Chronic wounds

Efficacy and safety of the freeze-dried cultured human keratinocyte lysate, LyphoDermtm 0.9%, in the treatment of hard-to-heal venous leg ulcers

LyphoDerm (XCELLentis, Belgium) is an end-sterilized, freeze-dried lysate from cultured allogeneic epidermal keratinocytes, formulated into a hydrophilic gel. Its efficacy and safety were evaluated, in combination with standard care (hydrocolloid dressing and compression therapy), in 194 patients suffering from hard-to-heal (lasting more than 6 weeks and not responding to conventional therapy) venous leg ulcers. Two control groups received standard care, with or without vehicle, respectively. Patients had a median age of 67.5 years and the majority were females (61%). The median duration of the ulcer was 43 weeks and in 39% of the subjects it had been present for more than 1 year. Thirty-eight percent of the patients in the standard care + LyphoDerm group had complete ulcer healing within 24 weeks (primary end point) compared to 27% of patients in the standard care + vehicle pooled groups (P = 0.114) in the "as treated" intent-to-treat cohort (37% vs. 27% in the "as randomized intent-to-treat cohort; p = 0.137). In the subgroup of patients with enlarging ulcers, the difference between the two groups was significant (30% vs. 11%; p = 0.024 in the "as treated" intent-to-treat cohort and 31% vs. 9%; p = 0.005 in the "as randomized" intent-to-treat cohort). LyphoDerm was well tolerated and safe, and no differences in the frequency of adverse events were noted between the treatment groups. Although the primary objective of the study was not achieved, the exploratory analysis carried out in patients with enlarging ulcers suggests that LyphoDerm could offer a new prospect for the treatment of patients with venous ulcers that may prove to be a significant adjunct to the overall provision of care.

Platelet gel for healing cutaneous chronic wounds

Wound healing is a specific host immune response for restoration of tissue integrity. Experimental studies demonstrated an alteration of growth factors activity due to their reduced synthesis, increased degradation and inactivation. In wound healing platelets play an essential role since they are rich of alpha-granules growth factors (platelet derived growth factor--PDGF; transforming growth factor-beta--TGF-beta; vascular endothelial growth factor--VEGF). Topical use of platelet gel (PG), hemocomponent obtained from mix of activated platelets and cryoprecipitate, gives the exogenous and in situ adding of growth factors (GF). The hemocomponents are of autologous or homologous origin. We performed a technique based on: multicomponent apheretic procedure to obtain plasma rich platelet and cryoprecipitate; manual processing in an open system, in sterile environment, for gel activation. Every step of the gel synthesis was checked by a quality control programme. The therapeutic protocol consists of the once-weekly application of PG. Progressive reduction of the wound size, granulation tissue forming, wound bed detersion, regression and absence of infective processes were considered for evaluating clinical response to hemotherapy. 24 patients were enrolled. They had single or multiple cutaneous ulcers with different ethiopathogenesis. Only 3 patients could perform autologous withdrawal; in the others homologous hemocomponent were used, always considering suitability and traceability criteria for transfusional use of blood. Complete response was observed in 9 patients, 2 were subjected to cutaneous graft, 4 stopped treatment, 9 had partial response and are still receiving the treatment. In each case granulation tissue forming increased following to the first PG applications, while complete re-epithelization was obtained later. Pain was reduced in every treated patient. Topical haemotherapy with PG may be considered as an adjuvant treatment of a multidisciplinary process, useful to enhance therapy of cutaneous ulcers.

Surgical treatment of the infected diabetic foot

Foot infections are common in the diabetic patient. Early recognition, proper assessment, and prompt intervention are vital. A combination of surgery and antibiotics is mandatory in virtually all foot infections. The aim of surgery is 2-fold: first, to control the infection, and second, to attempt to salvage the leg. The eventual goal is always to preserve a functional limb. Foot deformities resulting from surgery may cause reulceration and a high morbidity. The surgical treatment of the infection largely consists of draining of pus and removal of all necrotic and infected tissue. Frequently, revascularization of the foot is needed to save the limb; thus, there must be a close cooperation with the vascular surgical service. The surgeon must have a thorough knowledge of foot anatomy and must be familiar with the defects in wound healing that are caused by diabetes. The outcome of surgery mainly depends on the skill, care, and experience of the surgeon. The best results are achieved within a multidisciplinary setting.

Clinical and economic impact of Apligraf for the treatment of nonhealing venous leg ulcers

BACKGROUND

Controlled studies have shown that Apligraf(R) (Organogenesis Inc., Canton, USA) is more economical and more effective at healing venous leg ulcers (VLUs) than compression therapy alone. However, the clinical and economic impact of Apligraf on healing VLUs in clinical practice has not been fully examined.

METHODS

A medical chart review was conducted of patients who were treated with Apligraf for one or more nonhealing VLUs over a 2-year period at the Henry Ford Hospital. Following Apligraf treatment, patients were followed for up to 9 months. Primary clinical outcome measures were mean change in baseline ulcer size (cm2) per week and percent reduction in baseline ulcer size at final study visit. Economic evaluation of Apligraf treatment was based on VLU-related medical care costs (US$) in relation to ulcer size (cm2) changes before and after Apligraf therapy.

RESULTS

Thirteen patients with 21 chronic VLUs were treated with Apligraf. All had at least one comorbidity, most commonly hypertension (38%). Twelve patients were known to have had a prior history of VLU. At baseline, mean ulcer duration was 23.9 months and median ulcer size was 13.5 cm2; for the 6 months preceding Apligraf treatment, in which patients received conventional compression therapy, mean ulcer size increased +0.72 cm2 per week. During the Apligraf post-treatment study period, mean ulcer size decreased by -2.37 cm2 per week. At final clinic visit, ulcers exhibited an average 60.5% reduction in baseline size; 21 ulcers (n = 13) showed 75% or greater reduction in size, compared with baseline. Economic data were available for five patients; among these individuals ulcer-related medical costs per unit change in ulcer size were lower following Apligraf treatment relative to such costs with conventional compression therapy applied during the Apligraf pretreatment period.

CONCLUSIONS

In a clinical practice setting, Apligraf is more effective and more economical at healing VLUs than conventional therapy alone.

Wound care in geriatrics

Wound care is a crucial aspect in caring for the geriatric population. It is important to recognize a wound when it begins and know the proper treatment once a wound develops. First, it is important to assess the wound and determine the type of wound that is being dealt with. One must establish whether the wound is acute of chronic. Then a proper treatment plan must be devised. This article will take you through step by step process of different types of wounds and the proper treatment of those wounds that commonly occur within the geriatric population.

Wound bed preparation: a systematic approach to wound management

The healing process in acute wounds has been extensively studied and the knowledge derived from these studies has often been extrapolated to the care of chronic wounds, on the assumption that nonhealing chronic wounds were simply aberrations of the normal tissue repair process. However, this approach is less than satisfactory, as the chronic wound healing process differs in many important respects from that seen in acute wounds. In chronic wounds, the orderly sequence of events seen in acute wounds becomes disrupted or "stuck" at one or more of the different stages of wound healing. For the normal repair process to resume, the barrier to healing must be identified and removed through application of the correct techniques. It is important, therefore, to understand the molecular events that are involved in the wound healing process in order to select the most appropriate intervention. Wound bed preparation is the management of a wound in order to accelerate endogenous healing or to facilitate the effectiveness of other therapeutic measures. Experts in wound management consider that wound bed preparation is an important concept with significant potential as an educational tool in wound management. This article was developed after a meeting of wound healing experts in June 2002 and is intended to provide an overview of the current status, role, and key elements of wound bed preparation. Readers will be able to examine the following issues; the current status of wound bed preparation; an analysis of the acute and chronic wound environments; how wound healing can take place in these environments; the role of wound bed preparation in the clinic; the clinical and cellular components of the wound bed preparation concept; a detailed analysis of the components of wound bed preparation.

Does low output laser stimulation enhance the healing of crural ulceration? Some critical remarks

The objective of the experiment was to evaluate the impact of laser stimulation on crural ulceration healing. Three groups were established at random from patients with crural ulceration: A, B and C. Group A included 21 patients, group B included 22 patients and group C, 22 patients. Patients in all groups were treated with pharmaceuticals and with compressive therapy. The ulcers in group A were additionally irradiated with laser light of wavelength 810 nm, so that a dose of 4 J/cm2 was applied in each procedure. Patients in group B were additionally subjected to a blind test (with placebo in the form of quasi-laser therapy). At the end of the treatment a statistically significant reduction of the area and volume of the ulcers was found in all groups. No statistically significant difference was found between the groups in terms of average rate of change per week of the relative area of ulceration and average rate of change per week of the relative volume of ulceration. Reduction of infected area was observed in all groups, but a significant change was only observed in group C. No significant impact of laser light (lambda=810 nm, P=65 mW, p=4 J/cm2) on any of the stages of ulceration healing was observed.

Galectins-3 and -7, but not galectin-1, play a role in re-epithelialization of wounds

Disorders of wound healing characterized by impaired or delayed re-epithelialization are a serious medical problem. These conditions affect many tissues, are painful, and are difficult to treat. In this study, using cornea as a model, we demonstrate for the first time the importance of carbohydrate-binding proteins galectins-3 and -7 in re-epithelialization of wounds. In two different models of corneal wound healing, re-epithelialization of wounds was significantly slower in galectin-3-deficient (gal3(-/-)) mice compared with wild-type (gal3(+/+)) mice. In contrast, there was no difference in corneal epithelial wound closure rates between galectin-1-deficient and wild-type mice. Quantitation of the bromodeoxyuridine-labeled cells in gal3(+/+) and gal3(-/-) corneas revealed that corneal epithelial cell proliferation rate is not perturbed in gal3(-/-) corneas. Exogenous galectin-3 accelerated re-epithelialization of wounds in gal3(+/+) mice but, surprisingly, not in the gal3(-/-) mice. Gene expression analysis using cDNA microarrays revealed that healing corneas of gal3(-/-) mice contain markedly reduced levels of galectin-7 compared with those of gal3(+/+) mice. More importantly, unlike galectin-3, galectin-7 accelerated re-epithelialization of wounds in both gal3(-/-) and gal3(+/+) mice. In corresponding experiments, recombinant galectin-1 did not stimulate the corneal epithelial wound closure rate. The extent of acceleration of re-epithelialization of wounds with both galectin-3 and galectin-7 was greater than that observed in most of the published studies using growth factors. These findings have broad implications for developing novel therapeutic strategies for treating nonhealing wounds.

Urgotul: a novel non-adherent lipidocolloid dressing

Urgotul belongs to a new class of non-adherent dressings: the lipidocolloid dressings. It is composed of an open weave polyester mesh impregnated with hydrocolloid polymers dispersed within petrolatum. The first clinical trial data are presented. Efficacy and safety were evaluated in a multicentre non-comparative trial involving 92 patients treated to healing or up to 4 weeks. Adult outpatients with acute wounds (n = 34), leg ulcers (n = 24), other chronic wounds (n = 14) or with second-degree burns (n = 20) were included. Results showed 32.4% (n = 11) of the acute wounds, 12.5% (n = 3) of the leg ulcers and 14.3% (n = 2) of the other chronic wounds completely healed before 4 weeks. Surface areas decreased on average by 76.4%, 63.5% and 44.2% at study endpoint respectively. For burns, 19 patients healed (95%) within 5-19 days. A total of 771 dressing changes were performed during the course of the study. Dressing application was considered as easy or very easy in 90% or more of the changes and there was no difficulty in removing the dressing in about 95% of the cases. Safety was good with five reports of a transitory local adverse event, probably dressing-related, being observed, two patients (2.2%) prematurely stopped treatment because of moderate periwound erythema. Urgotul is a highly promising new dressing which is currently undergoing further comparative clinical evaluation.

Factors that influence healing in chronic venous ulcers treated with cryopreserved human epidermal cultures

BACKGROUND

Cryopreserved epidermal cultures (CEC) offer an "off the shelf" treatment for chronic wounds. These cultures are derived from neonatal foreskin and grow rapidly in vitro to form epidermal sheets. They do not require a biopsy from the patient, an advantage compared to autografts. They seem to act as a biological dressing, stimulating epithelialization from the wound edges and adnexae, probably through growth factor release.

OBJECTIVE

To summarize our recent experience with the use of CEC in chronic venous leg ulcers and to determine the factors that influence healing in chronic venous ulcers treated with CEC.

PATIENTS AND METHODS

A single arm, open label study including a total of 11 patients with documented venous ulcers was performed. The study involved the application of cryopreserved epidermal cultures every other week to nonhealing leg ulcers for a total of 12 weeks or until complete healing of the ulcer.

RESULTS

A total of 11 patients with one or more leg ulcers were treated. The average age was similar in healed and unhealed groups. Seven patients completely healed after an average of 4.14 CEC applications. Four patients did not heal after a total of 12 CEC applications.

CONCLUSION

Predictors for failure to heal after CEC application in our patients were long wound duration, wound size, presence of lipodermatosclerosis, and history of failed prior split-thickness skin grafts.

Effect of age and hypoxia on TGFbeta1 receptor expression and signal transduction in human dermal fibroblasts: impact on cell migration

Wound healing is critically affected by age, ischemia, and growth factors such as TGFbeta1. The combined effect of these factors on fibroblast migration, an essential component of wound healing, is poorly understood. To address this deficiency, we examined expression of TGFbeta receptor type I and II (TGFbetaRI and RII) under normoxia or hypoxia (1% O(2)) in cultured human dermal fibroblasts (HDFs) from young (ages 24-33) and aged (ages 61-73) adults. TGFbetaRI and RII expression was similar in both groups under normoxia. Hypoxia did not alter receptor levels in young HDFs but significantly decreased TGFbetaRI in aged cells (12 and 43%, respectively). Additionally, young cells displayed a 50% increase in activation of p42/p44 mitogen-activated kinase by TGFbeta1 (2-200 pg/ml) under hypoxia while aged cell levels of active p42/p44 decreased up to 24%. To determine functional outcomes of these findings, we measured the migratory capacity of the cells on type I collagen using a gold salt migration assay. Hypoxia increased the migratory index (MI) of young HDFs over normoxia by 30% but had no effect on aged cells. Under normoxia, TGFbeta1 (1-1000 pg/ml) increased young HDF migration in a concentration-dependent manner up to 109% over controls but minimally increased aged HDF migration (37%). Under hypoxia, TGFbeta1 significantly increased young cell MI at all concentrations but was without effect on the aged HDF response. These data demonstrate that aged fibroblasts have an impaired migratory capacity with complete loss of responsiveness to hypoxia and deficits in the migratory and signal transduction responsiveness to TGFbeta1 that may partly explain diminished healing capabilities often observed in aged patients.

Chlamydia pneumoniae and chronic skin wounds: a focused review

The genus, Chlamydophilia, as obligate intracellular pathogens, induce chronic scarring in humans. Chlamydia pneumoniae, a common cause of pneumonia, infects endothelial cells and circulating macrophages. Evidence that C. pneumoniae is an opportunistic pathogen in chronic skin ulcers and other inflammatory skin conditions analogous to its role in atherosclerosis is reviewed.

Factors influencing the development of decubitus ulcers in critically ill surgical patients

INTRODUCTION

Decubitus ulcers confer significant morbidity to critically ill patients. We sought to determine which patient factors contributed to the formation of decubitus ulcers in our critically ill patients, and hypothesized that these ulcers occurred most often in elderly patients with lengths of stay >7 days and high severity of illness.

METHODS

This study was conducted prospectively in two phases. Phase I provided an initial analysis of patients who developed decubitus ulcers in the surgical intensive care unit (ICU) of New York Weill Cornell Center from January 1, 1993, to June 1, 1997. In phase II of the study, a comparison study was made for patients with ICU length of stay (ULOS) >7 days admitted to the same ICU from January 1, 1998, to August 31, 1998. Age, APACHE III score, systemic inflammatory response syndrome (SIRS score), multiple organ dysfunction syndrome (MODS) score, admission status, days without nutrition, ULOS, mortality, days to formation of decubitus ulcers, Cornell ulcer risk score, and other demographic features were recorded. Univariate and multivariate analysis of variance were performed to analyze independent risk factors for development of decubitus ulcers; p <.05.

RESULTS

In phase I, 2,615 patients were admitted to surgical ICU over the study period. One hundred and one decubitus ulcers occurred (incidence 3.8%) during phase I, but the incidence of decubitus ulcers increased significantly over time to 9% (p <.01). Thirty-three decubitus ulcers occurred among the 412 patients (incidence 8.0%) during phase II. Multivariate analysis revealed that emergent admission (odds ratio [OR] 36.00, 95% confidence interval [CI] CI 0.2290-0.7694), age (OR 1.08, 95% CI 0.0026-0.0131), days in bed (OR 1.05, 95% CI -0.0013-0.0156, and days without nutrition (OR 0.51, 95% CI -0.1095--0.0334) were independent predictors of a decubitus ulcer.

CONCLUSIONS

The incidence of decubitus ulcers is increasing in critically ill patients. Emergency ICU admission and ULOS >7 days in elderly patients confer significant risk for the formation of decubitus ulcers. Specific interventions targeting this high-risk population that may be instituted to decrease the incidence of decubitus ulcers include early nutrition, early mobilization, and possibly less noxious bedding surfaces.

Cytokines, growth factors, and plastic surgery

Numerous inflammatory cytokines and growth factors have been identified and are known to be essential for normal wound healing and host defense, and many have been implicated in disease states treated by plastic surgeons. Cytokines and growth factors are members of a large functional group of polypeptide regulatory molecules secreted by different cell lines. These peptides exert their influence through autocrine and paracrine fashions within sites of injury and repair. Although cytokines and growth factors are crucial in initiating, sustaining, and regulating the postinjury response, these same molecules have been implicated in impaired wound healing, abnormal scarring, and chronic cutaneous diseases. Therapeutic manipulation of inflammatory mediators in normal and impaired wounds has been performed, with mixed clinical results, but evolving strategies such as gene therapy, as well as further characterization of the cellular-mechanism cytokines and growth-factor triggers, will further add to our therapeutic options. This article discusses the current understanding of important cytokines and growth factors involved in the normal injury response and then addresses pathological states associated with an inappropriate expression of these mediators. Finally, a summary of various cytokine and growth factor-directed strategies being used in impaired wound healing states is presented.

Chronic venous insufficiency and venous leg ulceration

Venous ulcers are the most common form of leg ulcers. Venous disease has a significant impact on quality of life and work productivity. In addition, the costs associated with the long-term care of these chronic wounds are substantial. Although the exact pathogenic steps leading from venous hypertension to venous ulceration remain unclear, several hypotheses have been developed to explain the development of venous ulceration. A better understanding of the current pathophysiology of venous ulceration has led to the development of new approaches in its management. New types of wound dressings, topical and systemic therapeutic agents, surgical modalities, bioengineered tissue, matrix materials, and growth factors are all novel therapeutic options that may be used in addition to the "gold standard," compression therapy, for venous ulcers. This review discusses current aspects of the epidemiology, pathophysiology, clinical presentation, diagnostic assessment, and current therapeutic options for chronic venous insufficiency and venous ulceration. (J Am Acad Dermatol 2001;44:401-21.)

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be familiar with the 3 main types of lower extremity ulcers and should improve their understanding of the epidemiology, pathogenesis, risk factors, clinical presentation, diagnostic assessment, and current therapies for chronic venous insufficiency and venous ulcers.

Modern application of high voltage stimulation for enhanced healing of venous crural ulceration

The objective of this paper was to evaluate the effect of high voltage stimulation (HVS) on the process of healing of crural ulceration. Three comparative groups of patients, A, B and C, were drawn at random from patients with venous crural ulceration. Thirty-three patients in group A were subjected to treatment with HVS. In the course of treatment, doubled-peak monophasic impulses of a total duration of 0.1 ms and frequency of 100 Hz were applied. The voltage was 100 V. Group B, made up of 32 patients treated with topically applied medicine, and group C, made up of 14 patients treated with Unna's boot were used as control. In all patients in all groups (A, B and C) a significant reduction in wound size in relation to baseline was found. The rate of wound area change was highest in group A. The rate of pus cleansing was significantly highest in group A. The degree of granulation after 2 weeks was significantly greater in group A than in the other groups (P<0.003). High voltage stimulation was an efficient method of enhancement of the healing of crural ulceration.

Graftskin heals an ulcer on an amputation stump

BACKGROUND

A 51-year-old man presented with a chronic ulcer of 28 years' duration on the amputation stump of his right foot. The prosthesis was aggravating the ulcer, despite multiple therapies.

OBJECTIVE

To heal the ulcer and avoid a below-the-knee amputation. Graftskin, a bilayered living skin construct, was applied.

METHODS

Graftskin was sutured in place following gentle debridement. Pentoxifylline was given to improve circulation. The dressing was changed 5 days after Graftskin application, then weekly for 7 weeks.

RESULTS

Crusting was evident at 3 weeks, with an underlying white coating at 4 weeks. By 7 weeks, full reepithelialization was present under the crust and no ulceration remained. Over succeeding weeks the ulcer bed became flush with the surrounding skin. The patient's pain ceased, and some sensation and warmth returned to the stump.

CONCLUSION

Graftskin treatment successfully healed a chronic ulcer, possibly preventing a more extensive amputation.

Pinch graft skin transplantation for leg ulcers in primary care

Pinch grafting offers an alternative approach to conventional management of chronic leg ulcers, and is particularly well suited for venous and diabetic ulcers. Relevant literature from 1872-1998 was reviewed. The method of pinch grafting is described here in detail, and is illustrated by two case reports. Since pinch grafting hastens the healing of granulating wounds, is easy to perform and does not require strict immobilisation, a revival of the method, with adaptation for primary care, should be encouraged.

Human three-dimensional fibroblast cultures express angiogenic activity

Human neonatal fibroblasts were cultured on a lactate-glycollate copolymer scaffold for 12-16 days to form a three-dimensional dermal equivalent tissue. The cellular content of vascular endothelial growth factor (VEGF) mRNA in these three-dimensional cultures was 22-fold greater than that observed in the same fibroblasts grown as monolayers. No induction was shown by hepatocyte growth factor (HGF) or angiopoietin 1 indicating that the effect was specific to VEGF. The predominant VEGF splice variant, detected by RT-PCR corresponded to the 121 amino acid form, with less of the 165 amino acid form. The cell-associated forms (189 and 206 amino acids) comprised less than 1% of the total VEGF mRNA. VEGF and HGF proteins, determined by ELISA, were secreted in physiologically significant amounts, 0.5-4 ng per 24 h/10(6) cells. Conditioned medium from the three-dimensional cultures stimulated proliferation of endothelial cells in a dose-dependent manner and induced cellular expression of integrin alpha(v)beta(3). Conditioned medium from the same dermal fibroblasts cultured in monolayer showed little angiogenic activity in any of these assays. Using the chorioallantoic membrane (CAM) angiogenesis assay, the cultures stimulated blood vessel production 2.8-fold over scaffold alone. VEGF-neutralizing antibody reduced the vessel development in the CAM to the level in the scaffold control. Anti-HGF antibody had no significant effect. In conclusion, three-dimensional cultures of dermal equivalent tissue express angiogenic activity to a greater extent than monolayer cultures, some of which can be assigned to VEGF.

Vascular infections: medical and surgical therapies

Vascular infections are a serious problem, often associated with high morbidity and mortality. This article reviews the etiology, pathophysiology, risk factors, and treatment of surgical wound infections, prosthetic graft infections, aortoenteric fistulas (AEFs), and infected vascular ulcers. The primary cause of surgical wound infections is contamination by skin organisms during surgery. Prosthetic graft infections typically result from a progressive wound infection. Comorbid conditions are also related to vascular infections. Nurses should identify vascular patients at increased risk for infection, monitor them closely, and intervene to optimize the healing environment.

Diabetic foot ulcers: current concepts

Foot ulcerations and their sequelae remain a major source of morbidity for patients with diabetes mellitus. Often leading to infection, osteomyelitis, or gangrene, these lesions have consistently been ascertained as significant risk factors for subsequent lower extremity amputation. Hence education, appropriate foot care, and early intervention have assumed important roles in programs focused on amputation prevention. Multidisciplinary cooperation has been demonstrated as the most successful approach to the management and prevention of foot lesions in patients with diabetes. This article reviews the epidemiology, current understanding of the underlying pathophysiology, and treatment rationale for diabetic foot ulcerations. Such knowledge is essential in the overall management of these complicated patients and, when incorporated into daily practice, can significantly reduce the incidence and morbidity of foot disease in diabetes.

Impediments to wound healing

Chronic wounds will often heal in a short period of time if factors that inhibit wound healing are identified and managed. Recombinant growth factor therapy may provide an added stimulus to healing in certain types of chronic wounds. However, there remains no substitute for a physiologic environment conducive to tissue repair and regeneration, without which the efficacy of growth factor therapy is questionable. Some of the most commonly encountered and clinically significant impediments to wound healing include wound hypoxia, infection, presence of debris and necrotic tissue, use of anti-inflammatory medications, a diet deficient in vitamins or minerals, or general nutritional deficiencies, tumors, environmental factors, and metabolic disorders, such as diabetes mellitus. Treatment of chronic wounds should be directed against the main etiologic factors responsible for the wound. Moreover, factors that may impede healing must be identified and, if possible, corrected, for healing to occur.

Physiology and healing dynamics of chronic cutaneous wounds

In the last few decades, a great deal of progress has been made in understanding the cellular and biochemical interplay that comprises the normal wound healing response. This response is a complex process involving intricate interactions among a variety of different cell types, structural proteins, growth factors, and proteinases. The normal wound repair process consists of three phases--inflammation, proliferation, and remodeling--that occur in a predictable sequence and comprise a series of cellular and biochemical events. A review of the biochemical and physiologic processes that regulate wound healing and the cascade of cellular events that gives rise to the healing process is presented here.

Care of patients with leg ulcers: a nursing perspective

Care of patients with leg ulcers is challenging as well as rewarding. Recent advances in scientific knowledge about healing should be incorporated in the nursing care of leg ulcer patients. This article provides an update on the state of the science in the care of leg ulcers in geriatric patients, and focuses on assessment and local care of such ulcers. Ulcer assessment provides the basis for selecting therapies to maximize healing. Wound cleansing and appropriate dressings are essential to good patient outcomes. Furthermore, healing is enhanced when these interventions are combined with strategies that maximize oxygen to the ulcer, promote appropriate levels of activity, optimize perfusion through physiological positioning, and reduce mechanical shear through selection of proper footwear. Care of patients with leg ulcers provides the nurse an opportunity to apply pathophysiology, utilize scientific data, and function as an integral player on the wound care team.