Use of Indigenously Made Negative-Pressure Wound Therapy System for Patients with Diabetic Foot

Use of injectable acellular dermal matrix combined with negative pressure wound therapy in open diabetic foot amputation

Objective:

Skin grafts after negative pressure wound therapy (NPWT) and acellular dermal matrix (ADM) usage have both been useful for treating diabetic foot amputation. We hypothesised that injectable ADM combined with NPWT would be more useful than NPWT only for healing after amputation in patients with diabetic foot ulcers (DFUs). The aim of this study was to investigate the clinical outcomes of injectable ADM combined with NPWT in patients with DFU who have undergone amputation.

Method:

This retrospective study reviewed patients with infected DFUs who were administered NPWT. Patients were divided into two groups: Group 1 included patients who were treated with NPWT only, while Group 2 included patients who were treated with injectable ADM combined with NPWT. Clinical results including the number of NPWT dressing changes, wound healing duration, and full-thickness skin graft (FTSG) incident rate between the two groups were compared.

Results:

A total of 41 patients took part in the study (Group 1=20, Group 2=21). The mean number of NPWT dressing changes was significantly lower in Group 2 (8.71±3.77) than in Group 1 (13.90±5.62) (p=0.001). Mean wound healing period was shorter in Group 2 (3.17±1.36 weeks) than in Group 1 (5.47±1.68 weeks) (p=0.001). Finally, the rate of patients who underwent FTSG for complete wound closure was 85% in Group 1, whereas it was only 14.3% in Group 2.

Conclusion:

In this study, the use of injectable ADM combined with NPWT in patients with DFU who underwent amputation favoured complete wound healing, without the need to resort to the use of skin grafts.

NPWT in diabetic foot wounds-a systematic review and meta-analysis of observational studies

PURPOSE

Negative-pressure wound therapy (NPWT) is an adjunct modality in diabetic foot ulcerations (DFUs). Randomized controlled trials (RCTs) have shown its advantage over standard approaches; however, data from observational studies remain scarce.We performed a systematic review of observational non-RCTs evaluating NPWT efficacy and safety in patients with DFU.

METHODS

Electronic databases were searched for observational studies involving NPWT. The results of single-arm studies were presented as percentages of patients with the outcome of interest. A meta-analysis of comparative studies provided point estimates of outcomes. Continuous outcomes were reported as either weighted or standardized mean differences and dichotomous data as relative risks (RR).

RESULTS

The search identified 16 relevant observational studies, 12 single-arm, and 4 comparative, reporting on a total of 18,449 patients with DFU, of whom 1882 were managed with NPWT. In the NPWT-treated patients, ulcers were larger (average size range 6.6-27.9 cm²), as compared with controls (≤3 cm²). The pooled results showed healing and major amputation in 51% and 5% of NPWT patients, respectively. The meta-analysis of comparative studies revealed lower risk of major amputation [RR = 0.23 (0.07; 0.80)] in NPWT-treated patients. The pooled results for healing rate and risk of any amputation were inconclusive due to large between-study heterogeneity. Overall, 6 deaths out of 158 patients were reported, none of them related to NPWT. Serious adverse events occurred in 6% of patients on NPWT.

CONCLUSIONS

This systematic review of observational studies provided supportive evidence that NWPT is an efficient and safe adjunct treatment in the management of DFUs.

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.

The efficacy of negative pressure wound therapy for diabetic foot ulcers: A systematised review

AIM

This review investigated the current state of knowledge on negative pressure wound therapy (NPWT) used to treat diabetic foot ulceration (DFU), its clinical effectiveness and any current issues in the research. NICE have recommended research into the clinical effectiveness of different dressing types for DFUs since 2015.

METHODS

A systematic search of the British Nursing Index, CINAHL, Cochrane Central and PubMed was undertaken. Only primary studies were included and studies investigating a combination of NPWT and other therapies were excluded. All the included studies were published in English between 2008 and 2018 and were peer reviewed.

RESULTS

The search yielded seven studies for inclusion in the qualitative analysis. The studies included a variety of methodologies specifically; 3 randomized controlled trials, 2 case series', 1 non-controlled trial and 1 randomized case-control study. Three main themes were identified and formed the focus of the qualitative synthesis.

DISCUSSION

All the included studies reported that NPWT led to better clinical outcomes when compared to standard treatment. However, the studies had numerous methodological flaws such as the absence of validated tools for the measurement of outcomes such as wound area and depth; a lack of statistical power calculations to determine adequate sample sizes or the significance of outcome measures. Additionally, there was little consistency in the pressures used for the NPWT devices. Finally, many of the controlled trials did not conform to the standard of reporting trials stipulated by the CONSORT statement.

An inexpensive method of negative pressure wound therapy for extremities

Negative pressure wound therapy (NPWT) is an established method for the faster wound healing of chronic non-healing wounds. It is also used for laparostomy wounds and healing of split skin grafts. The commercially available machine and the consumables for NPWT are very expensive and economically not feasible in developing and underdeveloped countries. So, we devised a NPWT system for wounds of the extremity using inexpensive, readily available materials in any hospital. The materials used are sterile glove, autoclaved sponge, Foley catheter, and a wall suction unit. The sponge was placed over the wound, and a sterile glove was pulled over it. A Foley catheter was placed over the sponge and taken out through one of the fingers of the glove. Adhesive plaster was used to air-seal the glove. The Foley catheter was fixed with silk ties and connected to wall suction. Granulation and wound healing was faster in this system. This system was safe and inexpensive for the treatment of wounds of the extremity.