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Abstracts

The 22nd Annual Symposium on Advanced Wound Care and the Wound Healing Society Meeting

April 29–29, 2009 Gaylord Texan Hotel and Convention Center Dallas, Texas Of the almost 400 abstracts received for judging, only 24 were accepted for oral presentation. The abstracts for these winning entries are presented here to spark your interest for sessions 29, 30, 31, 42, 43, and 44. Posters that have been accepted for presentation may be viewed throughout the entire meeting; the authors will be available during the scheduled poster sessions (Monday, April 27, 7:30 a.m. to 9:00 a.m., and 7:00 p.m. to 9:00 p.m. at the Poster Gala). Ostomy Wound Management congratulates all SAWC presenters for sharing their cutting-edge research.

Topographical localization of bacterial biofilms in a porcine skin explant wound model
Priscilla Phillips, PhD; Edith Sampson; Gregory Schultz
     The presence of persistent bacterial biofilms is known to contribute to the molecular pathologies of many diseases including periodontitis and cystic fibrosis. Furthermore, evidence continues to accumulate, suggesting that a substantial percentage of chronic skin wounds contain bacterial biofilms. The extreme resistance of bacteria in biofilms to killing by antibodies, phagocytic inflammatory cells, antibiotics, and antiseptics leads to chronic inflammation, which results in elevated levels of proteases and reactive oxygen species that degrade proteins in the wound bed that are essential to healing. At present, the only methods to detect bacterial biofilms in wounds involve techniques that are technically complex and time consuming, which prevents the rapid assessment of wounds for biofilms. Thus, there is a need for a rapid, simple, inexpensive, point-of-care indicator that would detect and localize bacterial biofilms in chronic wounds. Detection of biofilm in a region of a chronic wound would enable more specific and appropriate debridement and treatment of the wound bed. Results of initial experiments with a prototype thin membrane sheet that was pressed onto the surface of pig skin explants with mature Pseudomonas aeruginosa biofilms then briefly exposed to a dye followed by washing produced strong staining of regions of the skin with the mature biofilm. In contrast, only faint staining was produced on the membrane when it was pressed on pig skin explants without biofilm. These initial results suggest it may be possible to generate a “wound biofilm map” that can localize biofilms in regions of a wound bed. Further optimization of the design and performance of the prototype wound biofilm map are underway and will be followed by initial clinical evaluation in patients with chronic wounds.

The combined use of silver dressings and living cell tissue-engineered skin substitutes
Terry Treadwell, MD, FACS; Donna Walker, LPN
     Living cell tissue-engineered skin substitutes are becoming a mainstay in the treatment of diabetic foot ulcers and venous leg ulcers. The combination of additional wound care treatments and dressings with the tissue-engineered skin may seem like a reasonable approach. The effect of this combination therapy has little evidence, and some of the treatments are cytotoxic, causing premature cell death. The combination of a silver dressing and a living cell tissue-engineered skin product is becoming an accepted technique despite warnings that silver may be toxic to rapidly dividing cells and cells grown in tissue culture. To evaluate this technique, we combined a silver dressing with a bilayered living cell tissue engineered skin product.* Fresh, unexpired pieces of the tissue-engineered skin in the media well were covered with a different silver dressing using sterile technique. Each silver dressing was left in contact with the tissue-engineered skin during the course of the evaluation. Biopsies of each piece of tissue-engineered skin were obtained at 24-hour intervals for 7 days. Each specimen was evaluated microscopically and compared to a control not treated with a silver dressing. Results showed that the silver dressings were toxic to the living cells in the tissue-engineered skin product. Time to cell death varied depending on the silver product evaluated. Changes in cell viability could be detected as early as 96 hours after institution of treatment with silver products, and total cell death was noted by 168 hours (7 days). Photomicrographs of the biopsy specimens will be shown, and the effect of different products discussed. Based on these findings, it is not recommended that any wound care product containing silver be used in combination with a living cell tissue-engineered skin product. *Apligraf, Organogenesis, Inc. Canton, Mass (Data on file. Organogenesis, Inc., 1998)

Low frequency ultrasound (35 KHz) reduces prokaryotic and eukaryotic growth, alters cell wall structure and colonial characteristics in vitro
Geleana Drew Alston; Alex Stovall; Tracy Vernon; Devin Winter; Teresa Conner-Kerr
     Results from previous studies support a bactericidal effect of low frequency ultrasound (LFU) delivered at 40 KHz on bacteria including methicillin-resistant Staphylococcus aureus (MRSA).

     Purpose: The purpose of this study was to determine the effects of LFU delivered at 35 KHz on the viability and cell wall structure in vegetative forms of the prokaryotes (MRSA, Pseudomonas aeruginosa [PA]) and the eukaryote, Candida albicans (CA).

     Methods and Results: Known isolates of MRSA, PA, and CA from patient lower extremity wounds were subcultured, plated, and grown on sheep blood agar (SBA). Using sterile saline, serial dilutions of the organisms were made and treated for 30, 60 and 180 seconds. One hundred microliters (µl) of control (untreated organisms) and treated samples were inoculated to SBA in triplicate. Aliquots from the untreated and treated samples also were taken for scanning electron microscopy (SEM). A 66% reduction in MRSA colony-forming units was detected after 30 seconds of treatment with 35 KHz LFU. Similar results were found with LFU treatment of PA and CA. PA appeared to be most sensitive to the effects of the LFU treatment. SEM revealed alterations in cell wall structure. LFU treated MRSA demonstrated changes in the colonial characteristics: pigmentation, odor, colony size, and hemolysis pattern.

     Discussion: The data suggest that LFU reduces colony-forming units of the treated bacteria, fractures cell walls, and alters colonial characteristics of MRSA.

Assessment of antimicrobial dressing efficacy on mature PAO1 biofilm cultured on porcine skin explants
Gregory Schultz; Priscilla Phillips; Qingping Yang; Edith Sampson; Patrick Antonelli
     Purpose: Formation of biofilm matrix provides substantial protection for bacteria to environmental stresses as well as host antibodies, phagocytic inflammatory cells, antibiotics, and antiseptics. The presence of persistent bacterial biofilms contributes to the molecular pathologies of many diseases and recently has been recognized as one of the main factors contributing to delayed wound healing. Biofilm development is a complex process greatly influenced by the bacterial microflora, the environment, and the substrate to which it attaches. The study of biofilms in wound healing would benefit from models that mimic the physiology of human wounds. We developed an in vitro porcine skin explant biofilm model and used this model to assess efficacy of commercial antimicrobial dressings.

     Methods: Sterilized fresh porcine skin explants with partial-thickness wound beds were inoculated with early log phase bacterial culture of Pseudomonas aeruginosa PAO1. After 3 days of growth, the explants with mature biofilms were treated overnight in liquid media containing 200 Œºg/ml gentamicin antibiotic (100 MIC) to kill all planktonic bacteria. Test dressings then were applied to the mature biofilms, and after 1 to 3 days of further culturing, the explants were sonicated and CFU of biofilm bacteria were determined by serial dilution spread plating.

     Results: Four types of antimicrobial agents (iodine, silver, polyhexamethylene biguanide [PHMB], and doxycycline) and three types of moisture dressings (cotton gauze, sodium carboxymethlcellulose hydrofiber, and calcium algisite fiber), were assessed. Cadexomer iodine had a 100% kill of POA1 biofilm. Silver, doxycycline, and PHMB dressings reduced biofilm bacteria levels ~1 to 2 logs (from ~108 to 106 CFU). Algisite fiber dressing promoted PAO1 biofilm growth ~1 to 2 logs.

     Conclusion: This model suggests that antibiotics, silver, and PHMB are ineffective in killing existing mature bacterial biofilm. Cadexomer iodine appears to be an effective antimicrobial wound dressing.

Do relationships with others influence the perception of anxiety and pain in patients with chronic wounds?
Kevin Y Woo; Joel Sadavoy; R. Gary Sibbald; Souraya Sidini; Robert Maunder
     Pain is a complex but common concern in patients with chronic wounds. A burgeoning body of evidence suggests the intricate relationship between anxiety and pain. In this study, the attachment framework was examined to determine how personal views of self (attachment anxiety) and others (attachment avoidance) may construct the pain experience during dressing change. Attachment style differences have been found in systematic patterns of expectations, emotional reactivity, strategies for distress management, and social behavior based on an individual’s belief about the self and others. The purpose of this study was to explore the relationship of attachment style and the experience of pain in terms of anticipatory pain, self-reported pain, and behavioral expression of pain in a population of older adults during wound dressing changes. In this cross-sectional study, 96 older patients were asked to respond to a questionnaire that classified them into four different categories of attachment styles. Patients were asked to rate their levels of anticipatory pain and actual pain levels at different times during wound care using a numerical rating scale.

     Repeated Measure Analysis of Variance (RM-ANOVA) was used to detect the differences in pain ratings before, during, and after dressing changes. Post-hoc comparisons were performed using paired t-test to determine the time point at which pain scores differed. ANOVA was used to detect differences in anticipatory pain, anxiety, and pain during dressing change among the four attachment groups. Post-hoc analysis using Scheffe tests was used to identify which groups differed on these variables. To test the mediating effect of anxiety between attachment and pain, multiple regression analyses were used. Results indicated that patients experienced more pain during dressing change than at baseline (t-tests, P <0.001). Secure subjects reported less pain and anxiety than subjects with other attachment styles (ANOVA, P <0.001). Results of regression analysis indicated that anxiety mediated the relationship between attachment and pain.

     Results of this study also support the role that attachment plays in the experience of pain in older adults. Clinicians must be cognizant of the impact of personality, anxiety, and anticipation of pain on actual pain experience.

A crossover clinical study of 47 patients with painful deep wounds showed topical hydrogel application was highly significant in alleviating dressing-related pain
Brad Pontani, MD, FAAFP, CWS, ABPM/UHM; M. Feste, CHRN, CWS; C. R. Adams, ACHRN, CWS; K. Lloyd, MS; J. B. Spalding
     Introduction: Surveys of patients with deep wounds express that the time during dressing changes is the most painful aspect of living with a deep wound. The National Pain Care Policy enacted by Congress in 2007 states that pain is often improperly addressed and often undertreated. Wound dressing procedures such as compression wraps, wet-to-dry packing, enzymatic debriding agents, and negative pressure wound therapy can cause moderate to extreme pain. Surveys have shown dressing change pain can last more than 5 hours. The use of an FDA registered hydrogel containing 2% lidocaine could provide a substantial matrix when used as a contact layer to help reduce pain during and after dressing change.

     Methods: Forty seven subjects (ages 20 to 91 years) with painful venous ulcers, infected wounds, and pressure, diabetic foot, surgical, or trauma wounds were evaluated for dressing related pain using a numeric pain score 0 to 10 (least to worst). Subjects received an advanced wound dressing treatment selected by the physician. Patients rated the pain level of dressing change without use of the lidocaine hydrogel and were crossed over to receive the hydrogel (aloe, collagen, and 2% lidocaine) under the wound dressing during subsequent dressing changes. Patient pain scores were assessed and recorded.

     Results: Pain score analysis showed 4.5 levels of pain reduction with the use of the lidocaine hydrogel as compared to no treatment. Statistical evaluation of pain score differences with use of the hydrogel as compared to control were analyzed by the Sign Test (chi square = 21.511) and by the Wilcoxin Matched Pairs Signed Ranks Test. Both tests showed P <.00001 in significance.

     Conclusion: The hydrogel- lidocaine product reduced pain by a highly significant amount when applied as a contact layer during a variety of dressing changes. No untoward side effects were noticeable in this study. Physicians and nurse practitioners can use a hydrogel that greatly eases the pain of dressing change for most patients, encouraging a less anxious experience for practitioners and patients.

Peristernal laser Doppler flowmetry improves with negative pressure wound therapy
B. Zane Atkins, MD; Jean K. Tetterton, NP; Kista Hurley, PA-C; Walter G. Wolfe, MD
     Background: We previously described the successful use of negative pressure wound therapy (NPWT) as a form of well wound therapy after cardiac surgery via median sternotomy in high-risk patients.

     We evaluated NPWT’s effect on laser Doppler flowmetry readings in the presternal area after median sternotomy. This method has been reliable in evaluating regional blood flow in other models.

     Methods: 12 patients underwent median sternotomy for cardiac surgery (April to September 2008). NPWT was implemented upon the clean, closed incision in eight patients after surgery, as previously described (treatment group). Among controls (n = 4), the sternotomy was closed, and a clean, dry dressing was applied. Laser Doppler flowmetry (LDF; Laserflo BPM2, Vasamedics, St. Paul, Minn.) monitoring was performed at baseline, 4 hours after surgery, and daily for 4 days postoperatively. LDF was performed with 10-second averaging and a P-430 right-angle probe. Measurements were taken at multiple levels across the pre-sternum. Results for the treatment group were compared with controls using ANOVA.

     Results: All patients underwent successful cardiac surgery via sternotomy. Patients in the treatment group were at increased risk for postoperative mediastinal wound complications based on obesity, diabetes, and other comorbidities. NPWT continued for 4 days postoperatively in treatment group. No cases of sternal wound complications were encountered in either group. LDF was decreased after surgery in both groups relative to baseline P <0.05). In the treatment group, LDF increased postoperatively, corresponding with use of NPWT (pP <0.05). LDF was unchanged across the study period in controls.

     Conclusions: This is the first known description of LDF assessment in the presternal area after cardiac surgery with sternotomy. NPWT, which has been correlated with reduced observed rates of sternal infection, appears to increase LDF relative to controls. Further consideration should be made for use of NPWT in those with risk factors for sternal wound complications.

Early intervention using V.A.C. Therapy. Does it make a difference in compartment syndrome?
Michael N. Desvigne, MD, FACS; Kerry Grant, WOCN; Peggy Downs, RN, BSN
     Introduction: Negative pressure wound therapy with reticulated open cell foam (NPWT/ROCF) as delivered by V.A.C. Therapy (KCI Licensing, Inc., San Antonio, TX) has become increasingly recognized as a new standard of therapy for difficult wounds such as compartment syndrome. Compartment syndrome usually occurs following injury or surgery in which excessive fluid accumulation causes increased pressure within the compartment and impairs blood flow.

     Rationale: Early initiation of NPWT/ROCF may be beneficial in the management of patients with compartment syndrome requiring fasciotomy. The ability to seize the natural process of edema progression and ischemia is paramount in the effective management of these patients. Early initiation of NPWT/ROCF may effectively enhance treatment and increase the probability of limb salvage. Additionally, with early intervention, the probability of secondary closure is enhanced and the need for skin grafting may be reduced.

     Methods: A retrospective review of eight patients with compartment syndrome requiring fasciotomy was performed over 2 years.

     Results: Patients treated within 6 hours of diagnosis received fasciotomy and early initiation of NPWT/ROCF. All patients survived and all limbs were salvaged. Only two patients required skin grafting; however, the size of the wound was significantly reduced with 6 weeks of NPWT/ROCF.

     Conclusion: Early initiation of V.A.C. Therapy in patients with compartment syndrome requiring fasciotomy may significantly enhance patient outcome. Limb salvage may be enhanced as V.A.C. Therapy effectively reduces edema and promotes perfusion. Early initiation provides maximum benefit in reducing the cycle of ischemia progression and enhancing limb salvage.

Study of human lactoferrin in keratinocytes migration and attachment
Ling Tang, PhD; James J. Wu; Ning Huang, PhD; Jie Li, MD, PhD
     Purpose: Human lactoferrin (hLF), an iron-binding glycoprotein, has been reported to have antimicrobial and immunoregulatory functions. However little is known about its therapeutic effects on wound healing. This study was conducted to determine the effects of rice-derived holo-recombinant human lactoferrin on human keratinocytes migration and attachment, which are key steps in wound reepithelialization.

     Methods: Keratinocyte migration was evaluated by an in vitro incisional wound model-scratch migration assay. Cells were grown to confluence in six-well plates. A cross-shaped wound gap (the no cell zone) was made by scratching with a pipette-tip across the monolayer cells. Cells then were cultured in growth medium with various concentrations of hLF (0, 10, or 100 Œºg/mL). Cell migration (gap filling) was recorded every 24 hours under a phase-contrast microscope and quantified by the time and percentage of the gap filled. Cell attachment was conducted by seeding 80,000 cells/well in 96-well plate, incubated for 15, 30, or 45 minutes in keratinocyte basal medium with various concentration of hLF (0, 100, or 200 Œºg/mL) and analyzed with a colorimetric method at OD 570 nm.

     Results: Migration: Our data showed hLF significantly promoted keratinocyte migration. At day 3, gap filling was increased 10.41% (P <0.01) and 10.25% (P <0.01) in cells cultured with 10 and 100 Œºg/mL of Hlf, compared with cells without hLF. At day 4, cells treated with 100 Œºg/mL hLF had significant higher gap filled compared to cells without hLF (95.05% vs. 84.38%, P <0.01). Attachment assay: No significant difference was observed in the cell attachment.

     Conclusion: In nonhealing wounds, keratinocyte migration is impaired, which is possibly due to unresponsiveness of the cells to growth factor activation signals. Our results showed that hLF has direct stimulating effects on keratinocyte migration, indicating its high potential of therapeutic application in chronic wounds.

Oxygen reservoir dressing sustains elevated wound PO2 after hyperbaric oxygen treatment
Harriet Hopf, MD; Gerit Mulder, DPM; Jay Duchnick, CHT; Scott Barnhill, AS, SRS, RLATG
     Background: The benefits of hyperbaric oxygen therapy (HBOT) for wound healing are well-established. They result from the oxidant effects of oxygen and biologic processes for which oxygen is a rate-limiting step. Although the major benefits of HBOT clearly result from systemic oxygen delivery, the potential benefits of topical oxygen are also of interest. We evaluated an oxygen reservoir dressing (OxyBand™) for its ability to maintain elevated levels of dissolved oxygen (PO2) in wounds after HBOT. Oxygen delivery by the dressing is diffusion-driven, saturating wound fluid and then replacing oxygen as it is consumed using a bilayer reservoir that stores oxygen gas between a high transmission rate film over the wound and an occlusive film.

     Methods: With IACUC approval, eight standardized full-thickness wounds were created on the backs of two pigs (one control, one HBOT). The wounds were covered with either thin film (four per pig) or OxyBand™ (four per pig) dressings. Oxygen levels at 2-mm depth within the wound exudate were measured 3, 8, 11.5, 14, and 16 hours after dressing placement and 15 minutes, and 2, 6, and 12 hours after HBOT using polarographic microelectrodes.

     Results: With the pigs intubated and anesthetized (FiO2 1.0), the PO2 ranged from 81 mm Hg to 106 mm Hg under the control bandage and 160 mm Hg to 228 mm Hg under the test bandage. PO2 was 256 mm Hg to 260 mm Hg under both dressings 15 minutes after HBOT. At 2 to 12 hours after HBOT, PO2 was 89 mm Hg to 125 mm Hg under the control bandage and 245 mm Hg to 263 mm Hg under the test bandage.

     Conclusions: The OxyBand™ reservoir dressing maintained elevated wound oxygen levels after HBOT, demonstrating that the dressing was able to replenish oxygen levels as it was consumed locally. Potential synergies of providing the systemic benefits of HBOT and extending the local benefits of hyperoxia using an on-demand oxygen reservoir dressing warrant further investigation.

Human skin survives for months in sodium chloride and can be successfully transplanted
Waldemar L.Olszewski; Maria Moscicka; Dorota Zolich
     Introduction: We have been searching for methods of long-term preservation of skin for transplantation (tx). Because epidermis and underlying dermis are, relatively to other tissues, resistant to ischemia and dehydration, we tried to use dehydration method for preservation of skin fragments and tx.

     Aim: To prove that fragments of skin dehydrated in powdered anhydric sodium chloride can retain their vital properties and can be successfully tx.

     Methods: Human skin fragments (n = 30) from lower limbs were harvested during elective vascular surgery, then placed in heat-dried fine sodium chloride powder (1 part skin, nine parts NaCl) and kept at room temperature for 3 to 6 months. Subsequently, they were desalinated and 1 cm x 1 cm fragments were tx to dorsum of scid mice (60). After 3 weeks to 3 months, grafts were harvested. In two patients, fragments of skin were taken during limb debulking surgery, preserved and tx onto nonhealing parts of wounds.

     Results: All grafts took. On histology, keratinocytes looked normal. They were all HLA class I. Staining with mAbs against human keratinocyte stem cells p63, CD29 (transient cells), PCNA (proliferating cell nuclear antigen) revealed normal pictures of basal layer cells. BdUr injected 24 hours before harvesting stained a number of nuclei of basal cells. Staining against mouse MHC I and II antigens, macrophages, and granulocytes did not reveal the presence of mouse antigens in tx human epidermis. In dermis, fibroblasts looked normal with some large HLA DR+ cells in intercapillary spaces. Both grafts put on the nonhealing human wounds took and became hypertrophic after 3 months.

     Conclusions: Human skin survives in a dehydrated state for months and upon tx gives rise to keratinocyte progenies. 

A study to compare the effectiveness of honey dressing vs. povidone iodine dressing in chronic wound healing – a prospective, randomized study
Sonia Gulati; Anurag Srivastava
     A prospective, randomized control trial was conducted at Aiims, India from June 2008 to December 2008 in a wound care clinic, surgical outpatient department, and APEX trauma center. The study compared the effectiveness of a honey dressing vs. a povidone iodine dressing in chronic wound healing. A total of 45 subjects with different types of chronic wounds including venous, arterial, pressure ulcers, diabetic, traumatic and stasis dermatitis, located on different parts of the body, were enrolled into the trial based on the inclusion criteria. Subjects were randomized into two groups of dressing by using computer-generated table of random numbers. Random assignment was done by numbered sealed envelopes — 23 patients were in honey dressing group and 22 patients were in povidone iodine dressing group. Dressing was done for 6 weeks on an alternating basis and wound healing observations included wound perimeter drawn on the transparent acetate sheet, wound culture swab, and pain; comfort in both groups was assessed with the help of pain-rating scale. Computer image analysis of the scanned transparent acetate sheet identified the maximum diameter, surface area, and perimeter of the chronic wound. Statistical analysis of the whole data shows significant differences between the two groups at the end of the 6 weeks: in terms of decrease in surface area (P = 0.0062), perimeter (P = 0.0070), maximum diameter (P = 0.0062), infection rate (P = 0.0155) , pain level (P = 0.0001), overall comfort (P = 0.000) where P value <0.05 was considered to be significant study is part of thesis work by the investigator.

Evaluation of Apligraf for treatment of diabetic foot ulcers of the heel
Hau Pham, DPM; Christopher Locke, DPM; Susan Walsh, DPM; Gary Gibbons, MD; Vickie Driver, DPM; Geoffrey Habershaw, DPM
     Objective: Diabetic ulcers of the heel are especially difficult to close. We wanted to evaluate the efficacy of Apligraf, which is approved for diabetic foot ulcers in general, in a heel-specific study.

     Methods: We performed a retrospective study to identify and evaluate treatments utilized for patients with diabetic heel ulcers from January 2007 to June 2008 at the Boston Medical Center Podiatry Clinic. We compared ulcers treated with Apligraf to those treated with other products. All patients had initial debridement and frequent follow-up visits.

     Results: 21 patients were treated with Apligraf, and 13 patients were treated with other wound care products. Application of a second piece of Apligraf was considered after 3 weeks, and an average of two pieces were used to treat heel ulcers. Of the 13 patients not treated with Apligraf, two received major amputations within 12 weeks and a third developed a severe infection requiring incision and drainage and partial calcanectomy. No such outcomes were noted in the Apligraf group.

     The average ulcer size for the Apligraf-treated group was 16.3 cm2; those who did not receive Apligraf averaged 24 cm2. Ten of the 21 patients who received Apligraf achieved complete wound closure by week 12, compared to none of the 13 patients not receiving Apligraf. Patients who did not reach complete closure within 12 weeks did better if they received Apligraf. The wound area was reduced by an average of 72% in these patients at 12 weeks, compared to 56% in patients treated with other products.

     Conclusions: Apligraf is more effective in the treatment of hard-to-heal diabetic ulcers located on the heel than other products utilized, in terms of both complete wound closure and reduction in wound area.

Epidemiology and prevalence of methicillin-resistant Staphylococcus aureus and Staphylococcus epidermis in patients with diabetic foot ulcers: focus on the differences between species isolated from individuals with ischemic versus neuropathic foot ulcers
Hanna Galkowska; Adrianna Podbielska; Waldemar L. Olszewski; Ewa Stelmach; Miroslaw Luczak; Grzegorz Rosinski; Waldemar Karnafel  
   The mechanism of microbial colonization of diabetic foot ulcer (DFU), selectivity of bacterial species, and acquired resistance to antibiotics remains unclear. We sought to determine whether foot ischemia or neuropathy promote selection of staphylococci species, to evaluate frequency of MRSA and MRSE among strains yielded from patients with DFU, and to assess multidrug-resistant isolates. Patients with DFU and clinically suspected osteomyelitis (foot lesions of grade 3 on the Wagner classification system) were divided into ischemic foot ulcer (IFU, n = 21) and neuropathic foot ulcer (NFU, n =2 9) groups according to peripheral sensory neuropathy and arterial perfusion assessment. Microbiological samples were collected and staphylococci species were assessed using microbiological and molecular methods. S. epidermidis was isolated more frequently from the toe web surface of patients with IFU compared with NFU (55% vs. 17.9%, respectively) and healthy volunteers (HV, n = 20) (17.6, P <0.05). Frequency of S. epidermidis yielded from curettage of IFU was also higher compared with NFU (P <0.05). These mostly MRSE strains differed in their susceptibility to antimicrobials and were multidrug resistant (88.8%). Also, most of MRSA isolates were multidrug resistant (70.3%). Higher percentage of MSSA from DFU revealed resistance to antimicrobials compared with MSSA from HV. The PVL virulence genes were detected in 11.1% of studied MRSA strains. This is the first report indicating that diabetic patients with IFU differ in higher frequency of S. epidermidis infection of ulcer and skin colonization compared with NFU patients. We suggest that IFU should be defined as separate disease state of DFU and S. epidermidis should be appreciated as nosocomial pathogen.

Evaluation of healthcare utilization and costs for hospitalizations and surgical procedures in patients with diabetic foot ulcers treated with V.A.C. Therapy versus advanced moist wound therapy
Vickie R. Driver, MS, DPM, FACFAS; Charles Anderson; Gerry Oster; Charu Taneja
     Background: A multicenter randomized clinical trial (RCT) assessed efficacy and safety of negative pressure wound therapy using reticulated open-cell foam (NPWT/ROCF) as delivered by V.A.C. Therapy (KCI Licensing, Inc., San Antonio, TX) versus advanced moist wound therapy (AMWT) in adult patients with diabetic foot ulcers (DFUs). NPWT/ROCF was reported to be as safe as and more efficacious than AMWT (eg, hydrogels and alginates). The current study evaluated healthcare utilization and costs for hospitalizations and surgical procedures between patients randomized to V.A.C. Therapy (n = 162) versus AMWT (n = 162) in the above RCT.

     Methods: Randomized study subjects were followed 2 weeks post wound closure or end of active treatment phase (ATP), whichever occurred first. Attention was focused on all acute inpatient services used, including wound-related surgical procedures. Unit costs (expressed in 2007 dollars) were assigned using secondary data sources. Mean estimated total costs were determined by total inpatient costs divided by total number of randomized and treated patients per study arm.

     Results: Acute care hospital admissions for NPWT/ROCF patients were 34/162 (21%) compared to 53/162 (32%) for AMWT patients. There was a statistically significant difference between average number of admissions per patient: NPWT/ROCF, 0.21; AMWT, 0.33 (P <0.05). During ATP, there were fewer amputations in the NPWT/ROCF group (six versus 11 for AMWT). NPWT/ROCF mean estimated total costs of inpatient services were $5,206 (95% CI: $3,172, $7,561) versus $8,570 ($5,922, $11,432) for AMWT, a difference of $3,364 per studied patient.

     Conclusions: During the active treatment phase of this RCT, patients with DFUs treated with V.A.C. Therapy had fewer hospital admissions and amputations, resulting in lower costs related to hospitalizations and surgical procedures compared to patients treated with AMWT.

Objective outcome evaluation of Charcot foot reconstruction by monitoring dynamic behavior of plantar pressure
B. Najafi, PhD; R. Crews, MS; M. Bharara, PhD; J. Wrobel, DPM, MS; L.C. Rogers, DPM; D.G. Armstrong DPM, PhD
     Objective: The optimal surgical approach for Charcot foot reconstruction is a hotly debated topic among foot and ankle surgeons. Although many studies have proposed plantar pressure magnitude (PPM) as a surrogate measure of trauma to the plantar foot, the current evaluation methods suffer from various shortcomings. In other words, following surgery, patients may increase their gait speed in response to greater confidence in stability and a more efficient gait pattern. Although this increase may be practically advantageous, it also may result in increased PPM, historically viewed as a negative outcome. This study aims to develop a novel assessment protocol, which is speed-independent and can reliably screen dynamic plantar loading in patients with Charcot reconstruction.

     Methods: A time-scale normalization scheme was used to moderate the effect of gait speed. To examine whether the plantar pressure distribution (PPD) measured using EMED plantar pressure system, was normal, a customized normal distribution curve was created for each trial. Then the original PPD was fitted to the customized normal distribution curve. This technique yields a regression factor (RF), which represents the similarity of the actual pressure distribution with a normal distribution. RF values may range from -1 to +1 and as the value increases positively so does the similarity between the actual and normalized pressure distributions. We tested this novel score on plantar pressure pattern of healthy subjects (N = 15), Charcot pre-operation (N = 3), and Charcot post foot reconstruction (N = 1).

     Results: In healthy subjects, the RF was 0.46±0.1. When subjects increased their gait speed by 25%, the PPM was increased by 8% (P <0.0001, paired t-test), while RF was unchanged P = 0.7). In preoperative Charcot patients, the RF <0; however, RF increased post surgery (RF = 0.47), indicating a transition to normal plantar distribution after Charcot reconstruction.

     Conclusion: Our results demonstrate that although peak of plantar pressure may recognize the abnormal dynamic loading in Charcot patients compared to healthy subjects, it is unable to screen improvement post Charcot reconstruction surgery. To overcome this shortcoming, we suggest a reliable and speed-independent score to demonstrate gait improvement. Further testing involving both barefoot as well as in-shoe conditions may elicit a clinical measure and may be integrated into a pervasive healthcare regimen involving virtual clinics and telemedicine platform.

Topical active Leptospermum honey in recalcitrant venous leg wounds: a preliminary case series
Jason R. Hanft, DPM; Tanisha Smith, DPM; Kennedy Legel, DPM; T. Smith; K. Legel
     Purpose: To investigate the use of active Leptospermum honey* -impregnated calcium alginate dressings (HICADs) in a series of patients with bacterially burdened recalcitrant venous ulcerations that failed to respond to an assortment of therapeutic modalities including four-layer compression, topical silver, nonadherent dressings, and antibiotic therapy.

     Methods: The protocol design included application of active Leptospermum HICAD and a multilayer compression dressing once weekly. The inclusion criteria stated nonhealing ulcerations with confirmed venous incompetence and insufficiency via ultrasound imaging. Eleven patients were enrolled and treated until the wound closed or for 3 to 6 weeks, with applications of active Leptospermum HICAD and a multilayer compression bandage that was changed on a weekly basis.

     Outcome: Eleven patients with chronic recalcitrant lower extremity venous wounds demonstrated an increased velocity of healing. Complete wound closure was achieved within 3 to 6 weeks for all patients.

     Conclusion: The result of this case series confirms existing evidence of the beneficial effect of active Leptospermum HICADs to heal chronic wounds that are unresponsive to traditional therapies. This treatment provides another tool and may prove to be an alternative therapy for difficult-to-treat wounds that do not respond to first-line therapy.

The effectiveness of bilayered cell therapy in the treatment of chronic venous ulcers
Caroline Fife, MD; David Walker, CHT; Gordon Otto, PhD; Brett Thomson; Margaret Grasso, MS
     The objective of this study was to evaluate the effectiveness of bilayered cell therapy (BCT) in chronic venous leg ulcers (VLU) among patients seen at hospital-based outpatient wound centers.

     Demographics, comorbidities, ulcer characteristics, treatment, and outcome of patients with VLU presenting to US wound centers were retrospectively analyzed using the Electronic Medical Records of 17,160 patients collected between January 1, 2001 and May 8, 2008 from the Intellicure Research Consortium database. Twenty-six outpatient wound centers in 16 states across the US were included in the study.

     2,139 patients presented with 4,364 venous ulcers. Mean patient age was 68 years (range 18 to 102 years) with an average of 9.5 comorbid medical conditions, primarily hypertension (35%) and diabetes (32%, of which 86% type II). BCT was applied to 169 venous ulcers (3.87%) on 110 patients (5.1%). Mean ulcer duration prior to wound center consultation was 122.4 weeks. A mean of 35.6 weeks of care within the wound center occurred prior to application. Mean ulcer surface area was 21.3 cm2 at presentation and 13.5 cm2 at BCT application. An average of 1.7 BCT applications were performed per ulcer with a mean of 31.9 days (range 3 to 134 days) between applications. BCT were fenestrated 51% of the time and secured by a soft silicone contact layer 56.4% of the time. Success was defined as a wound size <0.2 cm and absence of exudate or a clinician-reported outcome of healed, healing, improved, improving, or epithelialized. Although outcome information was not available in 30% of cases, when known, BCT was deemed successful in 95% of cases, despite a mean duration at presentation of more than 2.3 years and many serious comorbid medical conditions. These results depict effectiveness in real world clinical conditions.

Comparison between two methods of wound measurement on wound models: actetate tracing* and a hand-held, electronic wound measurement device
Mark A. Nixon; Bruce L.K. Davey; W. Richard Fright; Bruce C. McCallum; David C. Kieser
     Aim: To compare accuracy and repeatability of conventional transparent, acetate film tracing with a hand-held, electronic wound measurement and documentation device on wound models.

     Methods: Discs of known area were placed at various locations on a mannequin leg. The surface area of each disc was measured five times with the hand-held, electronic wound measurement device and five times via acetate tracing, where the area from the acetate film was derived using a digitizing tablet. For both methods, the mean error, standard deviation, and maximum error were calculated for each disc.

     Three wound models of known depth were constructed. The depth of each was measured five times with the hand-held, electronic wound measurement device, and the mean error, standard deviation, and maximum error were calculated for each model.  

   Results: For the electronic device, the largest mean error and largest standard deviation of the five area measurements on any one disc were 1.5% and 0.5%, respectively. The largest error of any single area measurement was 1.9%.

     By comparison for transparent film tracings, the largest mean error and largest standard deviation on any one disc were 2.6% and 2.7%, respectively. The largest error of any single area measurement was 6.1%.

     The largest mean error and largest standard deviation of the five depth measurements on any one model using the electronic device were 0.8% and 0.4%, respectively. The largest error of any single depth measurement was 1.3%.

     Discussion: The hand-held electronic wound measurement device was shown to measure area and depth of wound models more accurately and repeatedly than conventional acetate tracing. *ARANZ Medical SilhouetteMobile™, ARANZ Medical Limited, Christchurch, New Zealand

Can THIS be lymphedema?
Suzanne Ehmann, PT DPT/CWS/CLT-LANA
     There is a considerable lack of attention in the medical community with regard to the incidence of secondary lymphedema and available treatment options. Often medical providers are resistant to entertain the diagnosis of lymphedema unless the patient has a history of cancer. A closer examination of the anatomy and physiology of the lymphatic system demonstrates that any number of pathologies can impair lymphatic function. Impairment of the lymphatic system can not only present as edema, but also display significant trophic changes, delayed wound healing, and chronic infections that may significantly decrease a patient’s functional mobility and quality of life. The purpose of this presentation is to highlight three different underlying pathologies leading to lymphedema. Included is how these underlying pathologies lead to lymphatic impairment, as well as the treatment approach used to achieve volume reduction, wound healing, and significant tissue improvements. Pathologies to be discussed include: venous insufficiency, lipedema, and chronic cardiac edema and the successful management of lower extremity edema and trophic changes utilizing complete decongestive therapy (CDT). Pictures and graphs to be presented outlining findings pre- and post-treatment support the success of this treatment approach. 

Impact of linen layers on pressure and skin microclimate
Rachel Williamson, BSBM
     Adding layers of linens under the patient may inhibit the surface’s ability to redistribute pressure and maintain an optimal skin microclimate. The purpose of the study was to quantify the change in interface pressure and low-air-loss performance with various linen layers on an air and foam surface.

     A sensored pelvic indentor was used to measure the peak sacral and overall average pressure in mm Hg. Ten trials were performed at 0 degrees, 30 degrees and 45 degrees head of bed elevations with five linen configurations. Loads were adjusted appropriately. ANOVA was performed followed by the Fisher-Hayter test to determine statistical differences at a 95% confidence level.

     The surface’s ability to withdraw heat and moisture was measured using a technique adapted from the outdoor garment industry known as the sweating guarded hot plate method. Six dry and six wet trials were performed at 0¬∞ head of bed elevation with six linen configurations.

     A fitted sheet on an air and foam surface produced the lowest peak sacral pressures. Adding a chux, slider sheet, or disposable pad produced a statistically significant increase in peak sacral pressure on both surfaces. No statistical difference in the overall average pressure was measured for both surfaces.

     The air-loss surface with a sheet produced the highest total heat withdrawal and evaporative capacity. The addition of a disposable pad or slider sheet did not significantly degrade the heat and moisture withdrawal capability of the surface. The chux and multiple linen layers significantly decreased the heat withdrawal and evaporative capacity of the surface.

     Pressure and skin microclimate are critical factors that contribute to skin breakdown. Depending on the type of linen under the patient, the peak sacral pressure can significantly increase and decrease the microclimate management capabilities to that of a non-low-air-loss surface.

Safety of deep debridement with anesthesia in the operating room
Daniel K. O’Neill; Pavandeep Bagga; Fay Marie Hall; Lisa Draghi; Diane Stella; Jason Maggi; Harold Brem
     It is our hypothesis that wound management with deep debridement can be done safely and efficiently in the operating room with anesthesia services.

     In a subset, 57 patients with 82 wounds underwent 200 anesthetics in the main operating room for wound management. Monitored anesthesia care (MAC) (local with or without sedation) was used in 47 cases, general anesthesia was used in 37 cases, and regional anesthesia was used in 24 cases (nerve block = 11, spinal = 11, and epidural/spinal = two). Airway management techniques included face mask, oral airway, nasal airway, laryngeal mask airway, and endotracheal tubes. Common agents used were propofol, midazolam, fentanyl, ketamine, and sevofllurane. Less than 15% of cases required neuromuscular blockade. Intravenous anesthesia was more commonly used than inhalational anesthesia. Regional anesthetic techniques include central neuroaxial blockade (spinal and epidural), brachial plexus block, sciatic block, popliteal block, and ankle block using lidocaine, mepivacaine, and/or bupivicaine. In two patients, inhalational induction with nitrous oxide and sevoflurane was used to sedate prior to securing vascular access. In one patient, an awake, locally anesthetized central venous catheter was placed for vascular access. Approximately 10% of patients had PICC lines in situ and 90% of the inpatients had heplocks in situ prior to arriving to the OR. Approximately 15% of the patients were phlebotomized in the operating room for the processing of platelet gel. The age of the patients ranged from 8 to 101 years. The anesthesia services were provided by 30 different attending anesthesiologists.

     Results: In 200 cases, there were no anesthesia-related deaths, myocardial infarctions, strokes, or other major complications. There was a minor case of epistaxis in a patient requiring nasal airway for snoring during deep sedation. There were no reports of postoperative delirium. The average anesthesia time was 1.8 hours, but with two outliers over 4 hours in duration. Gender and patient age do not correlate with duration of anesthesia.

     Linear model: Time = 1.8178 (0.0006)(Age) has r = -0.016 with coefficient of determination = 0.03%.

     Conclusion: Wound management in the operating room provides excellent operating conditions including illumination, exposure, hemostasis, instrumentation, and support staff. Patient safety is improved with an anesthesia care team dedicated to maintaining homeostasis during surgical stimulation and throughout the perioperative period.

Creating an evidence-based pocket reference guide for pressure ulcer prevention and treatment
Linda Benskin, BSN, RN, SRN (Ghana), CWCN, CWS, DAPWCA; Judy Bolhuis, BS, NHA
     Problem: More than 2,400 research articles have been published and at least a dozen evidence-based guidelines for prevention and treatment have been distributed, but pressure ulcers are still a global health concern. Evidence-based information for the prevention and treatment of pressure ulcers has not been integrated and made available to bedside caregivers in a convenient form.

     Objective: Our goal was to create a comprehensive, but succinct, evidence-based reference tool for the prevention and treatment of pressure ulcers to guide bedside practice.

     Methods: Information from a thorough review of the literature, with an emphasis on evidence-based guidelines and textbooks, was distilled into a single comprehensive footnoted pressure ulcer educational piece. This information was further summarized, using well-recognized tools when available, and compiled into a laminated 4 x 6 pocket guide. The guide includes a pressure ulcer risk assessment scale, positioning information, pain scales, staging guidelines, a wound assessment guide, a dressing selection guide, and a healing assessment scale.

     Results: The pocket guide is distributed to clinicians as a memory aid to be used following the completion of the comprehensive pressure ulcer prevention and treatment educational program. Explanatory text is minimal; the pages are uncluttered and are carefully designed to draw attention to key points. The initial response from clinicians has been very favorable.

     Conclusion: Previously published reference materials for pressure ulcer prevention and treatment are either far less comprehensive than this effort (usually a single laminated page) or they are so wordy that they cannot be referred to quickly at the bedside. By combining tools for assessing pressure ulcer risk, prevention techniques, assessing pressure ulcer wounds and treating those wounds into one concise pocket guide, the authors anticipate increased application of the extensive body of evidence-based pressure ulcer research among bedside caregivers.

Nutrition screening in an outpatient wound center: a pilot screening tool validation
Talisha Cottingham, MSN, CNS; Carolyn Jo Williams, RD, MS; Nancy Beinlich, BSN, RN, CWON; Kimberly Blasiole, BSN, RN, WOCN
     Objective(s): Effectively identifying malnutrition is the first step in implementing supportive nutritional interventions. Holistic wound care should include assessing the nutritional status and requirements of patients. Aims of the study were to: 1) validate the Nutrition Screening Tool for Wound Care (NSTWC) developed by, and for use in, the outpatient wound center at Akron General Medical Center (AGMC); 2) establish inter-rater reliability; and 3) determine if the NSTWC is a better indicator of nutritional status in patients with wounds than the tool currently in use.

     Method(s): A convenience sample of 21 patients was selected for this outpatient, prospective, comparative study. Nurses and dieticians completed the screening tool on the same patient and results were compared to determine inter-rater reliability. To determine nutritional status, markers used to screen for malnutrition, including physical assessment, body mass index, basal energy expenditure, unintentional weight loss, and laboratory data (albumin, pre-albumin, and c-reactive protein), were collected. Patients were rated as low, moderate, or high risk for nutritional deficiency based on the results of each screening tool and malnutrition markers, independently.

     Result(s): There was a high correlation (r = 0.89) between nurse and dietician raters. The level of agreement between the NSTWC and the malnutrition assessment (kappa = 0.72) was significantly higher than the level of agreement between the malnutrition assessment and the tool currently in use in the outpatient wound center (kappa = 0.162). The NSTWC had a sensitivity for detecting malnutrition of 92.9% and a specificity of 100%. The positive predictive value was 1.0 and the negative predictive value was 0.87.

     Conclusion(s): Results from this study suggest that the NSTWC is a valid and reliable indicator of risk for nutritional deficiency in patients who present to the wound center at AGMC and that it is a better indicator of nutritional status in a population with an active wound than the tool currently in use.

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