Symposium Update: The 21st Annual Symposium on Advanced Wound Care and the Wound Healing Society Meeting April 24 – 27, 2008 San Diego Convention Center

The development of an infected acute wound porcine model

  D Boone, MD; E Braitman, MD; J Afthinos, MD; C Gendics, RN; E Sordillo, MD, PhD; G Todd, MD; J Lantis, MD
  Introduction: To assess the many potential antimicrobial agents available as well as pro-growth agents, we found it necessary to develop a medium-sized animal model. While there are many animal models for infection, many of them include a wound inhibiting therapy, as an adjunct. In addition, in most models there is not a delay between inoculation and treatment. Therefore, making the models suboptimal to assess the treatment on critical colonization.   Methods: A total of 12 animals (50-kg pigs) had four 6-cm in diameter full-thickness wounds created. The reservoir of the wound was filled with a mixture of Pseudomonas aeruginosa, Staphylococcus aureus, and Bacteroides fragilis in a ratio of 2:2:1 at a concentration of 107 CFU/cc. A standard gauze was then placed in the wound and covered with a bio-occlusive dressing. Quantitative biopsies and semi-quantitative swabs were obtained at 72 hours, in addition histologic biopsies and digital images were obtained at this point in time. At that point therapeutic device assays were initiated.
  Results: One animal suffered a postoperative fatality of unknown etiology. One animal was euthanized secondary to an unrecognized medical comorbidity. Of the 40 remaining wounds, all were clinically infected. Two of the animals (eight wounds) required systemic antibiotic prior to their first biopsy because the wounds exhibited signs of local infection and the animals exhibited fever and tachycardia. All wounds showed significant bacterial counts and histological markers of infection. The two animals (eight wounds) that received antibiotics had significantly lower bacterial wound counts.
  Conclusions: We were able to create an effective model for invasive bacteria infection without systematically impairing the host. However, the classic teaching that systemic antibiotics do not effect the local wound bacterial burden may not be true, based upon the local wound environment findings from the two animals treated with systemic antibiotics.

Bacterial burden and wound outcomes as influenced by negative pressure wound therapy

  D Boone, MD; E Braitman, MD; J Afthinos, MD; C Gendics, RN; E Sordillo, MD, PhD; G Todd, MD, J Lantis, MD
  Introduction: While we continue to be aware that negative pressure wound therapy (NPWT) provides significant clinical benefits, we remain somewhat ignorant as to the mechanism through which it works. Some investigators have postulated that mechanical removal of bacteria may play a role. To facilitate this process, a theoretically bacteriocidal (silver) sponge has been added to the NPWT technology. In order to understand the effect of NPWT on bacterial burden and wound response we treated a porcine infected wound model with NPWT and NPWT with silver dressing.
  Methods: Sixteen chronically infected (Pseudomonas, Staphylococcus aureus, Bacteroides fragilis) wounds in a porcine model (described in separate submission) were treated with NPWT standard foam or silver foam for a period of 7 days with three dressing changes. At each dressing change quantitative, semi-quantitative bacterial cultures, histological samples, and digital photographs were taken.
  Results: The wounds continued to show gross and microscopic improvement when treated with NPWT and NPWT with silver in comparison moist wound care controls. However, the bacterial burden continued to increase and broaden to include local skin flora that had been absent immediately after wounding. These increases in bacteria were not affected by the use of silver dressings.
  Conclusion: The application of NPWT and NPWT with silver to an infected wound model shows there are significant improvements in local wound appearance and histologic and gross markers of healing. This occurs despite the NPWT and NPWT with silver having no effect on the bacterial burden in the wound. Therefore, the control of bacterial burden in the chronic wound is unlikely to play a role in the salutatory effects of NPWT that are seen in wound healing.

Long-term mortality in diabetics after nontraumatic amputation

  Melissa E. Brawner, DPM, MS; Cory Baxter, DPM; Lawrence A. Lavery, DPM, MPH
  Background: It is well documented in the literature that lower extremity amputations increase mortality. However, little has been reported about long-term mortality associated with nontraumatic amputations secondary to ulceration in the diabetic population. Additionally, few studies have investigated the comorbidities that may contribute to mortality after diabetic amputation.
  Purpose: The purpose of this study is to determine the long-term mortality associated with nontraumatic diabetic amputations and investigate the effects of associated comorbidities.
  Methods: Information from medical records was abstracted and summarized for each hospitalization for nontraumatic diabetic lower extremity amputation from January 1 to December 31, 1993, in six metropolitan statistical areas in south Texas. Social Security Death Index was used to identify mortality data for the same group in 2007. Subject social security number, name, and date of birth were used to identify date of death. Variables recorded included age, height, weight, sex, hospital admissions, ulcerations, amputation status, the presence of vascular disease, cardiac disease, renal disease (CRI defined as having GFR <60), and surgical and social history.
  Results: 1,043 charts were reviewed that matched the criteria. Overall mortality at 3, 5, and 10 years was 38.5%, 52.3%, and 75.9%, respectively. Patients on dialysis had a consistently higher mortality rate than those with CRI or without renal disease despite associated comorbidities. Additionally, dialysis patients were at a significantly higher risk for undergoing a higher level amputation. Logistic regression analysis showed the significant risk factors for mortality to be amputation level, dialysis, and age.
  Conclusion: The results of this study support the need for adequate wound care in order to prevent amputation and therefore decrease mortality. Additionally, it appears there is a significant need for wound care and amputation prevention in diabetic patients on hemodialysis.

The role of high-voltage, pulsed electrical stimulation in limb salvage for diabetic patients

  Jeremy J. Burdge, MD; Jodi F. Hartman, MS; Michelle L. Wright, BS
  Increasing evidence supports the use of high-voltage, pulsed electrical (HVPE) stimulation for the treatment of chronic, full-thickness diabetic wounds of the lower extremity.
  This retrospective study evaluated the efficacy of HVPE stimulation as an adjunctive therapy in the treatment of the first consecutive 45 diabetic wounds (30 patients) that failed to improve despite multidisciplinary wound treatment, including vascular evaluation and surgical intervention as indicated, aggressive offloading, bacterial infection control, and wound debridement.
  Mean wound age was 25.0 weeks (4.0-60). Mean wound surface area was 7.8 cm2 (0.6-62). Wound locations included the foot (48.9%), heel (26.7%), lower extremity (15.6%), and ankle (8.9%). University of Texas Diabetic Wound Classifications were 5 (11.1%) IA, 2 (4.4%) IB, 14 (31.1%) IC, 1 (2.2%) IIA, 7 (15.6%) IIC, 4 (8.9%) IID, 2 (4.4%) IIIB, 3 (6.7%) IIIC, and 7 (15.6%) IIID. Comorbidities included neuropathy (83.3%), peripheral vascular disease (76.7%), cardiac disease (36.7%), infection (33.3%), osteomyelitis (16.7%), and morbid obesity (10%).
  Mean number of electrical stimulation treatments was 22.3 (6.0-40). Thirty-five (77.8%) wounds healed at a mean time of 14.2 weeks (3.4-59). At a mean follow-up of 39.8 weeks (11.1-84.3), 31 (68.9%) wounds remained healed. For the four (8.9%) recurrences, additional electrical stimulation subsequently healed two wounds, below knee amputation was required in another, while treatment is pending for the remaining wound. Ten (22.2%) wounds failed to heal, resulting in a transmetatarsal amputation for one patient (one wound) and below knee amputation for five patients (six wounds).
  These results suggest that HVPE stimulation is a useful adjunct to a multidisciplinary limb salvage approach for the management of complex lower extremity diabetic wounds for which conservative treatment has failed. Amputation, a major source of morbidity and occasionally mortality among diabetics, was avoided in the majority of patients.

Objectively testing edge stability of support surfaces

  Evan Call, MS; Laurie M. Rappl, PT, CWS; Nathan Call
  Support surfaces affect tissue by managing pressure, shearing, heat, and moisture. However, the support surface also must keep patients safe as they ingress, egress, and roll, to prevent entrapment and patient falls.
  This poster describes a pilot study using laboratory simulation to measure the stability of the edges of five different mattress technologies: viscoelastic foam, standard foam, air-filled, air-filled with air-filled bolsters, and air-filled with foam-filled bolsters. The two studies simulated sitting on the edge of a mattress, and rolling toward the edge of the mattress.
  In edge sitting, a wooden mold of buttocks and thighs were loaded with 125-lb and lowered onto the edge of the mattress. A force gauge at approximate knee height measured the force pushing the mold off the bed.
  In rolling, a mannequin simulating a 6' 0”; and 167-lb man was laid in the center of the mattress. Using an over-the-bed rig, we bent the mannequin’s knees and rolled it toward the edge of the bed to simulate the supine-to-sit motion. The point of edge-collapse was marked by two measures–the distance from the center of the mattress that the mannequin traveled and the amount of pressure the mannequin was exerting at the point of collapse.
  The five mattress technologies behaved very differently in both tests. The air-filled with foam-filled bolsters was significantly more stable in both edge sitting (first graph) and in rolling (second graph). In addition, four of the mattress configurations collapsed well before the edge was reached, indicating that the patient could not utilize the full width of the mattress safely. However, on the air-filled with foam-filled bolsters mattress, the full width was safe to use.
  These tests will help the clinician to choose mattresses that address the patient’s skin and the patient’s safety.

The importance of using medical grade honey rather than table honey in the treatment of wounds

  RA Cooper, L Jenkins, R Rowlands
  When antimicrobial agents are being evaluated prior to their introduction into conventional medical practice, advance publicity may interest potential patients but access to that agent will be restricted until licensed products are released and distributed. Cheaper, alternative remedies may not be available. Honey is an ancient remedy that has been re-introduced into modern wound care with the development of sterile devices utilizing medical grade honey (MGH). Media and public interest in this innovation may persuade patients, their relatives or even healthcare practitioners to use table honey from supermarkets as a cheap, readily available alternative to more expensive, regulated, honey-based wound care products. This study was designed to compare the antibacterial potency and microbial flora of 18 table honeys to a representative sample of manuka honey or MGH with a view to exploring their therapeutic potential. Antibacterial activity of each honey was compared to phenol using an agar well diffusion bioassay and Staphylococcus aureus. Bacteria and fungi were isolated and characterized as far as possible using standardized selective and enrichment methods. Using the bioassay antibacterial activity was detected in nine of the honey samples ranging from 4.2% to 18.6% (w/v) phenol equivalent and MGH was the most active. No micro-organisms were isolated from the sterilized manuka honey, but all other honey samples contained a variety of mesophilic aerobic bacteria and anaerobes. Although none of the isolates were overt pathogens, some have occasionally been isolated from debilitated patients and four samples yielded an indicator species of an unhealthy beehive. The recovery of such organisms illustrates the increased risks of infection associated with the clinical use of nonsterile honeys and their low antibacterial potency indicates their inferior antiseptic qualities.

The inhibition of biofilms of Pseudomonas aeruginosa with manuka honey

  RA Cooper, L Jenkins
  Biofilms have been linked to persistent infections, implicated in wounds, and postulated to contribute to chronicity. One pathogen that causes persistent infections in wounds is Pseudomonas aeruginosa; this opportunist pathogen is not only notoriously difficult to inhibit with antibiotics, but it also has the ability to form biofilms in which susceptibility to antimicrobial agents is further reduced. Antimicrobial interventions to prevent and/or treat biofilms are limited and effective topical agents are required. Planktonic cells of P aeruginosa have been shown to be sensitive to manuka honey and this study was designed to evaluate the potential of manuka honey in reducing Pseudomonas biofilms in the laboratory. A culture of P aeruginosa isolated from a chronic leg ulcer was cultivated at 37˚C in tryptone soya broth (TSB) for 24 hours in flat-bottomed sterile microtiter plates. Planktonic cells were removed aseptically using a sterile pipette and medium was replaced into wells with adherent bacteria using TSB containing 50% (w/v) manuka honey*. At varying intervals up to 24 hours, medium was removed, cells were immediately fixed with 2.5% glutaraldehyde, washed with PBS, stained with crystal violet and absorbance determined. Some wells received TSB without honey (positive control) and some wells were not inoculated (negative control). The experiment was performed on three separate occasions. A decrease in the extent of biofilm was seen in all wells exposed to 50% (w/v) manuka honey; whereas, biofilm in untreated wells increased. This study suggests that manuka honey is effective in disrupting biofilms in vitro. Its efficacy in vivo must now be tested.
  *Comvita Manucare 18+

Biochemical profiles of healing and nonhealing pressure ulcers

  LE Edsberg, KM Fries, MS Brogan, JT Wyffels
  Although the process of wound healing is well documented, the chronic wound presents a difficult problem. Wound healing is a complex process that follows a sequence of biochemical and cellular events. These events can be divided into four phases: coagulation, inflammation, proliferation, and remodeling. At each phase, specific cell types are present and particular biochemical reactions are occurring. Any interruption of the healing process will result in a chronic wound, and the disruption can occur anywhere along the highly complex process. Significant differences exist in the microenvironment of acute and chronic wounds. Studies done on wound fluids have revealed that certain growth factors, cytokines, and proteases are present during the wound healing process. Both in-vivo and in-vitro studies have detected differing levels of cytokines, growth factors, and proteases in normal (acute) versus chronic wounds.
  Wound fluid samples were collected from 50 pressure ulcers. Sampling included the interior and periphery of each wound at 15 time points within 42 days. Total protein was measured and the samples were analyzed using 2-D electrophoresis. Proteins present in gels were analyzed using Biorad Proteomeweaver software for each wound and interior and peripheral proteins were compared. Proteins of interest were extracted from the gel and identified using mass spectrometry. Multiplexed isobaric tagging technology (iTRAQ™) experiments were conducted to compare the proteins present at four time points in chronic and healing pressure ulcers. Wounds were photographed at each time point. Areas of the wounds were calculated and the resulting trajectories were plotted versus time. Tissue types were differentiated and their relative changes in area measured. This presentation will compare the biochemical profiles of healing and nonhealing wounds using 2-D electrophoresis and iTRAQ.

Diagnosing chronic wound infection: comparison of routine cultures, quantitative microbiology, and real time PCR

  Yelena Frankel, MD, MPH; Johan Melendez, MS; Lance Price, PhD; Jonathan Zenilman, MD; Gerald Lazarus, MD
  Background: Wounds account for >$15 billion in medical costs in the United States and diagnosing wound infection versus colonization in chronic wounds remains a major clinical challenge. Microbiology labs frequently report qualitative results (scant/moderate/heavy growth) without linkage to clinical outcome and often use a threshold of 105 organisms/g. Reliable quantification of bacterial loads and pathogen speciation are critical to correlating changes in microbial population with healing rates.
  Objectives: We evaluated biopsies from chronic wounds and compared quantitative and qualitative results. We determined microbiology by semiquantitative cultures in a clinical lab and quantitative cultures in a research lab. Species detection was compared between quantitative microbiology and real time polymerase chain reaction (RT-PCR).
  Methods: Seventeen patients presenting to an outpatient teaching hospital wound center with suspected chronic wound infection were enrolled. Tissue was obtained from the leading wound edge using a 3-mm curette.
  Results: By quant. microbiology 16/17 specimens were infected at >10⁵ cfu/g. Nine and seven of the bacterial organisms present were at 10⁷ cfu/g and 10⁸ cfu/g, respectively. In contrast, only 25% of the semi quant. cultures showed “heavy” growth. RT-PCR results were comparable to quantitative culture results. Most common pathogens included MRSA in 46% of the patients, Streptococcus group B in 22%, and Pseudomonas aeruginosa in 17%. Minimum tissue needed for reproducible measurements was 20 mg, easily obtained using a 3-mm curette and topical anesthesia with little loss of tissue or discomfort for the patient.
  Conclusion: Chronic wounds are highly complex ecosystems. Quantitative culture is more reproducible and reliable for determining bacterial load compared to routine semi-quantitative cultures. Modern molecular methods are promising for characterizing wound bacterial populations. PCR analysis provides results within 24 hours and can detect difficult-to-culture organisms, including bacteria residing in biofilms, anaerobes, and microaerophilic organisms, providing insight into inflammation and healing.

Management of diabetic foot ulcerations with acellular dermal regenerative tissue matrix and platelet-derived growth factor

  William P. Grant, DPM, FACFAS; Silvia E. Garcia-Lavin, DPM
  Diabetic foot ulceration remains a difficult challenge even with new and improved wound care products. The purpose study is to report on six diabetic plantar heel ulcerations treated with acellular dermal regenerative tissue rehydrated in platelet-derived growth factor and offloading the external fixation at the diabetic limb salvage center of the senior author. All six patients were type 2 diabetics >10 years. All presented with noninfected plantar heel wounds that were present for more than 4 weeks and all failed to heal with local wound care. All patients had thorough vascular, endocrinology, and internal medicine management and intervention if needed to maximize healing and medical clearance. All wounds were surgically treated at the fifth to sixth week. Sharp surgical debridement was used for wound bed preparation in all cases and grafted with acellular dermal tissue. In all six cases the acellular matrix is rehydrated in the platelet-derived growth factor, rich concentrated obtain from the patient’s own blood. All six cases used an Illizarov Hybrid external fixator for wound off loading with a footplate, which allowed for some protective weightbearing. Graft incorporation seen at 1-week post-op complete wound closure obtained at average 4.5 post-op external fixator frame removal at 6 weeks. Wound closure improved and graft take was enhanced with platelet-derived factor and complete offloading with external fixator frame.

”The Skin You’re In”: the development of an educational brochure for the public on the protection of the skin from the impact of environmental extremes

  Joe Ciccio, Teresa Conner-Kerr, Mary Haddow, Jamie Pinnock, Donna Scemons, Cindy Van Steelandt
  The Association for the Advancement of Wound Care (AAWC) Task Force for Public Awareness is a multidisciplinary panel commissioned to develop and implement a campaign to increase public knowledge of the science of wound healing and of the existence of the association as a resource to consumers.
  The goal is to publish a series of educational brochures, with The ABCs of Skin and Wound Care–A Guide for Treating Minor Wounds, published in 2005. After 2 years of research and with the Board of Directors’ approval, the committee is excited to present the next brochure.
  ”The Skin You’re In” was originally intended to focus on the impact of different seasons on skin integrity. Discussions highlighted the fact that the impact of “winter skin” is dependent on many factors, least of which is geography. The focus shifted to address the educational needs of the intended audience, the general public. Rather than “winter” and “summer,” the effects of cold, heat, humidity, and dryness on the skin are addressed in easy-to-read text, with colorful illustrations. Protection of the skin is the theme, with simple yet scientifically sound advice to help combat the effects of environmental extremes on the largest organ of the body. The brochure has essential information addressing physiology, risk factors, and prevention strategies.
  AAWC members will receive a copy of the brochure, which can be downloaded from www.aawcone.org by members and the public at no charge if used for educational purposes. It is anticipated that this information will build on the strong foundation to support ongoing education of the healthcare community and the public regarding AAWC, advances in wound healing, and skin protection and health.

Restructuring wound management practices: the Niagara Community Care Access Centre

  Theresa Hurd, Nancy Zuliani
  Wound care, although often unrecognized and unnoticed by many in the healthcare field, is a critically important issue that in most cases presents many fundamental opportunities for improvement. Increasingly, work is underway to better understand the negative impact of chronic wounds on patient health and well being, and the substantial burden wound care places on healthcare staff and organizations.
  Early efforts to improve wound care have focused primarily on the introduction of advanced products and technologies in the clinical setting. Although these efforts have been met with some success, they also have raised important questions about whether technological innovations have been adequately supported by clinical education and whether clinical outcomes can be sustained over time.
  The Niagara Community Care Access Centre (CCAC) in Southern Ontario has been involved in the implementation of a comprehensive approach to advanced wound management. Data collection and analysis over a period of more than 2 years have revealed findings related to implementation issues, clinical outcomes, patient health and quality of life, resource utilization, access to healthcare services in the community, program sustainability, and areas for further investigation. Data were collected at four points: in the fall of 2004, just prior to the introduction of the Advanced Practice Nurse, and then for three consecutive years in March 2005, 2006, and 2007. Findings revealed a decrease in clients requiring daily (or more frequent) dressing changes from 49% in 2004, to 14% in 2006, to 14% again in 2007. Ninety percent of venous leg ulcers are now compressed, and the average age of wounds within the population has decreased from 59 weeks in 2005, to 29 weeks in 2006, to 22 weeks in 2007.  Wound management services that are clinically effective and efficiently delivered are seen as an important prerequisite for enabling the Niagara CCAC to offer greater access to healthcare services in the community and to meet the growing demands for an increasingly broad range of healthcare services.

Pulsed radio frequency energy* therapy in elderly patients with Stage III and Stage IV pressure ulcers in long-term care settings

  Richard Isenberg, MD
  Rationale: Stage III and Stage IV pressure ulcers cause significant morbidity and often require advanced wound care modalities. This study evaluates the effectiveness of Pulsed Radio Frequency Energy* in the healing of Stage III and Stage IV pressure ulcers in elderly patients in long-term care settings.
  Methods: This is an open-label case series at 43 US long-term care facilities. Data collected included subject age, gender, wound type, location, and dimensions. Subjects received PRFE therapy as an adjunct to standard institutional wound care protocols.
  Results: One hundred, eighteen wounds were studied; 33 wounds were treated for 3 weeks and 85 were treated for 4 weeks. Most wounds were in residents of skilled nursing facilities (66%) and LTACHs (20%), with the remainder in spinal cord injury units, nursing homes or out-patient clinics. 30% (35/118) wounds were Stage III; 70% (83/118) wounds were Stage IV. Mean patient age was 69.9 years. Wounds were large, with mean initial wound area of 38.9 cm2, and chronic, with mean wound age of 10 months.
  Over the first month of PRFE therapy, the percentage of Stage III wounds that closed was 11.4% (4/35); 65.7% (23/35) reduced in surface area by >50%. Overall, Stage III Pressure Ulcers reduced an average of 67.9% in surface area, with a healing rate of 22.2 mm2/day.
  Among Stage IV wounds, 2.4% (2/83) closed and 28.9% (24/83) reduced in surface area by >50%. Overall, Stage IV pressure ulcers reduced an average of 32.7% in surface area in the first month, with a healing rate of 58.6 mm2/day.
  Conclusions: In the first 4 weeks, PRFE therapy leads to a significant reduction in wound size when treating chronic Stage III and Stage IV pressure ulcers in elderly patients.
  *PROVANT Wound Therapy System (Regenesis Biomedical, Inc., Scottsdale, Ariz)

Improving limb salvage in critical limb ischemia with intermittent pneumatic compression: a controlled study with 18- month follow up

  SJ Kavros, K Delis, NS Turner, AE Voll, DA Liedl, P Glovicski, TW Rooke
  Background: The purpose of this study was to evaluate the clinical role of IPC in the treatment of patients with chronic critical limb ischemia (CCLI), tissue loss, and nonhealing wounds of the foot on whom peripheral arterial revascularization had been exhausted.
  Methods: Performed in a multidisciplinary clinic, this study comprises two groups: group 1 consisted of 24 patients, median age 70 (IQR: 68.7-71.3) years, who received IPC for tissue loss and nonhealing wounds of the foot secondary to CCLI, in addition to wound care (IPC Group); group 2 consisted of 24 patients, median age 69 (IQR: 65.7-70.3) years, who received wound care for tissue loss and nonhealing wounds of the foot secondary to CCLI, without the benefit of IPC (Control Group). Outcome was considered favorable if complete healing and limb salvage occurred and adverse if the patient had to undergo a below knee amputation (BKA) subsequent to failure/deterioration of wound healing. Patients were followed up for 18 months.
  Results: In the Control Group, 20 patients (83%) failed to heal their foot wounds and underwent a BKA; the remaining four (17%, 95% CI: 0.59% to 32.7%) had complete healing and limb salvage. In the IPC Group 14 patients (58%, 95% CI: 37.1% to 79.6%) had complete foot wound healing and limb salvage. Ten patients (42%) in this group underwent BKA after failing healing of the foot wounds. Both wound healing and limb salvage were significantly better in the IPC group (P < 0.01). On study completion TcPO₂ on sitting was higher in the IPC Group than the Control Group (P = 0.0038).
  Conclusion: Our study data reveal that IPC implementation used as an adjunct to wound care in patients with chronic CLI and chronic nonhealing wounds/tissue loss improves the likelihood of wound healing and limb salvage when established treatment alternatives in current practice are lacking.

Expedited wound healing with noncontact, low-frequency ultrasound therapy in chronic wounds: a retrospective analysis

& nbsp; SJ Kavros, DA Liedl, AJ Boon, JL Miller, JA Hobbs, KL Andrews
  Background: To evaluate the clinical role of noncontact, low-frequency ultrasound therapy (MIST Therapy) in the treatment of chronic wounds of various etiologies. This study was designed as a retrospective observational study performed at a multidisciplinary, vascular wound healing center. Wound etiologies were categorized (ischemic, venous, neuropathic, and multifactorial) and their respective results evaluated in both the MIST Therapy and control groups.
  Methods: One hundred-sixty three patients who received MIST Therapy plus standard of care (Treatment group) and 47 patients who received the standard of care alone (Control group). MIST Therapy (n = 163) was administered to wounds three times per week with standard of care for 90 days or until healed. Control wounds (n = 47) received standard wound care with daily dressing changes. The proportion of wounds healed, the volume reduction, and the rate of healing were the main outcome measures of the study.
  Results: A significantly greater percentage of wounds treated with MIST Therapy and standard of care healed as compared with standard of care alone (53% versus 32%; P = 0.009). Additionally, one-way ANOVA revealed a significantly faster rate of healing with MIST Therapy based on increased slope of volume reduction compared with the standard of care alone (1.4 versus 0.22, P = 0.002).
  Conclusion: The rate of healing and complete closure of chronic wounds in patients improved significantly when MIST Therapy was combined with the standard of wound care. Further research on the healing impact of MIST Therapy in specific wound types will provide additional clinical insight into the use of this noncontact, low-frequency ultrasound therapy.

Treatment of ischemic wounds with noncontact, low-frequency ultrasound: the Mayo Clinic experience (2004-2006)

  SJ Kavros, JL Miller, SW Hanna
  Background: To evaluate the clinical role of a novel, noncontact, low-intensity, low-frequency ultrasound therapy (MIST Therapy) in the treatment of nonhealing leg and foot ulcers associated with chronic critical limb ischemia.
  Methods: This is a prospective, parallel-group, randomized, and controlled trial performed at a multidisciplinary vascular wound healing clinic. Thirty-five patients who received MIST therapy (MIST therapy group) as part of their standard of wound care and 35 patients who did not receive MIST therapy (Control group) as part of their standard of wound care were evaluated. Patient care consisted of standard of wound care alone or with the addition to MIST therapy for 12 weeks or until fully healed. MIST therapy was administered three times per week for 5 minutes per treatment. Outcomes were based upon the percentage of patients with greater than 50% reduction in wound size from the index measurement after 12 weeks of treatment. The relationship of transcutaneous oximetry pressure in the supine and dependent position as a factor in assessing the potential to heal ischemic ulcerations of the foot and leg also was examined.
  Results: A significantly higher proportion of patients treated with MIST therapy achieved >50% wound healing at 12 weeks than those treated with the standard of care alone (63% versus 29%; P <0.001). Thus, failure to achieve this minimum wound healing requirement occurred in 37% of MIST therapy group and 71% of control patients. The predictive value of baseline transcutaneous oxygen pressure may be of benefit to the clinician when assessing the potential to heal ischemic wounds.
  Conclusion: The rate of healing of cutaneous foot/leg ulcerations in patients with chronic critical limb ischemia improved significantly with MIST therapy as part of the standard of wound care.

Centralization of specialty beds and therapeutic surfaces links best practices with optimal outcomes at a tertiary care centre in Toronto, Canada

  Glenda Kerr, Karen Polansky, Laura Teague, Jianli Li
  Introduction/Background: Prior to 2005, specialty beds and therapeutic surfaces within an acute care tertiary centre were managed with a decentralized model. This led to cost and resource inefficiencies. In 2003, the SARS outbreak required the hospital to restrict and triage bed and therapeutic surface usage, thereby centralizing the equipment.
  Purpose: The purpose of this presentation is to describe the outcomes of shifting access to clinical equipment from a decentralized to a centralized approach. A new department was developed with objectives to decrease rentals, ease access to appropriate surfaces, and minimize pressure ulcer severity.
  Method: After recognizing the problem, a business case supporting a centralized approach was submitted to the senior management team. The Clinical Equipment Department was approved. Now, clinicians call one central number. The equipment is delivered, set up, and the patient is transferred onto the surface. The equipment is retrieved, cleaned, and serviced when no longer required.
  Results: Responses to referrals for equipment occur within 1 hour of request. Pressure ulcer prevalence has stabilized and continues in a downward trend from 22.3% in 2001 to 14.1% in 2006 (P = 0.005). With centralization, in the first full year of implementation, $170,000 in savings were realized.
  Conclusions: Equipment centralization infrastructure has improved utilization and efficiency of therapeutic surfaces across the hospital. Clinicians have timely access to the equipment, virtually eliminating renting. Centralization allows clinicians to access equipment to provide an optimal standard of care to patients identified as at risk for the development of pressure ulcers.

Generation of transgenic mice that inducibly express beta ig-h3 in the epidermis

  T Kwak, T Yufit, J Butmarc, SJ Kim, V Falanga
  Increasing evidence suggests persistent phenotypic alterations in fibroblasts from nonhealing human chronic wounds, which may result in faulty extracellular matrix deposition and keratinocyte migration. We have previously indicated that these cells are characterized by morphological changes, low proliferative potential, and unresponsiveness to TGF-beta 1. Recent work from our laboratory has shown a decreased expression of beta ig-h3 in chronic wounds and their fibroblasts compared to acute wounds. Beta ig-h3 is a transforming growth factor beta (TGF-beta) induced extracellular protein involved in a number of functions essential to cell adhesion, proliferation, and tumor invasion, but little is known of the specific role of beta ig-h3 in cutaneous wound healing. To establish a viable transgenic model for studying functions of beta ig-h3 in wound healing, we have generated transgenic mice, which allow focal induction of the beta ig-h3 transgene in the epidermis at different expression levels. Target transgenic mice that have a human beta ig-h3 gene fused with GAL4 binding sites upstream of the TATA promoter were generated. The transactivator mice were used that targeted the expression of GLp65 transactivators, fusion molecules containing a truncated progesterone receptor with a GAL4-DNA binding domain, with a human keratin 14 promoter. The target mice (TATA.beta ig-h3) and the transactivator mice (K14.GLp65) were mated to generate bigenic mice, and beta ig-h3 transgene expression was induced by topical application of RU 486 (mifepristone, a progesterone receptor antagonist). These inducible beta ig-h3 transgenic mice will be a novel method for better understanding of the role of beta ig-h3 in the pathogenesis of cutaneous wound healing.
  Acknowledgements: NIH sponsored Center of Biomedical Research Excellence (COBRE) P20RR018757 and NIDDK 067836.

Selecting skin care products for use in hyperbaric chambers may be dependent upon flammability acceptability indices score

  Darlene McCord, Barry Newton, Gwenael Chiffoleau, Jane Fore
  Background: Current protocols call for a cessation of adjunctive skin care treatments during hyperbaric care. The elevation of the oxygen fraction along with the increased pressure in the hyperbaric chamber dramatically increases the flammability potential of the materials in the hyperbaric atmosphere, leading to the need for rigorous standards to prevent the possibility of flame ignition. A scientific method of evaluating the flammability risks associated with the use of skin care products in the hyperbaric setting would be a clinically helpful tool.
  Methods and Materials: Independent studies were conducted comparing the oxygen compatibility for leading skin care products. Oxygen compatibility was determined using the autogenous ignition temperature (AIT) testing, oxygen index (OI) testing, and heat of combustion (HoC) testing. Products with a high AIT, a high OI, and a low HoC are recognized as being more compatible in oxygen-enriched environments. An Acceptability Index (AI) was calculated, using the above results for the tested products, to rank overall material compatibility in oxygen-enriched environments.
  Results: The AIT results did not exhibit a pattern as to the absence or presence of petroleum-based ingredients. The HoC testing revealed that products containing petroleum derivatives had a HoC that equaled or exceeded the HoC of gasoline; whereas, the products without petroleum-based ingredients exhibited significantly lower HoC. The OI of the nonpetrolatum containing skin products was significantly higher than products containing petroleum derivatives. The silicone-containing, petroleum-free products tested received up to a 25 times better AI than petrolatum-based products.
  Conclusions: There is wide variation in the safety profile of skin products. Skin products being considered for use in oxygen-enriched environments should be screened for flammability risks prior to use in hyperbaric settings. This will afford informed decisions about the fire safety of the products allowed. Further research is indicated.

Staphylococcus aureus virulence factors associated with infected skin lesions

  PM Mertz, TP Cardenas, RV Synder, MA Kinney, SC Davis, LR Plano
  Objective: Evaluate Staphylococcus aureus isolates from infected skin lesions for their potential to produce immune system modulating toxins and correlate these with white blood cell counts associated with these lesions.
  Design: Specimens were obtained for bacterial culture and Gram stain from 105 infected skin lesions and white blood cell counts per low power field (WBC/LPF) were determined. Chromosomal DNA was prepared from 85 bacterial isolates and subjected to real-time PCR analysis to determine the presence of genes encoding potential immuno-modulating toxins. Bacterial populations were divided into two groups; those associated with low, 0-5 WBC/LPF, or high, >5 WBC/LPF. Chi-square statistical analyses were applied to compare the toxin gene profiles associated with WBC counts on initial swab for culture.
  Results: A higher than expected percentage of bacteria capable of producing the exfoliative toxins (ETA and/or ETB) and Panton-Valentine leukocidin (PVL) was seen in all skin lesions infected with S aureus without regard to WBC count with initial cultures. Comparison of the toxins associated with low WBC group versus the high WBC group showed that low WBC counts were associated with ETA and ETB while high WBC counts were associated with PVL and toxic shock syndrome toxin (TSST). There were no differences in the clinical appearance of the lesions between groups.
  Conclusions: Staphylococcus aureus virulence factors ETA, ETB, and PVL are associated with WBC counts from infected skin lesions. The exact role they pay in affecting the WBC counts remains to be determined.

Tinetti testing associated with chronic venous disorders and injection drug use

  B Pieper, TN Templin, TJ Birk, RS Kirsner
  Persons with history of injection drug use (IDU) are at high risk of chronic venous disorders (CVD). Little is known about the effect of CVD on walking mobility. We examined the relationship between injection drug use, CVD, and walking mobility using the Tinetti Balance and Gait test and walk speed. A test-retest design was used with latent variable structural equation modeling of walking mobility in relation to IDU and CVD. Questionnaires included the Demographic and Health History and Drug History. The lower extremities were evaluated with the clinical portion of the Clinical-Etiology-Anatomy-Pathophysiology (CEAP) Classification. Participants completed the Tinetti Balance and Gait test and a timed 6-meter walk. The participants were 104 men (57.7%) and women from a methadone maintenance treatment center. Thirty-four participants had never injected in their legs and 70 had injected for an average of 22.4 years. Test-retest reliability of the Tinetti Balance and Gait test and walk speed ranged from .79 to .86. Although fall information was not collected, 15% of participants who injected in the legs had a Tinetti score of 19 or less, indicating high risk for falls. Walking speed was at a slow pace of 1.16 miles per hour. SEM modeling showed that the negative effects of injection drug use on walking mobility were mediated by CVD severity. Age was not related to walking mobility, but was related to walking speed. Tinetti Balance and Gait scales and walking speed are reliable and valid measures to use with persons with IDU. Persons with a history of injection drug use are at substantial risk for mobility impairment and mobility related injuries and CVD. Further research is needed about walking mobility CVD in the general population.
  Funding: National Institute of Nursing Research/National Institute of Health (NINR/NIH), R01 NR009264

Clinical utility evaluation of lower extremity wound assessment and healing potential

  Roger B. Schechter, MD; Bradley B. Bailey, MD
  Background: Timely and accurate diagnosis of circulatory status is essential for optimal outcomes in the Wound Care Clinic. Unfortunately, many standard noninvasive vascular testing (NIVT) tools are fraught with limitations. The Ankle-Brachial Index (ABI) is inaccurate in diabetic and dialysis patients with calcified arteries. The Toe-Brachial Index, while potentially more effective in detecting macro-vascular impairment in this population, often cannot be performed due to wound location or previous amputation. Transcutaneous Oxygen Monitoring (TCOM) is time consuming and highly operator dependent. Skin Perfusion Pressure (SPP) and Pulse Volume Recording (PVR) are an alternative for evaluating micro- and macro-circulation with a single device. SPP/PVR versus TCOM/ABI are evaluated to compare the clinical utility of these combined technologies and their ability to accurately predict wound healing.
  Methods and Materials: Prospective, nonrandomized, single-center investigation: Outcomes for 100 patients presenting with lower extremity wounds evaluated.
  Primary objective: To demonstrate a decrease in the test time required to accurately predict wound healing. Patients are followed to 16-weeks or healing (whichever occurs first). Data are currently available for 84 patients.
  Results: Study demographics: male: 47.6%; female: 52.4%. Mean age: 68.8 years (median: 70.5; range: 20-75)–50% with diabetes mellitus (42/84), 16 insulin-dependent. Time utility for assessment of wound healing was notable for a mean SPP/PVR test time of 6.8 minutes (median: 6; range: 3-15) ± SD 2.5 compared to a mean TCOM/ABI test time of 35 minutes (median: 35; range: 25-47) ± SD 5.2. Further, SPP accurately predicted wound healing potential at a rate of 88.9% (32/36) compared to 63.9% (23/36) with TCOM.
  Conclusion: This preliminary data set demonstrates an 80% reduction in mean testing time for SPP/PVR compared to TCOM/ABI. In addition, SPP appears to be more accurate in wound healing prediction. These compelling results substantiate SPP as a highly useful tool for NIVT.

Wound-related pain: the patient experience

  Thomas Serena, MD, Patricia Price, PhD
  As part of an international study (n = 2018, 116 patients (mean age = 63.5, SD = 15.43) from outpatient settings in a mid-Atlantic state (58.6% female) participated in this cross-sectional pain survey. Wounds were categorized into seven groups; most wounds were of venous (n = 37) or unknown (n = 34) origin. For 48% of patients this was their first experience with a chronic wound; mean wound duration for the present ulcer was 21.2 months (SD = 53.6). 30.8% of the patients reported wound-related pain “never/rarely,” 32.7% reported pain “quite often” and 35.6% reported pain “most/all of the time,” 53% reported that the location of the wound pain was “in the wound itself,” 53.7% of patients reported pain “never/rarely” at dressing change, 19.4% reported pain “quite often,” and 26.9% reported pain “most/all of the time” at dressing change. 53.4% reported that the pain lasted for <1 hour following dressing change, while 30% reported pain lasting longer. There were no differences by wound type. Using the McGill short form, the words reported most frequently in the severe category were: “tender,” “ hot-burning,” and “sharp.” Sixty-nine patients reported they took pain medication, 12 of whom felt it did not work – 42% were concerned about the long-term use of analgesia. Pain intensity was reported as a mean of 44.13 (SD = 33.2) on a VAS (0-100) scale. Out of six symptoms associated with living with a wound, pain was given the highest mean score on a 5-point scale (mean = 3). Touching/handling the wound was considered the most painful part of the dressing procedure, followed by cleansing and dressing removal. This may explain why 57% of patients wanted to be actively involved in their dressing change. For many patients (66.7%) the pain at dressing change was considered the most painful everyday situation they faced.

The relationship between anxiety, anticipatory pain, and pain during dressing change in the older population

  KY Woo, J Sadavoy, S Sidani, R Maunder, RG Sibbald
  Pain is a significant concern in patients with chronic wounds. New evidence suggests that anxiety may lower the threshold and tolerance to pain. Using a hierarchical regression model, Aaron et al (2001) demonstrated that increased anxiety on a rating scale was a significant predictor of procedural pain during dressing change in burn patients. However, little is known how anxiety and anticipatory pain are related to procedural pain in patients with chronic wounds. Further understanding of the relationship may provide directions to mitigate pain and suffering in this population.
  Method: The purpose of this study is to evaluate the relationship between pre-dressing change anxiety, anticipatory pain, and pain during the dressing change procedure in the older population. Ninety-six patients with chronic wounds were asked to rate their anxiety level (Spielberger State-Trait Anxiety Inventory short form) and anticipatory pain (0-10 numeric rating scale) before dressing change. Pain levels were measured at dressing removal, cleansing of the wound, and application of dressing.
  Results: Anxiety levels before dressing change were significantly related to anticipatory pain (r = .661), pain at dressing removal (r = .527), and pain at cleansing (r = .436) (all P values < 0.01).
  Findings of this study suggest that the assessment of patient anxiety should be part of chronic wound pain evaluation and management.