gold standard,” compression therapy, for venous ulcers. This review discusses current aspects of the epidemiology, pathophysiology, clinical presentation, diagnostic assessment, and current therapeutic options for chronic venous insufficiency and venous ulceration. (J Am Acad Dermatol 2001;44:401-21.)Learning objective: At the conclusion of this learning activity, participants should be familiar with the 3 main types of lower extremity ulcers and should improve their understanding of the epidemiology, pathogenesis, risk factors, clinical presentation, diagnostic assessment, and current therapies for chronic venous insufficiency and venous ulcers.

A one hospital study of the effect of wound dressings and other related factors on skin blistering following total hip and knee arthroplasty

Skin blisters occur when the epidermis is separated from the dermis. This occurs as a result of continued friction. Blisters occurring lateral to the surgical incision of patients following orthopaedic surgery have been observed for many years. There is, however, a lack of empirical evidence indicating the causation of wound blistering. The aim of the study was to identify the prevalence of wound blistering within a specialist orthopaedic hospital, and in addition to determine the cause(s). A quasi-experimental design was used to investigate the prevalence and causation of wound blistering with a convenience sample of 169 patients following primary total hip and knee replacement. Data were collected at four time intervals to assess if wound blistering had occurred between surgery and 72 h post-operatively. The data were recorded on a specially designed form, completed by a registered nurse at the four interval points. Data were collected on type of dressing used, presence of blisters around the wound site with initial data collected on known allergies, use of steroids and type of skin preparation used during the procedure. The data were then analysed using Chi-square test to ascertain if significant statistical differences existed between formation of blisters and a number of independent variables including: type of wound dressing, type of surgical skin preparation used, use of steroids and patients having known allergies. From the sample (n=169), 22 patients (13%) developed blistering. No statistically significant difference was found between any of the independent variables (P value 0.05). It is, however, noteworthy that only 8 of the patients with ‘Opsite Post Op’ (n=88) developed blisters compared to 4 of the 28 patients who had a ‘Mepore’ dressing. This would appear to affirm earlier findings that stated that lack of elasticity of dressings coupled with postoperative wound oedema is a contributing factor to formation of wound blistering. In addition, the nursing staff reported that they found Opsite Post Op dressing easy to apply and remove compared to other types of dressings available.

Hydrocolloid Dressings

This is the first in a series of articles which will examine the use of various types of wound dressings in clinical practice. The properties of the specific wound dressing, the types of wound the dressing is most suitable for, and the correct application and removal of the dressing will be discussed in each article. The hydrocolloid dressings to be examined are Granuflex, DuoDerm Extra Thin, Comfeel, Tegasorb Advanced Formulation and Combiderm, which all come in a variety of shapes and sizes.

Nipple wound care: a new approach to an old problem.

Nipple soreness and nipple trauma have long been associated with breastfeeding, and persist despite the many clinical advancements in the field of lactation. Management of nipple wounds has been approached in a variety of ways over the years in an attempt to treat and resolve this problem. Incorporating the scientific principles of modern wound care management can provide additional effective treatment options. Wounds are characterized by depth and extent of tissue destruction, regardless of their location on the body. Current wound treatment methods employ the use of moisture to aid healing. A moist environment is critical for epithelization, the proliferation and migration of epithelial cells across the surface of a wound during healing. Nipple wounds also heal by this process. Using a particular type of wound dressing, a hydrogel sheet wound covering, on a nipple wound offers several advantages. These dressings help maintain a moist environment, decrease the chance of bacterial infection, are easy to use, and provide immediate pain relief.

Interactive wound dressings. A practical guide to their use in older patients.

The properties of an ideal wound dressing do not change with the introduction of new types of wound dressing, but the range of effects on wound healing increases. The number of dressings available is enormous, and the choice between them is often bewildering. Because there is still no ideal dressing for all wound types, it is necessary to get to know a few well, and to avoid switching to new therapies solely on the basis of anecdotal reports. The adoption of novel dressings should be based on scientific evidence. At present, dressings are still chosen on the basis of local traditions and personal empirical experience, together with evidence from the few double-blind, placebo-controlled trials that have been performed. In the management of ulcers, a particular wound management plan should not be changed if the ulcer being treated is decreasing in size and the patient is comfortable. The dressing should be chosen with care. The type of chronic ulcer and its appearance, the amount of exudate and the presence or absence of pain all assist in the selection of an appropriate wound dressing product. Quality-of-life aspects are important. In the elderly, good quality of life may not necessarily require complete ulcer healing, although this is naturally desirable. Dressing changes should be minimised and the ulcer should be kept moist and the surrounding skin dry. The high cost of interactive dressings is a potential disadvantage of their use. However, if the wound can be re-dressed at longer intervals and if healing occurs more quickly, their use may be cost effective and associated with less pain and a better quality of life.

A Novel Wound Dressing With an Antibiotic Delivery System Stimulated by Microbial Infection

The aim of this study was to develop a new wound dressing with controlled release of antibiotics only in the presence of inflection. In the first experiment using an infected dorsal pouch of rats, exudate containing proteinases from pouches contaminated with Staphylococcus aureus or Pseudomonas aeruginosa showed significantly higher hydrolytic activity toward Boc-Val-Pro-Arg-MCA than that from noninfected wounds. The authors then developed a new type of wound dressing (AGX), a drug delivery system in which gentamicin is bound to polyvinylalcohol hydrogel through an enzymatically degradable peptide linker containing a -(D)-Phe-Pro-Arg- sequence. To investigate in vitro effectiveness, AGX was incubated with exudate from S. aureus infected or P. aeruginosa infected wounds. Gentamicin was selectively released from AGX in the presence of the exudate from S. aureus infected or P. aeruginosa infected wounds, but was not released in the presence of exudate from noninfected wounds. Next, AGX or the polyvinylalcohol hydrogei that served as control was incubated with S. aureus in the presence of human plasma. After 24 hours, S. aureus concentration was markedly lower in the case with AGX than in that with polyvinylalcohol hydrogei. These results indicate that proteinases from wounds infected with S. aureus or P. aeruginosa cleaved the linker and gentamicin was released. ASAIO Journal 1997; 43:M854-M857.

A novel wound dressing with antibiotic delivery system stimulated by microbial infection

The aim of this study was to develop a new wound dressing with controlled release of antibiotics only in the presence of infection. In the first experiment using an infected dorsal pouch of rats, exudate containing proteinases from pouches contaminated with Staphylococcus aureus or Pseudomonas aeruginosa showed significantly higher hydrolytic activity toward Boc-Val-Pro-Arg-MCA than that from noninfected wounds. The authors then developed a new type of wound dressing (AGX), a drug delivery system in which gentamicin is bound to polyvinylalcohol hydrogel through an enzymatically degradable peptide linker containing a -(D)-Phe-Pro-Arg-sequence. To investigate in vitro effectiveness, AGX was incubated with exudate from S. aureus infected or P. aeruginosa infected wounds. Gentamicin was selectively released from AGX in the presence of the exudate from S. aureus infected or P. aeruginosa infected wounds, but was not released in the presence of exudate from noninfected wounds. Next, AGX or the polyvinylalcohol hydrogel that served as control was incubated with S. aureus in the presence of human plasma. After 24 hours, S. aureus concentration was markedly lower in the case with AGX than in that with polyvinylalcohol hydrogel. These results indicate that proteinases from wounds infected with S. aureus or P. aeruginosa cleaved the linker and gentamicin was released.