Negative pressure wound therapy for treating leg ulcers

Intermittent negative pressure influences popliteal artery shear rate during supine and sitting postures

Background: Intermittent negative pressure is an emerging treatment for lower limb vascular disease but the specific physiological effects, particularly upon large artery haemodynamics are unclear. This study examined the influence of intermittent negative pressure upon popliteal artery shear rate during both supine and sitting postures. Participants and methods: Eleven healthy participants (5 female; age: 28.3 ± 5.8 y; weight: 69.6 ± 9.8 kg, height: 1.75 ± 0.07 m) received intermittent negative pressure (-37 mmHg; 9.5-sec on, 7.5-sec off), upon the lower leg during both supine and sitting postures. Popliteal artery blood flow and shear rate were recorded (duplex ultrasound), accompanied by heart rate (3-lead ECG) and blood pressure (volume clamp method). Results: Compared to sitting, a supine posture led to greater mean shear rate during baseline (supine: 21[9]; sitting: 17[13] sec-1; all median [IQR]) and negative pressure phases (supine: 24[15]; sitting: 17[14] sec-1; both p<0.05). While supine, negative pressure raised mean shear rate above baseline levels (p<0.05) and reduced it upon return to atmospheric pressure (p < 0.05). In sitting, mean shear rate only differed from baseline at the points of peak and minimum shear (peak:18[17]; minimum: 10[9] sec-1; both p<0.05). Shear pattern (oscillatory shear index) showed changes from baseline during both postures (p<0.05), but was not different between postures. Conclusions: Intermittent negative pressure influenced lower limb popliteal artery shear rate during both the supine and sitting postures, the effect was greater while supine. Fluctuation in shear pattern seen during both positions may account for positive clinical effects observed following intermittent negative pressure treatment. These findings are framed against previous work investigating clinical populations. Future work should investigate any differences in lower limb haemodynamics and markers of endothelial function among patients with vascular disease.

SCI-QOL and WOUND-Q Have the Best Patient-reported Outcome Measure Design: A Systematic Literature Review of PROMs Used in Chronic Wounds

Chronic wounds are a significant burden on healthcare systems due to high costs of care (2%-4% total healthcare cost) and a considerable burden on patient's quality of life. Patient-reported outcome measures (PROMs) are questionnaires developed to enable patient self-assessments of their outcomes. A gap in knowledge exists because previous reviews on wound-specific PROMs did not evaluate the quality of the development. The main question is which PROM has the best quality development properties and should be used in clinical care and research.

Methods

PubMed, Embase, and CINAHL were searched from their inception through December 2021. Studies that included patients aged 18 years or older, with chronic wounds, and who reported using a condition-specific PROM for wounds were extracted. We excluded generic PROMs, comments, guidelines, and editorial letters. The COSMIN-guidelines were used to evaluate the quality of the PROMs.

Results

Of the 16,356 articles, a total of 251 articles describing 33 condition-specific PROMs for wounds were used. In total, 17 of 33 (52%) PROMs were developed for specific wound types, and nine of 33 (27%) PROMs were developed for any type of wound. Two of 33 (6%) PROMs were not rated because no development article was available. Only the SCI-QOL (Spinal Cord Injury-QOL) and the WOUND-Q rated "very good" in PROM design.

Conclusions

Thirty-three condition-specific PROMs were found. Only the SCI-QOL and the WOUND-Q rated very good in PROM design. The WOUND-Q is the only condition-specific PROM, which can be used in all types of chronic wounds in any anatomic location.

High Versus Low Frequency Transcutaneous Electric Nerve Stimulation On Chronic Venous Lower Limb Ulceration Randomized Controlled Trial

The major objective of the current paper is to trace and investigate which method is more effective whether the high or the low Transcutaneous electric Nerve Stimulations (TENS) on venous ulcers. A single-blinded, randomized, and controlled trial was done successfully. Sixty venous ulcer patients were divided randomly into three groups; Group (A): control group, Group(B): High-TENS group, and Group(C): Low-TENS group. Group (A), contains twenty participants who received routine medical care and dressing. As for group (B), includes twenty participants who obtained high-frequency TENS; Frequency (80-120) HZ, Intensity (15 - 30 amp), Pulse duration 250 Micro sec, 60 min per session with routine medical care and dressing. The third group (c) L-TENS, encompasses twenty participants who received low-frequency TENS (1-5) HZ; Intensity (30 -80 amp), Pulse duration 250 Micro sec, 60 min per session with routine medical care and dressing. All the participants were examined before and after two months of intervention; four weeks (post1), then after eight weeks (post2). Participants were examined by using (image j) to measure the ulcer area. Saline was used for measuring the ulcer volume, and a visual analog scale was adopted to evaluate pain. After drawing a comparison among the three groups after four weeks and after eight weeks of treatment, a statistically significant decrease (P <0.05) in wound surface area, wound volume, and pain in favor of L-TENS was noticed. It has been found that L- TENS is more effective than H -TENS and is highly recommended in the treatment protocol for such debilitating conditions.

Cost analysis of negative-pressure wound therapy versus standard treatment of acute conflict-related extremity wounds within a randomized controlled trial

Background

Clinical outcomes after negative-pressure wound therapy (NPWT) and standard treatment of conflict-related extremity wounds are similar. In resource-limited settings, cost affects the choice of treatment. We aimed to estimate treatment-related costs of NPWT in comparison with standard treatment for conflict-related extremity wounds.

Methods

We derived outcome data from a randomized, controlled superiority trial that enrolled adult (≥ 18 years) patients with acute (≤ 72 h) conflict-related extremity wounds at two civilian hospitals in Jordan and Iraq. Primary endpoint was mean treatment-related healthcare costs (adjusted to 2019 US dollars).

Results

Patients were enrolled from June 9, 2015, to October 24, 2018. A total of 165 patients (155 men [93.9%]; 10 women [6.1%]; and median [IQR] age, 28 [21–34] years) were included in the analysis. The cost per patient treated with NPWT was $142 above that of standard treatment. Overall, results were robust in a sensitivity analysis.

Conclusions

With similar clinical outcomes compared to standard care, our results do not support the use of NPWT in routine treatment of conflict-related extremity wounds at civilian hospitals in resource scarce settings.

Trial registration NCT02444598.

Negative-pressure wound therapy is effective for peritoneal dialysis catheter exit-site management in the early postoperative period

Peritoneal dialysis (PD) catheter exit-site care is critically important for the prevention of catheter-related infections (CRIs) and subsequent peritonitis. The postoperative management of the site is particularly essential because it has an open wound that is always adjacent to a PD catheter tube. This study aimed to examine the effectiveness of negative-pressure wound therapy (NPWT) for postoperative PD catheter exit sites. Thirty patients with end-stage renal disease who underwent simultaneous PD catheter insertion and exit-site formation were randomly assigned to receive NPWT (NPWT group) or conventional dressing (non-NPWT group) for the first seven postoperative days. The exit-site scores on the seventh postoperative day was lower in the NPWT group than in the non-NPWT group (p = 0.0049). Analysis of variance F statistic for the effect of NPWT over 180 days was highly significant (11.482595, p = 0.007). There were no statistically significant differences between the time to first CRI and PD-related peritonitis between the two groups. There was one case of CRI with relapsing peritonitis and catheter loss in the non-NPWT group. These findings demonstrate the association between NPWT and low exit-site score. NPWT can be recommended for the management of PD catheter exit sites in the early postoperative period.

Roles of Oxidative Stress and Raftlin in Wound Healing Under Negative-Pressure Wound Therapy

Background

Negative-pressure wound therapy (NPWT) is an effective way to promote wound healing. However, its mechanisms have not been investigated thoroughly. Growing evidence suggests that oxidative stress and Raftlin levels play important roles in wound healing. However, whether NPWT promotes wound healing through this mechanism remains unclear.

Purpose

Our study focuses on the different levels of oxidative stress and antioxidant response between wounds treated by NPWT and routine dressing change. The objective of this study was to measure the differences in Raftlin levels between the two groups, which is a new biomarker related to wound healing.

Methods

We divided 48 male Sprague-Dawley rats with identical full-thickness skin defects into two groups. At specific times (0, 3, 5, 7, 9, 11, and 13 days after surgery), wound tissue samples were obtained for immunohistochemistry and biochemical analysis. The expression of Raftlin and levels of oxidative stress, including malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured by biochemical analysis. Wound-healing times were also compared.

Results

In the NPWT group, MDA levels were significantly decreased on days 3, 5, and 7. Furthermore, the expressions of SOD and CAT were significantly reduced on days 3 and 5. Our data also revealed that Raftlin was significantly upregulated across the whole period of wound healing. Moreover, wound healing in the NPWT group was significantly more rapid (16 days on average) than in the control group (24 days on average). On day 13 post surgery, the wound-healing percentage in the NPWT group was 91%, while that in the control group was 48%.

Conclusion

NPWT may promote wound healing by upregulating Raftlin and inhibiting oxidative stress levels.

Venous Leg Ulcers: Advanced Therapies and New Technologies

The prevalence of venous leg ulcers (VLUs) differs between 1.5% and 3% in the general population. The challenge in treating VLUs is common recurrence. Moreover, VLUs can be resistant to healing, despite appropriate treatment. In these cases, advanced wound therapies should be considered. The number of new technologies, applied in VLUs treatment, has increased in the last years. These therapies include biophysical interventions such as ultrasound therapy, electrical stimulations, electromagnetic therapy, or phototherapy. Furthermore, stem cell therapies, biologic skin equivalents, platelet-rich plasma therapy, oxygen therapies, anti-TNF therapy, or negative pressure wound therapy are advanced venous ulcer therapeutic methods that may support the standard of care. Medical devices, such as a muscle pump activator, or intermittent pneumatic compression device, may be especially useful for specific subgroups of patients suffering from VLUs. Some of the above-mentioned technologies require broader evidence of clinical efficacy and are still considered experimental therapies in dermatology.

Consensus on the diagnosis and management of chronic leg ulcers - Brazilian Society of Dermatology

BACKGROUND

Chronic leg ulcers affect a large portion of the adult population and cause a significant social and economic impact, related to outpatient and hospital care, absence from work, social security expenses, and reduced quality of life. The correct diagnosis and therapeutic approach are essential for a favorable evolution.

OBJECTIVE

To gather the experience of Brazilian dermatologists, reviewing the specialized literature to prepare recommendations for the diagnosis and treatment of the main types of chronic leg ulcers.

METHODS

Seven specialists from six university centers with experience in chronic leg ulcers were appointed by the Brazilian Society of Dermatology to reach a consensus on the diagnosis and therapeutic management of these ulcers. Based on the adapted DELPHI methodology, relevant elements were considered in the diagnosis and treatment of chronic leg ulcers of the most common causes; then, the recent literature was analyzed using the best scientific evidence.

RESULTS

The following themes were defined as relevant for this consensus - the most prevalent differential etiological diagnoses of chronic leg ulcers (venous, arterial, neuropathic, and hypertensive ulcers), as well as the management of each one. It also included the topic of general principles for local management, common to chronic ulcers, regardless of the etiology.

CONCLUSION

This consensus addressed the main etiologies of chronic leg ulcers and their management based on scientific evidence to assist dermatologists and other health professionals and benefit the greatest number of patients with this condition.

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.

Kikuhime Device in the Management of Venous Leg Ulcers

The effectiveness of compression therapy in the treatment of venous leg ulcers has been confirmed in many scientific studies. The healing process depends on many of its parameters, such as the type of compression bandages, their elastic properties and sub-bandage pressure. However, there is no standard protocol that would ensure success for all patients. A pressure of about 83 mmHg provides complete compression for both superficial and deep veins; however, applying compression bandages under such high pressure is a difficult task, even for experienced therapists. Here, we present the case of a 61-year-old woman with approximately 2.5-year-old venous ulcer in her left leg due to chronic venous insufficiency (CVI). Our study aimed to show that routine pressure control at each bandage renewal using the Kikuhime device, as well as their twice daily application in the first week of therapy reduced the healing time of a venous leg ulcer with an area of about 20 cm² to four weeks.

ALGINATE versus NPWT in the Preparation of Surgical Excisions for an STSG: ATEC Trial

Supplemental Digital Content is available in the text.

A calcium alginate dressing (ALGINATE) and negative pressure wound therapy (NPWT) are frequently used to treat wounds which heal by secondary intention. This trial compared the healing efficacy and safety of these 2 treatments.

Leg Ulcers in Sickle-Cell Disease: Treatment Update

Significance: Sickle-cell leg ulcers (SCLUs) are a severe, chronic, and recurrent complication of sickle-cell disease (SCD). There are no official recommendations for treatment. Recent Advances: Only a few studies with a high level of evidence have been conducted to evaluate treatment of SCLUs. However, several studies have been conducted with a high level of evidence to evaluate the efficacy of treatments in venous leg ulcers, and SCLUs could benefit from these treatments, especially when a venous incompetence or an edema is associated. Pathophysiology of SCLUs includes a vasculopathy related to chronic hemolysis and an endothelial dysfunction, which could be therapeutic approaches to SCLU treatment. Critical Issues: Therapeutic approaches to SCLUs can target SCD on the one hand and skin healing and associated aggravating factors on the other. A review of the literature found only case series and six randomized controlled trials; some offered encouraging results, but most had serious biases. Clinical trials specifically targeting SCLUs are difficult to realize because of the small number of affected patients, in comparison with patients with leg ulcers from other causes. Future Direction: Treating SCLUs remains a challenge. Data in the literature are currently insufficient to offer clear treatment guidelines because of several biases in controlled studies. New studies are under way to assess the efficacy of topical treatments and describe the microbiome of SCLUs. Prevention of SCLU recurrence should be assessed in future clinical trials because the high risk of recurrence is an unsolved critical issue.

Evaluating complications in below-knee skin cancer surgery after introduction of preoperative appointments: A 2-year retrospective cohort study

Below-knee dermatological surgery has a high risk of complications such as wound infection, bleeding, and necrosis. In this study, we evaluated the impact of preoperative appointments on complication risks. We searched the medical records of the Helsinki University Central Hospital (HUS) Dermatosurgery unit for all below-knee surgeries during 2016, when no preoperative nurse appointments were carried out, and compared it with 2018, when preoperative appointments for risk patients were introduced. The study included 187 patients in 2016 and 179 patients in 2018, of whom 68 (about one third) attended preoperative appointments. At the appointments, risk factors were evaluated, and compression therapy was introduced when possible. The results show complication rates of 13.4% in 2016 vs 10.1% in 2018 (P = .33), despite significantly higher risks in the 2018 patient group. The odds ratio for complications in appointment attendees vs non-attendees was reduced after adjustments to 0.58; however, this was insignificant (P = .47). The odds of complications for skin grafts were considerably higher: 11.33 vs other surgery techniques (P = .00). In conclusion, the introduction of preoperative appointments appeared to reduce complications in below-knee surgery. For graft reconstructions, complication risk is high, even with carefully planned pre- and postoperative care. Further studies are needed to evaluate preventable risk factors of below-knee graft reconstructions.

Development of a Minimum Data Set Registry for Chronic Venous Insufficiency of the Lower Limbs

The purpose of this study was to develop a minimum data set (MDS) registry for the prevention, diagnosis and treatment of chronic venous insufficiency (CVI) of the lower limbs. We designed the instrument in two phases, comprising a literature review and an e-Delphi study to validate the content. We obtained a total of 39 documents that we used to develop a registry with 125 items grouped in 7 categories, as follows: Patient examination, venous disease assessment methods, diagnostic tests to confirm the disease, ulcer assessment, treatments to manage the disease at all its stages, patient quality of life, and patient health education. The instrument content was validated by 25 experts, 88% of whom were primary healthcare and hospital nurses and 84% had more than 10 years' experience in wound care. Using a two-round Delphi approach, we reduced the number of items in the MDS-CVI to 106 items. The categories remained unchanged. We developed an MDS for CVI with seven categories to assist healthcare professionals in the prevention, early detection, and treatment history of CVI. This tool will allow the creation of a registry in the primary care setting to monitor the venous health state of the population.

A prospective, randomized, controlled clinical trial on the efficacy of a single-use negative pressure wound therapy system, compared to traditional negative pressure wound therapy in the treatment of chronic ulcers of the lower extremities

Multicenter, phase‐4, randomized, comparative‐efficacy study in patients with VLUs or DFUs comparing for noninferiority the percentage change in target ulcer dimensions (area, depth, and volume) a single‐use negative pressure wound therapy (s‐NPWT) system versus traditional NPWT (t‐NPWT) over a 12‐week treatment period or up to confirmed healing. Baseline values were taken at the randomization visit. Randomized by wound type and size, 164 patients with non‐infected DFUs and VLUs were included. The ITT population was composed of 161 patients (101 with VLUs, 60 with DFUs) and 115 patients completed follow‐up (64 in the s‐NPWT group and 51 in the t‐NPWT group) (PP population). The average age for all patients was 61.5 years, 36.6% were women, and treatment groups were statistically similar at baseline. Primary endpoint analyses on wound area reduction demonstrated statistically significant reduction in favor of s‐NPWT (p = 0.003) for the PP population and for the ITT population (p < 0.001). Changes in wound depth (p = 0.018) and volume (p = 0.013) were also better with s‐NPWT. Faster wound closure was observed with s‐NPWT (Cox Proportional Hazards ratio (0.493 (0.273, 0.891); p = 0.019) in the ITT population. Wound closure occurred in 45% of patients in the s‐NPWT group vs. 22.2% of patients in the t‐NPWT group (p = 0.002). Median estimate of the time to wound closure was 77 days for s‐NPWT. No estimate could be provided for t‐NPWT due to the low number of patients achieving wound closure. Device‐related AEs were more frequent in the t‐NPWT group (41 AEs from 29 patients) than in the s‐NPWT group (16 AEs from 12 patients). The s‐NPWT system met noninferiority and achieved statistical superiority vs. t‐NPWT in terms of wound progression toward healing over the treatment period. When NPWT is being considered for the management of challenging VLUs and DFUs, s‐NPWT should be considered a first choice over other types of NPWT.

The discovery and development of topical medicines for wound healing

INTRODUCTION

Chronic, nonhealing skin wounds claim >3% of the health-care budget in industrialized countries, and the incidence is rising. Currently, two parallel trends influence innovations within the field of wound healing: the need to reduce spread of antibiotic resistance and the emerging use of health economy and value-based models. Areas covered: This review focuses on the discovery of drug candidates and development of treatments aiming to enhance wound healing in the heterogeneous group of patients with nonhealing wounds. Expert opinion: Nonhealing wounds are multifaceted and recognized as difficult indications. The majority of products currently in use are medical device dressings, or concepts of negative pressure or hyperbaric oxygen treatment. Global best practice guidelines for the treatment of diabetic foot ulcers recommend debridement, redressing, as well as infection control, and are critical to the lack of coherent clinical evidence for many approved products in active wound care. To accelerate wound healing, there is an emerging trend toward biologics, gene therapy, and novel concepts for drug delivery in research and in the pipeline for clinical trials. Scientific delineation of the therapeutic mechanism of action is, in our opinion, vital for clinical trial success and for an increased fraction of medical products in the pharmaceutical pipeline.

MicroRNA-126: a promising biomarker for angiogenesis of diabetic wounds treated with negative pressure wound therapy

BACKGROUND

Negative pressure wound therapy represents an effective therapy to treat nonhealing diabetic wounds by promoting angiogenesis, of which the mechanism hasn't been investigated thoroughly. Growing evidence suggests that miRNAs hold great potential to be clinical biomarkers, and miR-126 is an essential angiogenesis regulator in diabetic wound repair.

PURPOSE

Our study aims to explore the effect of NPWT on the expression of miR-126 in the wound tissue and plasma of diabetic rat models and the association between circulating miR-126 and two quantitative indexes of angiogenesis.

METHODS

Full-thickness excisional wounds were created on the back of diabetic rats. Measure the wound closure and collect the wound tissue and blood for H&E, immunohistochemistry, Western blot and RT-PCR. Here we demonstrated that significantly increased capillary density and arteriolar density in the NPWT group at each specified time-point.

RESULTS

In the NPWT group, miR-126 expression was significantly increased on days 3, 5, 7, and 9 (P<0.05). Furthermore, statistically significant increases in VEGF mRNA and protein expression and p-ERK expression, as well as decreased SPRED1 expression, were noted upon treatment with NPWT on day 9. Our data revealed that miR-126 expression in the wound and plasma was significantly associated (P<0.05). Moreover, a positive correlation was also detected between increased levels of circulating miR-126 and arteriolar density, as well as capillary density (P<0.05).

CONCLUSION

The study suggested that miR-126 was upregulated by NPWT and could represent a promising monitoring tool for angiogenesis in diabetic wounds treated with NPWT.

Mechanisms of Action of Instillation and Dwell Negative Pressure Wound Therapy with Case Reports of Clinical Applications

Negative pressure wound therapy (NPWT) has revolutionized the care of complex wounds since 1997. The addition of instillation (NPWTi-d) adds several potential benefits and challenges to clinicians dealing with complex wounds in a hospital setting.

We surveyed the literature regarding the mechanism of action of these devices and reviewed our clinical experience to date.

Potential mechanisms of action include the removal of microorganisms from the wound surface, dilution of cytotoxic molecules, upregulation of angiogenesis pathways, and maintenance of a moist wound environment. As we have extended our use of these devices to more complex wounds, we have taken advantage of and observed potential mechanisms of action, including facilitated removal of microorganisms, dilution of inflammatory and cytotoxic macromolecules, additional wound hydration, and enhanced angiogenesis through an intermittent application of NPWT. We have also observed complications, including bleeding, loss of a seal along the wound, and pain.

NPWTi-d provides additional options for clinicians caring for complex wounds with favorable responses in wounds with significant contamination and those with poor inherent vascularity. Further studies to clarify the mechanisms of action, better define the wound types that would benefit, and techniques to manage complications using this device should further advance this field.

Negative pressure wound therapy for open traumatic wounds

BACKGROUND

Traumatic wounds (wounds caused by injury) range from abrasions and minor skin incisions or tears, to wounds with extensive tissue damage or loss as well as damage to bone and internal organs. Two key types of traumatic wounds considered in this review are those that damage soft tissue only and those that involve a broken bone, that is, open fractures. In some cases these wounds are left open and negative pressure wound therapy (NPWT) is used as a treatment. This medical device involves the application of a wound dressing through which negative pressure is applied and tissue fluid drawn away from the area. The treatment aims to support wound management, to prepare wounds for further surgery, to reduce the risk of infection and potentially to reduce time to healing (with or without surgical intervention). There are no systematic reviews assessing the effectiveness of NPWT for traumatic wounds.

OBJECTIVES

To assess the effects of NPWT for treating open traumatic wounds in people managed in any care setting.

SEARCH METHODS

In June 2018 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 as well as 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.

SELECTION CRITERIA

Published and unpublished randomised controlled trials that used NPWT for open traumatic wounds involving either open fractures or soft tissue wounds. Wound healing, wound infection and adverse events were our primary outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible studies, extracted data, carried out a 'Risk of bias' assessment and rated the certainty of the evidence. Data were presented and analysed separately for open fracture wounds and other open traumatic wounds (not involving a broken bone).

MAIN RESULTS

Seven RCTs (1377 participants recruited) met the inclusion criteria of this review. Study sample sizes ranged from 40 to 586 participants. One study had three arms, which were all included in the review. Six studies compared NPWT at 125 mmHg with standard care: one of these studies did not report any relevant outcome data. One further study compared NPWT at 75 mmHg with standard care and NPWT 125mmHg with NPWT 75 mmHg.Open fracture wounds (four studies all comparing NPWT 125 mmHg with standard care)One study (460 participants) comparing NPWT 125 mmHg with standard care reported the proportions of wounds healed in each arm. At six weeks there was no clear difference between groups in the number of participants with a healed, open fracture wound: risk ratio (RR) 1.01 (95% confidence interval (CI) 0.81 to 1.27); moderate-certainty evidence, downgraded for imprecision.We pooled data on wound infection from four studies (596 participants). Follow-up varied between studies but was approximately 30 days. On average, it is uncertain whether NPWT at 125 mmHg reduces the risk of wound infection compared with standard care (RR 0.48, 95% CI 0.20 to 1.13; I2 = 56%); very low-certainty evidence downgraded for risk of bias, inconsistency and imprecision.Data from one study shows that there is probably no clear difference in health-related quality of life between participants treated with NPWT 125 mmHg and those treated with standard wound care (EQ-5D utility scores mean difference (MD) -0.01, 95% CI -0.08 to 0.06; 364 participants, moderate-certainty evidence; physical component summary score of the short-form 12 instrument MD -0.50, 95% CI -4.08 to 3.08; 329 participants; low-certainty evidence downgraded for imprecision).Moderate-certainty evidence from one trial (460 participants) suggests that NPWT is unlikely to be a cost-effective treatment for open fractures in the UK. On average, NPWT was more costly and conferred few additional quality-adjusted life years (QALYs) when compared with standard care. The incremental cost-effectiveness ratio was GBP 267,910 and NPWT was shown to be unlikely to be cost effective at a range of cost-per-QALYs thresholds. We downgraded the certainty of the evidence for imprecision.Other open traumatic wounds (two studies, one comparing NPWT 125 mmHg with standard care and a three-arm study comparing NPWT 125 mmHg, NPWT 75 mmHg and standard care)Pooled data from two studies (509 participants) suggests no clear difference in risk of wound infection between open traumatic wounds treated with NPWT at 125 mmHg or standard care (RR 0.61, 95% CI 0.31 to 1.18); low-certainty evidence downgraded for risk of bias and imprecision.One trial with 463 participants compared NPWT at 75 mmHg with standard care and with NPWT at 125 mmHg. Data on wound infection were reported for each comparison. It is uncertain if there is a difference in risk of wound infection between NPWT 75 mmHg and standard care (RR 0.44, 95% CI 0.17 to 1.10; 463 participants) and uncertain if there is a difference in risk of wound infection between NPWT 75 mmHg and 125 mmHg (RR 1.04, 95% CI 0.31 to 3.51; 251 participants. We downgraded the certainty of the evidence for risk of bias and imprecision.

AUTHORS' CONCLUSIONS

There is moderate-certainty evidence for no clear difference between NPWT and standard care on the proportion of wounds healed at six weeks for open fracture wounds. There is moderate-certainty evidence that NPWT is not a cost-effective treatment for open fracture wounds. Moderate-certainty evidence means that the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. It is uncertain whether there is a difference in risk of wound infection, adverse events, time to closure or coverage surgery, pain or health-related quality of life between NPWT and standard care for any type of open traumatic wound.

Intermittent mild negative pressure applied to the lower limb in patients with spinal cord injury and chronic lower limb ulcers: a crossover pilot study

STUDY DESIGN

Randomized, assessor-blinded crossover pilot study.

OBJECTIVES

To explore the use of an intermittent negative pressure (INP) device for home use in addition to standard wound care (SWC) for patients with spinal cord injury (SCI) and chronic leg and foot ulcers before conducting a superiority trial.

SETTING

Patient homes and outpatient clinic.

METHODS

A 16-week crossover trial on 9 SCI patients (median age: 57 years, interquartile range [IQR] 52-66), with leg ulcers for 52 of weeks (IQR: 12-82) duration. At baseline, patients were allocated to treatment with INP + SWC or SWC alone. After 8 weeks, the ulcers were evaluated. To assess protocol adherence, the patients were then crossed over to the other group and were evaluated again after another 8 weeks. Lower limb INP treatment consisted of an airtight pressure chamber connected to an INP generator (alternating 10 s -40mmHg/7 s atmospheric pressure) used 2 h/day at home. Ulcer healing was assessed using a photographic wound assessment tool (PWAT) and by measuring changes in wound surface area (WSA).

RESULTS

Seven of nine recruited patients adhered to a median of 90% (IQR: 80-96) of the prescribed 8-week INP-protocol, and completed the study without side effects. PWAT improvement was observed in 4/4 patients for INP + SWC vs. 2/5 patients for SWC alone (P = 0.13). WSA improved in 3/4 patients allocated to INP + SWC vs. 3/5 patients in SWC alone (P = 0.72).

CONCLUSIONS

INP can be used as a home-based treatment for patients with SCI, and its efficacy should be tested in an adequately sized, preferably multicenter randomized trial.

The effects of intermittent negative pressure on the lower extremities' peripheral circulation and wound healing in four patients with lower limb ischemia and hard-to-heal leg ulcers: a case report

Peripheral circulation is severely compromised in the advanced stages of peripheral arterial disease. Recently, it was shown that the application of -40 mmHg intermittent negative pressure (INP) to the lower leg and foot enhances macro- and microcirculation in healthy volunteers. In this case report, we describe the effects of INP treatment on four patients with lower limb ischemia and hard-to-heal leg and foot ulcers. We hypothesized that INP therapy may have beneficial hemodynamic and clinical effects in the patients. Four patients (age range: 61-79 years) with hard-to-heal leg and foot ulcers (6-24 months) and ankle-brachial pressure indices of ≤0.60 on the affected side were included. They were treated with an 8-week intervention period of -40 mmHg INP (10 sec negative pressure and 7 sec atmospheric pressure) on the lower limbs. A custom-made vacuum chamber was used to apply INP to the affected lower leg and foot for 2 h per day. After 8 weeks of INP therapy, one ulcer healed completely, while the other three ulcers were almost completely healed. These cases suggest that INP may facilitate wound healing. The theoretical foundation is that INP assists wound healing by improving blood flow to the small blood vessels in the affected limb, increasing the flow of oxygen and nutrients to the cells.

Wound bed preparation: TIME for an update

While the overwhelming majority of wounds heal rapidly, a significant proportion fail to progress through the wound-healing process. These resultant chronic wounds cause considerable morbidity and are costly to treat. Wound bed preparation, summarised by the TIME (Tissue, Inflammation/infection, Moisture imbalance, Epithelial edge advancement) concept, is a systematic approach for assessing chronic wounds. Each of these components needs to be addressed and optimised to improve the chances of successful wound closure. We present an up-to-date literature review of the most important recent aspects of wound bed preparation. While there are many novel therapies that are available to the treating clinician, often, there are limited data on which to assess their clinical value, and a lack of appreciation for adequate wound bed preparation needed before expensive therapy is used to heal a wound.

Treatment of anticoagulated patients with negative pressure wound therapy

There is a paucity of evidence surrounding the use of negative pressure wound therapy (NPWT) in patients receiving anticoagulant medication. Guidelines generally recommend caution regarding the use of NPWT in anticoagulated patients in general, but areas of particular risk are frequently not highlighted. The US Food and Drug Authority (FDA) reported six mortalities between 2009 and 2011 in patients receiving NPWT. These mortalities were associated with the use of NPWT over vascular graft sites. The coagulation status of these patients was not reported. It is the authors' recommendation that guidelines regarding the use of NPWT in anticoagulated patients highlight specific clinical situations of risk, although there is insufficient evidence to support the avoidance of NPWT in anticoagulated patients in general.

Negative Pressure Wound Therapy in Maxillofacial Applications

Negative pressure wound therapy has greatly advanced the field of wound healing for nearly two decades, by providing a robust surgical adjunct technique for accelerating wound closure in acute and chronic wounds. However, the application of negative pressure wound therapy in maxillofacial applications has been relatively under utilized as a result of the physical articulations and contours of the head and neck that make it challenging to obtain an airtight seal for different negative pressure wound therapy systems. Adapting negative pressure wound therapies for maxillofacial applications could yield significant enhancement of wound closure in maxillofacial applications. The current review summarizes the basic science underlying negative pressure wound therapy, as well as specific maxillofacial procedures that could benefit from negative pressure wound therapy.