An article was published in Wound Repair and Regeneration on “Comparative effectiveness of mechanically and electrically powered negative pressure wound therapy devices: A multicenter randomized controlled trial” in January 2012 by DG Armstrong, WA Marston, AM Reyzelman, and RS Kirsner. This was a 17-center prospective, randomized controlled clinical trial designed to evaluate the relative impact on wound closure using the “mechanically powered” Smart Negative Pressure (SNaP) Wound Care System (Spiracur, Inc.) vs. the “electrically powered” Vacuum-Assisted Closure (VAC) Therapy System (KCI, San Antonio, TX). One hundred thirty-two (132) patients were enrolled with non-infected, non-ischemic, non-plantar lower extremity diabetic and venous wounds. Eighty-three patients (n = 41 SNaP, n = 42 VAC) completed the study with either healing or 16 weeks of therapy. The study provides evidence that treatment of wounds using a disposable NPWT device (SNaP System) compared to a traditional NPWT device (VAC System) have similar results but have less impact on the patient’s quality of life. Potential conflict of interest is that this study was sponsored by Spiracur Inc. and two of the authors received research funding from both Spiracur (SNaP device) and K.C.I. (VAC device). The quality of evidence is low; the strength of recommendation is weak.
“Comparison of high-frequency and MIST ultrasound therapy for the healing of venous leg ulcers” by Beheshti A, Shafigh Y, Parsa H, and Zangivand AA was published in the 2014 Advances in Clinical and Experimental Medicine. The aim of the year-long randomized controlled study of 90 patients was to analyze the effect of standard ulcer care alone (compression bandages) with high-frequency ultrasound (HFU) and MIST ultrasound therapy (US) on venous leg ulcers (VLUs). The patients were chosen from patients with VLUs who had received wound care at the hospital outpatient vascular clinic of Shahid Rajaii Hospital. Patients were instructed to contact the clinic monthly and recurrence of VLUs was recorded for six months after complete wound healing. Study results showed no significant differences in recurrence between groups during a six-month follow-up after complete wound healing. All VLUs in the study healed within one year. Recurrence was observed in four cases in the standard group (13.3%); two cases in the HFU group and two cases in the MIST US group (6.6%). The authors stated their results were lower than similar studies but state the 6-month follow-up is very short to truly decide about the potential of prevention of recurrence in patients treated with US therapy. Mean age was 58.5 years (SD 11.6 years).The authors concluded the study showed significant effectiveness of ultrasound therapy; especially MIST therapy, in wound healing as an adjuvant therapy. They noted differences between the two ultrasound therapy groups were not statistically significant. Exclusion criteria were listed. The design of this study presents limitations including selection bias. The report states the patients were randomized but suggests the study may not have been blinded. Other limitations to this study were a small sample size and inconsistency across studies when comparisons were made. The authors compare the results of their study to other studies of different sample size, different ages, unknown co-morbidities and different wound types. The authors remark that additional work on cost-effectiveness outcomes and planning are greatly needed for the future studies. Note: This study was conducted outside the U.S. and does not largely represent the Medicare population. The quality of evidence is low; the strength of recommendation is weak.
The 2007 Journal of Palliative Medicine article by Ferris, Al Khateib, and Fromantin, “Palliative wound care: managing chronic wounds across life’s continuum: a consensus statement from the International Palliative Wound Care Initiative,” is a consensus statement which recognizes that while most chronic wounds will eventually heal if managed appropriately, some will not. In patients with non-healable wounds, therapies that aim to heal the wound may not be in anyone’s best interest. The Initiative recognizes that the expertise and skills in palliative wound care can improve the quality of life of all individuals living with or affected by healing and non-healing chronic wounds and is guided by the philosophy that the opportunity exists to negotiate personalized goals of care to optimize quality of life through an interdisciplinary approach to care. Quality of evidence is low. Strength of recommendation is weak.
The 2015 “Debridement for venous leg ulcers (Review)” by Gethin, Cowman, and Kolbach is a Cochrane Database Systematic Review done through search of a wide range of electronic data bases for randomized control trials (RCTs), either published or unpublished, which compared methods of debridement or compared debridement with no debridement. Ten RCTs were identified involving a total of 715 participants. These studies were selected independently by two review authors who completed all study selection, data extraction and assessment of trial quality; resolution of disagreements was completed by a third review author. Eight RCTs evaluated autolytic debridement and included the following agents or dressings: biocellulose wound dressing (BWD), non-adherent dressing, honey gel, hydrogel (gel formula), hydrofibre dressing, hydrocolloid dressings, dextranomer beads, Edinburgh University Solution of Lime (EUSOL) and paraffin gauze. Two RCTs reported enzymatic preparations and one evaluated biosurgical debridement. No RCTs evaluated surgical, sharp or mechanical methods of debridement, or debridement versus no debridement. The systematic review had the following weaknesses: study results were presented in a narrative form, small populations, heterogeneity of outcomes, and lack of comparability across trials, inconsistent methodology across trials and there was a high risk of bias since most of the RCTs had high risk of bias. The authors conclude there is limited evidence to suggest that actively debriding a venous leg ulcer has a clinically significant impact on healing. The overall small number of participants, low number of studies and lack of meta-analysis in this review precludes any strong conclusions of benefit. Comparisons of different autolytic agents (hydrogel versus paraffin gauze; Dextranomer beads versus EUSOL and BWD versus non adherent dressings) and Larvae versus hydrogel all showed statistically significant results for numbers of wounds debrided. Larger trials with follow up to healing are required. The quality of evidence is low; the strength of recommendation is weak.
In 2015, “A Prospective, Randomized, Controlled Trial Comparing the Effects of Noncontact, Low-frequency Ultrasound to Standard Care in Healing Venous Leg Ulcers” was published in Ostomy Wound Management by Gibbons, Orgill, Serena, et al. This article is a prospective, randomized, controlled, multicenter (22 U.S. sites) trial that was conducted to compare percent wound size reduction, proportions healed, pain, and quality-of-life (QOL) outcomes in patients randomized to standard care (SC) alone or SC and 40 kHz noncontact, low-frequency ultrasound (NLFU) treatments 3 times per week for 4 weeks. One hundred twelve (112) eligible participants with documented venous stasis, a VLU greater than 30 days’ duration, measuring 4 cm2 to 50 cm2, and demonstrated arterial flow were enrolled. Of these, 81 (72%) reduced less than 30% in size during the 2-week run-in study phase and were randomized (SC, n = 40; NLFU+SC, n = 41). Median age of participants was 59 years; 83% had multiple complex comorbidities. After 4 weeks of treatment, average wound size reduction was 61.6% ± 28.9 in the NLFU+SC compared to 45% ± 32.5 in the SC group (P = 0.02). Reductions in median (65.7% versus 44.4%, P = 0.02) and absolute wound area (9.0 cm2 versus 4.1 cm2, P = 0.003) as well as pain scores (from 3.0 to 0.6 versus 3.0 to 2.4, P = 0.01) were also significant. NLFU therapy with guideline-defined standard VLU care should be considered for healing VLUs not responding to SC alone. The results of this study warrant further research on barriers to healing and the changes occurring in the tissue of the wound to explore theories that the microenvironment impacts wounds that do not heal despite provision of guideline-defined care. This study was sponsored by Celleration, Inc. The authors consulted on study design, protocol development, and study oversight. The authors remained blinded throughout the study. A limitation of this study was that the investigators and participants were not blinded to treatment group assignment. The study was limited to participant-reported measures such as QOL and VAS pain scores. A second limitation was the treatment groups did not have the same required frequency of treatment visits. Another limitation was that there was a short-term (7-week) follow-up with a final ulcer measurement performed at the last study visit, 11 weeks post randomization. The quality of evidence is low; the strength of recommendation is weak.
In 2004, Gupta, Baharestani, Baranoski, et al. published “Guidelines of Managing Pressure Ulcers with Negative Pressure Wound Therapy” in Advances in Skin & Wound Care. In this article, a consensus panel of experienced wound care clinicians reviewed the mechanism of action and research basis for Negative Pressure Wound Therapy (NPWT). After answering key questions about NPWT, an algorithm was developed to assist clinicians in decision making for use of NPWT with Stage III/IV pressure ulcers. Therapy with NPWT lasted for a mean of 35 days (range: 3-124 days). Panel members believe the role of NPWT as an adjunctive therapy should be validated. The guideline states the numbers should be interpreted cautiously, however, because of discrepancies in methodology. Limitations include multiple studies with variable criteria, and/or with study size, duration, population undefined. Some conclusions are not statistically substantiated. This guideline was limited to “FDA-cleared NPWT device (V.A.C. Therapy System)” and funded by a NPWT manufacturer. The quality of evidence is low; the strength of recommendation is weak.
In 2005, Home Health Care Management & Practice published “Palliative wound care at the end of life” by Hughes, Bakos, O’Mara, et al. This source purports that providing wound care, although often curative, is also palliative. It further states that patients nearing the end of their lives may benefit from the curative aspects of wound care and makes the following assertions. Palliative care supports the health care needs of dying patients by focusing on alleviating symptoms. Although wound care can be both healing and palliative, it can impair the quality of the end of life for the dying if it is done without proper consideration of the patient’s wishes and best interests. Wound care may be optional for dying patients. This article discusses the ethical responsibilities and challenges of providing wound care for surgical wounds, pressure ulcers, and wounds associated with cancer as well as wound care in home health compared to end of life. Quality of evidence is low. Strength of recommendation is weak.
“Use of a Portable, Single-use Negative Pressure Wound Therapy Device in Home Care Patients with Low to Moderately Exuding Wounds: A Case Series” by Hurd, Trueman, and Rossington was published in Ostomy Wound Management in 2014.This case report is an 8-week study to evaluate outcomes of using a single-use NPWT system for the treatment of exuding wounds. Data was retrospectively abstracted from 326 patient medical records. The mean age of patients treated was 57 years (median 61 years, range 17 to 91 years) with mixed etiologies: 53 pressure ulcers, 21 venous leg ulcers, 16 diabetic foot ulcers, 15 traumatic wounds, and 221 surgical wounds. There were 228 with complete wound closure within 8 weeks of treatment. The mean wound area at baseline was 20 cm2 (median 14 cm2, range 0.1–99 cm2). Mean wound volume at baseline was 45 cm3 (median 31 cm3, range 0–269 cm3). At the baseline visit, 180 and 116 patients (91%) had low or moderate levels of exudate, respectively. Although the portable device is indicated for low to moderately exuding wounds, a small number of patients showed scant (12, 4%) and large (18, 6%) levels of exudate, met local protocols for accessing NPWT, and were deemed to be suitable for inclusion in the evaluation in the opinion of the treating physician. The majority of patients (218, 68%) discontinued treatment with portable NPWT as a result of their wound healing within the 8-week evaluation period. The proportion of wounds completely healed during the 8-week evaluation was higher in surgical wounds (167 out of 219, 76%) than in nonsurgical wounds (51 out of 104, 49%); 30 patients (9%) discontinued treatment as a result of the study period ending. An additional 21 patients (7%) discontinued therapy due to hospitalization and nine (3%) due to doctor’s orders. Twenty-six patients (26, 8%) discontinued treatment due to excessive exudate. Excessive exudate was more commonly reported during treatment in nonsurgical than in surgical wounds (14 out of 104 [13%] versus 12 out of 219 [6%], respectively). Device-related reasons for discontinuation were loss of seal (10, 3.1%) and poor compliance (i.e., patient removed device or asked for it to be removed; six [1.9%]). Poor compliance was reported more commonly in nonsurgical wounds, although the numbers remained small (five out of 104, 5%). For five patients, reason for discontinuation was unknown or unreported; there was one death. Healing rates in the portable (disposable) and traditional NPWT groups were similar (approx. 10%/week). The mean reduction in wound area per week was similar in both groups (11% /week, median = 10, range 0–66.7 for portable NPWT compared to 10%/week, median = 9.4, range 1.7–31.7 for conventional NPWT). Patient satisfaction for dressing performance was 97%. Eighty-nine (89) percent who used the conventional NPWT (n=539) had an open surgical wound with moderate or high levels of exudate. The findings of this evaluation suggest the single-use; portable device may redefine access to NPWT for patients with low exudating wounds. The decision to use conventional or portable, single-use NPWT devices should start with wound characteristics such as size and exudate levels. However, other criteria may be taken into account — particularly, the patient’s mobility, lifestyle, and ability to adhere to a treatment regimen. The design of this study presents inherent limitations, including selection bias. This evaluation considered only patients eligible for NPWT treatment according to local protocols, and nurses chose to use portable NPWT on those patients who were most likely to benefit. The comparison with the retrospectively collected data provides some context but no control. In addition to the limitations of evaluating retrospectively collected data, the patient population and wounds previously managed with conventional NPWT were very different from those managed with the portable device. Randomized, controlled clinical studies are needed to compare the portable NPWT device to other treatment modalities indicated for these wounds with respect to wound outcomes, cost-effectiveness, and patient quality of life. The quality of evidence is low; the strength of recommendation is weak.
The Hurd, Rossington, Trueman, et al., comparison article published in Advances in Wound Care in 2017 is a retrospective cohort study consisting of a Canadian institution wide audit of basic, anonymized data derived of records from patients with postsurgical wounds. A total of 1,107 patients were analyzed, 808 of whom were treated with the RENASYS NPWT system (Smith & Nephew) and 299 of whom were treated with the V.A.C. system (KCI, Inc.). The two groups were well matched in terms of their demographics and baseline wound characteristics. The majority of the wounds were postsurgical wounds that had developed complications. The limitations of the study were variable treatment protocols, subjective and objective end points measured and high risk of bias. The findings of this analysis suggest that the RENASYS NPWT system and V.A.C. therapy offer similar levels of performance in the management of challenging wounds. Wound area reductions over the course of the evaluation period were almost identical in both treatment groups and the overall rates of wound closure and the time to achieve predefined treatment goals were comparable. Nanocrystalline silver (ACTICOAT Flex 3) was used successfully as an adjunct to either NPWT system. This retrospective, naturalistic analysis is believed to be the largest case series of NPWT patients presented to date and as such is a valuable complement to the existing evidence base on this therapy. Potential conflicts of interest may include author honorarium and assistance with data interpretation and manuscript preparation from Smith & Nephew. The quality of evidence is moderate; the strength of recommendation is strong.
Krug, Berg, Lee, et al. had “Evidence-Based Recommendations for the Use of Negative Pressure Wound Therapy in Traumatic Wounds and Reconstructive Surgery: Steps towards an International Consensus” published in 2011 in Injury. In addition to developing recommendations, the panel sought to clarify treatment goals that can be achieved using NPWT. It is increasingly recognized that NPWT can be used to achieve a variety of treatment goals, which will vary according to the patient and wound characteristics. Currently, there is a propensity to believe that the only valuable end-point with regards to wound management is complete wound closure. However, the advent of NPWT has introduced the concept that other treatment goals may act as staging posts along the path towards complete closure, which may be useful end-points in any clinical trial. A total of 208 papers that met the inclusion/exclusion criteria were identified through the systematic review. Recommendations were developed according to a modification of the SIGN (Scottish Intercollegiate Guidelines Network) classification system. This classification system is designed to reduce variation in practice and outcome through the development and dissemination of clinical guidelines containing recommendations for effective practice based on current evidence. Areas assessing NPWT use include surgical repair of soft tissue traumatic wounds to provide temporary wound cover, interim use of NPWT to progress a wound from that of a complex wound which may require complex surgical closure (such as a microsurgical free flap) to a smaller and simpler wound which may be adequately managed with a simpler procedure. Also assessed include cases in which wound closure by secondary intention may be a viable option, Gustilo open fractures, burns, skin grafts and flaps. The resulting evidence base is therefore weaker than the wide-spread adoption of NPWT would suggest. In light of this, consensus becomes an important part of recommendation generation. Potential conflicts may include this review was funded by Smith and Nephew. Quality of evidence is low. Strength of recommendation is moderate.
Lau, Tatsioni, Balk, et al., prepared “Usual care in management of chronic wounds: A review of the recent literature” for ARHQ in 2005. This is a systematic review of randomized controlled trials from 1997 to 2004, the authors extracted information about the background care given to control groups to identify treatment modalities that represent the standard of care. A total of 148 RCTs were selected, the largest number of trials were on venous ulcer, followed by diabetic ulcers and pressure ulcers. Just one trial addressed arterial ulcers. The review had some limitations: Inconsistency across studies, large degree of variation in the reporting of basic wound treatment modalities and variation in the duration of usual care. The review does not address outcomes. It has a low risk of bias. Relevant conclusions from the authors were that there is little evidence to indicate which dressings or topical agents are the most effective in the treatment of chronic wounds and that there is evidence that hydrocolloid dressings are more effective than wet to dry dressings in the treatment of pressure sores. In the treatment of venous ulcers non adherent dressings are as effective as hydrocolloid dressings beneath compressive bandages. There is no evidence to support the use of systemic agents for chronic wound healing. Topical agents may be helpful in chronic wound care but further research is required. Compression is more effective than no compression in healing leg venous ulcers. The quality of evidence is high. The strength of recommendation is strong.
The 2013 “International Best Practice Guidelines: Wound Management in Diabetic Foot Ulcers” in Wounds International was compiled by an expert panel of endocrinologists, podiatrists, and rehabilitation specialists. The guideline offers a global wound care plan for practitioners which includes a series of steps for preventing complications through active management combined with appropriate patient education and integrated approach to care. Factors to consider for dressing choice “must begin with a thorough patient and wound assessment” and include location of the wound, extent of the wound (size/depth), amount and type of exudate, the predominant tissue type on the wound surface, condition of the periwound skin, compatibility with other therapies, wound bioburden and risk of infection, avoidance of pain and trauma at dressing changes, quality of life and patient well-being. Regularly reviewing of patient’s wound and dressing is vital. Adjunctive treatments such as NPWT may be considered, if appropriate, where wound not healing. Limitations are that information was collected from Europe and the United Kingdom. The target population was patients with diabetic foot ulcers. Statistics vary and the information appears to be not universally applicable across healthcare systems to Medicare beneficiaries. Also, healthcare providers are not necessarily equally trained and patient access to care varies widely depending on region. The guideline was supported through an educational grant from B Braun (a German medical and pharmaceutical device company). The quality of evidence is low; the strength of recommendation is weak.
A 2014 article in Advances in Wound Care, “A Multicenter Randomized Controlled Trial Comparing Treatment of Venous Leg Ulcers Using Mechanically Versus Electrically Powered Negative Pressure Wound Therapy,” discusses a 13 center non-blinded prospective randomized controlled clinical trial designed to evaluate the relative impact on wound closure using a MP NPWT system (SNaP Wound Care System; Spiracur, Inc., Sunnyvale, CA) versus an EP NPWT system (V.A.C. Therapy System; KCI). The article does not identify the initial population enrolled in the study it just addresses the 40 (n = 19 MP NPWT, n = 21 EP NPWT) patients that completed the study. Each subject was randomly assigned to treatment with either MP NPWT or EP NPWT and evaluated for 16 weeks or complete wound closure. The study had the following weaknesses: small sample, subject and investigator blinding was not performed. There were significant differences in the mean initial wound size between the control and the experimental groups, differences on dressing changes between groups. There was a high risk of performance, detection and publication bias. The study concluded that 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. Potential bias includes this study was sponsored by Spiracur Inc. Also, two authors received research funding from both Spiracur (SNaP device) and other authors consulted for KCI (VAC device). The quality of evidence is low; the strength of recommendation is weak.
O’Donnell TF, Passman MA, Marston WA, et al., had “Management of venous ulcers: Clinical practice guidelines of the Society for Vascular Surgery® and the American Venous Forum” in the Journal of Vascular Surgery in 2014. This is an evidence synthesis, Clinical Practice Guideline developed based on the grading of recommendation assessment, development, and evaluation (GRADE) system. When evidence is lacking, the committee relied on case series supplemented by the best opinion of panel of experts and the recommendation was labeled [BEST PRACTICE]. Such “best practices” from a guideline has obvious advantages but implementation can be a challenge. Focus on “best outcomes for the most reasonable health care dollar” stimulated SVS and AVF to develop and promote a unified set of guidelines for treatment of chronic diseases, such as VLUs. This guideline is presented from the Society for Vascular Surgery and the American Venous Forum. Venous Ulcer Guidelines Committee was divided into six sub-committee sections. The overall committee developed a series of key clinical questions to guide the overall approach for the guideline development; each section team determined the need for a systematic and meta-analysis review which was then agreed on by the entire committee. All guidelines were developed by building on existing guidelines with a complementary literature search by the section sub-committee. It was agreed that the studies reviewed should be published in peer-reviewed journals. The following studies were reviewed: Edinburgh study, a multi-center study of Polish patients, a cross-sectional study in France, the Bonn Vein Longitudinal Study by German Ministry of Health. The sample size of the studies varied widely from 84-40,000 participants. The sample age was unknown or not consistently reported. The guideline is intended for specialists who treat vascular disease and wounds limited to venous leg ulcers. The guideline mentions that future research design should include patient-centered outcomes measures which need to be incorporated into trial design. There is insufficient evidence to generalize to the Medicare population. The quality of evidence is low; the strength of recommendation is weak.
Rhee, Valle, Wilson, et al., with Johns Hopkins Evidence-base Practice Center, prepared a Technology Assessment report, “Negative Pressure Wound Therapy Technologies for Chronic Wound Care in the Home Setting,” for the AHRQ. Johns Hopkins University conducted research to systematically review the efficacy and safety of negative pressure wound therapy (NPWT) for treatment of chronic wounds in the home setting. The focus of this review was use of NPWT in the home population, thus the results are not necessarily applicable to other health care settings in which NPWT may be used. Two independent reviewers screened search results. Studies examined the use of NPWT in patients with chronic wounds, including venous leg ulcers, arterial leg ulcers, diabetic foot ulcers, pressure ulcers, and mixed etiology chronic wounds. Comparative trials were used that followed subjects in the home setting. The group was unable to draw conclusions about the efficacy or safety of NPWT for the treatment of chronic wounds in the home setting due to insufficient evidence. Though NPWT has been used across the wound care spectrum, significant research gaps remain. Standardization of wound care research protocols, such as providing consistency in comparator groups, robust randomized study designs, larger trials, and common definitions of outcomes, would be helpful in providing evidence to inform decisions about the use of NPWT. A very nice summary of the strength of the body of evidence comparing NPWT with other wound care treatments is summarized in Table 5. Pre-defined critical outcomes, those essential for decision making in wound care, were determined to evaluate the strength of evidence. For each of these five critical outcomes, across all wound etiologies, the strength of the evidence is insufficient to draw conclusions on the effectiveness and safety of NPWT compared with other wound care treatments. There were few studies addressing each outcome for each wound etiology; for several outcomes, no studies were identified. Most of the studies were observational studies of poor quality. Only one study was an RCT, and it was judged to be fair quality. The strength of evidence domain of directness was downgraded by the reviewer because some studies used inappropriate control group or used surrogate markers for outcomes. Reviewers were rarely able to evaluate consistency. There were not enough studies to use funnel plots to determine if there was reporting bias. Publication bias may be of concern. Five of the studies reported funding from industry, while Yao et al. did not report funding source. The RCT had a small sample size, and therefore, imprecise results. Some of the observational studies reported limited data on outcomes. Previous systematic reviews on NPWT noted in Table 8 provide a nice summary of systematic reviews on NPWT in various environments. Given the mixture of wound etiologies, and the lack of details about the patients in each of the studies, it was difficult to generalize the results to the overall population. The populations studied all had chronic wounds, and since the chronic wound treatment modalities can be used across the age spectrum, the data we found could be applicable to the Medicare population with moderate generalizability at best. Quality of evidence is low. Strength of recommendation is weak.
Sullivan, Snyder, Tipton, et al., with ECRI Institute published a revised “Negative Pressure Wound Therapy Devices: Technology Assessment Report” in 2009. Over 1400 items were submitted by stakeholders and all were reviewed for relevance. None of the submissions were studies directly comparing different NPWT devices/systems. Submissions included systematic reviews, comparison studies, and uncontrolled case series. In 40 comparison studies, it was found that all of the controlled trials involved the evaluation of one NPWT device, the V.A.C® manufactured by Kinetic Concepts Inc. (KCI). None of the 40 comparison studies met the design and conduct requirements to be considered high quality, only seven studies could be considered moderate quality, and the majority of studies (82%) were rated low quality. AHRQ noted conclusions made in the TA agreed with the systematic reviews examined; the reviews indicated the majority of evidence on NPWT was of poor quality. The TA indicates the most commonly reported adverse events associated with NPWT are pain, bleeding, and infection. Of the 37 studies reporting events, seven (19%) studies described NPWT as a safe treatment. Fewer complications were reported in the NPWT-treated patients than in those receiving other wound therapies in 19 (51%) studies and similar complications were reported in 8 (22%) studies. The TA noted important study features were not typically reported such as concealment of allocation, reporting of randomization methods and use of power analysis to ensure adequate study size, blinding patients and especially wound assessors, and reporting of complete wound healing data to insure the internal validity of study results. No study included in the TA reported that the physicians were blinded to treatment assignment, and only 12% of the studies reported blinding of outcome assessors. In only 7% of studies was there concealment of allocation to treatment, one of the most crucial elements of any randomized controlled trial with failure typically resulting in selection bias. The TA noted the findings could not be transferred from one wound type to another so numerous high quality studies of several different wound types would be necessary in order to determine if any one NPWT system or component provides a significant therapeutic distinction over another. The TA stated the strongest evidence of efficacy will come from properly designed and conducted RCTs that can be replicated by independent research units. The quality of evidence is low; the strength of recommendation is weak.
In 2013, the Journal of American Medical Association (JAMA) Dermatology published “Frequency of Debridements and Time to Heal; A Retrospective Cohort Study of 312,744 Wounds” by Wilcox, Carter and Covington. The stated desired objective in this article was to investigate healing outcomes and debridement frequency in a large wound data set. This is a retrospective cohort study. Data was collected from 525 wound care centers from June 1, 2008, through June 31, 2012, using a web-based clinical management system. A referred sample of 154,644 patients with 312,744 wounds of all causes (of an initial data set of 364,534 wounds) participated. A total of 47.1% were male. Median age was 69 years (age range, 19-112 years), with 59.2% having one wound. Eligibility criteria included age older than 18 years, receiving at least 1 debridement, and having been discharged from the system. Advanced therapeutic treatment was ineligible. Because of incomplete, questionable, or ineligible data, 57,190 wounds were not included. Most wounds were diabetic foot ulcers (19.0%), venous leg ulcers (26.1%), and pressure ulcers (16.2%). Debridement (removal of necrotic tissue and foreign bodies from the wound) occurred at different frequencies. Wound healing was defined as complete epithelialization with dimensions at 0×0×0cm. A total of 70.8% of wounds healed. The median number of debridements was 2 (range, 1-138). Frequent debridement healed more wounds in a shorter time (P less than .001). In regression analysis, significant variables included male sex, physician category, wound type, increased patient age, and increased wound age, area, and depth. The odds ratio varied considerably for each variable. The authors concluded the more frequent the debridements, the better the healing, (in spite of noting that the median number of debridements required is two). Although limited by retrospective data, this study’s strength was the analysis of the largest wound data set to date. Potential bias is a conflict of interest as the review was obtained from and conducted by a for-profit wound care company and some authors are employed by a for-profit wound care company. Limitations of the study include the use of retrospective data and the statistical analysis. Further analysis will be necessary to determine the precise effect size due to debridement frequency because certain causes will have unique factors come into play. They conclude that the issue remains that there has not yet been an adequately powered retrospective trial to test the efficacy of debridement of wounds. Quality of evidence is low. Strength of recommendation is weak.
The 2008 “Principles of best practice: Vacuum assisted closure: recommendations for use. A Consensus Document” is World Union of Wound Healing Societies’ Initiative. This is a consensus expert opinion drawn from selected clinical evidence (RCTs, Retrospective match group analysis, Randomized Controlled Crossover Studies, Randomized Controlled Pilot Studies, Retrospective Controlled Studies and Data Compilation from publish literature). It has an unclear risk of bias. VAC therapy must be used as part of an individualized, comprehensive treatment plan and is indicated for both acute and chronic wounds. VAC therapy can be considered for deep complex wounds, for post-surgery wounds and, occasionally, for superficial wounds in addition to standard treatments. For patients with ischemic wounds, referral to a vascular surgeon should be considered prior to VAC therapy. Under ideal conditions (especially in the absence of infection), well perfused wounds will respond quickly (i.e., within one week) with evidence of granulation tissue formation. This can be used to test vascularity and suitability of VAC therapy. VAC therapy can be used in a number of ways to manage the complex diabetic foot wound, post-surgery diabetic foot wounds and superficial diabetic foot wounds. It is recognized that compression therapy is regarded as the first-line treatment for venous leg ulcers. However, there is a role for VAC therapy in inflammatory or complex therapy-resistant leg ulcers that are unsuitable for compression. The use of portable VAC systems may also allow ambulatory patients to be treated at home and can reduce the need for hospitalization. In patients with inflammatory ulcers, VAC therapy can be used to enhance wound bed preparation before definitive surgical closure or delayed secondary healing. VAC therapy is recommended as a first-line treatment for grade/stage 3 and 4 pressure ulcers in certain situations and should be used as part of a comprehensive treatment plan. VAC therapy should be considered as a first-line treatment for dehisced sternal wounds following cardiac surgery. This can be used as a bridge to definitive surgical closure or to achieve delayed primary closure or flap reconstruction and closure. The guideline also recommends VAC therapy is in the treatment of: open abdominal wounds, in the treatment of complex traumatic wounds. Finally it states that further research is needed to increase understanding of the therapeutic effects of VAC therapy to give clinicians stronger arguments to support its use. In particular, future trials should focus on the generation of level 1 evidence and further comparative data for specific indications. This will help to clarify the potential for VAC therapy in different wound types and to enhance clinical decision making in various population groups. The quality of evidence is low; the strength of recommendation is moderate.