Topical negative pressure therapy in wound care

Negative-Pressure Wound Therapy (NPWT) in Horses: A Scoping Review

Obtaining a healthy wound environment that is conductive to healing in horses can be challenging. Negative-pressure wound therapy (NPWT) has been employed in humans to enhance wound healing for decades. The existing evidence for the effectiveness of NPWT remains uncertain in equine medicine. The aim of this review is to investigate NPWT applications and benefits in horses. A scoping review was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines for scoping reviews on three databases (PubMed, Web of Science-Thompson Reuters, and Wiley Online Library). Twenty-four manuscripts were considered. After removing duplicates, 17 papers underwent abstract screening. Of these, 16 + 1 (cited by others) were evaluated for eligibility according to PICOs, including no case reports/retrospective studies, four original articles, and three reviews. Fifteen manuscripts met the inclusion criteria. The focus of the articles was wound management; they included three reports of wounds communicating with synovial structures. Traumatic wounds and surgical-site infections are indications for NPWT. NPWT presents several advantages and few complications making it an attractive alternative to conventional wound management. However, randomized controlled trials should be performed to quantify the benefits and establish precise protocols in horses.

Comparison of the effects of negative pressure wound therapy and negative pressure wound therapy with instillation on wound healing in a porcine model

Background

Negative pressure wound therapy with instillation (NPWTi) is a novel method based on standard negative pressure wound therapy (NPWT). This study aimed to compare the effects of standard NPWT and NPWTi on bioburden and wound healing in a Staphylococcus aureus (S.aureus) infected porcine model.

Methods

Green fluorescent protein-labeled S.aureus infected wounds were created on the back of porcine. Wounds were treated with NPWT or NPWT with instillation (saline). The tissue specimens were harvested on days 0 (12 h after bacterial inoculation), 2, 4, 6, and 8 at the center of wound beds. Viable bacterial counts, laser scanning confocal microscopy, PCR, western blot, and histological analysis were performed to assess virulence and wound healing.

Results

The bacterial count in the NPWTi group was lower than that of the NPWT group and the difference was statistically significant on day 2, day 4, day 6, and day 8 (P < 0.05). The expression levels of agrA, Eap, Spa, and Hla genes of the NPWTi group were significantly lower than that of the NPWT group on day 8 (P < 0.05). The bacterial invasion depth of the NPWTi group was significantly lower than that of the NPWT group on day 2, day 4, day 6, and day 8 (P < 0.05). Though the NPWTi group showed a significantly increased expression of bFGF and VEGF than that of the NPWT group in the early time (P < 0.05), NPWTi cannot lead to better histologic parameters than the NPWT group (P > 0.05).

Conclusion

Our results demonstrated that NPWTi induced a better decrease in bacterial burden and virulence compared with standard NPWT. These advantages did not result in better histologic parameters on the porcine wound model.

Application of Negative Pressure Therapy on Skin Grafts after Soft-Tissue Reconstruction: A Prospective Observational Study

A split-thickness skin graft (STSG) is one of the main tools used in the reconstruction of skin defects. Negative-pressure wound therapy (NPWT) has been widely used as adjunct therapy for wound healing for decades. Few studies have conducted the outcomes of NPWT use as a postoperative dressing for STSGs. This study aimed to compare the outcomes of the application of NPWT versus conventional dressing on STSGs after soft-tissue reconstruction. A prospective observational study was performed at the King Abdullah Medical City. A total of 18 patients with STSGs for acute or chronic skin defects were recruited. Patients from the two groups—10 patients in the NPWT group and 8 in the No-NPWT group—were postoperatively evaluated for three weeks. Assessment included the STSG take rate, wound healing, pain, infection, hematoma formation, and the need to re-graft the same recipient area. Our data demonstrated a higher mean skin graft take rate in the second and third weeks of the No-NPWT group compared to the NPWT group, but it was not statistically significant (p > 0.05). No significant differences between the two groups in terms of wound healing, pain, infection, hematoma formation, and the need to re-graft (p > 0.05) were found. Our study showed that the conventional dressing of STSGs is not inferior to NPWT. In addition, conventional dressing was shown to be easier to use and less expensive to apply, as well as having a higher skin graft take rate and lower infection rate.

A systematic review of ozone therapy for treating chronically refractory wounds and ulcers

This study aims at evaluating the efficacy and safety of ozone therapy for chronic wounds. The Cochrane Library, PubMed, Ovid Embase, Web of Science, and Chinese Biomedical Literature Database were searched. Randomised controlled trials (RCTs) about participants with chronic wounds were included. Risk of bias assessment was performed by the Cochrane risk‐of‐bias tool. A randomised‐effects model was applied to pool results according to the types of wounds or ulcers. Among 12 included studies, ozone was implemented by topical application (ozone gas bath, ozonated oil, ozone water flushing) and systematic applications including autologous blood immunomodulation and rectal insufflation. The results indicated compared with standard control therapy for diabetic foot ulcers, ozone therapy regardless of monotherapy or combined control treatment markedly accelerated the improvement of the wound area(standardised mean difference(SMD) = 66.54%, 95% confidence interval (CI) = [46.18,86.90], P < .00001) and reduced the amputation rate (risk ration (RR) = 0.36, 95% CI = [0.24,0.54], P < .00001). But there is no improvement in the proportion of participants with completely healed wounds and length of hospital stay. No adverse events associated with ozone treatment have been reported. And the efficacy of ozone therapy for other wound types is still uncertain because of no sufficient studies. More high‐quality randomised controlled trials are needed to confirm the efficacy and safety of ozone therapy for chronic wounds or ulcers.

The use of negative pressure wound therapy increases failure rate in debridement and implant retention for acute prosthetic joint infection

BACKGROUND

To date only scanty data exist regarding the effect of failed debridement, antibiotics, irrigation and retention of the prostheses (DAIR) and negative pressure wound therapy (NPWT) on the outcome of a subsequent exchange arthroplasty.

OBJECTIVE

The objective of this study was to determine the success rate of a two- or multi-stage procedure after initial failed DAIR/NPWT in patients with an acute periprosthetic joint infection (PJI) and to evaluate the influence of possible risk factors for treatment failure.

METHODS

Nineteen consecutive patients with a persisting PJI and ongoing NPWT after treatment of an acute PJI with DAIR of the hip or knee joint from October 2010 to June 2017 were included. All patients were treated according to a structured treatment algorithm after referral to our hospital. The endpoint was a successful reimplantation with absence of signs of infection two years after replantation ("replantation group") or treatment failure ("treatment failure group") in terms of a permanent girdlestone arthroplasty, fistula, amputation or death. A risk factor analysis was performed between the two groups.

RESULTS

Explantation was performed in 15 cases, amputation in one case, and DAIR/establishment of a fistula in three cases. The treatment success rate after reimplantation in terms of "definitively free of infection" two years after surgery according to Laffer was 36.85% (seven out of 19 patients). Statistical analysis revealed the number of surgeries until wound consolidation (p= 0.007), number of detected bacterial strains (p= 0.041), a polymicrobial PJI (p= 0.041) and detection of a difficult-to-treat organism (p= 0.005) as factors associated with treatment failure. After failed DAIR/NPWT we could detect a significant higher number of different bacterial strains (p= 0.001).

CONCLUSIONS

The treatment success rate after failed DAIR and NPWT with 36% is low and associated with a high treatment failure rate (permanent girdlestone arthroplasty, fistula or amputation, death). Thus, the definition of risk factors is crucial. We found that the number of revisions until wound consolidation, a polymicrobial PJI and detection of a difficult-to-treat organisms were risk factors for treatment failure. Furthermore, after failed DAIR/NPWT we could detect a significant higher number of different bacterial strains, with a possible adverse effect on a consecutive exchange.

Expanded negative pressure wound therapy in healing diabetic foot ulcers: a prospective randomised study

OBJECTIVE

This study aims to evaluate the benefits of treating diabetic foot ulcers (DFU) through a revised procedure using the mechanisms underlying negative pressure wound therapy (NPWT) in such a way as to achieve reduced and more evenly distributed lateral tension lines across the wound.

METHOD

Patients with type 2 diabetes were assessed for elegibility. Included patients were divided randomly into two groups: the NPWT control group and the NPWT+ group. Patients in the NPWT control group were treated in the traditional manner: wounds were covered with foams shaped to fit the wound precisely. In the NPWT+ group, foams were shaped to fit the wound precisely, and an additional foam was then wrapped around the foot.

RESULTS

Some 85 patients were assessed for eligibility; 59 were randomised into two groups: 29 patients in the NPWT+ group and 30 patients in the NPWT group. The primary objective was median healing time (NPWT+ 19 days, interquartile ratio (IQR) 7.5; NPWT 33 days, IQR 16; p<0.00001), and complete wound healing at three weeks (NPWT+ 55.20% NPWT 26.70% p=0.02). Secondary endpoints included number of major amputations (none in either group) and number of infections (NPWT+ 3.44% of patients, NPWT 6.66% of patients; p=0.57).

CONCLUSION

Our initial findings show that this treatment significantly reduced wound closure times and accelerated healing in DFUs. It also demonstrated promising improvements in healing rates, with no significant increase in wound complications.

Impact of Previous Irradiation on Wound Healing after Negative Pressure Wound Therapy in Head and Neck Cancer Patients-A Systematic Review

(1) Background: Negative pressure wound therapy (NPWT) has been effectively used for wound management in comparison to traditional dressings. The purpose of this study was to provide an evidence-based review of NPWT in head and neck cancer patients, as well as the impact of previous irradiation and other risk factors on wound healing. (2) Material and Methods: We conducted a comprehensive search in PubMed, Medline, Embase, Web of Science, and Cochrane Library databases for relevant literature. (3) Results: 15 studies fulfilled the inclusion criteria. The most common etiologies requiring NPWT were defects post tumor resection and flap reconstruction and oro/pharyngo-cutaneous fistulas. The neck was found to be the most common site of involvement (47.3%). The overall wound healing response rate was 87.5%. The median negative pressure recorded was 125 mm of Hg, with a median dressing change time of three days. Previous irradiation (p = 0.01; OR = 4.07) and diabetes mellitus (DM) (p = 0.001; OR = 5.62) were found to be significantly associated with delayed wound healing after NPWT. (4) Conclusion: NPWT treats complex wounds in head and neck cancer patients and should represent a significant armamentarium in head and neck cancers. Previous irradiation and DM have detrimental effects on wound healing after NPWT.

Prevention of postoperative surgical wound complications in ankle and distal tibia fractures: results of Incisional Negative Pressure Wound Therapy

BACKGROUND AND AIM OF THE WORK

complications in surgical wound healing represent the main postoperative complication in ankle and distal tibia fractures. Whereas the use of Incisional Negative Pressure Wound Therapy (INPWT) is recognized to have a role in wound complications prevention in prosthetic surgery, literature about its use in trauma surgery is scarce. The aim of this study was to compare the effectiveness of INWPT with a conventional dressing in order to prevent surgical wound complications in ankle and distal tibia fractures.

METHODS

The study population included patients over 65 years as well as patients under 65 years considered at risk for wound complications (smokers, obese, affected by diabetes), who underwent ORIF for bi/tri-malleolar ankle fractures or distal tibia (pilon) fractures. After surgery, patients were randomized to receive a conventional dressing or INPWT. Complications in surgical wound healing were classified in major (requiring surgical intervention) and minor complications.

RESULTS

65 patients were included in the study. The rate of minor and major complications between the two groups was not significantly different, although a positive trend towards a lower minor complications rate was noted in the INPWT group (12.6% vs 34.7%). No complications or complaints were reported for the INPWT device.

CONCLUSIONS

INPWT proved to be safe, well-tolerated and showed promising results in preventing surgical wound complications in ankle and distal tibia fractures.

Clinical Experiences with Closed Incisional Negative Pressure Wound Treatment on Various Anatomic Locations

Background

Closed incisional negative pressure wound treatment (ciNPWT) is one of the promising methods for the prevention of complications in surgical incisions. The mechanisms of ciNPWT have previously been elucidated and in this series, we demonstrate various, as of yet, underreported uses for the technology. Our aim is to share our experience with ciNPWT on various anatomic sites with novel indications. 

Materials and methods

ciNPWT was used in 24 patients. The mean age was 49.6. All the incisions were sutured, clean, and non-infected. Patients’ sex, age, comorbidities, anatomic location of the wound, and the indications for ciNPWT were recorded.

Results

The mean number of applications was three per patient. One suture dehiscence after one session of ciNPWT was encountered in a flap donor site of an infant operated for meningomyelocele. Late-term seroma and hematoma formation were encountered in two patients. No surgical site infection, wound dehiscence, and ciNPWT related complications were seen in other patients. The majority of the applications were on the trunk, lower extremity, pelvis, upper extremity, and scalp respectively. Indications for ciNPWT utilization were preventing dehiscence, seroma, and hematoma formation in the majority of the patients.

Conclusion

ciNPWT is reliable and effective in the prevention of post-operative wound dehiscence and surgical site infections. It can be used safely in various locations and different indications for preventingcomplications such as preventing dehiscence in revision surgeries, cerebrospinal fluid (CSF) fistula formation in the scalp, and wound breakdown in chronic corticosteroid use,

Effects of ozone for treating chronically refractory wounds and ulcers: A protocol for systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The prevalence of chronically refractory wounds and ulcers is growing rapidly. However, the treatment options are not completely effective. Ozone has been demonstrated as being useful in promoting wound healing as well as adverse events in individual studies. Consequently, it is necessary to conduct a meta-analysis of high-quality trials to find out whether ozone therapy is effective and safe in these chronic wounds.

METHODS

We will search the Cochrane Library, PubMed, the Web of Science, Embase, CBM, and the Chinese Clinical Registry website without restriction on language, date, or study setting. Randomized controlled trials of ozone therapy for chronical wounds or ulcers will be retrieved in diverse databases from inception to May 2020. The primary outcome of the meta-analysis is the proportion of participants with completely healed wounds; time to achieve complete ulcer healing; change in wound size. The secondary outcomes include the incidence of adverse events, amputation, quality of life, length of hospital stay, and cost. Two reviewers will adopt the Cochrane Collaboration's risk of bias tool to assess the randomized controlled trials and all relevant data will be analyzed by utilizing the Review Manager software V5.3.0.

RESULTS

This study will offer a high-quality synthesis of the effectiveness and safety of ozone for treating chronically refractory wounds and ulcers.

CONCLUSION

This systematic review and meta-analysis will find out the available evidence to assess whether ozone therapy is beneficial to wound healing and side effects, producing evidence reference for clinical practice on the treatment of wound care.

Vibrational stress affects extracellular signal-regulated kinases activation and cytoskeleton structure in human keratinocytes

As the outermost organ, the skin can be damaged following injuries such as wounds and bacterial or viral infections, and such damage should be rapidly restored to defend the body against physical, chemical, and microbial assaults. However, the wound healing process can be delayed or prolonged by health conditions, including diabetes mellitus, venous stasis disease, ischemia, and even stress. In this study, we developed a vibrational cell culture model and investigated the effects of mechanical vibrations on human keratinocytes. The HaCaT cells were exposed to vibrations at a frequency of 45 Hz with accelerations of 0.8g for 2 h per day. The applied mechanical vibration did not affect cell viability or cell proliferation. Cell migratory activity did increase following exposure to vibration, but the change was not statistically significant. The results of immunostaining (F-actin), western blot (ERK1/2), and RT-qPCR (FGF-2, PDGF-B, HB-EGF, TGF-β1, EGFR, and KGFR) analyses demonstrated that the applied vibration resulted in rearrangement of the cytoskeleton, leading to activation of ERK1/2, one of the MAPK signaling pathways, and upregulation of the gene expression levels of HB-EGF and EGFR. The results suggest that mechanical vibration may have wound healing potential and could be used as a mechanical energy-based treatment for enhancing wound healing efficiency.

EWMA Document: Negative Pressure Wound Therapy

1. Introduction Since its introduction in clinical practice in the early 1990's negative pressure wounds therapy (NPWT) has become widely used in the management of complex wounds in both inpatient and outpatient care.¹ NPWT has been described as a effective treatment for wounds of many different aetiologies^2,3 and suggested as a gold standard for treatment of wounds such as open abdominal wounds,^4-6 dehisced sternal wounds following cardiac surgery^7,8 and as a valuable agent in complex non-healing wounds.^9,10 Increasingly, NPWT is being applied in the primary and home-care setting, where it is described as having the potential to improve the efficacy of wound management and help reduce the reliance on hospital-based care.¹¹ While the potential of NPWT is promising and the clinical use of the treatment is widespread, highlevel evidence of its effectiveness and economic benefits remain sparse.^12-14 The ongoing controversy regarding high-level evidence in wound care in general is well known. There is a consensus that clinical practice should be evidence-based, which can be difficult to achieve due to confusion about the value of the various approaches to wound management; however, we have to rely on the best available evidence. The need to review wound strategies and treatments in order to reduce the burden of care in an efficient way is urgent. If patients at risk of delayed wound healing are identified earlier and aggressive interventions are taken before the wound deteriorates and complications occur, both patient morbidity and health-care costs can be significantly reduced. There is further a fundamental confusion over the best way to evaluate the effectiveness of interventions in this complex patient population. This is illustrated by reviews of the value of various treatment strategies for non-healing wounds, which have highlighted methodological inconsistencies in primary research. This situation is confounded by differences in the advice given by regulatory and reimbursement bodies in various countries regarding both study design and the ways in which results are interpreted. In response to this confusion, the European Wound Management Association (EWMA) has been publishing a number of interdisciplinary documents^15-19 with the intention of highlighting: The nature and extent of the problem for wound management: from the clinical perspective as well as that of care givers and the patients Evidence-based practice as an integration of clinical expertise with the best available clinical evidence from systematic research The nature and extent of the problem for wound management: from the policy maker and healthcare system perspectives The controversy regarding the value of various approaches to wound management and care is illustrated by the case of NPWT, synonymous with topical negative pressure or vacuum therapy and cited as branded VAC (vacuum-assisted closure) therapy. This is a mode of therapy used to encourage wound healing. It is used as a primary treatment of chronic wounds, in complex acute wounds and as an adjunct for temporary closure and wound bed preparation preceding surgical procedures such as skin grafts and flap surgery. Aim An increasing number of papers on the effect of NPWT are being published. However, due to the low evidence level the treatment remains controversial from the policy maker and health-care system's points of view-particularly with regard to evidence-based medicine. In response EWMA has established an interdisciplinary working group to describe the present knowledge with regard to NPWT and provide overview of its implications for organisation of care, documentation, communication, patient safety, and health economic aspects. These goals will be achieved by the following: Present the rational and scientific support for each delivered statement Uncover controversies and issues related to the use of NPWT in wound management Implications of implementing NPWT as a treatment strategy in the health-care system Provide information and offer perspectives of NPWT from the viewpoints of health-care staff, policy makers, politicians, industry, patients and hospital administrators who are indirectly or directly involved in wound management.

Spatial-Temporal Changes of Mechanical Microenvironment in Skin Wounds During Negative Pressure Wound Therapy

Cell migration, proliferation, and differentiation are regulated by mechanical cues during skin wound healing. Negative pressure wound therapy (NPWT) reduces the healing period by optimizing the mechanical microenvironment of the wound bed. Under NPWT, it remains elusive how the mechanical microenvironment (e.g., stiffness, strain gradients) changes both in time and space during wound healing. To illustrate this, the healing time of full-thickness skin wounds under NPWT, with pressure settings ranging from -50 to -150 mm Hg, were evaluated and compared with gauze dressing treatments (control group), and three-dimensional finite element models of full-thickness skin wounds on days 1 and 5 after treatment were developed on the basis of MR 3D imaging data. Shear wave elastography (SWE) was applied to detect the stiffness of wound soft tissue on days 1 and 5, and nonlinear finite element analysis (FEA) was used to represent the spatial-temporal environment of the 3D strain field of the wound under NPWT vs the control group. Compared with the control group, NPWT with -50, -80, and -125 mm Hg promoted wound healing. SWE showed that the elastic modulus of wounded skin increased during healing. Meanwhile, the elastic modulus in wounded skin under NPWT was significantly smaller than in the control group. Strain and its gradient decreased under NPWT during wound healing, while no significant change was observed in the control group. This study, which is based on MR 3D imaging, shear wave elastography, and nonlinear FEA, provides an in-depth understanding of changes of the skin mechanical microenvironment under NPWT in the time-space dimension and the associated wound healing.

Study of negative pressure wound therapy as an adjunct treatment for acute burns in children (SONATA in C): protocol for a randomised controlled trial

BACKGROUND

Although negative pressure wound therapy (NPWT) is widely used in the management of several wound types, its efficacy as a primary therapy for acute burns has not yet been adequately investigated, with research in the paediatric population particularly lacking. There is limited evidence, however, that NPWT might benefit children with burns, amongst whom scar formation, wound progression and pain continue to present major management challenges. The purpose of this trial is to determine whether NPWT in conjunction with standard therapy accelerates healing, reduces wound progression and decreases pain more effectively than standard treatment alone.

METHODS/DESIGN

A total of 104 children will be recruited for this trial. To be eligible, candidates must be under 17 years of age and present to the participating children's hospital within 7 days of their injury with a thermal burn covering <5% of their total body surface area. Facial and trivial burns will be excluded. Following a randomised controlled parallel design, participants will be allocated to either an active control or intervention group. The former will receive standard therapy consisting of Acticoat™ and Mepitel™. The intervention arm will be treated with silver-impregnated dressings in addition to NPWT via the RENASYS TOUCH™ vacuum pump. Participants' dressings will be changed every 3 to 5 days until their wounds are fully re-epithelialised. Time to re-epithelialisation will be studied as the primary outcome. Secondary outcomes will include pain, pruritus, wound progression, health-care-resource use (and costs), ease of management, treatment satisfaction and adverse events. Wound fluid collected during NPWT will also be analysed to generate a proteomic profile of the burn microenvironment.

DISCUSSION

The study will be the first randomised controlled trial to explore the clinical effects of NPWT on paediatric burns, with the aim of determining whether the therapy warrants implementation as an adjunct to standard burns management.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, ACTRN12618000256279 . Registered on 16 February 2018.

[Application of VSD in 6 Cases of Postoperative Infection -A Clinical Experience Sharing]

背景与目的

手术切口感染是胸外科术后常见并发症之一，其危害与感染程度、部位等相关，轻者致局部疼痛、住院时间延长、费用增加，重者可导致严重感染，甚至感染性休克、危及生命。因此，妥善处理切口感染，有利于促进恢复、降低疾病负担、奠定进一步治疗良好基础。切口感染传统外科处理措施包括彻底引流、加强换药、使用抗生素等，存在治疗过程长、治疗效果不确切等不足。本研究对我科6例胸部手术术后发生感染患者尝试性使用负压封闭引流装置（vacuum sealing drainage, VSD）的经验进行总结，以期改进传统应对患者胸部手术术后感染的处理模式。

方法

对我院近一年来出现胸部手术术后切口感染或手术切口瘘的患者相关临床数据进行回顾和总结，选择了其中6例使用VSD材料治疗术后感染的患者，对其使用VSD处理的过程和最终临床结果进行总结讨论。

结果

本研究中所有患者在使用VSD后6 h-10 h内发热、伤口渗出症状消失。7天-10天后拔除引流装置，5例患者创面感染情况明显改善，伤口分泌物消失，手术切缘肉芽组织生长良好，二期手术关闭胸腔和皮肤。1例患者感染严重，去除VSD后分泌物仍较多，效果不明显，再次放置VSD装置，7天后去除VSD装置，患者手术切口无渗出，肉芽组织生长良好，二期手术关闭胸腔和皮肤。所有6例患者最终感染症状缓解，症状改善，手术切口愈合良好出院。2例食管癌患者中，平均手术时间427.5 min，术后平均住院天数40天，术后平均换药次数8.5次，住院期间平均总花费111, 893.47元；4例慢性脓胸患者中，平均手术时间192.5 min，术后平均住院天数27.75天，术后平均换药次数5.5次，住院期间平均总花费48, 237.71元。

结论

VSD在处理胸外科手术术后切口感染患者中效果良好，减少了患者的痛苦和负担，保证了发生术后感染患者的生活质量。

Mechanical effects of negative pressure wound therapy on abdominal wounds - effects of different pressures and wound fillers

The mechanical deformation of the wound edge resulting from negative pressure wound therapy (NPWT) at the standard setting of around -120 mmHg has positive effects in promoting wound healing. However, it may cause pain to the patient during treatment. It is therefore important to study the mechanical effects of the wound edges using lower pressure and different wound fillers. Abdominal wounds were created on eight pigs. The wounds were sealed for NPWT using foam or gauze. Negative pressures between -20 and -160 mmHg were applied, and the decrease in wound diameter and the force with which the edges of the wound were drawn together (wound edge force) were measured. Increasing levels of negative pressure resulted in a gradual decrease in wound diameter and increase in wound edge force and reached a maximum at -120 mmHg, which is the pressure commonly used in clinical practice. Both the decrease in wound diameter and the increase in wound edge force was greater with foam than with gauze. A pressure of -80 mmHg has only 15% less effect than -120 mmHg, while a lower pressure (-40 mmHg) diminished the effects on diameter and force markedly. The NPWT-induced decrease in wound diameter and increase in wound edge force are greater at higher levels of negative pressure and when using foam than when using gauze as a wound filler. It may be possible to tailor the type of wound filler and level of negative pressure to obtain the best balance between wound healing and patient comfort.

Handcrafted Vacuum-Assisted Device for Skin Ulcers Treatment Versus Traditional Therapy, Randomized Controlled Trial

BACKGROUND

Chronic lower limb ulcers constitute a public health problem, with important socioeconomic implications and high attention cost. This trial evaluates handcrafted vacuum-assisted therapy versus traditional treatment effectiveness for lower limbs ulcers.

MATERIALS AND METHODS

It was a prospective randomized clinical trial conducted over 144 patients with lower limbs ulcers. Patients were randomized into two groups of 72 patients: Experimental group were treated with debridement, cure and a handcrafted vacuum-assisted device that was changed every 72 h. Control group was treated with debridement and cure with soap every 24 h. Ulcers were evaluated every 72 h and on 10th day. The presence of systemic inflammatory response, pain, granulation tissue and viability for discharge was registered and analyzed .

RESULTS

After exclusion of 18 patients, 126 were included, 65.1% were men with an average of 58 years. Sole region ulcer by diabetic foot was the more frequent in both groups (73%). Leukocytes count, systemic inflammatory response and pain were significantly lower in experimental group (p < 0.05). Discharge criteria and granulation tissue were present earlier in experimental group (p < 0.05).

CONCLUSION

Handcrafted vacuum-assisted system is a feasible and safe method to treat chronic ulcers. This system would benefit patients favoring earlier infection control, faster granulation tissue appearance and earlier discharge. Clinical trials registered in https://www.clinicaltrials.gov/ Number NCT02512159.

Homemade-device-induced negative pressure promotes wound healing more efficiently than VSD-induced positive pressure by regulating inflammation, proliferation and remodeling

Vacuum sealing drainage (VSD) is an effective technique used to promote wound healing. However, recent studies have shown that it exerts positive pressure (PP) rather than negative pressure (NP) on skin. In this study, we created a homemade device that could maintain NP on the wound, and compared the therapeutic effects of VSD-induced PP to those of our homemade device which induced NP on wound healing. The NP induced by our device required less time for wound healing and decreased the wound area more efficiently than the PP induced by VSD. NP and PP both promoted the inflammatory response by upregulating neutrophil infiltration and interleukin (IL)‑1β expression, and downregulating IL‑10 expression. Higher levels of epidermal growth factor (EGF), transforming growth factor (TGF)‑β and platelet-derived growth factor (PDGF), and lower levels of basic fibroblast growth factor (bFGF) were observed in the wound tissue treated with NP compared to the wound tissue exposed to PP. Proliferation in the wound tissue exposed to NP on day 10 was significantly higher than that in wound tissue exposed to PP. NP generated more fibroblasts, keratinized stratified epithelium, and less epithelia with stemness than PP. The levels of ccollagen Ⅰ and Ⅲ were both decreased in both the NP and PP groups. NP induced a statistically significant increase in the expression of fibronectin (FN) on days 3 and 10 compared to PP. Furthermore, the level of matrix metalloproteinase (MMP)‑13 increased in the NP group, but decreased in the PP group on day 3. NP also induced a decrease in the levels of tissue inhibitor of metalloproteinase (TIMP)‑1 and TIMP‑2 during the early stages of wound healing, which was significantly different from the increasing effect of PP on TIMP‑1 and TIMP‑2 levels at the corresponding time points. On the whole, our data indicate that our homemade device which induced NP, was more efficient than VSD‑induced PP on wound healing by regulating inflammation, secretion, proliferation and the distribution of different cells in wound tissue.

Vacuum sealing drainage therapy in the presence of an external fixation device: A case report

RATIONALE

Vacuum sealing drainage (VSD) is widely utilized for treating traumatic wounds.

PATIENT CONCERNS

It is particularly difficult and time consuming to use in combination with an external fixator.

DIAGNOSES

This is because the hardware or pins used for fixation interfere with maintaining a seal, resulting in poor adhesion and subsequent air leakage.

INTERVENTIONS

To resolve this problem, we have devised a new method for sealing the wound dressing, while maintaining the required vacuum.When using this technique, a rubber strip is wrapped around each pin in 3 circles outside the plastic drape, and then tightly tied.

OUTCOMES

After completing this procedure, a vacuum is obtained, and any air leakage stops. We employed this technique to treat a cohort of patients in our department over a period of two years, and obtained good healing of soft tissue without air leakage, as well as good clinical outcomes.

LESSONS

We have observed that patients treated with this method experienced good clinical outcomes without air leakage, and we recommend its use in treating cases where an external fixation device is present.

Evaluation of Vacuum Assisted Closure Therapy for Soft Tissue Injury in Open Musculoskeletal Trauma

INTRODUCTION

The application of controlled levels of negative or sub atmospheric pressure for a prolonged period of time on a wound had shown to accelerate removal of excess fluid and promote hyperaemia, which eventually promote wound healing.

AIM

The study was conducted with the aim to evaluate the effectiveness of Vacuum Assisted Closure (VAC) therapy for soft tissue injury in open musculoskeletal trauma.

MATERIALS AND METHODS

Twenty cases of complex musculoskeletal wound involving different parts of body were included in this progressive randomized study. In patients, aggressive debridement was done before the application of VAC therapy. Controlled negative pressure was uniformly applied to the wound. Dressings were changed after every 4 to 5 days. The evaluation of results included healing rate of the wound, eradication of infection, complication rate, and number of secondary procedures.

RESULTS

VAC therapy over the wound was administered for an average of 20.4 days ±6.72 days (range 14 to 42 days). There was decrease in wound size attained by VAC therapy ranged from 2.6 to 24.4cm(2), with an average reduction of 10.55 cm(2). Three wounds were infected at the start of VAC therapy. However, all patients were cleared of bacterial infection by the end of VAC therapy.

CONCLUSION

VAC therapy using negative pressure promote Wound healing by increasing local capillary perfusion and increased rate of granulation tissue formation, decreases the duration of wound healing and requires fewer painful dressing change.

Mesenchymal stem cell-conditioned medium accelerates wound healing with fewer scars

Mesenchymal stem cells (MSCs) derived from umbilical cords (UC-MSCs) have been shown to enhance cutaneous wound healing by means of the paracrine activity. Fibroblasts are the primary cells involved in wound repair. The paracrine effects of UC-MSCs on dermal fibroblasts have not been fully explored in vitro or in vivo. Dermal fibroblasts were treated with conditioned media from UC-MSCs (UC-MSC-CM). In this model, UC-MSC-CM increased the proliferation and migration of dermal fibroblasts. Moreover, adult dermal fibroblasts transitioned into a phenotype with a low myofibroblast formation capacity, a decreased ratio of transforming growth factor-β1,3 (TGF-β1/3) and an increased ratio of matrix metalloproteinase/tissue inhibitor of metalloproteinases (MMP/TIMP). Additionally, UC-MSC-CM-treated wounds showed accelerated healing with fewer scars compared with control groups. These observations suggest that UC-MSC-CM may be a feasible strategy to promote cutaneous repair and a potential means to realise scarless healing.

Challenges in the Treatment of Chronic Wounds

Significance: Chronic wounds include, but are not limited, to diabetic foot ulcers, venous leg ulcers, and pressure ulcers. They are a challenge to wound care professionals and consume a great deal of healthcare resources around the globe. This review discusses the pathophysiology of complex chronic wounds and the means and modalities currently available to achieve healing in such patients. Recent Advances: Although often difficult to treat, an understanding of the underlying pathophysiology and specific attention toward managing these perturbations can often lead to successful healing. Critical Issues: Overcoming the factors that contribute to delayed healing are key components of a comprehensive approach to wound care and present the primary challenges to the treatment of chronic wounds. When wounds fail to achieve sufficient healing after 4 weeks of standard care, reassessment of underlying pathology and consideration of the need for advanced therapeutic agents should be undertaken. However, selection of an appropriate therapy is often not evidence based. Future Directions: Basic tenets of care need to be routinely followed, and a systematic evaluation of patients and their wounds will also facilitate appropriate care. Underlying pathologies, which result in the failure of these wounds to heal, differ among various types of chronic wounds. A better understanding of the differences between various types of chronic wounds at the molecular and cellular levels should improve our treatment approaches, leading to better healing rates, and facilitate the development of new more effective therapies. More evidence for the efficacy of current and future advanced wound therapies is required for their appropriate use.

Curbing Inflammation in Skin Wound Healing: A Review

Wound healing is a complex regulated process that results in skin scar formation in postnatal mammals. Chronic wounds are major medical problems that can confer devastating consequences. Currently, there are no treatments to prevent scarring. In the early fetus wounds heal without scarring and the healing process is characterized by relatively less inflammation compared to adults; therefore, research aimed at reducing the inflammatory process related to wound healing might speed healing and improve the final scar appearance.

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.

Hyperbaric oxygen therapy for chronic wounds

BACKGROUND

Chronic wounds are common and present a health problem with significant effect on quality of life. Various pathologies may cause tissue breakdown, including poor blood supply resulting in inadequate oxygenation of the wound bed. Hyperbaric oxygen therapy (HBOT) has been suggested to improve oxygen supply to wounds and therefore improve their healing.

OBJECTIVES

To assess the benefits and harms of adjunctive HBOT for treating chronic ulcers of the lower limb.

SEARCH METHODS

For this second update we searched the Cochrane Wounds Group Specialised Register (searched 18 February 2015); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 1); Ovid MEDLINE (1946 to 17 February 2015); Ovid MEDLINE (In-Process & Other Non-Indexed Citations, 17 February 2015); Ovid EMBASE (1974 to 17 February 2015); and EBSCO CINAHL (1982 to 17 February 2015).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the effect on chronic wound healing of therapeutic regimens which include HBOT with those that exclude HBOT (with or without sham therapy).

DATA COLLECTION AND ANALYSIS

Three review authors independently evaluated the risk of bias of the relevant trials using the Cochrane methodology and extracted the data from the included trials. We resolved any disagreement by discussion.

MAIN RESULTS

We included twelve trials (577 participants). Ten trials (531 participants) enrolled people with a diabetic foot ulcer: pooled data of five trials with 205 participants showed an increase in the rate of ulcer healing (risk ratio (RR) 2.35, 95% confidence interval (CI) 1.19 to 4.62; P = 0.01) with HBOT at six weeks but this benefit was not evident at longer-term follow-up at one year. There was no statistically significant difference in major amputation rate (pooled data of five trials with 312 participants, RR 0.36, 95% CI 0.11 to 1.18). One trial (16 participants) considered venous ulcers and reported data at six weeks (wound size reduction) and 18 weeks (wound size reduction and number of ulcers healed) and suggested a significant benefit of HBOT in terms of reduction in ulcer area only at six weeks (mean difference (MD) 33.00%, 95% CI 18.97 to 47.03, P < 0.00001). We identified one trial (30 participants) which enrolled patients with non-healing diabetic ulcers as well as venous ulcers ("mixed ulcers types") and patients were treated for 30 days. For this "mixed ulcers" there was a significant benefit of HBOT in terms of reduction in ulcer area at the end of treatment (30 days) (MD 61.88%, 95% CI 41.91 to 81.85, P < 0.00001). We did not identify any trials that considered arterial and pressure ulcers.

AUTHORS' CONCLUSIONS

In people with foot ulcers due to diabetes, HBOT significantly improved the ulcers healed in the short term but not the long term and the trials had various flaws in design and/or reporting that means we are not confident in the results. More trials are needed to properly evaluate HBOT in people with chronic wounds; these trials must be adequately powered and designed to minimise all kinds of bias.

A portable, disposable system for negative-pressure wound therapy

Negative-pressure wound therapy (NPWT) imparts a number of clinical effects that promote a healing response and, as such, is a well-established means of treating a variety of wound types. Historically, the technique has been primarily used in the hospital setting; however, the introduction of more portable devices has led to an increase in the use of NPWT in the homecare setting, thereby facilitating early discharge of patients from hospital and continuity of care in the community. Portable NPWT devices also have the potential to impact positively on patients' quality of life, allowing increased mobility and freedom to undertake normal activities of daily living. Following the development of its standard Avance® NPWT system and associated dressing kits, Mölnlycke Health Care (Gothenburg, Sweden) has introduced a single-patient-use, disposable NPWT system; Avance Solo. This has been developed with a view to maximising patient freedom and mobility, providing a single-patient-use NPWT solution for multi-week treatment to allow quick and easy discharge of patients from hospital to home, and reducing some of the challenges of logistics and administration associated with the provision of NPWT for the caregiver. As with the standard NPWT system, the single-patient use system is supplied with a number of products incorporating Safetac® adhesive technology to minimise the risk of patients suffering unnecessary pain and trauma associated with dressing changes. This article presents a series of case studies describing procedures and outcomes following the application of the Avance Solo single-patient-use system.

Negative pressure wound therapy for partial-thickness burns

BACKGROUND

A burn wound is a complex and evolving injury, with both local and systemic consequences. Burn treatments include a variety of dressings, as well as newer strategies, such as negative pressure wound therapy (NPWT), which, by means of a suction force that drains excess fluids from the burn, tries to promote the wound healing process and minimise progression of the burn wound.

OBJECTIVES

To assess the effectiveness of NPWT for people with partial-thickness burns.

SEARCH METHODS

We searched the Cochrane Wounds Group Specialised Register (searched 04 September 2014); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 8).

SELECTION CRITERIA

All randomised controlled trials (RCTs) and controlled clinical trials (CCTs) that evaluated the safety and effectiveness of NPWT for partial-thickness burns.

DATA COLLECTION AND ANALYSIS

Two review authors used standardised forms, and extracted the data independently. We assessed each trial for risk of bias, and resolved differences by discussion.

MAIN RESULTS

One RCT, that was an interim report, satisfied the inclusion criteria. We undertook a narrative synthesis of results, as the absence of data and poor reporting precluded us from carrying out any formal statistical analysis. The trial was at high risk of bias.

AUTHORS' CONCLUSIONS

There was not enough evidence available to permit any conclusions to be drawn regarding the use of NPWT for treatment of partial-thickness burn wounds.

A comparison of primary and delayed wound closure in severe open tibial fractures initially treated with internal fixation and vacuum-assisted wound coverage: a case-controlled study

The ideal timing of wound closure for open tibial fractures is debatable. This study aimed to compare outcomes of primary and delayed wound closure in severe open tibial fractures initially treated with internal fixation and vacuum-assisted wound coverage (VAC). Data of 80 patients with Gustilo-Anderson type IIIA and IIIB open tibial fractures treated with primary internal fixation, VAC, either primary wound closure (PWC) or delayed wound closure (DWC), and external fixation were reviewed retrospectively, and outcomes and complications compared. Patients were divided into three groups, including a PWC group (n = 27), DWC group (n = 22), and a control group (n = 31) that had received external fixation. Among all patients, the median age was 38 years (IRQ 32-47 years), and 67.5% were male. Injuries included 33 Gustilo-Anderson type IIIA and 47 type IIIB. Among injuries, 83% (66/80) were high-energy trauma, 63.8% were contaminated and median injury severity score (ISS) was 14 points. Significant differences were found between groups in fixation methods (p < 0.001). No significant differences were observed between groups in rates of deep infection, osteomyelitis, amputation and nonunion at 6 and 12 months (all p > 0.05), although all rates were markedly lower in the PWC group. The outcomes of PWC performed in conjunction with primary internal fixation and VAC for the treatment of Gustilo-Andersen type IIIA and IIIB open tibial fractures are similar to or better than those of DWC with primary internal fixation and VAC.

Measurement of vancomycin hydrochloride concentration in the exudate from wounds receiving negative pressure wound therapy: a pilot study

It has been reported that negative pressure wound therapy (NPWT) is effective in the treatment of contaminated wounds. We hypothesised that systemically administered antibiotics migrate to wound site effectively by NPWT, which provides the antibacterial effect. We measured and compared the concentrations of vancomycin in the exudate and blood serum. Eight patients with skin ulcers or skin defect wounds who were treated with NPWT and were administered an intravenous drip of vancomycin were enrolled in this study. The wound surfaces were muscle, muscle fascia or adipose tissue. We administered vancomycin intravenously to NPWT patients (1-3 g/day). The exudate was obtained using 500 ml V.A.C. ATS canisters without gel. Three days later, the concentrations of vancomycin were measured. The mean concentration of vancomycin in the exudate from NPWT was 67% of the serum vancomycin concentration. We found that concentrations of vancomycin in NPWT exudates are higher than the previously reported concentrations in soft tissue without NPWT. The proactive use of NPWT might be considered in cases of suspected wound contamination when a systemic antibiotic is administered.

Negative pressure therapy for post-sternotomy wound infections in young children

OBJECTIVES

Post-sternotomy wound infection remains a significant morbidity in congenital and paediatric cardiac surgery. However, the techniques used for this complication in children are not optimal in terms of mortality, morbidity and the use of medical resources. Negative pressure therapy is an effective modality in the treatment in adults, but reports of its use in children are limited. This study evaluated the use of negative pressure therapy in young children for post-sternotomy wound infections.

METHODS

From October 2004 to June 2012, 15 consecutive cases of post-sternotomy wound infections in patients ≤6 years of age were managed with negative pressure therapy, and these patients were followed up for ≥12 months after wound closure. The median Aristotle comprehensive complexity score was 9.9 ± 4.0. The infection was identified at a median of 16 days after surgery, and the procedure was performed within 24 h of diagnosis. No additional surgical procedures were applied.

RESULTS

No cases of hospital mortality or second surgery for infection control occurred. The median duration until wound closure was 25 days (range: 5-92 days). Further, no patient showed sternal instability at treatment termination. During the mean follow-up period of 45.8 ± 31.3 months after wound closure, no admission occurred for infection recurrence. According to a multivariable analysis, the infection depth and patient weight significantly lengthened treatment duration (P = 0.008 and 0.046, respectively).

CONCLUSIONS

Negative pressure therapy is an effective treatment modality for wound infections in paediatric cardiac surgery and results in low morbidity, mortality and medical resource use.

Simultaneous irrigation and negative pressure wound therapy enhances wound healing and reduces wound bioburden in a porcine model

Infected foot wounds are one of the most common reasons for hospitalization and amputation among persons with diabetes. The objective of the study was to investigate a new wound therapy system that employs negative pressure wound therapy (NPWT) with simultaneous irrigation therapy. For this study, we used a porcine model with full-thickness excisional wounds, inoculated with Pseudomonas aeruginosa. Wounds were treated for 21 days of therapy with either NPWT, NPWT with simultaneous irrigation therapy using normal saline or polyhexanide biguanide (PHMB) at low or high flow rates, or control. Data show that NPWT with either irrigation condition improved wound healing rates over control-treated wounds, yet did not differ from NPWT alone. NPWT improved bioburden over control-treated wounds. NPWT with simultaneous irrigation further reduced bioburden over control and NPWT-treated wounds; however, flow rate did not affect these outcomes. Together, these data show that NPWT with simultaneous irrigation therapy with either normal saline or PHMB has a positive effect on bioburden in a porcine model, which may translate clinically to improved wound healing outcomes.

Vacuum assisted closure in the management of wound healing disorders in the head and neck: a retrospective analysis of 23 cases

BACKGROUND

Since the middle of the 1990s vacuum-assisted closure (VAC) has been used in many areas of surgery to manage complex wounds and impaired wound healing. Until recently, little attention has been paid to this treatment modality in the field of head and neck surgery. The evaluation of its efficacy in wound healing disorders of the head and neck was the aim of this study.

MATERIAL AND METHODS

Patients with complex wounds and impaired healing treated with VAC therapy between 2008 and 2011 were included into the study. VAC dressings were changed every 3 days and improvements in wound healing were documented.

RESULTS

23 patients were treated with VAC therapy, in 18 cases (78%) closure of the defect could be reached without any further surgical procedure. 5 patients needed subsequent regional flap reconstruction to close the remaining defect. All of these patients had undergone salvage surgery in a previously irradiated neck before.

CONCLUSION

Vacuum assisted closure is an effective treatment in the management of wound healing disorders and complex wounds in the head and neck. It offers a useful, non-invasive modality to close even large defects in the area. Previous irradiation seems to have a significant negative influence on the outcome of the therapy, but more data are required to assess these effects.

Negative pressure wound therapy for partial-thickness burns

BACKGROUND

A burn wound is a complex and evolving injury, with both local and systemic consequences. Burn treatments include a variety of dressings, as well as newer strategies, such as negative pressure wound therapy (NPWT), which, by means of a suction force that drains excess fluids from the burn, tries to promote the wound healing process and minimise progression of the burn wound.

OBJECTIVES

To assess the effectiveness of NPWT for people with partial-thickness burns.

SEARCH METHODS

For this third update we searched the Cochrane Wounds Group Specialised Register (searched 18 May 2012); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 5); Ovid MEDLINE (2010 to May Week 2 2012); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 17 May 2012); Ovid EMBASE (2010 to 2012 Week 19); and EBSCO CINAHL (2010 to 16 May 2012).

SELECTION CRITERIA

All randomised controlled trials (RCTs) and controlled clinical trials (CCTs) that evaluated the safety and effectiveness of NPWT for partial-thickness burns.

DATA COLLECTION AND ANALYSIS

Two review authors used standardised forms, and extracted the data independently. We assessed each trial for risk of bias, and resolved differences by discussion.

MAIN RESULTS

One RCT, that was an interim report, satisfied the inclusion criteria. We undertook a narrative synthesis of results, as the absence of data and poor reporting precluded us from carrying out any formal statistical analysis. The trial was at high risk of bias.

AUTHORS' CONCLUSIONS

There was not enough evidence available to permit any conclusions to be drawn regarding the use of NPWT for treatment of partial-thickness burn wounds.

A retrospective cohort study evaluating efficacy in high-risk patients with chronic lower extremity ulcers treated with negative pressure wound therapy

The purpose of this study was to evaluate the efficacy of negative pressure wound therapy (NPWT) compared with standard of care on wound healing in high-risk patients with multiple significant comorbidities and chronic lower extremity ulcers (LEUs) across the continuum of care settings. A retrospective cohort study of 'real-world' high-risk patients was conducted using Boston University Medical Center electronic medical records, along with chart abstraction to capture detailed medical history, comorbidities, healing outcomes and ulcer characteristics. A total of 342 patients, 171 NPWT patients with LEUs were matched with 171 non-NPWT patients with respect to age and gender, were included in this cohort from 2002 to 2010. The hazard ratios (HRs) were estimated by COX proportional hazard models after adjusting for potential confounders. The NPWT patients were 2·63 times (95% CI = 1·87-3·70) more likely to achieve wound closure compared with non-NPWT patients. Moreover, incidence of wound closure in NPWT patients were increased in diabetic ulcers (HR = 3·26, 95% CI = 2·21-4·83), arterial ulcers (HR = 2·27, CI = 1·56-3·78) and venous ulcers (HR = 6·31, 95% CI = 1·49-26·6) compared with non-NPWT patients. In addition, wound healing appeared to be positively affected by the timing of NPWT application. Compared with later NPWT users (1 year or later after ulcer onset), early NPWT users (within 3 months after ulcer onset) and intermediate NPWT users (4-12 months after ulcer onset) were 3·38 and 2·18 times more likely to achieve wound healing, respectively. This study showed that despite the greater significant comorbidities, patients receiving NPWT healed faster. Early use of NPWT demonstrated better healing. The longer the interval before intervention is with NPWT, the higher the correlation is with poor outcome.

A pilot study exploring quality of life experienced by patients undergoing negative-pressure wound therapy as part of their wound care treatment compared to patients receiving standard wound care

The use of negative pressure wound therapy (NPWT) has been widely documented as a technique to help heal complex wounds. This article presents the findings of a preliminary study which aimed to explore quality of life (QoL) experienced by patients undergoing NPWT as part of their wound care treatment in comparison to that of patients with a wound using traditional (standard) wound care therapies. A quasi-experimental study was undertaken, with patients treated in wound care/vascular clinics with chronic/acute wounds. QoL impact was measured using the Cardiff Wound Impact Schedule and administered post-consent at timed intervals. Our results identified that there were no real differences in QoL scores recorded by patients over the 12-week period. Although there was no overall interaction between the therapies used for wound healing, NPWT did have an effect on social life: during the first 2 weeks of the application of therapy, patients in the NPWT group reported an increase in the social life domain. The authors conclude that true QoL can only be elicited if an accurate baseline is established or if data is collected over a long enough period to allow comparison of scores over time.

Hyperbaric oxygen therapy for chronic wounds

BACKGROUND

Chronic wounds are common and present a health problem with significant effect on quality of life. Various pathologies may cause tissue breakdown, including poor blood supply resulting in inadequate oxygenation of the wound bed. Hyperbaric oxygen therapy (HBOT) has been suggested to improve oxygen supply to wounds and therefore improve their healing.

OBJECTIVES

To assess the benefits and harms of adjunctive HBOT for treating chronic ulcers of the lower limb.

SEARCH METHODS

For this first update we searched the Cochrane Wounds Group Specialised Register (searched 12 January 2012); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 4); Ovid MEDLINE (1950 to January Week 1 2012); Ovid MEDLINE (In-Process & Other Non-Indexed Citations, 11 July 2012); Ovid EMBASE (1980 to 2012 Week 01); and EBSCO CINAHL (1982 to 6 January 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the effect on chronic wound healing of therapeutic regimens which include HBOT with those that exclude HBOT (with or without sham therapy).

DATA COLLECTION AND ANALYSIS

Three review authors independently evaluated the risk of bias of the relevant trials using the Cochrane methodology and extracted the data from the included trials. We resolved any disagreement by discussion.

MAIN RESULTS

We included nine trials (471 participants). Eight trials (455 participants) enrolled people with a diabetic foot ulcer: pooled data of three trials with 140 participants showed an increase in the rate of ulcer healing (risk ratio (RR) 5.20, 95% confidence interval (CI) 1.25 to 21.66; P = 0.02) with HBOT at six weeks but this benefit was not evident at longer-term follow-up at one year. There was no statistically significant difference in major amputation rate (pooled data of five trials with 312 participants, RR 0.36, 95% CI 0.11 to 1.18). One trial (16 participants) considered venous ulcers and reported data at six weeks (wound size reduction) and 18 weeks (wound size reduction and number of ulcers healed) and suggested a significant benefit of HBOT in terms of reduction in ulcer area only at six weeks (mean difference (MD) 33.00%, 95% CI 18.97 to 47.03, P < 0.00001). We did not identify any trials that considered arterial and pressure ulcers.

AUTHORS' CONCLUSIONS

In people with foot ulcers due to diabetes, HBOT significantly improved the ulcers healed in the short term but not the long term and the trials had various flaws in design and/or reporting that means we are not confident in the results. More trials are needed to properly evaluate HBOT in people with chronic wounds; these trials must be adequately powered and designed to minimise all kinds of bias.

Clinical evaluation of gauze-based negative pressure wound therapy in challenging wounds

The aim of this randomised clinical study was to evaluate the effectiveness and safety of gauze-based negative pressure wound therapy (NPWT) in patients with challenging wounds. A total of 50 consecutive patients who had wound drainage for more than 5 days, required open wound management and had existence of culture positive infection were included the study. In this study, gauze-based NPWT was compared with conventional dressing therapy in the treatment of patients with difficult-to-heal wounds. The patients were randomly divided into two groups. Group I (n = 25) was followed by conventional antiseptic (polyhexanide solution) dressings, and group II (n = 25) was treated with saline-soaked antibacterial gauze-based NPWT. The wounds' sizes, number of debridement, bacteriology and recurrence were compared between group I and group II. The mean age of the patients was 59·50 years (range 23-97). In group I, average wound sizes of pre- and post-treatment periods were 50·60 ± 55·35 and 42·50 ± 47·92 cm(2), respectively (P < 0·001). Average duration of treatment was 25·52 ± 16·99 days, and average wound size reduction following the treatment was 19·99% in this group. In group II, the wounds displayed considerable shrinkage, accelerated granulation tissue formation, decreased and cleared away exudate. The average wound sizes in the pre- and post-treatment periods were 98·44 ± 100·88 and 72·08 ± 75·78 cm(2) , respectively (P < 0·001). Average duration of treatment was 11·96 ± 2·48 days, and average wound size reduction following the treatment was 32·34%. The patients treated with antibacterial gauze-based NPWT had a significantly reduced recurrence (2 wounds versus 14 wounds, P = 0·001), and increased number of the culture-negative cases (22 wounds versus 16 wounds, P < 0·047) in a follow-up period of 12 months. There was a statistically significant difference between two groups in all measurements. As a result, we can say that the gauze-based NPWT is a safe and effective method in the treatment of challenging infective wounds when compared with conventional wound management.

Treatment of pelvic defect and infection with endoprosthesis exposure by topical negative pressure and irrigation with myocutaneous flap

The treatment of wound complications and deep infection after hemipelvectomy is challenging. We describe a 17-year-old woman with Ewing sarcoma in the pelvis who underwent hemipelvectomy and reconstruction with an artificial hip joint and bone cement. After the operation, skin necrosis and deep infection with methicillin-resistant Staphylococcus aureus (MRSA) were observed. Debridement resulted in exposure of the artificial joint and bone cement. Topical negative pressure (TNP) and irrigation successfully eradicated the infection. The skin and soft-tissue defect was subsequently reconstructed using a combination of free latissimus dorsi myocutaneous flap and serratus anterior muscle flap. To our knowledge, this is the first described case of combined TNP and irrigation with myocutaneous flap for the treatment of pelvic infection and skin and soft-tissue defect with endoprosthesis exposure.

A clinical review of infected wound treatment with Vacuum Assisted Closure (V.A.C.) therapy: experience and case series

Over the last decade Vacuum Assisted Closure((R)) (KCI Licensing, Inc., San Antonio, TX) has been established as an effective wound care modality for managing complex acute and chronic wounds. The therapy has been widely adopted by many institutions to treat a variety of wound types. Increasingly, the therapy is being used to manage infected and critically colonized, difficult-to-treat wounds. This growing interest coupled with practitioner uncertainty in using the therapy in the presence of infection prompted the convening of an interprofessional expert advisory panel to determine appropriate use of the different modalities of negative pressure wound therapy (NPWT) as delivered by V.A.C.((R)) Therapy and V.A.C. Instill((R)) with either GranuFoam() or GranuFoam Silver() Dressings. The panel reviewed infected wound treatment methods within the context of evidence-based medicine coupled with experiential insight using V.A.C.((R)) Therapy Systems to manage a variety of infected wounds. The primary objectives of the panel were 1) to exchange state-of-practice evidence, 2) to review and evaluate the strength of existing data, and 3) to develop practice recommendations based on published evidence and clinical experience regarding use of the V.A.C.((R)) Therapy Systems in infected wounds. These recommendations are meant to identify which infected wounds will benefit from the most appropriate V.A.C.((R)) Therapy System modality and provide an infected wound treatment algorithm that may lead to a better understanding of optimal treatment strategies.

The influence of low and high pressure levels during negative-pressure wound therapy on wound contraction and fluid evacuation

BACKGROUND

Negative-pressure wound therapy promotes healing by drainage of excessive fluid and debris and by mechanical deformation of the wound. The most commonly used negative pressure, -125 mmHg, may cause pain and ischemia, and the pressure often needs to be reduced. The aim of the present study was to examine wound contraction and fluid removal at different levels of negative pressure.

METHODS

Peripheral wounds were created in 70-kg pigs. The immediate effects of negative-pressure wound therapy (-10 to -175 mmHg) on wound contraction and fluid removal were studied in eight pigs. The long-term effects on wound contraction were studied in eight additional pigs during 72 hours of negative-pressure wound therapy at -75 mmHg.

RESULTS

Wound contraction and fluid removal increased gradually with increasing levels of negative pressure until reaching a steady state. Maximum wound contraction was observed at -75 mmHg. When negative-pressure wound therapy was discontinued, after 72 hours of therapy, the wound surface area was smaller than before therapy. Maximum wound fluid removal was observed at -125 mmHg.

CONCLUSIONS

Negative-pressure wound therapy facilitates drainage of wound fluid and exudates and results in mechanical deformation of the wound edge tissue, which is known to stimulate granulation tissue formation. Maximum wound contraction is achieved already at -75 mmHg, and this may be a suitable pressure for most wounds. In wounds with large volumes of exudate, higher pressure levels may be needed for the initial treatment period.

The clinical efficacy of the vacuum-assisted closure therapy in the management of adult osteomyelitis

INTRODUCTION

Vacuum-assisted closure (VAC) therapy is a sophisticated development of a standard surgical procedure. The purpose of this study is to evaluate the clinical efficacy of managing adult osteomyelitis with VAC therapy.

MATERIALS AND METHODS

We included a total of 68 patients that developed osteomyelitis with Cierny-Mader types 2, 3 and 4, and required open wound management between March 2005 and February 2009. In this study, 35 of these patients were treated by VAC therapy and the other 33 by conventional wound management. The patients were well compared with type, debridement times, wounds coverage, bacteriology and recurrence.

RESULTS

Of the study, the patients treated by VAC therapy had a significantly reduced recurrence (1 vs. 7 wounds, P < 0.05), decreased rate of further autodermoplasty or flap surgery (17 vs. 26 wounds, P < 0.05), and increased cases of bacterial species cultures to negative (29 vs. 15 wounds, P < 0.05), debridement times and type were similar between the two groups.

CONCLUSION

VAC therapy represents a good clinical efficacy in treating osteomyelitis; it can promote the granulation tissue formation, bacterial clearance, and reduce the needs for tissue transfer and muscle flaps in patients. In addition, it could be used as an adjuvant for the eradication of osteomyelitis and improving soft-tissue management, it may be more suitable for treating osteomyelitis with soft-tissue problems.

Influence on pressure transduction when using different drainage techniques and wound fillers (foam and gauze) for negative pressure wound therapy

Pressure transduction to the wound bed in negative pressure wound therapy (NPWT) is crucial in stimulating the biological effects ultimately resulting in wound healing. In clinical practice, either foam or gauze is used as wound filler. Furthermore, two different drainage techniques are frequently employed. One involves the connection of a non-perforated drainage tube to the top of the dressing, while the other involves the insertion of perforated drains into the dressing. The aim of this study was to examine the efficacy of these two different wound fillers and drainage systems on pressure transduction to the wound bed in a challenging wound (the sternotomy wound). Six pigs underwent median sternotomy. The wound was sealed for NPWT using different wound fillers (foam or gauze) and drainage techniques (see earlier). Pressures between 0 and -175 mmHg were applied and the pressure in the wound was measured using saline-filled catheters sutured to the bottom of the wound (over the anterior surface of the heart) and to the side of the wound (on the thoracic wall). The negative pressure on the wound bed increased linearly with the negative pressure delivered by the vacuum source. In a dry wound, the pressure transduction was similar when using the different wound fillers (foam and gauze) and drainage techniques. In a wet wound, pressure transduction was better when using a perforated drainage tube inserted into the wound filler than a non-perforated drainage tube connected to the top of the dressing (-116 ± 1 versus -73 ± 4 mmHg in the wound at a delivered pressure of -125 mmHg for foam, P < 0·01), regardless of the type of wound filler. Gauze and foam are equally effective at delivering negative pressure to the wound bed. Perforated drainage tubes inserted into the wound filler are more efficient than a non-perforated drainage tubes connected to the top of the dressing. The choice of drainage technique may be particularly important in wounds with a large volume of exudate.

Subcutaneous emphysema, muscular necrosis, and necrotizing fasciitis: an unusual presentation of perforated sigmoid diverticulitis

With advancing age and the affluent, low-fiber Western diet, the incidence of diverticular disease is increasing. Fortunately, most cases can be managed conservatively without resorting to surgical intervention. Life-threatening complications such as perforation, especially when it is associated with gross fecal contamination, requires urgent aggressive surgical intervention. A 75-year-old man with absolute constipation and pain in the left iliac fossa underwent urgent laparotomy following fluid and antibiotic resuscitation. A posterior perforated sigmoid diverticulitis associated with myofascial necrosis and generalized pelvic emphysema was identified. In cases where perforation occurs posteriorly and the only external manifestation is surgical emphysema, the outcome is generally favorable.