Modern wound care for the poor: a randomized clinical trial comparing the vacuum system with conventional saline-soaked gauze dressings. Am J Surg. 2010;199:14-20. [PMID: 19362288 DOI: 10.1016/j.amjsurg.2008.12.029]

The Association of Organizational, Environmental, and Staffing Characteristics of Residential Care Facilities and the Risk Rating of Statutory Notifications: A Cross-Sectional Study in Ireland

OBJECTIVES

Safety incidents (SIs) are an indicator of quality in health and social care services. Safety incident research has largely focused on acute health care settings. We aimed to examine the association of organizational, environmental, and staffing characteristics of residential care facilities (RCFs) and severity of regulatory SI notifications.

METHODS

This was a retrospective analysis of SI notifications to the regulator for social care in Ireland received in 2018 and 2019. The mean risk rating of SI notifications for each RCF was used as the outcome. Regression analysis was conducted for the association of RCF characteristics (beds, staff to bed ratio, staff full-time equivalent (FTE), nurse to bed ratio, nurse FTE, number of RCF operated by the service provider, non-statutory or statutory provider) and the outcome, separately for nursing homes and residential disability services.

RESULTS

A total of 53,268 SI notifications were received. One thousand nine hundred RCFs were operational during the period: 594 (31.3%) for RCF-Nursing home and 1304 (68.7%) for RCF-Disability. For nursing homes, in the most adjusted model, the number of RCF operated by a provider ( β coefficient [95% confidence interval] = 0.508 [0.223-0.793]) was positively associated with mean risk rating of SI. For disability services, the following characteristics were positively associated in the most adjusted model: beds (0.081; 0.060-0.101), staff to bed ratio (0.068; 0.017-0.120), nurse to bed ratio (0.356; 0.044-0.667), staff FTE (0.029; 0.015-0.042), and number of RCF operated by a provider (0.067; 0.050-0.084).

CONCLUSIONS

Various modifiable organizational, environmental, and staffing characteristics and severity of SI notifications were associated in this study, most of which were related to RCF-Disability. Policymakers and providers of social care services should be cognizant of the relationship of these characteristics and severity of SI, when designing and planning residential care.

Negative-Pressure Wound Therapy for the Management of Complex Surgical Wounds in a Minority Population

Introduction Negative-pressure wound therapy (NPWT) has been used for decades as an established treatment modality for complex wounds, now commonplace in hospitals and various clinical and outpatient settings. Several studies have noted improved healing outcomes with this device, but the current state of literature is in debate on both clinical and economic effectiveness. The use of NPWT can become expensive, largely because of the complexity of wounds and the need for outpatient management, from which a majority of the benefit is derived. This creates a disparity in access to this therapy. A lack of insurance and limited access to healthcare that is present in minority populations contribute to this inequality. Methods We reviewed the clinical courses of eight patients who were treated with NPWT at a single acute care facility in an underserved area caring for a minority population. Results We describe several different anatomic wounds along with details including the size of wounds, number of debridements, length of hospital stay, duration of treatment, and ensuing courses of the minority patients who received NPWT for the entire duration of their wound care course. Conclusions This case series demonstrates desirable wound healing outcomes with the use of NPWT in the minority population. The authors draw attention to the outpatient benefit of this device that may be lost in those with limited insurance in minority populations and seek to encourage further studies in this population in resource-limited settings to determine its true clinical effectiveness.

Histological and clinical evaluation of wound healing in pressure ulcers: a novel animal model

OBJECTIVE

Pressure ulcers (PUs) are a major healthcare problem, commonly associated with older people, patients who are bedbound and patients with diabetes. The impact of PUs can decrease patients' quality of life, and lead to high morbidity and mortality rates. In this study, we aimed to describe a novel PU model that simulates pressure ulcers in humans to provide a research tool for new drug testing.

METHOD

Diabetes was induced using streptozocin in 75 adult Sprague Dawley rats. To create the PU, skin was sandwiched between two magnets, one of them implanted below the panniculus carnosus muscle and the other above the skin. The model was tested on nondiabetic rats and diabetic rats, each with pressure ulcers, compared to nondiabetic rats with excisional wounds.

RESULTS

Results showed that the PU model in diabetic (p-value<0.000001) and non-diabetic rats (p-value<0.05) exhibited significantly delayed healing (no healing over 21 days) compared with the excisional wound that was completely healed by day 21.

CONCLUSION

Diabetic rats showed significant changes in intact skin compared with non-diabetic rats, as well as a significant delay in the healing process compared with the non-diabetic group. By effectively impairing the skin contraction otherwise seen in the rats, and thereby delaying healing and making it similar to that seen in hard-to-heal PUs in humans, this model provides an effective tool for wound healing research.

Histological and clinical evaluation of wound healing in pressure ulcers: a novel animal model

OBJECTIVE

Pressure ulcers (PUs) are a major healthcare problem, commonly associated with older people, patients who are bedbound and patients with diabetes. The impact of PUs can decrease patients' quality of life, and lead to high morbidity and mortality rates. In this study, we aimed to describe a novel PU model that simulates pressure ulcers in humans to provide a research tool for new drug testing.

METHOD

Diabetes was induced using streptozocin in 75 adult Sprague Dawley rats. To create the PU, skin was sandwiched between two magnets, one of them implanted below the panniculus carnosus muscle and the other above the skin. The model was tested on nondiabetic rats and diabetic rats, each with pressure ulcers, compared to nondiabetic rats with excisional wounds.

RESULTS

Results showed that the PU model in diabetic (p-value<0.000001) and non-diabetic rats (p-value<0.05) exhibited significantly delayed healing (no healing over 21 days) compared with the excisional wound that was completely healed by day 21.

CONCLUSION

Diabetic rats showed significant changes in intact skin compared with non-diabetic rats, as well as a significant delay in the healing process compared with the non-diabetic group. By effectively impairing the skin contraction otherwise seen in the rats, and thereby delaying healing and making it similar to that seen in hard-to-heal PUs in humans, this model provides an effective tool for wound healing research.

Ca-Alginate-PEGMA Hydrogels for In Situ Delivery of TGF-β Neutralizing Antibodies in a Mouse Model of Wound Healing

Hydrogels provide effective alternatives for drug delivery when therapeutics cannot be applied directly to a wound, or if adverse effects are associated with systemic administration. However, drug delivery vehicles need to be biocompatible and biodegradable and exhibit sufficient mechanical strength to withstand handling and different physiological conditions, such as those encountered during topical administration of a therapeutic. Wound healing can be divided into three phases stimulated by transforming growth factor-beta (TGF-β) and, subsequently, targeted therapeutics have been developed to inhibit this cytokine for the treatment of chronic wounds and to prevent scarring. In this study, the capacity of calcium alginate hydrogels plasticized with poly(ethylene glycol) methyl ether methacrylate (PEGMA) to deliver anti-TGF-β antibodies (1D11.16.8) to a wound was investigated in situ. Three levels of antibodies, 10, 50, and 100 μg, were loaded into calcium-alginate-PEGMA hydrogels and evaluated in an excisional wound model in mice. Hydrogels containing 50 and 100 μg 1D11.16.8 produced less inflammation, accompanied by a marked reduction in collagen deposition and cell infiltration. These findings demonstrate the capacity of calcium-alginate-PEGMA hydrogels to deliver larger proteins, such as antibodies, to the site of a wound.

Efficacy of allogeneic cord blood platelet gel on wounds of dystrophic epidermolysis bullosa patients after pseudosyndactyly surgery

Epidermolysis bullosa (EB) is a rare genetic disorder characterized by the formation of blisters and wounds in skin and mucous membranes; it is classified into four types and has various methods of treatment. Management of previous wounds and prevention of formation of new lesions are the most important strategies in the course of therapy to improve patient's quality of life; lack of wound management can lead to further complications such as infection. The current study investigated the therapeutic effects of allogeneic platelet gel (prepared from umbilical cord blood) in a group of children diagnosed with dystrophic epidermolysis bullosa (DEB) eligible for surgical correction of pseudosyndactyly in the hand. The post-surgical clinical outcome in this group was compared with the clinical outcomes of DEB patients receiving the standard treatment (paraffin gauze wound dressing and topical antibiotics) after corrective surgery. The current study results showed an increase in the rate of recovery and promotion of tissue granulation, complete wound healing, and a decrease in pain level and treatment period. The application of cord blood platelet gel topical dressing was not a conventional method of treatment in patients with DEB wounds and blisters. However, the current study results demonstrated that this gel dressing could effectively accelerate epithelialization and healing of the wounds and decrease patients' pain and post-surgical recovery period, which altogether leads to improvements in patients' overall quality of life.

Negative pressure wound therapy in patients with wounds healing by secondary intention: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Negative pressure wound therapy (NPWT) is a widely used method of wound treatment. We performed a systematic review of randomised controlled trials (RCTs) comparing the patient-relevant benefits and harms of NPWT with standard wound therapy (SWT) in patients with wounds healing by secondary intention.

METHODS

We searched for RCTs in MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and study registries (last search: July 2018) and screened reference lists of relevant systematic reviews and health technology assessments. Manufacturers and investigators were asked to provide unpublished data. Eligible studies investigated at least one patient-relevant outcome (e.g. wound closure). We assessed publication bias and, if feasible, performed meta-analyses, grading the results into different categories (hint, indication or proof of a greater benefit or harm).

RESULTS

We identified 48 eligible studies of generally low quality with evaluable data for 4315 patients and 30 eligible studies with missing data for at least 1386 patients. Due to potential publication bias (proportion of inaccessible data, 24%), we downgraded our conclusions. A meta-analysis of all wound healing data showed a significant effect in favour of NPWT (OR 1.56, 95% CI 1.15 to 2.13, p = 0.008). As further analyses of different definitions of wound closure did not contradict that analysis, we inferred an indication of a greater benefit of NPWT. A meta-analysis of hospital stay (in days) showed a significant difference in favour of NPWT (MD - 4.78, 95% CI - 7.79 to - 1.76, p = 0.005). As further analyses of different definitions of hospital stay/readmission did not contradict that analysis, we inferred an indication of a greater benefit of NPWT. There was neither proof (nor indication nor hint) of greater benefit or harm of NPWT for other patient-relevant outcomes such as mortality and adverse events.

CONCLUSIONS

In summary, low-quality data indicate a greater benefit of NPWT versus SWT for wound closure in patients with wounds healing by secondary intention. The length of hospital stay is also shortened. The data show no advantages or disadvantages of NPWT for other patient-relevant outcomes. Publication bias is an important problem in studies on NPWT, underlining that all clinical studies need to be fully reported.

The use of negative pressure wound therapy in the primary setting for high-risk head and neck surgery

BACKGROUND

In head and neck surgery, dead space is typically managed by transferring a secondary pedicled flap or harvesting a larger composite flap with a muscular component. We demonstrate the novel use of prophylactic negative pressure wound therapy (NPWT) to obliterate dead space and reduce possible communication between the upper aerodigestive tract and the contents of the neck.

METHODS

We present a single-institutional case series of five patients with high-risk head and neck cancer treated with NPWT after ablative and reconstructive surgery to eliminate dead space following surgical resection.

RESULTS

All patients achieved successful wound closure following NPWT, which was applied in the secondary setting to combat infection in one patient and the primary setting to prophylactically eliminate dead space in four patients.

CONCLUSION

NPWT can be used to treat unfilled dead space in the primary setting of head and neck ablative and reconstructive surgery and help to avoid wound healing problems as well as the need for secondary flap transfers.

Negative pressure wound therapy versus standard treatment in patients with acute conflict-related extremity wounds: a pragmatic, multisite, randomised controlled trial

BACKGROUND

In armed conflict, injuries among civilians are usually complex and commonly affect the extremities. Negative pressure wound therapy (NPWT) is an alternative to standard treatment of acute conflict-related extremity wounds. We aimed to compare the safety and effectiveness of NPWT with that of standard treatment.

METHODS

In this pragmatic, randomised, controlled superiority trial done at two civilian hospitals in Jordan and Iraq, we recruited patients aged 18 years or older, presenting with a conflict-related extremity wound within 72 h after injury. Participants were assigned (1:1) to receive either NPWT or standard treatment. We used a predefined, computer-generated randomisation list with three block sizes. Participants and their treating physicians were not masked to treatment allocation. The primary endpoint was wound closure by day 5. The coprimary endpoint was net clinical benefit, defined as a composite of wound closure by day 5 and freedom from any bleeding, wound infection, sepsis, or amputation of the index limb. Analysis was by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT02444598, and is closed to accrual.

FINDINGS

Between June 9, 2015, and Oct 24, 2018, 174 patients were randomly assigned to either the NPWT group (n=88) or the standard treatment group (n=86). Five patients in the NPWT group and four in the standard treatment group were excluded from the intention-to-treat analysis. By day 5, 41 (49%) of 83 participants in the NPWT group and 49 (60%) of 82 participants in the standard treatment group had closed wounds, with an absolute difference of 10 percentage points (95% CI -5 to 25, p=0·212; risk ratio [RR] 0·83, 95% CI 0·62 to 1·09). Net clinical benefit was seen in 33 (41%) of 81 participants in the NPWT group and 34 (44%) of 78 participants in the standard treatment group, with an absolute difference of 3 percentage points (95% CI -12 to 18, p=0·750; RR 0·93, 95% CI 0·65 to 1·35). There was one in-hospital death in the standard treatment group and none in the NPWT group. The proportion of participants with sepsis, bleeding leading to blood transfusion, and limb amputation did not differ between groups.

INTERPRETATION

NPWT did not yield superior clinical outcomes compared with standard treatment for acute conflict-related extremity wounds. The results of this study not only question the use of NPWT, but also question the tendency for new and costly treatments to be introduced into resource-limited conflict settings without supporting evidence for their effectiveness. This study shows that high-quality, randomised trials in challenging settings are possible, and our findings support the call for further research that will generate context-specific evidence.

FUNDING

The Stockholm County Council, the Swedish National Board of Health and Welfare, and Médecins Sans Frontières.

Wound-Healing Following Negative-Pressure Wound Therapy with Use of a Locally Developed AquaVac System as Compared with the Vacuum-Assisted Closure (VAC) System

BACKGROUND

Negative-pressure wound therapy (NPWT) gained widespread clinical use after its introduction in the 1990s because of its many beneficial effects on the wound environment. However, high treatment costs have limited its use in third-world countries. The present study compares a low-cost, locally developed NPWT system with a commercially available system in terms of efficacy, reliability, ease of application, and safety.

METHODS

This prospective, randomized controlled trial involved 36 patients who were managed with NPWT with either a low-cost, locally developed system (AquaVac) or a commercially available Vacuum-Assisted Closure Advanced Therapy System (VAC ATS; KCI). The low-cost NPWT system described consists of a converted aquarium pump as a reusable vacuum source and a dressing system that can be found in the hospital supply room: food plastic wrap as an occlusive drape, surgical gauze as wound filler, nasogastric tubes as tubing, and used intravenous (IV) bottles as effluent canisters. The purpose of the study was to compare the 2 systems in terms of (1) time to apply the dressing, (2) exudate levels, (3) amount of granulation tissue, (4) wound size reduction, (5) average cost of treatment, (6) visual analog scale (VAS) pain scores, and (7) complications.

RESULTS

The experimental low-cost system had a small but statistically insignificant advantage over the commercially available system in terms of application time, pain during dressing changes, and wound contraction percentage. The 2 systems were comparable in terms of the amount of exudate, granulation tissue coverage, and VAS scores during the course of treatment. No wound or periwound complications were observed. The systems were significantly different in terms of cost, with the AquaVac system being 7 times less expensive than the VAC ATS system ($63.75 compared with $491.38 USD).

CONCLUSIONS

The low-cost AquaVac system was shown to be comparable with the commercial VAC ATS system, suggesting that it is an effective and safe alternative method for NPWT in resource-challenged settings.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Surgical Site Infections Complicating the Use of Negative Pressure Wound Therapy in Renal Transplant Recipients

Surgical site infections (SSI) of the abdominal wall in renal transplant recipients can on occasion require management with negative pressure wound therapy (NPWT). This is often successful, with a low risk of further complications. However, we describe three cases in which persistent or recurrent surgical site sepsis occurred, whilst NPWT was being deployed in adults with either wound dehiscence or initial SSI. This type of complication in the setting of NPWT has not been previously described in renal transplant recipients. Our case series demonstrates that in immunosuppressed transplant recipients, there may be ineffective microbial or bacterial bioburden clearance associated with the NPWT, which can lead to further infections. Hence recognition for infections in renal transplant patients undergoing treatment with NPWT is vital; furthermore, aggressive management of sepsis control with early debridement, antimicrobial use, and reassessment of the use of wound dressing is necessary to reduce the morbidity associated with surgical site infections and NPWT.

Pilot Study to Assess Safety and Usability of the Kyron NPWT System

There is an evident need for Negative Pressure Wound Therapy (NPWT) systems specifically designed for use in resource-constrained settings to aid in the treatment of open wounds.

Negative pressure wound therapy for treating foot wounds in people with diabetes mellitus

BACKGROUND

Foot wounds in people with diabetes mellitus (DM) are a common and serious global health issue. People with DM are prone to developing foot ulcers and, if these do not heal, they may also undergo foot amputation surgery resulting in postoperative wounds. Negative pressure wound therapy (NPWT) is a technology that is currently used widely in wound care. NPWT involves the application of a wound dressing attached to a vacuum suction machine. A carefully controlled negative pressure (or vacuum) sucks wound and tissue fluid away from the treated area into a canister. A clear and current overview of current evidence is required to facilitate decision-making regarding its use.

OBJECTIVES

To assess the effects of negative pressure wound therapy compared with standard care or other therapies in the treatment of foot wounds in people with DM in any care setting.

SEARCH METHODS

In January 2018, for this first update of this review, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies, reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. We identified six additional studies for inclusion in the review.

SELECTION CRITERIA

Published or unpublished randomised controlled trials (RCTs) that evaluated the effects of any brand of NPWT in the treatment of foot wounds in people with DM, irrespective of date or language of publication. Particular effort was made to identify unpublished studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment and data extraction. Initial disagreements were resolved by discussion, or by including a third review author when necessary. We presented and analysed data separately for foot ulcers and postoperative wounds.

MAIN RESULTS

Eleven RCTs (972 participants) met the inclusion criteria. Study sample sizes ranged from 15 to 341 participants. One study had three arms, which were all included in the review. The remaining 10 studies had two arms. Two studies focused on postamputation wounds and all other studies included foot ulcers in people with DM. Ten studies compared NPWT with dressings; and one study compared NPWT delivered at 75 mmHg with NPWT delivered at 125 mmHg. Our primary outcome measures were the number of wounds healed and time to wound healing.NPWT compared with dressings for postoperative woundsTwo studies (292 participants) compared NPWT with moist wound dressings in postoperative wounds (postamputation wounds). Only one study specified a follow-up time, which was 16 weeks. This study (162 participants) reported an increased number of healed wounds in the NPWT group compared with the dressings group (risk ratio (RR) 1.44, 95% confidence interval (CI) 1.03 to 2.01; low-certainty evidence, downgraded for risk of bias and imprecision). This study also reported that median time to healing was 21 days shorter with NPWT compared with moist dressings (hazard ratio (HR) calculated by review authors 1.91, 95% CI 1.21 to 2.99; low-certainty evidence, downgraded for risk of bias and imprecision). Data from the two studies suggest that it is uncertain whether there is a difference between groups in amputation risk (RR 0.38, 95% CI 0.14 to 1.02; 292 participants; very low-certainty evidence, downgraded once for risk of bias and twice for imprecision).NPWT compared with dressings for foot ulcersThere were eight studies (640 participants) in this analysis and follow-up times varied between studies. Six studies (513 participants) reported the proportion of wounds healed and data could be pooled for five studies. Pooled data (486 participants) suggest that NPWT may increase the number of healed wounds compared with dressings (RR 1.40, 95% CI 1.14 to 1.72; I² = 0%; low-certainty evidence, downgraded once for risk of bias and once for imprecision). Three studies assessed time to healing, but only one study reported usable data. This study reported that NPWT reduced the time to healing compared with dressings (hazard ratio (HR) calculated by review authors 1.82, 95% CI 1.27 to 2.60; 341 participants; low-certainty evidence, downgraded once for risk of bias and once for imprecision).Data from three studies (441 participants) suggest that people allocated to NPWT may be at reduced risk of amputation compared with people allocated to dressings (RR 0.33, 95% CI 0.15 to 0.70; I² = 0%; low-certainty evidence; downgraded once for risk of bias and once for imprecision).Low-pressure compared with high-pressure NPWT for foot ulcersOne study (40 participants) compared NPWT 75 mmHg and NPWT 125 mmHg. Follow-up time was four weeks. There were no data on primary outcomes. There was no clear difference in the number of wounds closed or covered with surgery between groups (RR 0.83, 95% CI 0.47 to 1.47; very low-certainty evidence, downgraded once for risk of bias and twice for serious imprecision) and adverse events (RR 1.50, 95% CI 0.28 to 8.04; very low-certainty evidence, downgraded once for risk of bias and twice for serious imprecision).

AUTHORS' CONCLUSIONS

There is low-certainty evidence to suggest that NPWT, when compared with wound dressings, may increase the proportion of wounds healed and reduce the time to healing for postoperative foot wounds and ulcers of the foot in people with DM. For the comparisons of different pressures of NPWT for treating foot ulcers in people with DM, it is uncertain whether there is a difference in the number of wounds closed or covered with surgery, and adverse events. None of the included studies provided evidence on time to closure or coverage surgery, health-related quality of life or cost-effectiveness. The limitations in current RCT evidence suggest that further trials are required to reduce uncertainty around decision-making regarding the use of NPWT to treat foot wounds in people with DM.

Use of a novel epidermal harvesting system in resource-poor countries

The 2010 earthquake in Port-au-Prince, Haiti, highlighted the need for wound care in resource-poor countries. Subsequently, the University of Miami in Florida established one of the first interprofessional wound care centers located at Bernard Mevs Hospital in the central portion of Port-au-Prince, caring for patients with acute and chronic wounds. In 2012, the authors used a novel epidermal harvesting system (CelluTome Epidermal Harvesting System; Kinetic Concepts Inc, San Antonio, Texas) to harvest epithelium to be grafted on 7 patients at the Mevs Hospital with longstanding wounds. Epidermal microblisters were obtained from each patient's thigh using the CelluTome Epidermal Harvesting System. After 35 minutes, microblisters were raised using the device harvester, and an adhesive dressing was inserted into the harvester for transfer to the wound site. In patients with lower-extremity wounds, a 2-layer compression dressing was placed over epidermal grafts. Six of the 7 wounds improved or achieved complete closure in 4 weeks. One of the patients with a 2-year-old thigh wound failed to demonstrate improvement; this may have been secondary to an inability to adequately secure the graft. All donor sites healed without any visible scarring. The authors were able to conclude that epidermal grafting may represent a viable reconstructive option for patients in resource-poor countries.

Role of negative pressure wound therapy in total hip and knee arthroplasty

Negative-pressure wound therapy (NPWT) has been a successful modality of wound management which is in widespread use in several surgical fields. The main mechanisms of action thought to play a role in enhancing wound healing and preventing surgical site infection are macrodeformation and microdeformation of the wound bed, fluid removal, and stabilization of the wound environment. Due to the devastating consequences of infection in the setting of joint arthroplasty, there has been some interest in the use of NPWT following total hip arthroplasty and total knee arthroplasty. However, there is still a scarcity of data reporting on the use of NPWT within this field and most studies are limited by small sample sizes, high variability of clinical settings and end-points. There is little evidence to support the use of NPWT as an adjunctive treatment for surgical wound drainage, and for this reason surgical intervention should not be delayed when indicated. The prophylactic use of NPWT after arthroplasty in patients that are at high risk for postoperative wound drainage appears to have the strongest clinical evidence. Several clinical trials including single-use NPWT devices for this purpose are currently in progress and this may soon be incorporated in clinical guidelines as a mean to prevent periprosthetic joint infections.

Biocompatible and biodegradable poly(Tannic Acid) hydrogel with antimicrobial and antioxidant properties

A novel resourceful bulk poly(Tannic Acid) (p(TA)) hydrogel was prepared by crosslinking TA molecules with an epoxy crosslinker, trimethylolpropane triglycidyl ether (TMPGDE), in an autoclave at 90°C for 2h. The obtained p(TA) hydrogels were in disk form and have highly porous morphology. The swelling characteristics of p(TA) hydrogels were investigated in wound healing pH conditions of pH 5.4, 7.4, and 9 at 37.5°C, and the hydrogels showed good swelling and moisture content behavior. Especially, p(TA) hydrogels were found to be sensitive to pH 9 with 1669% maximum swelling. P(TA) hydrogels were completely degraded at pH 9 hydrolytically in 9 days. Total phenol contents and the effects of scavenging ABTS(+) radicals of degraded p(TA) hydrogels at pH 5.4, 7.4, and 9 were evaluated and calculated in terms of gallic acid equivalent and trolox equivalent antioxidant capacity, respectively, and found to be very effective. Moreover, degraded p(TA) hydrogels display strong antimicrobial behavior against gram positive Staphylococcus aureus, Bacillus subtilis, gram negative Pseudomonas aeruginosa bacteria strains and Candida albicans fungus strain. The WST-1 results indicated that bulk p(TA) hydrogels have no cyctotoxicity to the L929 fibroblast cell line in vitro.

Negative pressure wound therapy for treating leg ulcers

BACKGROUND

Leg ulcers are open skin wounds that occur between the ankle and the knee that can last weeks, months or even years and are a consequence of arterial or venous valvular insufficiency. Negative pressure wound therapy (NPWT) is a technology that is currently used widely in wound care and is promoted for use on wounds. NPWT involves the application of a wound dressing to the wound, to which a machine is attached. The machine applies a carefully controlled negative pressure (or vacuum), which sucks any wound and tissue fluid away from the treated area into a canister.

OBJECTIVES

To assess the effects of negative pressure wound therapy (NPWT) for treating leg ulcers in any care setting.

SEARCH METHODS

For this review, in May 2015 we searched the following databases: the Cochrane Wounds Group Specialised Register (searched 21 May 2015); the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library 2015, Issue 4); Ovid MEDLINE (1946 to 20 May 2015); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 20 May 2015); Ovid EMBASE (1974 to 20 May 2015); EBSCO CINAHL (1982 to 21 May 2015). There were no restrictions based on language or date of publication.

SELECTION CRITERIA

Published or unpublished randomized controlled trials (RCTs) comparing the effects of NPWT with alternative treatments or different types of NPWT in the treatment of leg ulcers.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment and data extraction.

MAIN RESULTS

We included one study, with 60 randomized participants, in the review. The study population had a range of ulcer types that were venous arteriolosclerotic and venous/arterial in origin. Study participants had recalcitrant ulcers that had not healed after treatment over a six-month period. Participants allocated to NPWT received continuous negative pressure until they achieved 100% granulation (wound preparation stage). A punch skin-graft transplantation was conducted and the wound then exposed to further NPWT for four days followed by standard care. Participants allocated to the control arm received standard care with dressings and compression until 100% granulation was achieved. These participants also received a punch skin-graft transplant and then further treatment with standard care. All participants were treated as in-patients until healing occurred.There was low quality evidence of a difference in time to healing that favoured the NPWT group: the study reported an adjusted hazard ratio of 3.2, with 95% confidence intervals (CI) 1.7 to 6.2. The follow-up period of the study was a minimum of 12 months. There was no evidence of a difference in the total number of ulcers healed (29/30 in each group) over the follow-up period; this finding was also low quality evidence.There was low quality evidence of a difference in time to wound preparation for surgery that favoured NPWT (hazard ratio 2.4, 95% CI 1.2 to 4.7).Limited data on adverse events were collected: these provided low quality evidence of no difference in pain scores and Euroqol (EQ-5D) scores at eight weeks after surgery.

AUTHORS' CONCLUSIONS

There is limited rigorous RCT evidence available concerning the clinical effectiveness of NPWT in the treatment of leg ulcers. There is some evidence that the treatment may reduce time to healing as part of a treatment that includes a punch skin graft transplant, however, the applicability of this finding may be limited by the very specific context in which NPWT was evaluated. There is no RCT evidence on the effectiveness of NPWT as a primary treatment for leg ulcers.

Negative pressure wound therapy for treating surgical wounds healing by secondary intention

BACKGROUND

Following surgery, incisions are usually closed by fixing the edges together with sutures (stitches), staples, adhesive glue or clips. This process helps the cut edges heal together and is called 'healing by primary intention'. However, not all incised wounds are closed in this way: where there is high risk of infection, or when there has been significant tissue loss, wounds may be left open to heal from the 'bottom up'. This delayed healing is known as 'healing by secondary intention'. Negative pressure wound therapy (NPWT) is one treatment option for surgical wounds that are healing by secondary intention.

OBJECTIVES

To assess the effects of negative pressure wound therapy (NPWT) on the healing of surgical wounds healing by secondary intention (SWHSI) in any care setting.

SEARCH METHODS

For this review, in May 2015 we searched the following databases: the Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials; Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations; Ovid EMBASE; and EBSCO CINAHL. There were no restrictions based on language or date of publication.

SELECTION CRITERIA

Published or unpublished randomised controlled trials (RCTs) comparing the effects of NPWT with alternative treatments or different types of NPWT in the treatment of SWHSI. We excluded open abdominal wounds from this review as they are the subject of a separate Cochrane review that is in draft.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment and data extraction.

MAIN RESULTS

We located two studies (69 participants) for inclusion in this review. One study compared NPWT with an alginate dressing in the treatment of open, infected groin wounds. and one study compared NPWT with a silicone dressing in the treatment of excised pilonidal sinus. The trials reported limited outcome data on healing, adverse events and resource use.

AUTHORS' CONCLUSIONS

There is currently no rigorous RCT evidence available regarding the clinical effectiveness of NPWT in the treatment of surgical wounds healing by secondary intention as defined in this review. The potential benefits and harms of using this treatment for this wound type remain largely uncertain.

Wound management in disaster settings

BACKGROUND

Few guidelines exist for the initial management of wounds in disaster settings. As wounds sustained are often contaminated, there is a high risk of further complications from infection, both local and systemic. Healthcare workers with little to no surgical training often provide early wound care, and where resources and facilities are also often limited, and clear appropriate guidance is needed for early wound management.

METHODS

We undertook a systematic review focusing on the nature of wounds in disaster situations, and the outcomes of wound management in recent disasters. We then presented the findings to an international consensus panel with a view to formulating a guideline for the initial management of wounds by first responders and subsequent healthcare personnel as they deploy.

RESULTS

We included 62 studies in the review that described wound care challenges in a diverse range of disasters, and reported high rates of wound infection with multiple causative organisms. The panel defined a guideline in which the emphasis is on not closing wounds primarily but rather directing efforts toward cleaning, debridement, and dressing wounds in preparation for delayed primary closure, or further exploration and management by skilled surgeons.

CONCLUSION

Good wound care in disaster settings, as outlined in this article, can be achieved with relatively simple measures, and have important mortality and morbidity benefits.

A Multicenter Randomized Controlled Trial Comparing Treatment of Venous Leg Ulcers Using Mechanically Versus Electrically Powered Negative Pressure Wound Therapy

Objective: This study compares two different negative pressure wound therapy (NPWT) modalities in the treatment of venous leg ulcers (VLUs), the ultraportable mechanically powered (MP) Smart Negative Pressure (SNaP^®) Wound Care System to the electrically powered (EP) Vacuum-Assisted Closure (V.A.C.^®) System. Approach: Patients with VLUs from 13 centers participated in this prospective randomized controlled trial. Each subject was randomly assigned to treatment with either MP NPWT or EP NPWT and evaluated for 16 weeks or complete wound closure. Results: Forty patients (n=19 MP NPWT and n=21 EP NPWT) completed the study. Primary endpoint analysis of wound size reduction found wounds in the MP NPWT group had significantly greater wound size reduction than those in the EP NPWT group at 4, 8, 12, and 16 weeks (p-value=0.0039, 0.0086, 0.0002, and 0.0005, respectively). Kaplan-Meier analyses showed greater acceleration in complete wound closure in the MP NPWT group. At 30 days, 50% wound closure was achieved in 52.6% (10/19) of patients treated with MP NPWT and 23.8% (5/21) of patients treated with EP NPWT. At 90 days, complete wound closure was achieved in 57.9% (11/19) of patients treated with MP NPWT and 38.15% (8/21) of patients treated with EP NPWT. Innovation: These data support the use of MP-NPWT for the treatment of VLUs. Conclusions: In this group of venous ulcers, wounds treated with MP NPWT demonstrated greater improvement and a higher likelihood of complete wound closure than those treated with EP NPWT.

Negative pressure wound therapy for skin grafts and surgical wounds healing by primary intention

BACKGROUND

Indications for the use of negative pressure wound therapy (NPWT) are broadening with a range of systems now available on the market, including those designed for use on clean, closed incisions and skin grafts. Reviews have concluded that the evidence for the effectiveness of NPWT remains uncertain, however, it is a rapidly evolving therapy. Consequently, an updated systematic review of the evidence for the effects of NPWT on postoperative wounds expected to heal by primary intention is required.

OBJECTIVES

To assess the effects of NPWT on surgical wounds (primary closure, skin grafting or flap closure) that are expected to heal by primary intention.

SEARCH METHODS

We searched the following electronic databases to identify reports of relevant randomised clinical trials: the Cochrane Wounds Group Specialised Register (searched 28 January 2014); the Cochrane Central Register of Controlled Trials (CENTRAL; 2013, issue 12); Database of Abstracts of Reviews of Effects (2013, issue 12); Ovid MEDLINE (2011 to January 2014); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 24 January 2014); Ovid EMBASE (2011 to January 2014 Week 44); and EBSCO CINAHL (2011 to January 2014). We conducted a separate search to identify economic evaluations.

SELECTION CRITERIA

We included trials if they allocated patients to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with a different type of NPWT.

DATA COLLECTION AND ANALYSIS

We assessed trials for their appropriateness for inclusion and for their quality. This was done by three review authors working independently, using pre-determined inclusion and quality criteria.

MAIN RESULTS

In this first update, we included an additional four trials, taking the total number of trials included to nine (785 participants). Three trials involved skin grafts, four included orthopaedic patients and two included general surgery and trauma surgery patients; all the included trials had unclear or high risk of bias for one or more of the quality indicators we assessed. Seven trials compared NPWT with a standard dressing (two of these were 'home-made' NPWT devices), one trial compared one 'home-made' NPWT with a commercially available device. In trials where the individual was the unit of randomisation, there were no differences in the incidence of surgical site infections (SSI); wound dehiscence, re-operation (in incisional wounds); seroma/haematoma; or failed skin grafts. Lower re-operation rates were observed among skin graft patients in the 'home-made' NPWT group (7/65; 10.8%) compared to the standard dressing group (17/66; 25.8%) (risk ratio (RR) 0.42; 95% CI 0.19 to 0.92). The mean cost to supply equipment for VAC® therapy was USD 96.51/day compared to USD 4.22/day for one of the 'home-made' devices (P value 0.01); labour costs for dressing changes were similar for both treatments. Pain intensity score was also reported to be lower in the 'home-made' group when compared with the VAC® group (P value 0.02). One of the trials in orthopaedic patients was stopped early because of a high incidence of fracture blisters in the NPWT group (15/24; 62.5%) compared with the standard dressing group (3/36; 8.3%) (RR 7.50; 95% CI 2.43 to 23.14).

AUTHORS' CONCLUSIONS

Evidence for the effects of negative pressure wound therapy (NPWT) for reducing SSI and wound dehiscence remains unclear, as does the effect of NPWT on time to complete healing. Rates of graft loss may be lower when NPWT is used, but hospital-designed and built products are as effective in this area as commercial applications. There are clear cost benefits when non-commercial systems are used to create the negative pressure required for wound therapy, with no evidence of a negative effect on clinical outcome. In one study, pain levels were also rated lower when a 'home-made' system was compared with a commercial counterpart. The high incidence of blisters occurring when NPWT is used following orthopaedic surgery suggests that the therapy should be limited until safety in this population is established. Given the cost and widespread use of NPWT, there is an urgent need for suitably powered, high-quality trials to evaluate the effects of the newer NPWT products that are designed for use on clean, closed surgical incisions. Such trials should focus initially on wounds that may be difficult to heal, such as sternal wounds or incisions on obese patients.

Negative pressure wound therapy decreases mortality in a murine model of burn-wound sepsis involving Pseudomonas aeruginosa infection

Background

The colonization of burn wounds by Pseudomonas aeruginosa can lead to septic shock, organ injuries, and high mortality rates. We hypothesized that negative pressure wound therapy (NPWT) would decrease invasion and proliferation of P. aeruginosa within the burn wound and reduce mortality.

Methods

Thermal injuries were induced in anesthetized mice, and P. aeruginosa was applied to the wound surface for 24 h. After removing the burn eschar and debridement, the animals were subjected to either NPWT or wet-to-dry (WTD) treatment protocols. The bacterial loads on the wound surface were assessed during 7 d of treatment, as were the concentrations of inflammatory cytokines in the peripheral blood samples. Survival was monitored daily for 14 d after burn induction. Finally, samples of wounded skin, lung, liver, and kidney were collected and subjected to histopathological examination.

Results

Applying P. aeruginosa to the burn wound surface led to sepsis. During early stages of treatment, NPWT reduced the mortality of the septic animals and levels of P. aeruginosa within the burn wound compared with WTD-treated animals. Circulating levels of cytokines and cytoarchitectural abnormalities were also significantly reduced via NPWT.

Conclusions

Our data indicate that NPWT inhibits the invasion and proliferation of P. aeruginosa in burn-wounded tissue and decreases early mortality in a murine model of burn-wound sepsis. These therapeutic benefits likely result from the ability of NPWT to decrease bacterial proliferation on the wound surface, reduce cytokine serum concentrations, and prevent damage to internal organs.

Negative pressure wound therapy for treating foot wounds in people with diabetes mellitus

BACKGROUND

Foot wounds in people with diabetes mellitus (DM) are a common and serious global health issue. Negative pressure wound therapy can be used to treat these wounds and a clear and current overview of current evidence is required to facilitate decision-making regarding its use.

OBJECTIVES

To assess the effects of negative pressure wound therapy compared with standard care or other adjuvant therapies in the healing of foot wounds in people with DM.

SEARCH METHODS

In July 2013, we searched the following databases to identify reports of relevant randomised controlled trials (RCTs): Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL); The Database of Abstracts of Reviews of Effects (DARE); The NHS Economic Evaluation Database; Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL.

SELECTION CRITERIA

Published or unpublished RCTs that evaluate the effects of any brand of negative pressure wound therapy in the treatment of foot wounds in people with diabetes, irrespective of publication date or language of publication. Particular effort was made to identify unpublished studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment and data extraction.

MAIN RESULTS

We included five studies in this review randomising 605 participants. Two studies (total of 502 participants) compared negative pressure wound therapy with standard moist wound dressings. The first of these was conducted in people with DM and post-amputation wounds and reported that significantly more people healed in the negative pressure wound therapy group compared with the moist dressing group: (risk ratio 1.44; 95% CI 1.03 to 2.01). The second study, conducted in people with debrided foot ulcers, also reported a statistically significant increase in the proportion of ulcers healed in the negative pressure wound therapy group compared with the moist dressing group: (risk ratio 1.49; 95% CI 1.11 to 2.01). However, these studies were noted to be at risk of performance bias, so caution is required in their interpretation. Findings from the remaining three studies provided limited data, as they were small, with limited reporting, as well as being at unclear risk of bias.

AUTHORS' CONCLUSIONS

There is some evidence to suggest that negative pressure wound therapy is more effective in healing post-operative foot wounds and ulcers of the foot in people with DM compared with moist wound dressings. However, these findings are uncertain due to the possible risk of bias in the original studies. The limitations in current RCT evidence suggests that further trials are required to reduce uncertainty around decision making regarding the use of NPWT to treat foot wounds in people with DM.

Negative pressure wound therapy for skin grafts and surgical wounds healing by primary intention

BACKGROUND

Indications for the use of negative pressure wound therapy (NPWT) are broadening with a range of systems on the market, including those designed for use on clean, closed incisions and skin grafts. Reviews have concluded that the evidence for the effectiveness of NPWT remains uncertain. However, this is a rapidly evolving therapy. Consequently, a systematic review of the evidence for the effects of NPWT on postoperative wounds expected to heal by primary intention is required.

OBJECTIVES

To assess the effects of NPWT on surgical wounds (primary closure or skin grafting) that are expected to heal by primary intention.

SEARCH METHODS

We searched the following electronic databases to identify reports of relevant randomised clinical trials: the Cochrane Wounds Group Specialised Register (searched 11 November 2011); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 4); Database of Abstracts of Reviews of Effects (The Cochrane Library 2011, Issue 4); Ovid MEDLINE (2005 to October Week 4 2011); Ovid MEDLINE (In-Process & Other Non-Indexed Citations 8 November 2011); Ovid EMBASE (2009 to 2011 Week 44); and EBSCO CINAHL (1982 to 04 November 2011). We conducted a separate search to identify economic evaluations.

SELECTION CRITERIA

We included trials if they allocated patients at random and compared NPWT with any other type of wound dressing or compared one type of NPWT with a different type of NPWT.

DATA COLLECTION AND ANALYSIS

We assessed trials for their appropriateness for inclusion and for their quality. This was done by three review authors working independently, using pre-determined inclusion and quality criteria.

MAIN RESULTS

We included five eligible trials with a total of 280 participants. Two trials involved skin grafts and three acute wounds. Only one of the five trials reported the proportion of wounds completely healed and in this study all wounds healed. All five studies reported adverse events. In the four trials that compared standard dressings with negative pressure wound therapy (NPWT) the adverse event rate was similar between groups (negative pressure 33/86; standard dressing 37/103); risk ratio (RR) 0.97 (95% confidence intervals (CI) 0.33 to 2.89). There was significant heterogeneity for this result, due to the high incidence of fracture blisters in the NPWT group in one trial. One trial (87 participants) compared a commercial negative pressure device VAC® system with a negative pressure system developed in the hospital (GSUC). The adverse event rate was lower in the GSUC group (VAC® 3/42; GSUC 0/45); the RR was 0.13 (95% CI 0.01 to 2.51). Results indicate uncertainty about the true effect of either method on adverse events. The mean cost to supply equipment for VAC® therapy was USD 96.51/day compared to USD 4.22/day for the GSUC therapy (P = 0.01). Labour costs for dressing changes were similar. Pain intensity score was also reported to be lower in the GSUC group when compared with the VAC® group (p = 0.02)

AUTHORS' CONCLUSIONS

Evidence for the effectiveness of NPWT on complete healing of wounds expected to heal by primary intention remains unclear. Rates of graft loss may be lower when NPWT is used; but evidence to date suggests that hospital-based products are as effective in this area as commercial applications. There are clear cost benefits when non-commercial systems are used to create the negative pressure required for wound therapy, with no reduction in clinical outcome. Pain levels are also rated lower when hospital systems are compared with their commercial counterparts. The high incidence of blisters occurring when NPWT is used following orthopaedic surgery suggests that the therapy should be limited until safety in this population is established. Given the cost and widespread use of NPWT, there is an urgent need for suitably powered, high-quality trials to evaluate the effects of the newer NPWT products that are designed for use on clean, closed surgical incisions. Such trials should focus initially on wounds that may be difficult to heal, such as sternal wounds or surgeries for obese patients.

Negative pressure wound therapy in acute, contaminated wounds: documenting its safety and efficacy to support current global practice

Negative pressure wound therapy (NPWT) is in widespread use and its role in wound care is expanding worldwide. It is estimated that 300 million acute wounds are treated globally each year. Currently, sporadic data exist to support NPWT in acutely contaminated wounds. Despite lack of data, use of negative pressure wound therapy in such cases is increasing across the globe. We retrospectively reviewed 86 consecutive patients, totalling 97 contaminated wounds. All wounds were Class IV based on US Center for Disease Control criteria. Sepsis criteria were present in 78/86 (91%) of patients. All patients were managed with NPWT. Wound type, degree of tissue destruction, presence of infection, wound dimension, timing of initial NPWT, type and timing of wound closure and patient comorbidities were recorded. Outcome endpoints included durability of wound closure and death. Wound location was 41/97 (42%) in the torso; 56/97 (58%) at the extremities. Tissue necrosis was present in 84/97 (87%) of wounds. Infection was present in 86/97 (89%) of wounds. Average wound size was 619 cm(2) when square surface area measured; 786 cm(3) when volume measurements taken. Mean time to wound closure was 17 days, median 10 days and mode 6 days. Durability of wound closure 73/79 (92%). Deaths were noted in 6/86 (7%) of patients. No deaths appeared related to NPWT. Contemporary NPWT related acute wound care is expanding empirically, in quantity and scope across the globe. However, several areas of concern are known regarding this contemporary use of NPWT in acute wounds. Thus, it is important to assess the safety and efficacy of such expanded empiric NPWT practice. Based on our findings with NPWT in the largest known patient cohort of this type, NPWT appears safe and effective in managing acute, contaminated wounds including patients meeting sepsis criteria. These findings provide evidence-based support for current worldwide empiric NPWT-related acute wound care.

The Haiti earthquake: the provision of wound care for mass casualties utilizing negative-pressure wound therapy

Many months after the devastating earthquake in January 2010, wounds remain a major disease burden in Haiti. Since January 2010, through the efforts of corporations, nonprofit charitable organizations, and medical professionals, advanced wound care techniques, including negative-pressure wound therapy (NPWT), have been introduced into the wound care regimens of various hospitals in Haiti. In June 2010, the authors completed their second volunteer trip at a Haitian hospital specializing in orthopedic wounds. The medical team was composed of a plastic surgeon, orthopedic surgeon, anesthesiologist, medical assistant, scrub technician, and registered nurse (specializing in plastic surgery and orthopedics). The authors' team supplied NPWT devices, reticulated open-cell foam dressings, and canisters donated by Kinetic Concepts, Inc, San Antonio, Texas, for use at the hospital. This report describes the medical challenges in postearthquake Haiti (including limb salvage and infection), benefits of adjunctive use of NPWT/reticulated open-cell foam, and current wound care status in a Haitian orthopedic hospital. The future role of NPWT in Haiti and during mass catastrophe in a least-developed country is also discussed.

Negative-pressure wound therapy: systematic review of randomized controlled trials

BACKGROUND

In negative-pressure wound therapy (NPWT), a wound is covered with an airtight dressing, and negative pressure is applied. This is thought to promote healing. We evaluated NPWT with an updated, systematic review of the literature.

METHODS

We systematically searched the PubMed and Cochrane Library databases for randomized, controlled trials (RCTs) of NPWT for the treatment of acute or chronic wounds. The primary outcome was complete wound closure.

RESULTS

We found reports of 9 RCTs in addition to the 12 covered by earlier IQWiG reviews of this topic. Five of the 9 new trials involved NPWT systems that are not on the market. The frequency of complete wound closure is stated in only 5 of the 9 new reports; a statistically significant effect in favor of NPWT was found in only two trials.The results of 8 of the 9 new trials are hard to interpret, both because of apparent bias and because diverse types of wounds were treated.

CONCLUSION

Although there may be a positive effect of NPWT, we did not find clear evidence that wounds heal any better or worse with NPWT than with conventional treatment. Good RCTs are still needed to evaluate NPWT.