Special to OWM: CAWC Abstracts
The 7th Annual Conference of the Canadian Association of Wound Care met in London, Ontario, November 1 through 3.
The focus of the conference was "The Many Faces of Wound Caring: Interdisciplinary Teams Providing Patient-Centered Care." Ostomy/Wound Management is fortunate to have received a number of rigorously reviewed abstracts presented at CAWC that illustrate the breadth and depth of research relevant to wound care. These abstracts were selected for publication by an interdisciplinary abstract review committee comprising a total of seven of the authors' peers. An equal number of abstracts were selected from oral and poster presentations. In publishing these abstracts, the editors hope to increase attention to the issues they address, expedite necessary changes to care protocols, and stimulate further research efforts among clinicians who may take the value of their day-to-day accumulation of knowledge for granted.
A Potential Use of Liposome Associated Interferon-alpha-2b for Treatment of Post-Burn Hypertrophic Scar
A. Ghahary, E.E. Tredget, and M. Takeuchi, Wound Healing Research Center, University of Alberta, Edmonton, Alberta, Canada
As previously reported, interferon-alpha-2b (IFN-a2b) can be encapsulated in liposomes without compromising its antifibrogenic effects on dermal fibroblasts in vitro. This study was conducted to determine whether this preparation, applied topically to dorsal guinea pig wounds, can improve the fibrotic conditions. The rationale for this approach is that the systemic administration of IFN-a2b by subcutaneous injection for treatment of dermal fibrosis is uncomfortable, requiring large quantities of the cytokine, and cannot be easily used in children. Liposomes are a potentially useful vehicle for the topical delivery of drugs. Empty sonicated liposome vesicles were mixed with various concentrations of IFN-a2b and then dried and rehydrated. An enzyme-linked immunosorbent assay (ELISA) was used to determine the efficiency of encapsulation and the stability of the preparation under experimental conditions. A total of 36 full-thickness skin wounds (six/animal, three on each side) were made with an 8-mm disposable punch. Each wound on the right side was treated with liposome cream (100 mg/wound) containing 3,000 units of liposome-encapsulated IFN-a2b. Wounds on the left side were treated with empty liposomes. A significant reduction in rate of wound contraction occurred. This reduction remained significant up to 10 days. Northern analysis, used to evaluate the expression of mRNAs for type I and type III collagens in response to IFN-a2b, showed a marked reduction in the abundance of the transcripts for the pro-a 1(I) chain of type 1 collagen on days 11 and 14 after wounding. Similarly, the level of mRNA for type III procollagen was markedly reduced as early as day 7 and remained depressed up to day 14. These findings were consistent with results obtained for the total collagen content in tissue samples. Cellularity of the IFN-a2b-treated wounds, assessed by vimentin content, was also markedly reduced at day 7 and remained depressed up to day 14. Liposome associated IFN- a2b applied 5 days after completion of epithelialization reduced the mRNA for the pro-a 1(I) chain of type 1 collagen, confirming its transepidermal penetration and effectiveness. The activity of liposome-associated IFN-a2b in vivo supports the concept of the topical use of this antifibrogenic agent for treatment of fibroproliferative disorders.
This study has been supported by the Toronto Hospital for Sick Children Foundation.
The Leg Ulcer Measurement Tool: Can It Detect Change in Wound Appearance?
M.G. Woodbury, Parkwood Hospital, St. Joseph's Health Care, London, Ontario; P.E. Houghton, School of Physical Therapy, University Western Ontario, London, Ontario, Canada; K.E. Campbell, Parkwood Hospital; and D. Keast, Parkwood Hospital
Epidemiological studies performed in the United States and other countries suggest that chronic leg ulcers occur in approximately 1% of the population, with venous insufficiency being the most common underlying cause (70% to 90%). Leg ulcers are the cause of considerable human suffering and cost to the healthcare system. Various therapies that have been purported to accelerate closure of chronic wounds have been developed over the last 30 to 40 years. However, to assess the effectiveness of these adjunctive wound therapies, a measurement tool that not only will describe the current condition of the leg ulcer but also detect any improvement or deterioration in wound status over time is necessary. In response to this need for an appropriate leg ulcer assessment tool, the Leg Ulcer Measurement Tool was developed. Its content validity, intrarater, and interrater reliability have been established previously. The ability of the LUMT to detect improvement or deterioration in wound status over time, as well as its responsiveness, were assessed. The leg ulcers of 22 subjects have been evaluated monthly for 4 months. In addition, measuring wound appearance using the Leg Ulcer Measurement Tool, acetate tracings of the surface area of the wound were made. The tracings were used to classify the wounds as improving toward closure or deteriorating. The responsiveness of the Leg Ulcer Measurement Tool is reported in terms of several responsiveness indices or measures used in the literature. The clinical and research implications of the findings are discussed.
The Prevalence of Wheelchair and Seating Intervention Needs in Long-Term Care in London, Ontario
K. Goodman, St. Joseph's Health Care, Parkwood Hospital, London, Ontario, Canada; K.A. Forward, University of Western Ontario, London, Ontario, Canada; F. Miller, St. Joseph's Health Care; and K. Trenholm, St. Joseph's Health Care
The purpose of this study was to determine the prevalence of and need for wheelchair and seating intervention for wheelchair users in the long-term care population of London, Ontario. A population-based study included 169 subjects who live in one of 10 long-term care facilities who were assessed using the Seating Identification Tool. The Seating Identification Tool is a screening tool developed to assist healthcare professionals in identifying individuals using wheelchairs who would benefit from formal wheelchair and seating intervention. The results of this study indicate a need for seating intervention. The study revealed that 62.7% of the subjects obtained a score on the Seating Identification Tool that indicated a need for a seating assessment. The greatest concern identified by the subjects was reports or demonstration of discomfort in their current seating device. Of all the participants, 41.4% reported "red areas on their bottom" and 36.1% were repositioning due to sliding and leaning. Prevalence estimates, such as those from this study, can be useful to policymakers because they draw attention to under-serviced populations. Based on the results of this study, elderly individuals in long-term care facilities need wheelchair seating and intervention.
Promoting Best Practice: A Pilot Project for Pressure Ulcer Prevention and Management
F. MacLeod, West Park Health Care Centre, Toronto, Ontario, Canada
Three units (n = 76 beds) showed the highest prevalence of pressure ulcers in a large complex continuing care center. Associated health problems such as multiple sclerosis, arthritis, dementia, and brain injuries contributed to the wound healing challenge. Although the center was equipped with recommended support surfaces and equipment for pressure reduction, competent use of products and current practice standards were lacking. A pilot project was designed to provide education and resources to the clinical teams. Two protocols were developed based on existing practice guidelines and reviewed by the interdisciplinary skin and wound care team and a geriatrician. First, a protocol on prevention of pressure ulcers was introduced to the units' teams through a series of sponsored pizza lunches. Excellent attendance by both professionals and unregulated workers was gratifying, especially because the latter group is responsible for identifying and communicating potential ulcer problems to the team. The second phase of the project included education of seven registered nurses identified as unit resources. They attended a 1-day workshop on protocol for wound management and accessed supports such as journal articles, individual coaching from the Advanced Practice Nurse for Wound Care, and bimonthly seminars. Six months later, the resource RNs demonstrated increased independence with pressure ulcer assessment and management. In addition, written plans of care and summaries reflected current practice as outlined by the new protocols. The project's impact on pressure ulcer prevalence has been compounded by the admission of several patients with severe ulcers.
Occlusive and Semi-Occlusive Dressings: Reality versus Myth
K. Laforet, 3M Canada, London, Ontario, Canada, and G. Berardinucci, 3M Canada, Montreal, Quebec, Canada
Since the advent of moisture-retentive wound dressings in the 1970s, the terms occlusive, semi-occlusive, semi-permeable, oxygen permeable, or oxygen impermeable dressings have been used interchangeably. The result is inconsistent use of the terms and confusion regarding occlusive versus semi-occlusive dressings in chronic wound care management. This study intended 1) to identify how occlusive versus semi-occlusive wound dressings are defined in the literature, and 2) to determine the clinical evidence to support the use of occlusive dressings versus semi-occlusive dressings in chronic wound care. An English language literature MEDLINE search, using the terms wound dressings, occlusive, semi-occlusive, semi-permeable, oxygen permeable, and oxygen impermeable was completed. Manufacturers' literature was reviewed to determine how dressings were categorized. Randomized, controlled clinical trials for chronic wound care and experimental trials that objectively measured wound-dressing performance were emphasized. The study reviewed 26 English language articles in the literature specific to chronic wound care that utilized more than one term for dressings as identified above. Of the 26 articles, 10 (38%) clearly defined the terms used, 16 (62%) used terms without defining them, and 16 (62%) used the terms interchangeably. No studies showed a statistically significant difference in clinical outcomes with occlusive versus semi-occlusive dressings. The authors concluded that the terms occlusive and semi-occlusive are not consistently used in the chronic wound care literature. No clinical evidence supports the use of occlusive versus semi-occlusive dressings in the treatment of chronic wound care. A consensus on the definitions of chronic wound care dressings is needed.
The Impact of Nanocrystalline Silver Dressings on the Activity of Matrix Metalloproteinases in Chronic Wounds
H.L. Orsted, Calgary Regional Health Authority, Calgary, Alberta, Canada; J.B. Wright, Westaim Biomedical Corporation, Fort Saskatchewan, Alberta, Canada; K. Lam, Westaim Biomedical Corporation; and R.E. Burrell, Westaim Biomedical Corporation
Excessive activity of matrix metalloproteinases has been associated with impaired healing of wounds. This association is particularly well established in venous stasis ulcers. Therefore, research efforts have been directed toward finding different mechanisms of inhibiting matrix metalloproteinases activity and determining the effect of such inhibition on wound healing. Porcine model studies have suggested that nanocrystalline silver dressings modulate the activity of matrix metalloproteinases in vivo. A pilot prospective clinical study was conducted to evaluate the impact of these dressings on individuals with chronic ulcers of various etiologies. The study evaluated the level of matrix metalloproteinases activity of wound fluids recovered from patient dressings before and after dressing with nanocrystalline silver. The recovered wound fluid was examined by enzyme zymography in combination with fluorogenic matrix metalloproteinases activity assays. The results indicated that within 2 days following the switch to the test dressings, the activity level of matrix metalloproteinases dropped substantially, although not uniformly, in all patients. The decrease in matrix metalloproteinases activity in wound fluid was associated with an improvement in the appearance of the ulcers. The authors concluded that nanocrystalline silver is able to modulate matrix metalloproteinases activity rapidly in wounds without eliminating the matrix metalloproteinases activity required for wound healing.
Product notation: Acticoat(TM) Antimicrobial Barrier Dressing, Westaim Biomedical Corporation, Fort Saskatchewan, Alberta, Canada.
A Wound Model Utilizing Artificial Wound Fluid to Compare Wear Time of Hydrocolloid Dressings
L.K. Sproule, 3M Canada Company Inc. London, Ontario, Canada; N.P. Atwood, 3M Health Care, St. Paul, Minn.; C.T. Lyle, 3M Health Care, St. Paul, Minn.; S.E. Solfest, 3M Health Care, St. Paul, Minn.; and J.B. Lutz, 3M Health Care, St. Paul, Minn.
Applying hydrocolloid dressings to moist skin is a challenge for healthcare professionals. Moisture can be endogenous (eg, exudate) or exogenous in nature (eg, sweat, incontinence). A model using healthy volunteers for comparing wear time of hydrocolloid dressings under moist skin conditions has been developed that simulates common environments seen in everyday clinical practice. The objective of this study was to use this procedure to compare wear times of two commercially available hydrocolloid dressings. The two dressings were randomly applied over wound models on both volar forearms of 18 subjects. The simulated wound consisted of a nonstick absorbent pad cut to approximate a 2.5-cm x 2.5-cm wound with a 0.7-mm microcannula inserted into the pad. The absorbent pad served as a fluid reservoir into which artificial wound fluid was infused. Saline is often used to compare absorptive capacities of dressings; however, saline is chemically very different from wound fluid and various absorptive wound care products react differently to saline. This model uses a formulation of artificial wound fluid based on reported components of human extracellular fluid and of chronic wound fluid. In this study, artificial wound fluid was infused at a rate of 7.2 mL/day for a maximum of 5 days in order to mimic a moderately exudating chronic wound. Additionally, subjects entered an environmental chamber for 30 minutes/day maintained at 98 degrees F and 94% relative humidity to induce sweating. To simulate incontinence in the chamber, subjects soaked the dressings with wet paper towels. Dressings were checked daily for lift and leakage. Results indicate significant differences (P < 0.05) in time to failure between the two dressings.
Implementation of a Comprehensive Wound Care Program in a Tertiary Care Hospital
L.M. Teague, J. Li, and J.L. Mahoney, St. Michael's Hospital, Toronto, Ontario, Canada
Reducing hospital-acquired (incidence) pressure ulcers requires vigilant risk assessment. The application of evidence-based interventions can prevent these devastating wounds. Pressure ulcer prevention requires assessment and intervention from the entire healthcare team, from clinical assistants to attending physicians. Since 1998, a tertiary care hospital in Toronto has implemented a pressure ulcer prevention and treatment program, utilizing the Braden Scale, National Pressure Ulcer Advisory Panel pressure ulcer staging system, the AHCPR guidelines, and most recently the Canadian Association of Wound Care best practice guidelines for the prevention and treatment of pressure ulcers.
Through the education of healthcare providers, the primary goal is reduce the incidence of pressure ulcers by 50%. The Kinexus (KCI Medical, Inc.) program has been utilized to monitor pressure ulcer prevalence and incidence outcomes since 1997. Statistically significant reductions in both prevalence and incidence of pressure ulcers have been achieved with the implementation of the Wound Healing and Skin Ulcer Prevention Program. The results of this evolving hospitalwide program are presented.
The Use of Nanocrystalline Silver under a Three-Layer Compression Bandaging System to Treat Chronic Venous Stasis Ulcers in a Diabetic Patient
L.J. D'Souza, Royal Victoria Hospital Pavilion, McGill University Health Center, Montreal, Quebec, Canada
Chronic venous stasis ulcers impact the patient (especially the elderly person with diabetes) quality of life and can present a challenge to the wound healing professional. The effort to attain and maintain a low or nonexistent bioburden while providing tolerable maximum compression may limit patient mobility and comfort and alter quality of life. This may lead to a cycle of noncompliance and delayed wound healing. State-of-the-art technology and ingenuity can help overcome the challenge.
An 80-year-old female who had type II diabetes for 40 years presented with an 11-month chronic malodorous venous stasis ulcer proximal to the left external malleolus (ankle brachial pressure index = 0.83). One month earlier, the wound cultured 3+ for Pseudomonas. Dressing the wound with silver sulfadiazine covered with a foam dressing and a four-layer compression bandage had been attempted on numerous occasions but the patient removed it, complaining of continuous irritation and restriction. The periwound appeared red, raw, and irritated. A multiphase plan was initiated. Applying a topical corticosteroid to the periwound along with a hydrofiber helped control the irritation; however, a large amount of exudate, edema, colonization, and size of the wound remained constant. The wound was cleansed with saline and a semiquantitative swab was taken. A nanocrystaline silver dressing under a three-layer compression bandage was applied and the patient was seen the next day. A dramatic reduction in size, odor, and exudate was noted. Although the patient complained of some discomfort, she was encouraged by the progress and agreed to continue the same treatment. The patient was seen every 3 days for the first few weeks and subsequently once per week. Complete closure was achieved by the end of the twelfth week. The patient was then measured and fitted for 30 mm Hg compression stockings. Application devices were supplied along with teaching and a promise of support and weekly phone calls from the clinic nurses. Attention to patient needs and ingenious use of state-of-the-art technology may help wound care providers meet the challenge of wound healing.
Development of Best Practice Guidelines for Nurses in Ontario: Pressure Ulcer Prevention
F. MacLeod, West Park Healthcare Centre, Toronto, Ontario, Canada, and T. Virani, Registered Nurses Association of Ontario, Canada
Older adults who experience an illness or surgery are particularly at risk of developing pressure ulcers. The need for staff to have current knowledge about pressure ulcer prevention is paramount. Unfortunately, nurses do not always have access to expertise and resources to guide their practice. However, in 1999 the Registered Nurses Association of Ontario, with funding from the Ministry of Health and Long-Term Care, embarked on a 3-year project to develop, test, disseminate, and evaluate 17 best practice guidelines for nurses. For the pressure ulcer prevention component, a panel of nurse experts reviewed and rated five selected guidelines using a modified version of the "Appraisal Instrument for Canadian Clinical Practice Guidelines" (Cluzeau et al, 1999; modified by I. Graham and M. Harrison, 2000). This consensus approach resulted in the development of a best practice guideline, Risk Assessment and Prevention of Pressure Ulcers in the Older Adult Population. Further processes included stakeholder feedback, formal selection of a consortium of implementation sites, and hiring an advanced practice nurse to develop education components and implement the guidelines over 6 months. In addition, a team of academic researchers evaluated outcome indicators. By Fall 2001, the guidelines will be edited and dissemination across Ontario will begin. The authors describe the various processes used and associated challenges and successes.
Selection Guide for Support Surfaces: A Pilot Study
S. Draper, Ottawa Hospital General Campus, Ottawa, Ontario, Canada
An important component of any skin care program is the appropriate use of support surfaces for pressure reduction/relief. Healthcare professionals are faced with a large number of support surfaces from which to choose and numerous patient factors and support surface characteristics to consider during the selection process. The selection is even more difficult because of the lack of universal criteria for product selection. The authors describe the experience of a Canadian tertiary care teaching hospital that developed, piloted, and evaluated a clinical intervention to guide the selection of support surfaces. The Selection Guide for Support Surfaces was pilot-tested for 6 weeks on two medical and two surgical units. Sixty-eight percent of the staff found this guide for easy to very easy to use and 82% found the tool helpful for selecting support surfaces. Ninety-six percent of staff nurses favored hospitalwide implementation of a revised guide. Facilitating factors and barriers having implications for hospitalwide implementation are discussed in this presentation. Suggested revisions to the guide and implications for practice and further study also are discussed. Institutions need to develop guidelines for choosing support surfaces and evaluate their appropriateness for clinician use and for use with various patient populations.
Understanding the Home Care Expenditures for Individuals with Leg Ulcers
E. Friedberg, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; M. Harrison, Queens University, Kingston, Ontario, Canada; and Ian Graham, Ottawa Hospital Research Institute
Nursing and supply expenses related to the care of chronic wounds in the home environment in a large urban center of Ontario have raised concern. As one aspect of a larger regional prevalence study of leg ulcers, home care expenditures were examined over a 1-month period for this segment chronic wound population. Individuals with an ulcer below the knee (including the foot) receiving nursing services in the home were eligible for inclusion and invited to participate. Specially trained nurses visited all clients and completed an in-depth assessment of their social, medical, and leg ulcer history. Legs were inspected, an ankle brachial pressure index was determined, and ulcers were examined and measured. Supply usage over a 1-month period was tracked and the travel and treatment time as well as the mileage for each nursing visit were recorded during this time period. Over the 1-month period, 2,270 visits were made (mean treatment time = 26 minutes, mean travel time = 17 minutes). The home care authority reimbursed the nursing agencies $34.36 per visit ($80,618 for the month) and spent $21,058 in supplies for the care of people with leg ulcers. In the region, the annual visit expenditures by home care for nursing visits and supplies were estimated to be $1.5 million. Efficiencies could be gained in several ways: reduction of the 40% visit time attributed to travel; reduction of frequency of visits for patients with little or no drainage; attention to "best practice"; and the use of known effective interventions such as compression bandaging for patients with ulcers of venous etiology.
Effects of Ultraviolet Light C on the Bacterial Burden in Chronic Ulcers
T.P. Thai, School of Physical Therapy, Elborn College, University of Western Ontario, London, Ontario, Canada; P.E. Houghton, School of Physical Therapy, Elborn College; D.H. Keast, St. Joseph's Health Care, Parkwood Hospital, London, Ontario, Canada; M.G. Woodbury, School of Physical Therapy, Elborn College and St. Joseph's Health Care; and K.E. Campbell, St. Joseph's Health Care
The purpose of this study was to evaluate the ability of ultraviolet light C to reduce the amount and type of bacteria present in chronically infected ulcers. Chronic ulcers with clinical signs of infection present in 22 individuals received a single treatment using an ultraviolet light C lamp (wavelength = 254 nm) placed 1 inch from the wound bed for a period of 180 seconds. Semiquantitative swabs taken immediately before and after ultraviolet light C treatment were used to assess changes in the bacterial bioburden present within the wound bed. The mean score of semiquantitative swabs decreased significantly from 3.36 before ultraviolet light C treatment to 2.24 after ultraviolet light C exposure (P < 0.05). The bacteria Pseudomonas aeruginosa and Staphylococcus aureus appeared to be most affected by ultraviolet light C. A greater reduction in bacterial burden was observed following ultraviolet light C treatment in ulcers that had only one species of bacteria. In 12 ulcers in which methicillin-resistant S. aureus was localized, more than one ultraviolet light C treatment session was required to produce a significant reduction in the amount of the bacteria present in the wound bed. These results confirm previous laboratory studies and demonstrate directly that ultraviolet light C can kill bacteria such as P. aeruginosa, S. aureus, and methicillin-resistant S. aureus present in chronic wounds.