Systematic review of economic evaluations of human cell-derived wound care products for the treatment of venous leg and diabetic foot ulcers

Contemporary treatment strategies for Type 2 diabetes-related macrovascular disease

Type 2 diabetes mellitus poses a major challenge to healthcare providers in the coming years as its prevalence increases across the globe. The disease doubles the risk of cardiovascular morbidity and mortality, with 70% of sufferers dying from a cardiac cause. Large clinical trials of current glucose-lowering therapies for Type 2 diabetes have shown no benefit in reducing the risk of macrovascular events. Blood pressure control, angiotensin-converting enzyme inhibitor therapy and improvement of dyslipidemia with statins have proven benefit in reducing cardiovascular risk in Type 2 diabetes. A growing understanding of the importance of pathological processes including endothelial dysfunction, abnormal growth factor biology, oxidative stress, dysregulation of adipokines and deficient vascular repair and regeneration in insulin-resistant states promises new treatments to combat the problem.

Skin substitutes: an overview of the key players in wound management

In a relatively short timespan, a wealth of new skin substitutes made of synthetic and biologically derived materials have arisen for the purpose of wound healing of various etiologies. This review article focuses on providing an overview of skin substitutes including their indications, contraindications, benefits, and limitations. The result of this overview was an appreciation of the vast array of options available for clinicians, many of which did not exist a short time ago. Yet, despite the rapid expansion this field has undergone, no ideal skin substitute is currently available. More research in the field of skin substitutes and wound healing is required not only for the development of new products made of increasingly complex biomolecular material, but also to compare the existing skin substitutes.

Efficacy of topical recombinant human platelet-derived growth factor for treatment of diabetic lower-extremity ulcers: Systematic review and meta-analysis

OBJECTIVE

Recombinant human platelet-derived growth factor (rhPDGF) is used topically in the treatment of diabetic lower-extremity ulcers. There have been few meta-analyses of the efficacy of rhPDGF in this treatment context. The aim of this study was to perform an updated systematic review and meta-analysis to assess the clinical efficacy of rhPDGF in the treatment of diabetic lower-extremity ulcers.

METHODS

We searched the MEDLINE, Cochrane Library, EMBASE and Web of Knowledge databases up to April 30, 2014. Studies were identified and selected, and data were extracted by two independent reviewers. The primary efficacy outcome was complete healing rate. Adverse events were also assessed. The studies were evaluated for quality and publication bias.

RESULTS

A total of 6 randomized controlled trials including 992 patients were selected from 173 identified studies. The studies compared rhPDGF treatment in the context of standard of care (SOC) to placebo or SOC alone. In the absence of study heterogeneity, a fixed-effects model was performed, and the combined odds ratio (OR) indicated a significantly greater complete healing rate in patients treated with rhPDGF compared to placebo or SOC alone. The ORs ranged from 0.58 to 2.77, with a combined OR of 1.53 (95% CI = 1.14 to 2.04, p = 0.004). A sensitivity analysis (leave-one-out method) indicated good study reliability, and a funnel plot with Egger test showed no publication bias.

CONCLUSION

These results indicate that rhPDGF is efficacious in the treatment of diabetic lower-extremity ulcers.

Diabetic foot ulcers: evaluation and management

Diabetic foot ulcers (DFUs) are a common complication of diabetes and present a significant health risk to patients, as well as impose a large economic burden. Evaluation for contributory factors that may impact general health or healing, such as hyperglycemia, peripheral artery disease, neuropathy, and nutritional status, is of the utmost importance. Management of DFUs requires involvement of a multidisciplinary team and a standardized approach to patient care. Standard therapy for DFUs includes offloading and debridement. Assessment and control of infection are critical, including determining the severity of the infection, which may drive therapeutic approaches. For recalcitrant ulcers, adjuvant therapies are used to hasten the healing process, and newer therapies are under investigation.

Economic evaluations of guideline-based or strategic interventions for the prevention or treatment of chronic wounds

BACKGROUND

Costs of chronic wound care are significant, but systematic reviews of cost-effectiveness studies regarding guideline-based or strategic interventions are scarce.

OBJECTIVES

Our objectives were to assess/compare the cost effectiveness of new interventions/systems designed to improve the prevention/treatment of chronic wounds in adult populations against current care and provide decision makers with information on which to base future interventions for chronic wound management.

DATA SOURCES

Data sources included PubMed, Scopus, HTA, and NHS EED.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, AND INTERVENTIONS

We included comparative health economic evaluations of interventions published in English designed to prevent or treat adult chronic wounds that were guideline-based or strategic in nature and from which an incremental cost-effectiveness ratio or incremental net health benefit was reported or could be calculated.

STUDY APPRAISAL AND SYNTHESIS METHODS

Study and model characteristics and outcomes were extracted into pre-designed tables. Quality assessment of studies was based on literature-reported methods. Studies were assigned strength of evidence ratings and recommendation level for decision makers.

RESULTS

A total of 16 health economic evaluations were included, of which ten were trial based and six were wholly model based. Only three studies had high, and five studies moderate, strength of evidence and were recommended for decision makers. All studies had some shortcomings regarding time horizon, costs, effectiveness units, and methodological reporting. Two studies had major flaws.

LIMITATIONS

Limitations include missed studies published in non-English languages or not cited in searched databases; judgment bias in assessing studies.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Few well conducted cost-effectiveness studies exist to guide decision makers regarding guideline-based or strategic interventions for chronic wounds.

Venous ulcer care: which dressings are cost effective?

Healed or open venous ulcers may be present in up to 1% of Western populations and consume a large amount of healthcare resources. These ulcers are characterized by a chronic inflammatory environment with impaired healing and often require months for closure. The average monthly cost of care for an open ulcer has been estimated to be $4095. The fundamental tenets of ulcer care include adequate compression and maintaining a moist wound environment with an appropriate primary dressing. A number of specialized products including semi-occlusive/occlusive, antimicrobial, and advanced wound matrix dressings are now available. However, there is little data from appropriate clinical studies to suggest significantly improved outcomes with any of these dressings. Data regarding their cost-effectiveness is also limited, often conflicting, and subject to bias. At present, there is little solid evidence to guide the choice of primary dressings and a patient-centered approach focusing on characteristics of both the patient and their ulcer, while paying attention to costs, may be most appropriate.

Treating the whole not the hole: necessary coupling of technologies for diabetic foot ulcer treatment

Type 2 diabetes is the epidemic of our generation, and diabetic foot ulcers (DFUs) are a major complication. Although DFU formation itself can indicate disease progression, the failure to effectively treat ulcers contributes further to a decay in patient quality of life and increased mortality. Herein we discuss the development of next-generation DFU therapies including: (i) topical growth factors, (ii) scaffolds, and (iii) cellular therapies. Individually these therapies have yielded measurable but modest improvements in DFU repair. Because DFUs arise as a result of multiple biochemical deficiencies, a singular treatment modality is unlikely to be effective. Next-generation DFU technologies must be combined to address effectively the complex underlying pathology and enable reliable DFU repair.

Macrophage stimulating agent soluble yeast β-1,3/1,6-glucan as a topical treatment of diabetic foot and leg ulcers: A randomized, double blind, placebo-controlled phase II study

AIMS/INTRODUCTION

Dysregulated inflammatory response is believed to be an important factor in the pathogenesis of several late complications of diabetes mellitus. β-Glucans are potent inducers of immune function. The present randomized, double blind, two-center, placebo-controlled study was undertaken to explore safety, tolerability and efficacy of soluble β-1,3/1,6-glucan (SBG) as a local treatment of diabetic foot ulcers.

MATERIALS AND METHODS

A total of 60 patients with type 1 or 2 diabetes and lower extremity ulcers (Wagner grade 1-2, Ankle/Brachial Index ≥0.7) received SBG or a comparator product (methylcellulose) locally three times weekly up to 12 weeks in addition to conventional management scheme. A total of 54 patients completed the study.

RESULTS

A tendency for shorter median time to complete healing in the SBG group was observed (36 vs 63 days, P = 0.130). Weekly percentage reduction in ulcer size was significantly higher in the SBG group than in the methylcellulose group between weeks 1-2, 3-4 and 5-6 (P < 0.05). The proportion of ulcers healed by week 12 was also in favor of SBG (59% vs 37%, P = 0.09), with a significantly higher healing incidence in the SBG group at week 8 (44% vs 17%, P = 0.03). SBG was safe and well tolerated. There was a clinically significant difference regarding the incidence of serious adverse events in favor of the SBG treatment.

CONCLUSIONS

Local treatment of diabetic lower extremity ulcers with β-1,3/1,6-polyglucose shows good safety results. This β-glucan preparation shows promising potential as a treatment accelerating cutaneous healing. Further studies are required to confirm this effect. This trial was registered with ClinicalTrials.gov (no. NCT00288392).

Advanced therapies for chronic wounds: NPWT, engineered skin, growth factors, extracellular matrices

Advanced wound care implies the use of products or procedures that are specialized. Although dermatologists are used to being specialists of the skin, hair, and nails, chronic wound care has evolved such that there are some specific treatment options that are more commonly ordered and performed in wound care clinics. Wound care clinics are staffed by specialists and generalists including dermatologists, but also orthopedic surgeons, vascular surgeons, infectious disease specialists, internists, family practitioners, hyperbaric oxygen-trained physicians from a variety of backgrounds, podiatrists, physician assistants, and nurse practitioners. The care of chronic wounds has almost become its own specialty, with so-called advanced therapies now including the use of growth factors, extracellular matrices, engineered skin, and negative pressure wound therapy. It is critical that the dermatologists understand the treatments such that they can appropriately apply or order them directly, or be involved with the care of their patients receiving these therapies.

Clinical and economic assessment of diabetic foot ulcer debridement with collagenase: results of a randomized controlled study

BACKGROUND

Despite significant advances, the treatment of diabetic foot ulcers (DFUs) remains a major therapeutic challenge for clinicians, surgeons, and other health care professionals. There is an urgent need for new strategies with clinically effective interventions to treat DFUs to reduce the burden of care in an efficient and cost-effective way.

OBJECTIVE

This randomized trial evaluated and compared the clinical effectiveness, tolerability, and costs of clostridial collagenase ointment (CCO) debridement to that of debridement using saline moistened gauze (SMG) and selective sharp debridement for the treatment of DFUs.

METHODS

Randomized, controlled, parallel group, multicenter, open-label, 12-week study of 48 patients with neuropathic DFUs randomized to 4 weeks of treatment with either CCO or SMG after baseline surgical debridement. The primary end point was the condition of the ulcer bed at the end of treatment as measured using a standardized wound assessment tool. Secondary end points were the percentage of reduction in wound area and therapeutic response rates. Adverse events were monitored for the tolerability analysis. In addition, a comparative cost-effectiveness analysis was performed from the perspective of the Centers for Medicare and Medicaid Services as a payer.

RESULTS

Both the CCO and SMG groups had significantly improved wound assessment scores after 4 weeks of treatment (CCO, -2.5, P = 0.007; SMG, -3.4, P = 0.006). Only CCO treatment resulted in a statistically significant decrease from baseline in the mean wound area at the end of treatment (P = 0.0164) and at the end of follow-up (P = 0.012). In addition, the CCO group exhibited a significantly better response rate at the end of follow-up compared with the SMG group (0.92 vs 0.75, P < 0.05). Reported adverse events were similar between the 2 treatment groups. None of the reported adverse events were considered to be related to treatment. The economic analysis indicated that the direct mean costs per responder in the physician office setting of care were $832 versus $1042 for the CCO group versus the SMG group, whereas the direct mean costs per responder in the hospital outpatient department setting were $1607 versus $1980.

CONCLUSIONS

CCO treatment provides equivalent debridement of DFUs similar to SMG while fostering better progress toward healing as measured by decreasing wound area over time and improved response rates at the end of follow-up. In addition, CCO yields a more favorable cost-effectiveness ratio in both the physician office and hospital outpatient department settings of care. ClinicalTrials.gov identifier: NCT01056198.

The regenerative potential of fibroblasts in a new diabetes-induced delayed humanised wound healing model

Cutaneous diabetic wounds greatly affect the quality of life of patients, causing a substantial economic impact on the healthcare system. The limited clinical success of conventional treatments is mainly attributed to the lack of knowledge of the pathogenic mechanisms related to chronic ulceration. Therefore, management of diabetic ulcers remains a challenging clinical issue. Within this context, reliable animal models that recapitulate situations of impaired wound healing have become essential. In this study, we established a new in vivo humanised model of delayed wound healing in a diabetic context that reproduces the main features of the human disease. Diabetes was induced by multiple low doses of streptozotocin in bioengineered human-skin-engrafted immunodeficient mice. The significant delay in wound closure exhibited in diabetic wounds was mainly attributed to alterations in the granulation tissue formation and resolution, involving defects in wound bed maturation, vascularisation, inflammatory response and collagen deposition. In the new model, a cell-based wound therapy consisting of the application of plasma-derived fibrin dermal scaffolds containing fibroblasts consistently improved the healing response by triggering granulation tissue maturation and further providing a suitable matrix for migrating keratinocytes during wound re-epithelialisation. The present preclinical wound healing model was able to shed light on the biological processes responsible for the improvement achieved, and these findings can be extended for designing new therapeutic approaches with clinical relevance.

Importance of insulin resistance to vascular repair and regeneration

Metabolic insulin resistance is apparent across a spectrum of clinical disorders, including obesity and diabetes, and is characterized by an adverse clustering of cardiovascular risk factors related to abnormal cellular responses to insulin. These disorders are becoming increasingly prevalent and represent a major global public health concern because of their association with significant increases in atherosclerosis-related mortality. Endogenous repair mechanisms are thought to retard the development of vascular disease, and a growing evidence base supports the adverse impact of the insulin-resistant phenotype upon indices of vascular repair. Beyond the impact of systemic metabolic changes, emerging data from murine studies also provide support for abnormal insulin signaling at the level of vascular cells in retarding vascular repair. Interrelated pathophysiological factors, including reduced nitric oxide bioavailability, oxidative stress, altered growth factor activity, and abnormal intracellular signaling, are likely to act in conjunction to impede vascular repair while also driving vascular damage. Understanding of these processes is shaping novel therapeutic paradigms that aim to promote vascular repair and regeneration, either by recruiting endogenous mechanisms or by the administration of cell-based therapies.

A Paradigm of Fibroblast Activation and Dermal Wound Contraction to Guide the Development of Therapies for Chronic Wounds and Pathologic Scars

SIGNIFICANCE

Delayed wound healing and pathologic scarring are abnormal processes that can be thought of as occurring on a wound healing continuum, where insufficient wound contraction leads to nonhealing wounds, and overexuberant wound contraction leads to scarring. Chronic nonhealing wounds, including diabetic foot wounds, decubitus ulcers, and venous stasis ulcers, affect millions of people annually in the United States and costs billions of dollars. Similarly, pathologic scaring affects more than 40 million Americans annually and also costs billions of dollars.

CRITICAL ISSUES

While there are multiple factors that contribute to chronic nonhealing wounds and pathologic scars, a derangement in wound contraction is common to both. In this article, we will present a paradigm of dermal wound contraction, derived from clinical observations and basic science evidence, which pertains to chronic nonhealing wounds and pathologic scars.

RECENT ADVANCES

We will review how select therapies currently under investigation and in development fit the paradigm.

FUTURE DIRECTIONS

The paradigm will facilitate translational research and enable the development of future innovative therapies.

Novel collagen/gelatin scaffold with sustained release of basic fibroblast growth factor: clinical trial for chronic skin ulcers

Chronic skin ulcers such as diabetic ulcers and venous leg ulcers are increasing and are a costly problem in healthcare. We have developed a novel artificial dermis, collagen/gelatin sponge (CGS), which is capable of sustained release of basic fibroblast growth factor (bFGF) for more than 10 days. The objective of this study was to investigate the safety and efficacy of CGS impregnated with bFGF in the treatment of chronic skin ulcers. Patients with chronic skin ulcers that had not healed in at least 4 weeks were treated with CGS impregnated with bFGF at 7 or 14 μg/cm(2) after debridement, and the wound bed improvement was assessed 14 days after application. Wound bed improvement was defined as a granulated and epithelialized area on day 14 with a proportion to the baseline wound area after debridement of 50% or higher. The wound area, the wound area on day 14, and the granulation area on day 14 were independently measured by blinded reviewers in a central review using digital images of wounds taken with a calibrator. Patients were followed up until 28 days after application to observe the adverse reactions related to the application of CGS. From May 2010 to June 2011, 17 patients were enrolled and, in 16 patients, the wound bed improved. Among the randomized patients in step 2, no significant difference was seen between the low-dose group and the high-dose group. No serious adverse reactions were observed. Adverse reactions with a clear causal relationship to the study treatment were mild and patients quickly recovered from them. This study is the first-in-man clinical trial of CGS and showed the safety and efficacy of CGS impregnated with bFGF in the treatment of chronic skin ulcers. This combination therapy could be a promising therapy for chronic skin ulcers.

Cellular events and biomarkers of wound healing

Researchers have identified several of the cellular events associated with wound healing. Platelets, neutrophils, macrophages, and fibroblasts primarily contribute to the process. They release cytokines including interleukins (ILs) and TNF-α, and growth factors, of which platelet-derived growth factor (PDGF) is perhaps the most important. The cytokines and growth factors manipulate the inflammatory phase of healing. Cytokines are chemotactic for white cells and fibroblasts, while the growth factors initiate fibroblast and keratinocyte proliferation. Inflammation is followed by the proliferation of fibroblasts, which lay down the extracellular matrix. Simultaneously, various white cells and other connective tissue cells release both the matrix metalloproteinases (MMPs) and the tissue inhibitors of these metalloproteinases (TIMPs). MMPs remove damaged structural proteins such as collagen, while the fibroblasts lay down fresh extracellular matrix proteins. Fluid collected from acute, healing wounds contains growth factors, and stimulates fibroblast proliferation, but fluid collected from chronic, nonhealing wounds does not. Fibroblasts from chronic wounds do not respond to chronic wound fluid, probably because the fibroblasts of these wounds have lost the receptors that respond to cytokines and growth factors. Nonhealing wounds contain high levels of IL1, IL6, and MMPs, and an abnormally high MMP/TIMP ratio. Clinical examination of wounds inconsistently predicts which wounds will heal when procedures like secondary closure are planned. Surgeons therefore hope that these chemicals can be used as biomarkers of wounds which have impaired ability to heal. There is also evidence that the application of growth factors like PDGF will help the healing of chronic, nonhealing wounds.

An exploratory clinical study on the safety and efficacy of an autologous fibroblast-seeded artificial skin cultured with animal product-free medium in patients with diabetic foot ulcers

Cultured dermal substitutes have been used for the treatment of chronic skin ulcers; however, the biological risks of animal-derived materials in the culture process such as foetal bovine serum (FBS) have been reported. In this study, we prepared an autologous fibroblast-seeded artificial dermis (AFD) using animal-product-free medium supplemented with 2% patient autologous serum and without any animal-derived materials such as trypsin in the culturing process. We applied the AFD in five patients with diabetic ulcers and investigated its safety and efficacy. As the primary endpoint, we defined 'wound bed improvement' according to the percentage of granulation area to the whole wound area on day 21, and 60% or higher was regarded as improved. The mean age of the patients was 60·6 years and the mean duration of the ulcer was 22·6 months. In the evaluation of the primary endpoint, the 'wound bed' was improved in all patients [proportion of improvement: 100%, 95% confidence interval (CI): 48% to 100%]. Three patients had complete wound healing within 12 weeks after application and two patients had >80% wound healing at 12 weeks. Side effects were not serious. Our AFD may be a safe and effective treatment of diabetic ulcers.

A framework for assessing Health Economic Evaluation (HEE) quality appraisal instruments

Background

Health economic evaluations support the health care decision-making process by providing information on costs and consequences of health interventions. The quality of such studies is assessed by health economic evaluation (HEE) quality appraisal instruments. At present, there is no instrument for measuring and improving the quality of such HEE quality appraisal instruments. Therefore, the objectives of this study are to establish a framework for assessing the quality of HEE quality appraisal instruments to support and improve their quality, and to apply this framework to those HEE quality appraisal instruments which have been subject to more scrutiny than others, in order to test the framework and to demonstrate the shortcomings of existing HEE quality appraisal instruments.

Methods

To develop the quality assessment framework for HEE quality appraisal instruments, the experiences of using appraisal tools for clinical guidelines are used. Based on a deductive iterative process, clinical guideline appraisal instruments identified through literature search are reviewed, consolidated, and adapted to produce the final quality assessment framework for HEE quality appraisal instruments.

Results

The final quality assessment framework for HEE quality appraisal instruments consists of 36 items organized within 7 dimensions, each of which captures a specific domain of quality. Applying the quality assessment framework to four existing HEE quality appraisal instruments, it is found that these four quality appraisal instruments are of variable quality.

Conclusions

The framework described in this study should be regarded as a starting point for appraising the quality of HEE quality appraisal instruments. This framework can be used by HEE quality appraisal instrument producers to support and improve the quality and acceptance of existing and future HEE quality appraisal instruments. By applying this framework, users of HEE quality appraisal instruments can become aware of methodological deficiencies inherent in existing HEE quality appraisal instruments. These shortcomings of existing HEE quality appraisal instruments are illustrated by the pilot test.

A framework for assessing Health Economic Evaluation (HEE) quality appraisal instruments

BACKGROUND

Health economic evaluations support the health care decision-making process by providing information on costs and consequences of health interventions. The quality of such studies is assessed by health economic evaluation (HEE) quality appraisal instruments. At present, there is no instrument for measuring and improving the quality of such HEE quality appraisal instruments. Therefore, the objectives of this study are to establish a framework for assessing the quality of HEE quality appraisal instruments to support and improve their quality, and to apply this framework to those HEE quality appraisal instruments which have been subject to more scrutiny than others, in order to test the framework and to demonstrate the shortcomings of existing HEE quality appraisal instruments.

METHODS

To develop the quality assessment framework for HEE quality appraisal instruments, the experiences of using appraisal tools for clinical guidelines are used. Based on a deductive iterative process, clinical guideline appraisal instruments identified through literature search are reviewed, consolidated, and adapted to produce the final quality assessment framework for HEE quality appraisal instruments.

RESULTS

The final quality assessment framework for HEE quality appraisal instruments consists of 36 items organized within 7 dimensions, each of which captures a specific domain of quality. Applying the quality assessment framework to four existing HEE quality appraisal instruments, it is found that these four quality appraisal instruments are of variable quality.

CONCLUSIONS

The framework described in this study should be regarded as a starting point for appraising the quality of HEE quality appraisal instruments. This framework can be used by HEE quality appraisal instrument producers to support and improve the quality and acceptance of existing and future HEE quality appraisal instruments. By applying this framework, users of HEE quality appraisal instruments can become aware of methodological deficiencies inherent in existing HEE quality appraisal instruments. These shortcomings of existing HEE quality appraisal instruments are illustrated by the pilot test.

An exploratory clinical trial for combination wound therapy with a novel medical matrix and fibroblast growth factor in patients with chronic skin ulcers: a study protocol

BACKGROUND

Chronic skin ulcers such as diabetic ulcers and venous leg ulcers are increasing and are a costly problem in health care. We have developed a novel artificial dermis, collagen/gelatin sponge (CGS), that is capable of the sustained release of basic fibroblast growth factor (bFGF) for more than 10 days. The objective of this study was to investigate the safety and efficacy of CGS impregnated with bFGF in the treatment of chronic skin ulcers. Methods/

DESIGN

Seventeen patients (≥ 20 years of age) with chronic skin ulcers that have not healed by conventional therapy for at least 4 weeks are being recruited. Patients will be applied with CGS impregnated with bFGF of 7 μg/cm(2) or 14 μg/cm(2) after debridement, and the wound bed improvement will be assessed 14 days after application. "Wound bed improvement" is defined as a granulated and epithelialized area on Day 14 in proportion to the baseline wound area after debridement of 50% or higher. Patients will be followed up until 28 days after application to observe the adverse events related to the application of CGS.

CONCLUSION

This study has been designed to address the safety and efficacy of CGS impregnated with bFGF. If successful, this intervention may be an alternative to bioengineered skin substitutes and lead to substantial and important changes in the management of chronic skin ulcers such as diabetic ulcers and venous ulcers.

Use of platelet rich plasma gel on wound healing: a systematic review and meta-analysis

OBJECTIVE

Autologous platelet rich plasma is an advanced wound therapy used in hard-to-heal acute and chronic wounds. To better understand the use and clinical outcomes of the therapy, a systematic review of the published literature in cutaneous wounds was performed.

METHODS

Electronic and hand searches for randomized controlled trials and comparative group studies using platelet rich plasma therapy in cutaneous wounds and published over the last 10 years was conducted. Eligible studies compared the treatment to standard care or other interventions. All citations were screened and eligible studies were assessed for validity, quality, and bias using accepted scoring methods. The primary outcomes were effect of platelet rich plasma and control wound care on wound healing and related healing measurements. Secondary outcomes related to healing such as infection, pain, exudate, adverse events, and quality of life were also considered. The meta-analysis utilized appropriate statistical methods to determine the overall treatment effect on chronic and acute wound healing and infection.

RESULTS

The search terms resulted in 8577 citations and after removing duplicates and screening for protocol eligibility, a total of 24 papers were used. The meta-analysis of chronic wound studies revealed platelet rich plasma therapy is significantly favored for complete healing. The meta-analysis of acute wounds with primary closure studies demonstrated that presence of infection was reduced in platelet rich plasma treated wounds.

CONCLUSIONS

This systematic review and meta-analysis of platelet rich plasma therapy in cutaneous wounds showed complete and partial wound healing was improved compared to control wound care.

Foslip®-based photodynamic therapy as a means to improve wound healing

BACKGROUND

Collagen matrices as substitution for connective tissue are known to promote wound healing. Photodynamic therapy has been anecdotally associated with improved wound healing and reduced scarring. The present study investigates the impact of collagen based scaffolding material, embedded with a liposomal formulation of meta-tetra (hydroxyphenyl) chlorin (mTHPC, Foslip(®)) and photodynamic therapy on wound healing in mice.

METHODS

After incision in the neck region, two different types of collagen material, previously incubated with Foslip(®) at different concentrations, were implanted followed by illumination at 652nm (10J/cm(2), 100mW/cm(2)). Mice were imaged daily up to two weeks, whereafter excision was performed and pathological analysis.

RESULTS

Scab detachment was observed at day seven for controls whereas it occurred as early as three days for PDT at the lowest concentrations. In the latter conditions, final matrix remodelling could be observed as evidenced by elastin neosynthesis.

CONCLUSIONS

Topical application of low dose Foslip(®) in a collagen matrix followed by illumination considerably accelerates wound healing.

Treatment of non-healing wounds with autologous bone marrow cells, platelets, fibrin glue and collagen matrix

BACKGROUND AIMS

Recalcitrant diabetic wounds are not responsive to the most common treatments. Bone marrow-derived stem cell transplantation is used for the healing of chronic lower extremity wounds.

METHODS

We report on the treatment of eight patients with aggressive, refractory diabetic wounds. The marrow-derived cells were injected/applied topically into the wound along with platelets, fibrin glue and bone marrow-impregnated collagen matrix.

RESULTS

Four weeks after treatment, the wound was completely closed in three patients and significantly reduced in the remaining five patients.

CONCLUSIONS

Our study suggests that the combination of the components mentioned can be used safely in order to synergize the effect of chronic wound healing.

Wound care: the role of advanced wound-healing technologies

Wound repair and regeneration is a highly complex combination of matrix destruction and reorganization. Although major hurdles remain, advances during the past generation have improved the clinician's armamentarium in the medical and surgical management of this problem. The purpose of this article is to review the current literature regarding the pragmatic use of three of the most commonly used advanced therapies: bioengineered tissue, negative-pressure wound therapy, and hyperbaric oxygen therapy, with a focus on the near-term future of wound healing, including stem cell therapy.

Prospective randomized controlled study of a Chinese herbal medicine compound Tangzu Yuyang Ointment for chronic diabetic foot ulcers: a preliminary report

AIM OF THE STUDY

The purpose of this study was to evaluate the efficacy and safety of a topical Chinese herbal medicine (CHM) compound Tangzu Yuyang Ointment (TYO) for treatment of chronic diabetic foot ulcers.

MATERIALS AND METHODS

This multi-center, prospective, randomized, controlled and add-on clinical trial was conducted at seven centers in the China mainland. Fifty-seven patients with chronic diabetic foot ulcers of Wagner's ulcer grade 1-3 were enrolled in this study. Patients who were randomly assigned to the control group (n=28) received standard wound therapy (SWT), whereas those randomized to the treatment group (n=28) received SWT plus topical TYO. Only 48 patients who finished 24 weeks of observations were entered for data analysis.

RESULTS

The TYO and SWT groups were comparable for baseline characteristics. Ulcer improvement was 79.2% in the TYO group and 41.7% in the SWT group (P=0.017) at 12 weeks, and 91.7% vs. 62.5% (P=0.036) at 24 weeks. The number of ulcers that were completely healed at 4, 12 and 24 weeks was similar in both groups, as were the numbers of adverse events. Healing time was 96±56 days (n=19) in the TYO group and 75±53 days (n=14) in the SWT group (P=0.271).

CONCLUSION

TYO plus SWT is more effective than SWT in the management of chronic diabetic foot ulcers and has few side-effects.

Active wound coverings: bioengineered skin and dermal substitutes

Extensive skin loss and chronic wounds present a significant challenge to the clinician. With increased understanding of wound healing, cell biology, and cell culture techniques, various synthetic dressings and bioengineered skin substitutes have been developed. These materials can protect the wound, increase healing, provide overall wound coverage, and improve patient care. The ideal skin substitute may soon become a reality.

Regulation of keratinocyte signaling and function via changes in epidermal growth factor presentation

Motivated by the need for bioactive materials that can accelerate dermal wound healing, this work describes the responses of keratinocytes to covalently immobilized epidermal growth factor (EGF) and how differences in the physical presentation of this growth factor affect cell function. Specifically, human keratinocytes were cultured with EGF delivered in soluble form, immobilized in a homogeneous pattern or immobilized in a gradient pattern, followed by analysis of cellular signaling, proliferation and migration. By changing the manner in which EGF was presented, keratinocyte behavior was dramatically altered. Keratinocytes responded to immobilized EGF patterns with high EGF receptor (EGFR) but low ERK1/2 and Akt phosphorylation, accompanied by low proliferation, high migratory activity and coordinated cell alignment. In contrast, keratinocytes treated with soluble EGF experienced lower EGFR but higher ERK1/2 and Akt phosphorylation and displayed a highly proliferative, rather than migratory, phenotype. Keratinocytes also responded to differences in immobilized EGF patterns, as migration was fastest upon immobilized gradients of EGF. A better understanding the interaction of cells with soluble vs. immobilized growth factors can help elucidate native healing events and achieve greater control over cell function, which may be useful in the development of wound repair treatments for many types of tissues.

Diabetic foot ulcers: effects of hyperoxia and SDF-1α on endothelial progenitor cells

Diabetes mellitus is a common disease afflicting many people. In addition to coronary artery disease, diabetic retinopathy and renal failure, diabetic patients face abnormal wound healing and have increased lower extremity ulcers and amputations. In diabetes, wound healing is altered due to both macrovascular and microvascular processes. While the former can be addressed with surgical intervention, the latter is more difficult to correct. Neovascularization within the granulation tissue via angiogenesis and vasculogenesis is critical for wound healing. Endothelial progenitor cells (EPCs) have been implicated in vasculogenesis. Mobilization of EPCs from the bone marrow is impaired in diabetes and homing of EPCs to the wound is also abnormal. Recent studies show that hyperoxia and administration of exogenous stromal-derived factor-1α increases circulatory and wound levels of EPCs and improves wound healing in diabetic mice. These findings have great potential for translation into human counterparts as the treatment for this prevalent disease matures.