Maggot versus conservative debridement therapy for the treatment of pressure ulcers

To define the efficacy and safety of maggot therapy, a cohort of 103 inpatients with 145 pressure ulcers was evaluated. Sixty-one ulcers in 50 patients received maggot therapy at some point during their monitored course; 84 ulcers in 70 patients did not. Debridement and wound healing could be quantified for 43 maggot-treated wounds and 49 conventionally treated wounds. Eighty percent of maggot-treated wounds were completely debrided, while only 48% of wounds were completely debrided with conventional therapy alone (p=0.021). Within 3 weeks, maggot-treated wounds contained one-third the necrotic tissue (p = 0.05) and twice the granulation tissue (p < 0.001), compared to non-maggot-treated wounds. Of the 31 measurable maggot-treated wounds monitored initially during conventional therapy, necrotic tissue decreased 0.2 cm(2) per week during conventional therapy, while total wound area increased 1.2 cm(2) per week. During maggot therapy, necrotic tissue decreased 0.8 cm(2) per week (p = 0.003) and total wound surface area decreased 1.2 cm2 per week (p = 0.001). Maggot therapy was more effective and efficient in debriding chronic pressure ulcers than were the conventional treatments prescribed. Patients readily accepted maggot therapy, and adverse events were uncommon.     

Negative pressure wound therapy for the treatment of infected wounds with exposed knee joint after patellar fracture

Treatment of soft tissue defects with exposed bones and joints, resulting from trauma, infection, and surgical complications, represents a major challenge. The introduction of negative pressure wound therapy has changed many wound management practices. Negative pressure wound therapy has recently been used in the orthopedic field for management of traumatic or open wounds with exposed bone, nerve, tendon, and orthopedic implants. This article describes a case of a patient with a large soft tissue defect and exposed knee joint, in which negative pressure wound therapy markedly improved wound healing. A 50-year-old man presented with an ulceration of his left knee with exposed joint, caused by severe wound infections after open reduction and internal fixation of a patellar fracture. After 20 days of negative pressure wound therapy, a granulated wound bed covered the exposed bones and joint.To our knowledge, this is the first report of negative pressure wound therapy used in a patient with a large soft tissue defect with exposed knee joint. Despite the chronic wound secondary to infection, healing was achieved through the use of the negative pressure wound therapy, thus promoting granulation tissue formation and closing the joint. We suggest negative pressure wound therapy as an alternative option for patients with lower limb wounds containing exposed bones and joints when free flap transfer is contraindicated. Our result added to the growing evidence that negative pressure wound therapy is a useful adjunctive treatment for open wounds around the knee joint.     

Enzymatic wound debridement

BACKGROUND: Clinical experience and existing research strongly support debridement as a necessary component of wound bed preparation when slough or eschar is present. Multiple techniques are available, but the indications for each technique and their efficacy are not clearly established. There is little evidence to guide the clinician in the selection of a safe, effective debridement method for the patient with a chronic wound. OBJECTIVES: We sought to identify evidence related to the efficacy of enzymatic debriding agents collagenase and papain-urea in the removal of necrotic tissue from the wound bed and its impact on wound healing. SEARCH STRATEGY: A systematic review of electronic databases was undertaken using key words: (1) debridement, (2) enzymatic debridement, (3) collagenases, (4) papain, (5) urea, and (6) papain-urea. All prospective and retrospective studies that compared enzymatic debridement using collagenase or papain-urea (with and without chlorophyllin) on pressure ulcers, leg ulcers, or burn wounds were included in the review. All studies that met inclusion criteria and were published between January 1960 and February 2008 were included. RESULTS: Collagenase ointment is more effective than placebo (inactivated ointment or petrolatum ointment) for debridement of necrotic tissue from pressure ulcers, leg ulcers, and partial-thickness burn wounds. Limited evidence suggests that a papain-urea-based ointment removes necrotic material from pressure ulcers more rapidly than collagenase ointment, but progress toward wound healing appears to be equivocal. Limited evidence suggests that treatment of partial-thickness burn wounds in children with collagenase ointment may require an equivocal time to treatment with surgical excision and that combination treatment may reduce the need for surgical excision. Insufficient evidence was found to determine whether collagenase ointment removes necrotic tissue from leg ulcers more or less rapidly than autolytic debridement enhanced by a polyacrylate dressing. IMPLICATIONS FOR PRACTICE: Enzymatic debriding agents are an effective alternative for removing necrotic material from pressure ulcers, leg ulcers, and partial-thickness wounds. They may be used to debride both adherent slough and eschar. Enzymatic agents may be used as the primary technique for debridement in certain cases, especially when alternative methods such as surgical or conservative sharp wound debridement (CSWD) are not feasible owing to bleeding disorders or other considerations. Many clinicians will select enzymes when CSWD is not an option. Clinical experience strongly suggests that combined therapy, such as initial surgical debridement followed by serial debridement using an enzymatic agent or enzymatic debridement along with serial CSWD, is effective for many patients with chronic, indolent, or nonhealing wounds.     

Topical negative pressure using a drainage pouch without foam dressing for the treatment of undermined pressure ulcers

Topical negative pressure is gaining popularity as an acute and chronic wound management technique. In general, foam dressing is applied to the wound surface to maintain negative pressure. Due to the potential for clogging by the foam dressing, topical negative pressure cannot be used when there is a high volume of necrotic tissue or massive infection present. In this study, topical negative pressure was applied using a drainage pouch without any dressing. Topical negative pressure was applied to 8 patients with 9 pressure ulcers complicated by undermining. This approach was effective in the treatment of all 9 ulcers and allowed the wounds to be visualized while maintaining negative pressure. Since this technique can be performed without foam dressing, it can be used to treat early-stage infectious pressure ulcers in which there is a lot of necrotic tissue. CONCLUSION: Topical negative pressure without dressing is an extremely effective treatment of pressure ulcers complicated by undermining.     

Use of negative pressure wound therapy with instillation and a reticulated open cell foam dressing with through holes in the acute care setting

Negative pressure wound therapy with instillation and dwell time (NPWTi‐d) is an automated system used to deliver, dwell, and remove topical solutions from the wound bed. Recently, a reticulated open cell foam dressing with through holes (ROCF‐CC) was developed, which assists with wound cleansing by removing thick exudate and infectious materials. We present our experience using NPWTi‐d with ROCF‐CC on complex wounds when complete surgical debridement was inappropriate because of medical instability, recurrent non‐viable tissue, or palliative treatment plan. For all wounds, NPWTi‐d with ROCF‐CC was initiated by instilling normal saline, acetic acid, or hypochlorous acid with 2 to 10 minutes of dwell time, followed by 0.5 to 4 hours of negative pressure. Dressings were changed every 2 to 3 days. Fourteen patients with multiple comorbidities were treated for wound types including diabetic foot ulcers, necrotising fasciitis, dehisced wounds, and pressure injuries. Duration of NPWTi‐d with ROCF‐CC ranged from 1 to 15 days, and at dressing changes, wounds showed improved granulation tissue formation, less malodour, less surrounding erythema, and demarcation of healthy skin from devitalised tissue. Based on these patients, adjunctive use of NPWTi‐d with ROCF‐CC provided a practical option for improving tissue quality in wounds for patients in whom surgical debridement was not possible or desired.     

整形外科复杂创面的负压吸引治疗

目的：探讨局部负压吸引技术处理整形外科复杂创面的方法和效果。方法：总结2007年～2009年笔者因复杂创面采用负压治疗的患者53例,男性33例,女性20例,年龄26～7l岁,创面面积6cm2～80cm2。结果：2例负压治疗后,新生上皮组织覆盖创面,治疗开始至愈合时间均为21天;51例行负压治疗后创面情况明显改善,二期行植皮或组织瓣转移等常规方法关闭创面（其中15例负压治疗后行全麻下清创）,术后创面均一期愈合,治疗时间最短者14天,最长者30天,平均治疗时间19天。结论：负压治疗是创面治疗的一次新进展,操作简便,易于掌握,能够彻底去除创面分泌物和坏死组织,优化创面条件,为整形修复提供良好组织基础,加速创面愈合。     

Grading system for gunshot injuries to the femoral diaphysis in civilians

One hundred patients had surgical treatment for a gunshot injury to the femur at the authors' hospital. Each injury was classified (Grade 1-3) based on clinical and radiographic signs of deep soft tissue necrosis. All patients were followed up for a minimum of 6 months (average, 18 months; range, 6 months-72 months). Grade 1 injuries are defined by small entry and exit wounds (< 2 cm) and the absence of high-energy characteristics on plain radiographs. Grade 2 gunshot injuries have small wounds (< 5 cm) and radiographic evidence of a high-energy injury. Grade 3 gunshot injuries are diagnosed by physical examination whenever necrotic muscle is present at the fracture site. Radiographs show extensive superficial and deep soft tissue disruption and segmental bone destruction. Seventy-nine patients with Grade 1 fractures had intramedullary nailing without wound exploration; all fractures united without infection. Seven patients with Grade 2 injuries had wound exploration; a necrotic cavity was discovered in five patients and three (43%) patients had deep infection develop. Fourteen patients with Grade 3 injuries had one or more debridements followed by skeletal stabilization, and seven patients (50%) had deep infection develop. Important decisions regarding wound debridement and fracture stabilization are determined by examination of the wound and radiographs, and not by determining muzzle velocity.     

Healing of diabetic foot ulcers and pressure ulcers with human skin equivalent: a new paradigm in wound healing

HYPOTHESIS: In patients with diabetic foot and pressure ulcers, early intervention with biological therapy will either halt progression or result in rapid healing of these chronic wounds. DESIGN: In a prospective nonrandomized case series, 23 consecutive patients were treated with human skin equivalent (HSE) after excisional debridement of their wounds. SETTING: A single university teaching hospital and tertiary care center. PATIENTS AND METHODS: Twenty-three consecutive patients with a total of 41 wounds (1.0-7.5 cm in diameter) were treated with placement of HSE after sharp excisional debridement. All patients with pressure ulcers received alternating air therapy with zero-pressure alternating air mattresses. MAIN OUTCOME MEASURE: Time to 100% healing, as defined by full epithelialization of the wound and by no drainage from the site. RESULTS: Seven of 10 patients with diabetic foot ulcers had complete healing of all wounds. In these patients 17 of 20 wounds healed in an average of 42 days. Seven of 13 patients with pressure ulcers had complete healing of all wounds. In patients with pressure ulcers, 13 of 21 wounds healed in an average of 29 days. All wounds that did not heal in this series occurred in patients who had an additional stage IV ulcer or a wound with exposed bone. Twenty-nine of 30 wounds that healed did so after a single application of the HSE. CONCLUSIONS: In diabetic ulcers and pressure ulcers of various durations, the application of HSE with the surgical principles used in a traditional skin graft is successful in producing healing. The high success rate with complete closure in these various types of wounds suggests that HSE may function as a reservoir of growth factors that also stimulate wound contraction and epithelialization. If a wound has not fully healed after 6 weeks, a second application of HSE should be used. If the wound is not healing, an occult infection is the likely cause. All nonischemic diabetic foot and pressure ulcers that are identified and treated early with aggressive therapy (including antibiotics, off-loading of pressure, and biological therapy) will not progress.     

The Use of Negative Pressure Wound Therapy for Random Local Flaps at the Ankle Region

Local random flaps are seldom used for reconstruction of complex ankle wounds because of concern for flap failure attributable to vascular compromise and tissue edema. Negative pressure wound therapy has been shown to improve perfusion and limit tissue edema. The objective of this study was to demonstrate the utility of negative pressure wound therapy in improving outcomes for local flaps of the ankle. Ten consecutive patients presenting with complex ankle wounds and reconstructed using local flaps were treated with negative pressure wound therapy postoperatively. Type of flap, immediate and long-term outcomes, and complications were assessed. Seventeen local flaps were performed on 10 patients to reconstruct their ankle wounds. Mean follow up was 88 days. All flaps healed without tissue compromise or necrosis. Only one partial dehiscence and no infections were observed. This study demonstrates that negative pressure therapy may contribute to the viability of random local flaps by decreasing venous congestion. Our experience using negative pressure wound therapy on local flaps suggests that it may serve as a useful adjunct to ensure successful closure of high-risk wounds.     

Vacuum assisted closure (VAC)/negative pressure wound therapy (NPWT) for difficult wounds: A review

Delayed wound healing particularly in difficult wounds and in elderly with co morbidities is a major concern. It leads to the pain, morbidity, prolonged treatment, and require major reconstructive surgery which imposes enormous social and financial burden. Vacuum-assisted closure (VAC) is an alternative method of wound management, which uses the negative pressure to prepare the wound for spontaneous healing or by lesser reconstructive options. Method of VAC application includes thorough debridement, adequate haemostasis and application of sterile foams dressing. A fenestrated tube is embedded in the foam and wound is sealed with adhesive tape to make it air tight. The fenestrate tube is connected to a vacuum pump with fluid collection container. The machine delivers continuous or intermittent suction, ranging from 50 to 125 mmHg. The VAC dressings are changed on 3rd day. Negative pressure therapy stabilizes the wound environment, reduces wound edema/bacterial load, improves tissue perfusion, and stimulates granulation tissue and angiogenesis. All this improves the possibility of primary closure of wounds and reduce the need for plastic procedures. VAC therapy appears to be a simple and more effective than conventional dressings for the management of difficult wound in terms of reduction in wound volume, depth, treatment duration and cost.     

Initial multi‐centre observations upon the effect of a new topical negative pressure device upon patient and clinician experience and the treatment of wounds

Topical Negative Pressure (TNP) has become an accepted intervention in wound healing with a growing body of scientific literature supporting the effectiveness of TNP across a wide variety of wound aetiologies. The range of TNP devices has also increased with perhaps the primary distinction being between those TNP devices that employ gauze or foam as a wound dressing. This study reports preliminary multi‐centre observations upon the use of a new gauze based TNP device in the treatment of wounds. Across 3 study centres twenty‐nine subjects were recruited to the study with 8 presenting with leg ulcers, 8 with pressure ulcers, 12 with acute or surgical wounds and 1 with a non‐healing burn injury. Wounds were then treated with the new TNP therapy for a maximum of 17 days (range 2–17 days). There appeared to be a trend for subjects with leg ulcers to be treated for longer (mean duration 12.9 days) compared to subjects with pressure ulcers (mean duration 6.5 days) or those with surgical wounds (mean duration 8.2 days). Given the relatively short duration of the TNP therapy no wound completely healed although 22/29 (75.9%) showed reductions in surface area per day of treatment with all but 1 pressure ulcer and 1 leg ulcer responding positively to treatment. While not an RCT, this and similar cohort studies may be central to the future selection of TNP devices given the increasing importance of the role of the user interface to reduce the likelihood of incorrect use and sub‐optimal outcomes.     

负压封闭引流技术在介入治疗后皮肤坏死软组织缺损中的应用

目的：探讨负压封闭引流技术在介入治疗后皮肤坏死软组织缺损创面的治疗作用。方法：对22例介入治疗后有皮肤软组织缺损坏死的患者采用负压封闭引流装置治疗,并在每次更换负压装置时进行清创。经过15～40天,平均28天的治疗后,部分患者在创面上行二期游离皮片或皮瓣转移修复术。结果：22例患者经过治疗后创面清洁、面积缩小、肉芽生长迅速,16例患者在负压引流治疗后创面直接上皮化愈合,6例患者经过游离皮片移植或皮瓣转移修复后愈合。结论：自制简易负压吸引结合间断清创能够减少创面污染、促进肉芽组织生长、加速创面愈合,还可为二期手术创造条件,缩短术前准备时间,且减轻患者痛苦及医务人员工作量。     

Negative pressure wound therapy as an adjunct in healing of chronic wounds

Negative pressure wound therapy (NPWT) has emerged as a cutting‐edge technology and provides an alternative solution to the problem of wounds. This study was undertaken to assess the efficacy of this technique in the treatment of chronic wounds. A prospective clinical study was used to evaluate our experience in use of NPWT in the healing of pressure ulcers and chronic wounds over 2 years. The primary end point of the study group was the time taken for appearance of healthy granulation tissue and full reepithelialisation without drainage. All patients with sepsis were excluded from the study. The statistical analysis of the data was carried out. Of the 60 patients studied, 41 had associated comorbidities including diabetes mellitus. The commonest site of occurrence was the lower limb. Coverage in the form of a flap was required at presentation in 63·33% of patients. However, after initiation of NPWT, none of them required the procedure and they healed spontaneously either by secondary intention or by skin grafting. The time taken for appearance of healthy granulation tissue was 14·36 ± 4·24 days. Complete healing of wounds occurred by 33·1 ± 10·22 days. There was a statistically significant difference in the volume of the wounds before and after the intervention (P = 0·000). Complications resulting from NPWT were minimal. This technique is an excellent adjunct to surgical debridement.     

Negative pressure wound therapy: an algorithm

Negative pressure wound therapy (NPWT) has overwhelmed the wound-healing world. A systematic review puts it into perspective. The authors have developed an algorithm after careful evaluation and analysis of the scientific literature supporting the use of these devices. This article describes mechanisms of action, technical considerations, wound preparation, and clinical evidence, reviews the literature, and discusses NPWT use in specific wounds, such as diabetic foot ulcers, open abdomen, pressure ulcers, open fractures, sterna wounds, grafts, and flaps. Contraindications for and complications of NPWT are outlined, and specific recommendations given for the situations in which the authors use NPWT.     

Negative pressure wound therapy is associated with up‐regulation of bFGF and ERK1/2 in human diabetic foot wounds

Chronic foot wounds are a leading cause of morbidity and hospitalization for patients with diabetes. Negative pressure wound therapy (NPWT) is known to promote healing of diabetic foot wounds, but the underlying molecular mechanisms remain elusive. We propose to gain molecular insights into the wound healing promoting signals underlying the effects of NPWT on diabetic foot wounds in humans. We assessed 30 patients with diabetic foot ulcers. Of these cases, 15 were treated with NPWT, while 15 patients were treated with traditional gauze therapy. Granulated tissue was harvested before and after treatment in both patient groups and histologically analyzed with hematoxylin & eosin as well as Masson's trichrome staining methods. Immunohistochemistry and Western blot analysis was performed to evaluate expression of basic fibroblast growth factor (bFGF) and extracellular signal‐regulated kinase (ERK)1/2, previously associated with promoting cellular growth and/or wound healing. Unlike controls, the wounds in the NPWT‐treated diabetic patients developed characteristic features of granulated tissue with increased collagen deposition. Immunohistochemical analysis also revealed an increase in bFGF levels in NPWT‐treated patients. Western blot analysis further showed a significant up‐regulation of bFGF and phosphorylated ERK1/2 protein levels in the NPWT‐treated diabetic patients vs. controls. Our studies reveal that NPWT is associated with an up‐regulation of bFGF and ERK1/2 signaling, which may be involved in promoting the NPWT‐mediated wound healing response.     

Ratios of activated matrix metalloproteinase-9 to tissue inhibitor of matrix metalloproteinase-1 in wound fluids are inversely correlated with healing of pressure ulcers

Previous analyses of fluids collected from chronic, nonhealing wounds found elevated levels of inflammatory cytokines, elevated levels of proteinases, and low levels of growth factor activity compared with fluids collected from acute, healing wounds. This led to the general hypothesis that chronic inflammation in acute wounds produces elevated levels of proteinases that destroy essential growth factors, receptors, and extracellular matrix proteins, which ultimately prevent wounds from healing. To test this hypothesis further, pro- and activated matrix metalloproteinases (MMP-2 and MMP-9), tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2), and the ratios of MMPs/TIMPs were assayed in fluids and biopsies collected from 56 patients with chronic pressure ulcers. Specimens included ulcers treated for 0, 10, and 36 days with conventional therapy or with exogenous cytokine therapies. Quantitative assay data were correlated with the amount of healing. The average MMP-9/TIMP-1 ratio in fluids from 56 ulcers decreased significantly as the chronic pressure ulcers healed. Furthermore, the average MMP-9/TIMP-1 ratio was significantly lower for fluids collected on day 0 from wounds that ultimately healed well (> or =85% reduction in initial wound volume) compared with wounds that healed poorly (< 50% wound volume reduction). These data show that the ratio of MMP-9/TIMP-1 levels is a predictor of healing in pressure ulcers and they provide additional support for the hypothesis that high levels of MMP activity and low levels of MMP inhibitor impair wound healing in chronic pressure ulcers.     

Role of negative pressure wound therapy in treating peripheral vascular graft infections

Wound complications involving large subcutaneous vessels can cause significant challenges for surgeons. Negative pressure wound therapy (NPWT) has been increasingly used for treating complex wounds in vascular surgery, including groin infections, either as a bridge to surgical closure or as a primary wound treatment modality. Although a growing body of evidence exists for managing various problematic wounds, such as diabetic foot ulcers and open abdominal wounds, the role of NPWT in wounds involving large blood vessels or wounds complicating infected vascular grafts has not been well defined. A multidisciplinary advisory panel reviewed the literature relevant to wounds related to vascular surgical procedures and complications, focusing on large subcutaneous or infected vascular conduits. The results supported by the literature and the clinical practice of the consensus panel suggested that NPWT can be a useful adjunct to the management of vascular groin infections and dehiscences but must be used with caution.     

再生疗法配合自体微粒皮种植技术的临床应用与分析

目的探讨再生疗法配合自体微粒皮种植技术在治疗面积较大的皮瓣、组织缺损创面的应用、方法及疗效。方法临床上我们遴选了12例患者,其中深度烧伤6例,糖尿病足3例,毒蛇咬伤致严重皮肤软组织坏死2例,静脉血栓致小腿皮肤溃疡1例,分别对上述病例的共16处创面应用再生疗法配合自体微粒皮种植技术进行治疗修复并观察疗效。结果经过应用再生疗法并进行自体微粒皮种植技术治疗后,12例患者创面均愈合,微粒皮种植后创面愈合时间14～37d,愈合后创面基本平整,大部分创面上皮愈合,部分创面瘢痕柔软,无明显增生性瘢痕。关节部位功能不受影响。结论再生疗法配合自体微粒皮种植技术操作简便,手术条件要求相对不高,对患者的二次损伤少,患者依从性高,创面愈合质量好,可以广泛应用于大面积深度烧伤和其他面积较大的各种创疡。     

简易负压封闭引流治疗下肢严重感染性创面的效果观察

目的：探讨自制负压封闭引流装置治疗下肢严重感染性创面的效果.方法：对35例下肢严重感染并有软组织缺损的患者采用自制的封闭式负压吸引装置（由无菌高分子泡沫海绵、手术用无菌贴膜、医用硅胶管、墙壁式负压引流装置组成）治疗,压力-75～-100 mmHg,每48～72 h更换负压装置,并在每次更换负压装置时进行清创.根据创面清洁度及新鲜肉芽生长情况择期行二期游离植皮或皮瓣转移修复术.结果：35例患者经过负压封闭引流10～63 d（平均18 d）治疗后创面清洁,面积较前缩小,肉芽生长新鲜,游离皮片移植或皮瓣转移修复创面均一次性获得成功;且耗材费用（20～50元/次）较进口成套负压封闭引流装置（1000～3000元/次）低廉.结论：自制封闭式负压引流装置结合间断清创能够有效地控制创面感染,促进坏死物脱落,加速愈合,为组织移植、创面修复创造条件;且费用低廉,易于推广.     

Negative pressure wound therapy

Negative pressure wound therapy has become an increasingly important part of wound management. Over the last decade, numerous uses for this method of wound management have been reported, ranging from acute and chronic wounds, to closure of open sternal and abdominal wounds, to assistance with skin grafts. The biophysics behind the success of this treatment largely have focused on increased wound blood flow, increased granulation tissue formation, decreased bacterial counts, and stimulation of wound healing pathways through shear stress mechanisms. The overall success of negative pressure wound therapy has led to a multitude of clinical applications, which are discussed in this article.