Vickie R. Driver, MS, DPM, FACFAS Gary Gibbons, MD Geoffrey C. Gurtner, MD, FACS Presenters Vickie R. Driver, MS, DPM, FACFAS Professor of Orthopedic Surgery (clinical) Brown University School of Medicine Chief, Podiatric Surgery Providence VA Medical Center Director, Clinical Research HBO and Wound Healing Center Rhode Island Hospital Providence, Rhode Island Gary Gibbons, MD Medical Director South Shore Hospital Center for Wound Healing Professor of Surgery Boston University School of Medicine Weymouth, Massachusetts Geoffrey C. Gurtner, MD, FACS Johnson and Johnson Professor of Surgery Professor (by courtesy) of Materials Science and Engineering Associate Chairman of Surgery for Research Stanford University School of Medicine Stanford, California
Faculty Disclosures Dr. Driver: Grant/Research Support GSK, KCI, Organogenesis, VLifeSciences; Scientific Advisor Integra, MacroCure, MiMedix; Principal Investigator Celleration Inc. (RCT) Dr. Gibbons and Dr. Gurtner have disclosed no relevant financial relationships with any commercial interest. This continuing education activity includes medication brand names for participant clarity purposes only. No product promotion or recommendations should be inferred. Learning Objectives After completing this activity, participants should be able to Describe how noncontact low-frequency ultrasound (NLFU) stimulates the tissue microenvironment to accelerate healing. Compare and contrasts the IN-BALANCE VLU RCT data to other similar studies Integrate the IN-BALANCE VLU RCT study design and results into clinical practice.
Why Study VLUs? Compression, even when adequate, may not be enough to heal chronic VLUs when there is a dysfunctional microenvironment that needs to be addressed More research needed for therapies that address the microenvironment Limited RCT evidence on VLUs A PubMed search revealed 422 VLU trials in the last 16 years Only 39 were RCTs (placebo/soc) with healing endpoints Of these, 17 demonstrated statistical significance Only 3 of which were on products approved/cleared in the United States VLUs = venous leg ulcers; RCT = randomized controlled trial; SOC = standard of care. Moor, et al. Wound Repair and Regeneration. 2009;17:832-839. Understanding Ultrasound
NLFU Clinical Evidence Quality of Evidence Studies Number of Patients Level lb 1 Meta Analysis 444 Level lb 6 RCTs 335 Level ll 6 Peer Reviewed Studies 390 Meta-Analysis 79.7% volume reduction 12 weeks 85.2% area reduction 7 weeks 41.7% healed at 12 weeks vs 24% with SOC 79% pain reduction Level lll Level IV 4 Peer Reviewed Studies 100+ Case Series & Reports 180 >800 IN BALANCE VLU RCT What Is Ultrasound? What is ultrasound? It is a vibration, a mechanical wave, a cyclic pressure wave with a frequency greater than the upper limit of human hearing (20kHz) What is a pressure wave? It is a repeating pattern of high and low pressure areas moving through a medium (air, water, or mist) causing the molecules of the medium to vibrate Unger P. Ostomy Wound Manage. 2008;54(1):57-60.
Cavitation Shear stress RTKs (e.g., Flk-1) Shc ERK Grb2 Sos Ras JNK Focal Grb2 Sos adhesion site Shc Integrins (e.g., αvβ3) Membrane EC Nucleus AP 1 e.g., MCP 1 TRE Cytoplasm Cavitation Formation & growth of gas bubbles by accumulation of dissolved gas in the fluid The cavity acts to enhance the acoustic streaming process MIST creates a stable cavitation due to its low pressure Acoustical Streaming Extracellular matrix Dijkmas PA, et al. Eur J Echocardiogr. 2004;5(4):243-256. Noncontact Low-Frequency Ultrasound Low-frequency (40 khz), low intensity ultrasound Nonthermal Delivered through saline mist (medium) Noncontact Painless FDA cleared to promote healing US Food and Drug Administration, Center for Devices and Radiological Health. Celleration MIST Therapy 5.1 K140782 clearance letter, May 17, 2005.
Why Study Mechanism of Action? Subset of patients that do not heal even with good SOC Once the underlying cause is addressed, patients have multiple comorbid conditions that interfere with healing that must also be addressed Multiple studies point to a dysfunctional microenvironment that needs to be addressed More research needed for therapies that address the microenvironment of the wound MIST vs Thermal Ultrasound (41 C WHO Safety Limit*) 35 Temperature Rise in Tissue with Ultrasound Traditional @ 3 MHz vs MIST Therapy @ 40 khz Temperature (C) 32 29 26 23 Traditional US @ 3 MHz MIST Therapy @ 40 khz 20 0 2 4 6 Time (min) 8 10 WHO = world health organization. Dyson M. Physiotherapy. 1987;73:116-120.
Pilot RCT Mechanism Study Evaluate the effect of different dose regimens of NLFU therapy in patients with nonhealing diabetic foot ulcers Evaluate effects of NLFU treatment on the components of the wound healing process Inflammation Bacterial load Angiogenesis Collagen formation Yao M, et al. Int Wound J. 2014;11(6):586-593. Methods All 12 randomized subjects received standard wound care 3 times per week for a total of 4 weeks, including a one week run in period For each visit, wound fluid, tissue samples were collected from index wound for: Biochemical analysis (cytokines/growth factors/proteinase) Histological exams Bacterial load Primary Endpoints: Change in wound area over time Change in cytokine, proteinase and growth factor production Changes in wound bacterial load Yao M, et al. Int Wound J. 2014;11(6):586-593.
Wound Healing with NLFU 120 Change in Wound Area with NLFU Therapy Wound Area Reduction (%) 100 80 60 40 20 NLFU 3x/week Control * * * 0 0 1 2 3 *P <.05 vs Control. NLFU = noncontact low-frequency ultrasound. Yao M, et al. Int Wound J. 2014;11(6):586-593. Week 4 5 Results Pilot DFU RCT 600 Effects of NLFU on Change in Cytokine / Proteinase / Growth Factors Percent from Baseline (%) 500 400 300 200 100 Control NLFU 3x/week P >.05 0 Baseline MMP-9 IL-6 IL-8 IL-1b Week 1 Week 4 TNF-1-a GM-CSF Yao M, et al. Int Wound J. 2014;11(6):586-593.
Results Pilot DFU RCT Percent from Baseline (%) 1200 1000 800 600 400 200 NLFU Effect on VEGF NLFU 3x/week Control 0 1 2 Week 3 4 Yao M, et al. Int Wound J. 2014;11(6):586-593. Investigation into Angiogenesis Mechanism Understand the angiogenic cellular pathways impacted by NLFU Humanized excisional wound model with diabetic mice exposed to NLFU 3x/week Mann ZN, et al. Plast Reconstr Surg. 2014;134(3):402-411.
Results Original Wound Remaining (%) 100 80 60 40 * * 20 NLFU Control * 0 0 2 5 7 9 11 15 17 19 22 25 Days to Complete Wound Healing *P <.05. Mann ZN, et al. Plast Reconstr Surg. 2014;134(3):402-411. * * Days to Complete Wound Healing 30 25 20 15 10 5 0 17.3 NLFU * 24.0 Control NLFU Increases SDF-1 SDF-1* Stromal cellderived factor 1 is involved in angiogenesis cell signaling Relative mrna Immunofluorescence (%) 120 100 80 60 40 20 0 25 20 15 10 5 0 * NLFU Control * * Day 7 Day 14 ng/ml 5 4.5 4 3.5 3 2.5 2 * Day 7 Day 14 * NLFU Control Consistent statistically significant results with transcription and protein expression *P <.05. SDF-1 = stromal cell-derived factor 1. Mann ZN, et al. Plast Reconstr Surg. 2014;134(3):402-411.
NLFU Increases VEGF and CD31 VEGF* Vascular endothelial growth factor initiates angiogenesis and mediates blood vessel growth Relative Expression 140 120 100 80 60 40 20 0 NLFU Control CD-31* Marker used to confirm endothelial cells found on the inner lining of blood vessels Relative Expression 140 120 100 80 60 40 20 0 NLFU Control NLFU improved neovascularization and wound closure rates due to stimulated release of angiogenic factors *P <.05. VEGF = vascular endothelial growth factor; CD-31 = platelet endothelial cell adhesion molecule-1. Mann ZN, et al. Plast Reconstr Surg. 2014;134(3):402-411. NLFU Reduces Bioburden Staphylococcus aureus Sham Control MIST Therapy Mechanical stress caused by the ultrasound energy of MIST has detrimental effects on ridged bacterial cells Staph aureus Pseudomonas aeruginosa Pseudomonas aeruginosa MRSA VRE Methicillinresistant Staphylococcus aureus Acinetobacter E. coli Kavros SJ, et al. J Am Podiatr Med Assoc. 2007;97(2):95-101. Serena, et al. Ostomy Wound Manage. 2009;55(1)22-30.
Investigation into Biofilm Mechanism Understand the NLFU effect on P aeruginosa biofilm Published rabbit ear model with NLFU administered every day or every other day for 6 days Seth AK, et al. Wound Repair Regen. 2013;21(2):266-274. NLFU Disrupts Biofilm Biofilm P aeruginosa Biofilm Control (untreated) Large amounts of rod-shaped bacteria with interspersed extracellular matrix MIST Therapy (3 treatments) Significantly reduced amount of bacteria and associated matrix, revealing areas of bare wound bed Seth AK, et al. Wound Repair Regen. 2013;21(2):266-274.
MIST Disrupts Biofilm Healing Progression Measured by Epithelial Gap Epithelial Gap (mm) 6 5 4 P <.001 3 A clear clinical indicator that biofilm has been disrupted is healing progression 2 0 6 12 Healing Progression (days) Untreated (A) MIST (B) (A) TGA (B) TGA EG EG TGA TGA NLFU effectively decreases the viable bacterial burden of P aeruginosa infected biofilm wounds significantly improving healing and decreased host inflammatory response TGA = total granulation area; EG = epithelial gap. Seth AK, et al. Wound Repair Regen. 2013;21(2):266-274. Summary of Mechanism Results Pro-inflammatory cytokines, IL-6, IL-8, IL-1b, TNF-alpha, showed reduction in response to NLFU thus decreasing host inflammatory response Bacterial load was significantly reduced with NLFU NLFU disrupts wound biofilm NLFU stimulated release of multiple angiogenic factors, improving neovascularization Increase in collagen deposition and dermal thickness suggests that NLFU improves the integrity of healed diabetic wounds in contrast to the typically fragile reepithelialization in diabetic healing prone to breakdown IL = interleukin.
Correct functioning of the venous system depends on a complex series of pumps and valves that are individually frail and prone to malfunction. Venous Drainage of Lower Limb Representation of superficial and deep venous drainage 1. Sapheno-femoral junction 2. Deep vein (femoral) 3. Deep fascia 4. Superficial vein (great saphenous vein) 5. Calf muscle pump 6. Perforating veins 7. Sapheno-popliteal junction 8. Short saphenous vein O Donnell TF Jr, et al. J Vasc Surg. 2014;60:3s-59s. Venous Pathology Develops when venous return is impaired for any reason: can be deep, superficial, or mixed, leading to peripheral venous reflux or insufficiency Can result from primary muscle pump failure, from venous obstruction (thrombotic or nonthrombotic), or from venous valvular incompetence, which may be segmental or involve whole leg Skin damage: red and white blood cells stick to walls and migrate out of the blood vessels into the tissues Red blood cells break down leaving iron deposited in the tissues and a brown discoloration Activated white blood cellss enter tissues, release chemicals, and damage tissues leading to self-digestion of the tissues or build up of products within the tissues (eg, fibrin), and in turn, impede diffusion of oxygen and other nutrients Result can be death of the tissues surrounding the veins leading to a venous ulcer (sometimes called stasis ulcers or venous stasis ulcers) O Donnell TF Jr, et al. J Vasc Surg. 2014;60:3s-59s.
Why Study VLUs? Diabetic foot ulcer effect already demonstrated in RCT and meta-analysis Limited RCT evidence on VLUs even less that show significance (422 studies, 39 RCTs, and 17 showed significance 3 on devices commercially approved in US) VLUs tend to be recurrent (>60% within 1 year) big morbidity and cost issue Compression (even when adequate) may not be enough to heal chronic VLUs when there is a dysfunctional microenvironment that needs to be addressed Preclinical research demonstrated that a microenvironment exists and MIST therapy can jump-start healing Study Design Evidence Based Treatment Must Address the Downstream Effects of the Disturbed Venous Anatomy and Physiology = The Hostile Wound and it s Microenvironment Moor AN, et al. Wound Repair Regen. 2009;17(6):832-839. Gibbons GW, et al. Ostomy Wound Manage. 2015;61(1):16-29. Addressing the Hostile Wound Environment: Uncontrolled, Sustained Inflammation Noncycling (senescent) CELLS Impaired Decreased response to migration and signaling proliferation molecules MATRIX Impaired ECM production and maintenance Deficiency of TIMPs creates MMP imbalance REMOVES: Devitalized tissue, bone, bacteria proteolytic enzymes, senescent cells Dependently drains pus Changes chronic wound to acute CHEMICALS Abnormal levels/ imbalance of cytokines and growth factors EGF, FGF-2, TGF-B, PDGF, VEGF IL-1, IL-2, TGF-a INFECTION Biofilm PRESSURE ISCHEMIA VENOUS EDEMA ECM = extracellular matrix; TIMPs = tissue inhibitors of metalloproteinases; MMP = matrix metalloproteinase; EGF = epidermal growth factor; FGF = fibroblast growth factor; TGF = transforming growth factor; PDGF = platelet-derived growth factor; VEGF = vascular endothelial growth factor.
Study Design Main Points Prospective RCT, 22 centers 112 subjects eligible, 81 randomized and treated Treatment arms: MIST + SOC 3x/week vs SOC 1x/week (min) Run-in period to ensure wound was stalled 4 weeks is a published surrogate of healing Endpoint was objective and adjudicated (eliminated the bias of measurer and limitation of no sham) SOC was based on guidelines of 3 societies Compression was gold standard (30-40 mm Hg) Frequency was based on survey of 30+ wound centers Investigators could bring SOC in up to 3 x per week DSMB oversaw the data management Monitoring was third-party Population homogenious (adjudicated as venous etiology) DSMB = data safety management board. IN BALANCE VLU Protocol Required SOC All subjects Excisional or sharp debridement at enrollment Sharp debridement as needed at each visit Dressings to promote a moist wound healing environment Compression wrap 30 to 40 mm Hg (Profore 4-layer provided) Minimum of dressing change and compression application once per week (and up to 3 times per week per investigator discretion)
Associated Comorbidities Mean ± SD (N), Median [Interquartile Range], Range or % (n/n) Characteristic SOC NLFU+SOC NLFU = noncontact, low-frequency ultrasound. P value SOC vs NLFU+SC BMI 40 27.5 (11/40) 36.6 (15/41).4769 Coronary Artery Disease 10.0 (4/40) 4.9 (2/41).4321 Diabetes 27.5 (11/40) 41.5 (17/41).2441 Hypertension 65.0 (26/40) 68.3 (28/41).8161 Anemia 7.5 (3/40) 19.5 (8/41).1935 Prior ulcers 85.0 (34/40) 78.0 (32/41).569 Edema (moderate or severe) 40.0 (16/40) 53.7 (22/41).2681 Ankle brachial index 0.9 2.5 (1/40) 9.8 (4/41).3593 # subjects and # comorbidities.5858 4 comorbidities 20.0 (8/40) 29.3 (12/41) 5 comorbidities 7.5 (3/40) 9.8 (4/41) 6 comorbidities 0 4.9 (2/41) 7 comorbidities 0 2.4 (1/41) % subjects with 4 or more associated comorbidities 27.5 (11/40) 46.3 (19/41).1078 Demographics/Ulcer Characteristics Mean ± SD (N), Median [Interquartile Range], Range or % (n/n) P value Characteristic SOC (N=40) NLFU+SOC (N=41) SOC vs NLFU+SC Median age (years) 60.0 [52.0, 67.5] 58.0 [51.0, 68.0].9211 Male 72.5% (29/40) 68.3% (28/41).8086 Median BMI (kg/m 2 ) 33.2 [28.2, 42.2] 37.4 [29.3, 45.2] (.4414) Recurrent ulcer (%) 60.0% (24/40) 51.2% (21/41).5768 Median ulcer size at randomization (cm 2 ) Median ulcer age at randomization (months) 9.8 [4.6, 16.8] 2.5-36.9 8.9 [3.6, 29.3] 1.7-204.5 12.4 [6.5, 19.2] 3.1-53.3 10.3 [3.9, 24.1] 1.5-114.0 (.1470).5332 (.8464) BMI = body mass index.
Primary Endpoint Wound Size Reduction (%) Mean Percent Wound Area Reduction (cm at 4 weeks; P =.02) 70 61.6 60 50 45 40 30 20 10 0 NLFU + SOC (n=41) SOC (n=40) Significance continues after adjusting for wound size and wound area Median and absolute area reductions were also statistically significant Secondary Objective Weekly Reduction 12 Weekly Mean Absolute Reduction in Wound Area (cm 2 ) Ulcer Area Reduction (cm 2 ) 10 8 6 4 2 NLFU + SOC SOC 0 1* 2* 3* 4* 5* 6* 7 9 11* Weeks Post Randomization *Statistically significant differences demonstrated.
Secondary Endpoint Pain Levels 3.5 3.0 Median VAS Pain Score Reduction (P =.01) NLFU + SOC (n=41) SOC (n=40) Pain Score 2.5 2.0 1.5 1.0 0.5 0 Randomization 4 Weeks Post-Randomization Significant differences noted in the reduction in pain scores (VAS 0-10 scale) from randomization to 4 weeks post-treatment NLFU+SOC subjects reported an 80% reduction where SOC group reported a 20% reduction VAS = visual analog scale. Wound Closure 41% of subjects experienced wound closure during the trial NFLU+SOC had twice the number of closures by 7 weeks post-randomization In total, 23 subjects that received NLFU during the trial healed compared to 10 SOC alone subjects
Other VLU Studies VLU Trial with High-Frequency and NLFU Ultrasound 90 outpatients (47 men, 43 women, average age = 38.3 years old) N=30 SOC alone N=30 SOC plus high frequency ultrasound N=30 SOC plus noncontact, low-frequency ultrasound Treated 3 times a week for 3 months Assessed at baseline, 2 months and 4 months End points included wound area reduction, edema and pain Results A statistically significant difference (P=.04) was noted in all three groups combined from baseline and 4 months Differences in the amount of edema and pain rating scores were also significant at the 4-month, follow-up visit (P<.05) Ulcer area reductions were 5.32 cm² (55.4%) for SOC, 6.6 cm² (66.9%) for high frequency ultrasound, and 7.29 cm² (72.9%) for NLFU Olyaie M, et al. Ostomy Wound Manage. 2013;59(8):14-20.
Venous Leg Ulcer Trial with Cell Based Therapy Biologic cell-based therapy Human fibroblast-derived dermal substitute 182 participants Primary endpoint was 12 heal rate 34% in treatment group and 31% in SOC group No statistically significant differences Harding K, et al. Int Wound J. 2013;10(2): 132-137. Venous Leg Ulcer Trial with Polymer Wound Membrane 4 arm RCT evaluated the safety, efficacy and dosing of polymer wound healing technology Every other week applications for the 20-week study Endpoint was measured at 5 months 82 VLU participants Ulcer duration 3.6 months 86% of the VLUs healed in the treatment arm Kelechi TJ, et al. J Am Acad Dermatol. 2012;66(6):e209-e215.
Case Examples and Clinical Application of the Evidence Primary Venous NLFU Subject Enrollment Randomization 18.1 cm 2 11.5 cm 2 4 Weeks Post-Randomization 7 Weeks Post-Randomization 0.2 cm 2 0 cm 2
Primary Venous NLFU Subject Enrollment Randomization 18.6 cm 2 12.4 cm 2 4 Weeks Post-Randomization 9 Weeks Post-Randomization 5.2 cm 2 0 cm 2 Primary Venous SOC Subject (Crossed to NLFU) Still Open Enrollment Randomization 4.7 cm 2 3.8 cm 2 4 Weeks Post-Randomization 11 Weeks Post-Randomization 2.2 cm 2 0.1 cm 2
Mixed Venous NLFU Subject Enrollment Randomization 6.9 cm 2 5.2 cm 2 4 Weeks Post-Randomization 11 Weeks Post-Randomization 2.5 cm 2 1.5 cm 2 Mixed Venous SOC Subject (Crossed to NLFU) Enrollment Randomization 13.2 cm 2 11.0 cm 2 4 Weeks Post-Randomization 10 Weeks Post-Randomization 8.7 cm 2 0 cm 2
Mixed Venous NLFU Subject Enrollment Randomization 23.2 cm 2 20.5 cm 2 4 Weeks Post-Randomization 11 Weeks Post-Randomization 2.6 cm 2 0.8 cm 2 IN BALANCE VLU Study Strengths Eligible cohort was homogenous (stalled venous ulcer) Adjudicated by blinded experts as having venous disease Run-in period to force standardization of treatment Nonstalled/undertreated wounds (those that reduced >30% in run-in) were exited Objective endpoint (digital image) with blinded adjudication DSMB oversight and 100% monitoring of subjects (third-party) Compliance during the trial was extremely high <1% missed visits and <3% out of window visits >98% compliance with 30 to 40 mm Hg compression All subjects met the minimum number of NLFU treatments
IN BALANCE VLU Study Limitations Investigators and subjects were not blinded May have impacted quality-of-life outcomes Mitigated bias of primary endpoint through blinded adjudicator of digital images Treatment frequency varied Minimum of 1 x per week SOC; NLFU 3 x per week Mitigated by allowing investigators to treat SOC subjects up to 3 times per week Summary of Findings The VLU population is far more complicated than previously reported VLU subjects are increasingly younger with high degree of comorbidity Even with effective diagnosis and appropriate SOC, a portion of VLUs will not heal, particularly in wounds with a dysfunctional microenvironment NLFU in addition to SOC is superior to SOC alone in wound area reduction after 4 weeks of treatment This treatment remained effective regardless of wound size and age
Additional Findings In subjects that were adequately compressed (30-40 mm Hg) prior to enrollment in the study, the healing rate difference at 4 weeks was highly significant at P=0.0005, suggesting that MIST therapy will facilitate VLU healing where guideline-defined SOC has failed There were a high number of comorbidities in this study population, further demonstrating MIST is effective in catalyzing stalled wounds in highly complex patients with multiple factors stacked against healing The study showed that the larger and older the ulcer, the less likely SOC treatment alone was able to achieve healing, whereas MIST healed regardless of ulcer size or age SOC patients that crossed over and received MIST Therapy treatments 3 times per week ALL healed within 7 weeks of crossing over What We Learned! Diagnosing VLU 20% of subjects enrolled as venous by the sites were adjudicated as nonvenous etiology Pure venous ulcers are rare Only 17% of the subjects were primary venous Guidelines for SOC are not being followed 35% were not debrided in the 12 months prior to enrollment Only 60% were adequately compressed in the 30 days prior to enrollment 27 failed randomization criteria (reduced >30% in run-in) Advanced modalities had been utilized in 48% of the subjects
Clinical Applications Older patients and those with multiple comorbid conditions Older wounds of any type and in any area: Not necessarily size differential as small wounds can be problematic Wounds not responding to evidence-based SOC Wounds needing help transitioning to the proliferative stage following early aggressive surgical debridement Likelihood of biofilm presence Highly contaminated wounds Wounds associated with some type of ischemia Clinical Applications Wounds with any of the following characteristics following debridement An indurated or edematous wound margin Does it An inflamed (reddened) wound margin need biopsy? A dull red/pink wound bed The presence of a grey or cloudy film over the wound bed Red, irritated, and sloughing epidermal tissue Wound bed preparation for acceleration of primary healing or reconstructive surgery including skin grafts or regenerative cellular tissue products
Key Factors Leading to Failure to Heal Underlying pathophysiology Venous and/or arterial insufficiency Infection/microbial imbalance Sustained inflammation Pressure or recurrent injury Diabetes/associated disorders/systemic disease/comorbid conditions Immunosuppression/impaired host Edema Nutritional deficits Concomitant medications Aging Smoking Abnormal wound microenvironment Pain Compliance: Adherence to prescription plan Iatrogenic: Little wound healing guided by evidence Krasner D, Kane DP, eds. Chronic Wound Care: A Clinical Source Book for Healthcare Professionals. 2nd ed. Wayne, PA: Health Management Publications Inc; 1997:1-4. Falanga V, ed. Cutaneous Wound Healing. London, United Kingdom: Martin Dunitz; 2001. Photo courtesy of Gary W. Gibbons, MD. Systemic Support: Treating Underlying Conditions Remember: it is a patient with a wound Address underlying pathology Revascularize patients with peripheral arterial disease Evaluate and prescribe venous disease For combined: prescribe arterial first then venous Protect high risk areas Control peripheral edema Correct systemic factors interfering with wound healing Ensure adequate nutrition Normalize blood glucose Encourage smoking cessation Adjust necessary systemic medication to promote wound healing Physical and emotional therapy Treat comorbid conditions 30-35 cal/kg/day, 1.5 g protein/kg/day, vitamin C, multivitamin, trace minerals BS optimal control Bryant RA, Nix DP, eds. Acute & Chronic Wounds: Current Management Concepts. 4th ed. St. Louis, MI: Mosby, Inc.; 2011:308-310.
Conservative Therapy for Venous Disease Compression is essential for prevention and recidivism Reduces the stress/diameter of the veins, increases flow velocity, restoring venous hemodynamics, especially improving calf muscle pump functioning, decreasing the chance of thrombosis; activates fibrinolytic activity in the blood Reduces filtration of fluid out of the intravascular space and improves lymphatic flow, thereby reducing edema Graduated compression reduces reflux and improves venous outflow, thus decreasing venous pressure at rest and with ambulation Anti-inflammatory, yielding improvement in pain and swelling Three main types of compression elastic compression stockings or bandages inelastic compression garments or bandages pneumatic compression pumps Skin health and maintenance Moisturizers and anti-inflammatory creams Addressing the Hostile Wound Environment: Uncontrolled, Sustained Inflammation Noncycling (senescent) CELLS Impaired Decreased response to migration and signaling proliferation molecules MATRIX Impaired ECM production and maintenance Deficiency of TIMPs creates MMP imbalance CHEMICALS Abnormal levels/ imbalance of cytokines and growth factors EGF, FGF-2, TGF-B, PDGF, VEGF IL-1, IL-2, TGF-a INFECTION Biofilm PRESSURE ISCHEMIA VENOUS EDEMA ECM = extracellular matrix; TIMPs = tissue inhibitors of metalloproteinases; MMP = matrix metalloproteinase; EGF = epidermal growth factor; FGF = fibroblast growth factor; TGF = transforming growth factor; PDGF = platelet-derived growth factor; VEGF = vascular endothelial growth factor.
Conclusions Early diagnosis and appropriate intervention is paramount to reducing wound care costs and improving healing rates and quality of life Subjects who have reduced <30% after two weeks of optimal standard of care treatment should have interventions that address the ulcer at a microenvironmental level, such as NLFU, should be introduced NLFU demonstrates remarkable consistency of reduction in wound area, volume, pain Improvements were accompanied by favorable rates of healed chronic wounds as early as 6 and 12 weeks Q&A