Negative Pressure Wound Therapy Patients Research Articles

Single use Negative Pressure Wound Therapy (NPWT) system in the management of knee arthroplasty

BackgroundWound complication, skin blister formation in particular, causes devastating consequences after total knee arthroplasty (TKA). Negative Pressure Wound Therapy (NPWT) tries to improve wound management leading to decrease length of hospital stay and better clinical outcomes. Low body mass index (BMI) could play a part in wound recovery management although lacking evidence. This study compared length of hospital stay and clinical outcomes between NPWT and Conventional groups, and factors affected and how BMI affected.MethodsThis was a retrospective clinical record review of 255 (160 NPWT and 95 Conventional) patients between 2018 and 2022. Patient demographics including body mass index (BMI), surgical details (unilateral or bilateral), length of hospital stay, clinical outcomes including skin blisters occurrence, and major wound complications were investigated.ResultsMean age of patients at surgery was 69.95 (66.3% were female). Patients treated with NPWT stayed significantly longer in the hospital after joint replacement (5.18 days vs. 4.55 days; p = 0.01). Significantly fewer patients treated with NPWT found to have blisters (No blisters: 95.0% vs. 87.4%; p = 0.05). In patients with BMI < 30, percentage of patients requiring dressing change was significantly lower when treated with NPWT than conventional (0.8% vs. 33.3%).ConclusionPercentage of blisters occurrence in patients who underwent joint replacement surgery is significantly lower using NPWT. Patients using NPWT stayed significantly longer in the hospital after surgery because significant proportion received bilateral surgery. NPWT patients with BMI < 30 were significantly less likely to change wound dressing.

Comparison of the Efficiency of Epidermal Growth Factor and Negative Pressure Wound Therapy in Diabetic Foot Patients.

Advanced modalities are used for wounds where conventional treatment is insufficient in diabetic foot patients. In this study, we investigated the effects of using Epidermal growth factor (EGF) and NPWTmodalities alone or in combination on the frequency and level of amputation. In the retrospective study, which included 286 patients in total, 76 patients were referred with the decision of amputation or amputation was planned during hospitalization. After the treatments, amputation and distalization of amputation were found 73.3% and 33.3% in the conventional treatment patients. While 86.4% amp and 18.2% amp distalization were found in negative pressure wound therapy (NPWT) only patients, this rate was 52.4% and 90.5% in EGF + NPWT patients, 50% and 83.3% in EGF only patients. While amp and distalization rates were found to be significantly better in those receiving only EGF or EGF + NPWT (P = .015, P = .017 respectively for amputation and P = .000 for distalization), no difference was found in those receiving EGF and EGF + NPWT. As a result of our study, although npwt contributed positively to the number and level of amputations compared to conventional treatment, a significant improvement was found in the number and level of amps when EGF was used alone or combined with NPWT. With this result, EGF was thought to be an important treatment modality that should be evaluated in diabetic foot ulcers (DFUs) without amputation decision.

Case control study investigating the clinical utility of NPWT in the perineal region following abdominoperineal resection for rectal adenocarcinoma: a single center study

BackgroundPerineal wound complications are common after abdominoperineal resection (APR) for rectal adenocarcinoma. Delayed wound healing may postpone postoperative adjuvant therapy and, therefore, lead to a worse survival rate. Negative-pressure wound therapy (NPWT) has been suggested to improve healing, but research on this subject is limited.MethodsThe aim of this study was to assess whether NPWT reduces surgical site infections (SSI) after APR for rectal adenocarcinoma when the closure is performed with a biological mesh and a local flap. A total of 21 consecutive patients had an NPWT device (Avelle, Convatec™) applied to the perineal wound. The study patients were compared to a historical cohort in a case–control setting in relation to age, body mass index, tumor stage, and length of neoadjuvant radiotherapy. The primary outcome was the surgical site infection rate. The secondary outcomes were the wound complication rate, the severity of wound complications measured by the Clavien–Dindo classification, length of hospital stay, and surgical revision rate.ResultsThe SSI rate was 33% (7/21) in the NPWT group and 48% (10/21) in the control group, p = 0.55. The overall wound complication rate was 62% (13/21) in NPWT patients and 67% (14/21) in the control group, p > 0.90. The length of hospital stay was 15 days in the NPWT group and 13 in the control group, p = 0.34. The wound severity according to the Clavien–Dindo classification was 3b in 29% (6/21) of the NPWT group and in 38% (8/21) of the control group. A surgical revision had to be performed in 29% (6/21) of the cases in the NPWT group and 38% (8/21) in the control group, p = 0.73.ConclusionNPWT did not statistically decrease surgical site infections or reduce wound complication severity in perineal wounds after APR in this case–control study. The results may be explained by technical difficulties in applying NPWT in the perineum, especially in female patients. NPWT devices should be further developed to suit the perineal anatomy before their full effect can be assessed.Trial registration The study was registered as a prospective registry study (266/2018, registered 15th of November 2018)

Negative Pressure Wound Therapy in Facilitating Wound Healing After Surgical Decompression for Metastatic Spine Disease

The risk of wound-related complications, including surgical site infections (SSIs), in patients undergoing surgery for metastatic spine disease (MSD) is high. Consequently, patients requiring wound revision surgery face delay in resuming oncological care and incur additional hospitalization. Recent reports suggest that negative pressure wound therapy (NPWT) applied on a closed wound at the time of surgery significantly reduces postoperative wound complications in degenerative spine disease and trauma setting. Here, we report a single institution experience with incisional NPWT in patients undergoing surgery for MSD. We compared rates of wound complications requiring surgical revision in a surgical cohort of patients with or without NPWT from 2015 to 2020. Adult patients with radiographic evidence of MSD with mechanical instability and/or accelerated neurological decline were included in the study. NPWT was applied on a closed wound in the operating room and continued for 5 days or until discharge, whichever occurred first. A total of 42 patients were included: 28 with NPWT and 14 without. Patient demographics including underlying comorbidities were largely similar. NPWT patients had higher rates of prior radiation to the surgical site (36% vs. 0%, P= 0.017) and longer fusion constructs (6.7 vs. 3.9 levels, P < 0.001). Three patients (21%) from the control group and none from the NPWT group contracted SSI requiring wound washout (P= 0.032). Our data suggest that SSI and wound dehiscence are significantly reduced with the addition of incisional NPWT in this vulnerable population.

PIT1 Negative Pressure Wound Therapy for Pressure Ulcer: Effect on Outcomes and Utilization Using Real-World DATA

Clinical trials evaluating negative pressure wound therapy (NPWT) as a treatment for pressure ulcer (PU) have been inconclusive. The objective of this research was to evaluate the effect of NPWT on length of stay (LOS), charges, and mortality for PU patients. Clinical data collected over a 4-year period from a large medical institution in the OMNY Health System Database were used to identify adult PU patients. Patients were excluded if also diagnosed with diabetic, chronic skin non-pressure, or varicose ulcers. Current Procedural Terminology codes were used to divide patients into NPWT and comparison cohorts. Crude estimates for mortality (percent and 95% confidence interval [95% CI]) and for LOS and charges (median, quartiles 1 and 3 [Q1, Q3]) were generated for each outcome. Propensity score methods were used to account for underlying differences between cohorts. After exclusions, 749 patients were divided into NPWT (N=135) and comparison (N=614) cohorts. Crude mortality was slightly greater in the NPWT cohort (28.9%; 95% CI: 21.2%-36.5%) than in the comparison cohort (22.2%; 95% CI: 18.9%-25.4%). NPWT patients incurred notably higher charges (median [Q1-Q3]: $65,197 [$32,232-$143,607] vs. $13,850 [$3,056-$35,929]) and LOS (median [Q1-Q3]: 11 days [7, 22] vs. 5 days [3, 9]) than comparison patients. After application of propensity score methods, the adjusted mortality relative risk was 1.20 (95% CI: 0.88-1.65), and the adjusted median differences in LOS and charges were 5.8 days (Q1-Q3: 3.9-9.2) and $30,900 (Q1-Q3: $15,434-$58,868), respectively. No notable positive effects of NPWT on PU outcomes or hospitalizations were observed even after adjusting for underlying differences. Residual confounding by indication could be a possible explanation for the observed associations between NPWT and PU outcomes. Further research is needed to examine longer term differences in outcomes such as readmission rates and to evaluate drivers of cost difference.

ALGINATE versus traitement par pression négative : comparaison de l’efficacité, de la tolérance et des coûts de prise en charge de patients après exérèse chirurgicale. Étude clinique multicentrique, randomisée de non-infériorité sur 113 patients

Pure calcium alginate dressing (ALGINATE) and Negative Pressure Wound Therapy (NPWT) are frequently used for the preparation of skin excisions for a split thickness skin graft take. The trial compared the healing efficacy, safety and cost of patient care for these two treatments. This randomized, non-inferiority trial enrolled 113patients who underwent skin excision (>30cm2) and received ALGINATE or NPWT. The primary outcome was the time to obtain optimal granulation tissue for a split thickness skin graft take. Secondary outcomes were the occurrence of adverse events (AEs) and the impact of the patient care cost on the Social Security budget. The mean time to optimal granulation was similar between ALGINATE and NPWT: approximately 20days. No AE was reported with ALGINATE while 24% of patients treated with NPWT presented an AE. Following hospitalization, 94% of ALGINATE patients were cared for at home by a private nurse, while 90% of NPWT patients were followed up in aftercare and rehabilitation facilities or home hospitalization. Therefore, the cost of treatment per patient for the French Social Security was 498€ with ALGINATE and 2104€ with NPWT. This trial has demonstrated that ALGINATE has a similar healing efficacy to that of NPWT, and that it is markedly better with regard to patient safety and cost savings. ALGINATE should therefore be preferred to NPWT in this indication.

OUTCOMES OF VAC VERSUS CONVENTIONAL DRESSING IN MANAGEMENT OF DIABETIC FOOT ULCER

Background: Foot wounds in people with diabetes mellitus (DM) are 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. Objective: To assess the efficacy of vacuum assisted closure dressings as compared to conventional moist wound dressings in improving the healing process in diabetic foot wounds. Patients and methods: This prospective randomized comparative study was conducted in the General and Vascular Surgery Departments at Al-Azhar university hospitals and Al-Ahrar teaching hospital, in the period from January 2019 to May 2020. The study included 30 patients randomized into two equal groups: VAC therapy and conventional dressing suffering from diabetic foot wounds. All chronic wounds where conventional dressings indicated were included in the study. Results: Wound bed showed signs of healing by granulation tissue formation in 11 among 15 patients (73.3%) in VAC therapy group. In conventional treatment, 4 showed granulation among 15 patients (26.7%) one week after initiation of treatment. (P=0.01). There was a statistically significant difference between average granulation as % of ulcer area and it was significantly high in vacuum dressing. It was 50.2 ± 18.9 in Conventional treatment compared with 77.4 ± 19.3 in NPWT group (p- value = 0.005). Also, at the end of the study, we found that the total mean cost in conventional dressing group was 1993 ± 193 EP compared to 2261 ± 183 EP in VAC group. There was a difference in the total cost finally. Being higher in cost, VAC therapy although has a shorter hospital stay and faster healing time in comparison with conventional dressing. Conclusion: Negative pressure wound therapy (NPWT) using vacuum-assisted closure (VAC) was more efficacious than conventional therapy in the management of foot ulcers in diabetic patients. Hospital stay was significantly shorter in NPWT patients, so less consuming of hospital service than conventional dressing. This is finally decreasing the total budget to the hospital.

Open abdomen closure methods for severe abdominal sepsis: a retrospective cohort study.

The open abdomen (OA) procedure as part of damage control surgery represents a significant surgical advance in severe intra-abdominal infections. Major techniques used for OA are negative pressure wound therapy (NPWT) and non-NPWT. The aim of this retrospective study is to evaluate the effects of different abdominal closure methods and their outcomes in patients presenting with abdominal sepsis treated with OA. We retrospectively analyzed clinical outcomes of patients affected by severe intra-abdominal sepsis treated with OA. Demographic features, mortality prediction score, abdominal closure methods, length of hospital stay, complications and mortality rates of patients were determined and compared. This study included 106 patients, of whom 77 underwent OA with NPWT and 29 with non-NPWT. OA duration was longer in NPWT patients (p = 0.007). In-hospital mortality rates in NPWT and in non-NPWT patients were 40.3% and 51.7%, respectively (p = 0.126), with an overall 30-day mortality rate of 18.2% and 51.7%, respectively (p = 0.0002). After emergency colorectal surgery, patients who underwent OA with NPWT had a lower rate of colostomy (p = 0.025). NPWT is the best temporary abdominal closure technique to decrease mortality and colostomy rates in patients managed with OA for severe intra-abdominal infections.

Effects of Negative Pressure Wound Therapy on Wound Dehiscence and Surgical Site Infection Following Instrumented Spinal Fusion Surgery—A Single Surgeon's Experience

Incisional negative pressure wound therapy (NPWT) is used in many surgical specialties to prevent postoperative dehiscence and surgical site infections (SSIs). However, little is known about the role of incisional NPWT in spine fusion surgery. Therefore, we sought to report a single surgeon's experience using incisional NPWT and describe its effects on dehiscence and SSIs after instrumented spine surgery. We compared rates of hospital readmission and return to the operating room for dehiscence and SSIs in a consecutive series of patients who underwent spinal fusion surgery with or without NPWT from 2015 to2018. A total of 393 patients without and 76 patients with NPWT were included for analysis. Half way through the data collection period, all patients who underwent anterior lumbar fusion received NPWT. Three of 15 (20.0%) of non-NPWT patients who underwent anterior lumbar fusion had dehiscence or SSI compared with zero of 23 (0.0%) of NPWT patients (P= 0.01). NPWT for posterior surgeries was used on a case-by-case basis using risk factors that contribute to SSIs and dehiscence. NPWT patients had higher rates of spinal neoplasia (0.5% vs. 11.3%, P < 0.0001), osteomyelitis/diskitis (1.3% vs. 7.5%, P= 0.02), durotomy (14.9% vs. 28.6%, P= 0.007), revision surgery (32.2% vs. 59.6%, P= 0.0001), and longer fusion constructs (7 vs. 11 levels, P < 0.0001) but had similar rates of dehiscence and SSIs as non-NPWT patients (5.6% vs. 5.7%, P= 0.98). NPWT decreases dehiscence and SSIs in patients undergoing lumbar fusion through an anterior approach. When preferentially used in patients at high risk for postoperative wound complications, NPWT prevents increased rates of dehiscence and SSI.

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

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

La terapia a pressione negativa presso i reparti acuti dell’Ospedale Regionale di Mendrisio: risultati di un audit clinico/Negative pressure wound therapy in the acute care units of the Mendrisio Regional Hospital: results of a clinical audit

Negli ultimi vent’anni si sono diffuse e perfezionate nella pratica clinica specifiche tecnologie per il trattamento delle ferite di difficile guarigione, come la terapia a pressione negativa (negative pressure wound therapy, NPWT). Tale terapia consente l’accelerazione dei tempi di guarigione di ferite inveterate e una sicura riduzione dei tempi di degenza nei pazienti ricoverati. All’interno di un reparto clinico per acuti risulta tuttavia indispensabile definire le corrette indicazioni ed il modello organizzativo che consenta di ottimizzare le risorse, ridurre gli sprechi e dare risposte tempestive ed efficaci alle persone che possono beneficiare di questo trattamento. È stata condotta un’analisi quantitativa sull’uso della metodica NPWT nei reparti acuti dell’Ospedale Beata Vergine di Mendrisio nell’anno 2017, base per la realizzazione di un audit clinico; i dati ottenuti sono stati rapportati alle attuali evidenze scientifiche sul tema per evidenziare allineamenti e/o scostamenti nella pratica clinica quotidiana. L’audit è uno strumento di Governo Clinico; utilizzare questa metodologia vuol dire favorire una migliore conoscenza da parte degli operatori sanitari delle attività cliniche e gestionali. È, infatti, un processo di revisione strutturata fra pari che ha come obiettivo quello di individuare le opportunità di miglioramento al fine di introdurle nella pratica professionale quotidiana. Gli assistiti che necessitano di medicazione NPWT hanno solitamente un grado di complessità medio-alta, richiedono quindi un assessment preciso ed approfondito, oltre ad una presa a carico multiprofessionale. Gli staff infermieristici necessitano di formazione specifica, consulenza medica e/o infermieristica esperta, adeguato supporto documentale ed informatico al fine di assicurare sicurezza, qualità e razionalità delle cure, outcome positivi di salute. Molti sono gli articoli scientifici e le esperienze a favore di una presa a carico infermieristica di pazienti con medicazioni complesse gestite tramite dispositivi NPWT. I presupposti affinché questo possa avvenire in sicurezza prevedono un processo definito in modo chiaro e condiviso fra professionisti sanitari ed assistiti, formazione aggiornata, documentazione corretta.&#x0D; During last twenty years, tailored technologies were spread and improved; they are aimed to support the treatment of difficult-toheal wounds, such as negative pressure wound therapy (NPWT). This type of treatment lead to promote healing process and to reduce hospital stay of patients. In an acute care setting, planning and managing these new technologies represent a key-point. We did a retrospective study about NPWT in acute care setting in Beata Vergine Regional Hospital in 2017, aimed at performing a clinical audit; the results were compared to scientific literature to detect differences in daily clinical practice. Audit is a very helpful tool for Clinical Government: this method leads to improve the management of clinical activities because the entire staff (physicians and nurses) obtains important data about care setting. Patients treated by NPWT are usually difficult to treat and need a correct assessment and a multidisciplinary approach. Consequently, fundamental aspects are represented by nursing staff education and its relationship with medical staff, data collections and computer-assisted technologies development. Significant scientific literature and clinical experience seem to recommend a nursing management of NPWT patients. This aspect is very interesting and it can be improved by specific education, adequate organization and correct data collection.

Negative Pressure Wound Therapy for Closed Surgical Wounds in Musculoskeletal Oncology Patients - A Case-Control Trial

Following excision of musculoskeletal tumours, patients are at high risk of wound issues such as infection, dehiscence and delayed healing. This is due to a multitude of factors including the invasive nature of the disease, extensive soft tissue dissection, disruption to blood and lymphatic drainage, residual cavity and adjuvant therapies. The use of negative pressure wound therapy (NPWT) has a growing body of evidence on its beneficial effect of wound healing such as promoting cell differentiation, minimising oedema and thermoregulation. Traditionally, these dressings have been used for open or dehisced wounds; however recent research has investigated its role in closed wounds.Aim:To evaluate the effect of NPWT in patients with closed wounds, either primarily or with flap coverage, in our high risk group. Consecutive patients who had a NPWT dressing applied were selected, and a control group was established by a blinded researcher with matching for tissue diagnosis, surgical site, gender and age. The primary outcome measured was documented for wound complications, with secondary data collected on radiotherapy and wound drainage.Results:Patients were well matched between the intervention (n=9) and control (n=9) groups for gender, age and tissue diagnosis. Both groups had 1 patient who underwent preoperative radiotherapy. A total of 3 wound infections occurred in the control group and none in the NPWT group. Overall there was a trend towards lower drain output and statistically significantly reduced infection rate in the NPWT group.Conclusion:In this short series, despite the NPWT patients having more additional risk factors for wound issues, they resulted in fewer infections. The sample size is not sufficient to have statistically significant reduction. Further evaluation on the value of NPWT in this patient group should be prospectively evaluated.

Wound Penetration of Cefazolin, Ciprofloxacin, Piperacillin, Tazobactam, and Vancomycin During Negative Pressure Wound Therapy.

Objective: Negative pressure wound therapy (NPWT) uses subatmospheric pressure as a noninvasive adjunct to treat wounds and has demonstrated clinical efficacy by accelerating healing of a variety of acute and chronic wounds. NPWT may also play a role in preventing or treating wound infections, possibly by increasing wound penetration of antibiotics. However, clinical data in patients undergoing antibiotic and NPWT treatment are limited. Approach: To evaluate the wound penetration of antibiotics in NPWT patients, we conducted a prospective, observational study of burn and trauma patients treated with NPWT and systemic antibiotics. We evaluated the plasma pharmacokinetic profile of systemic vancomycin, ciprofloxacin, cefazolin, and piperacillin/tazobactam, as well as total and unbound antibiotic concentrations in wound exudate from the same patients. Results: Data from 32 patients with 37 wounds undergoing NPWT demonstrated that vancomycin, ciprofloxacin, and piperacillin/tazobactam all penetrated wounds with exudate to plasma concentration ratios more than 0.8. Cefazolin did not penetrate wounds in patients undergoing NPWT as effectively, with an average exudate to plasma concentration ratio of 0.51. Innovation: Clinical data on the wound penetration of antibiotics in patients undergoing NPWT are limited, but these data suggest that antibiotics have different capacities for wound penetration during NPWT that should be considered when making clinical decisions. Conclusion: This initial report suggests that (1) vancomycin, ciprofloxacin, and piperacillin/tazobactam effectively penetrate wounds during NPWT and (2) cefazolin as well as other antibiotics may not penetrate wounds during NPWT.

Safety and efficacy of prophylactic negative pressure wound therapy following open saphenous vein harvest in cardiac surgery: a feasibility study

Surgical site complications following great saphenous vein (GSV) harvest presents a significant risk of morbidity. Negative pressure wound therapy (NPWT) has shown promise in the treatment and prophylaxis of open wounds and surgical incisions but has not been studied following GSV harvest. We performed a feasibility study examining the use of NPWT following GSV harvest for coronary bypass surgery. Sixty-four patients were recruited in this single-centre, single-blind, randomized controlled trial. The primary endpoint assessed feasibility by examining rates of device complication and malfunction. Secondary endpoints included rates of surgical site infection, lower leg complications, discharge date, and quality of life at discharge and 6 weeks. NPWT was delivered using the Prevena NPWT device. There were no complications associated with NPWT which required intervention aside from discontinuation. NPWT was tolerated in 91% (30/33) of patients for the duration of treatment with an average of 4.8 days (±1.45 days). Device malfunction which required discontinuation was 6% (2/33) and involved a malfunctioning pressure sensor and did not affect patient care or present safety concerns. One patient had allergic contact dermatitis to the adhesive and had the device removed. NPWT patients had an earlier date of discharge (6 vs 10 days, P = 0.008), increased ability for self-care ( P = 0.0234) and quality of life ( P = 0.039) at initial assessment, and increased mobility at initial and follow-up assessment ( P = 0.0117 and 0.0123). The use of NPWT following GSV harvest is safe, well tolerated and improves postoperative recovery with prolonged impact on mobility at 6 weeks. https://clinicaltrials.gov/ct2/show/NCT01698372 ; registration number: NCT01698372.

Can Drainage Using a Negative-Pressure Wound Therapy Device Replace Traditional Sample Collection Methods?

In 2015 a new device for the collection of mediastinal fluid from patients with deep sternal wound infection (DSWI) in the presence of negative-pressure wound therapy (NPWT) became available. The present study was designed to evaluate whether changing sample collection devices increased micro-organism detection in patients undergoing NPWT. During 2013-2014, 207 samples were collected and cultured from NPWT patients (n = 23) to demonstrate the presence of DSWI using reticulated polyurethane sponge culture, a swab, and blood culture. In 2015, a new collection device was introduced for specimen collection. A total of 357 samples (n = 17) were collected using the ESwab(™) (Copan, Murrieta, CA) for deep and superficial wound sample collection. In addition, blood culture devices were used for collecting mediastinal fluid aspirated directly from the wound and biologic fluid obtained from the NPWT device. Fisher exact test was performed to test the rate of independence rate of micro-organism identification using the NPWT sponge device and taking blood culture results as a reference for micro-organism identification. After the introduction of the new collection device in our hospital, an overall increase in the detection of micro-organisms (46.7%) was reported. During 2013-2014 our traditional microbiologic collection method did not detect a pathogen in 30.4% of patients. During 2015, the new sample collection approach, direct from the NPWT device, improved micro-organism detection by 10.4% and reduced DSWIs with undetected pathogens to 17.6% (p < 0.01). As a result of proficiency gained in the last year, the most representative specimen in wound infection was represented by mediastinal fluid collected directly from the wound and the NPWT device. Given the correlation between the blood culture of micro-organisms detected using the ESwab device from the wound, mediastinal drainage, and drainage from the NPWT device, we can assume that the NPWT device may replace the other biologic sampling devices.

Use of Negative-Pressure Wound Dressings to Prevent Surgical Site Complications After Primary Hip Arthroplasty: A Pilot RCT.

Negative-pressure wound therapy (NPWT) is increasingly used for primary surgical incisions despite the paucity of evidence. Study objectives were to assess the use of NPWT on surgical sites to prevent infections and other wound complications after elective primary hip arthroplasty and to consider feasibility of a larger trial. A nonmasked, randomized controlled pilot trial. Patients were recruited preoperatively from the preadmission clinic of an Australian hospital during 2013-2014. Computer-generated randomization was performed with allocation concealed until completion of surgery. The intervention group received NPWT (PICO) while the control group received the standard care hydrocolloid, reinforced with 2 absorbent dressings. Patients were followed for 6 weeks for postoperative complications (infection, length of stay, readmission) and skin complications (bruising, seroma, hematoma, dehiscence). Feasibility end points included numbers recruited, randomized, and followed up; fidelity; and costs. Of 77 people approached, 76 were recruited, and 70 were randomized. Of 35 in the negative-pressure group, 2 received the standard dressing. Attrition at 6 weeks exceeded 10% in both groups. Dressing costs were lower in the control group ($3.01/d vs $38.40/d); SSI incidence was 2/35 in the NPWT and 3/35 in the control group (intention to treat: risk ratio [RR] = 0.67; 95% confidence interval [CI] = 0.12-3.7; P = .65). NPWT patients experienced more postoperative wound complications (RR = 1.6; 95% CI = 1.0-2.5; P = .04). A reduction of 3% in SSI incidence suggests that a definitive trial requires approximately 900 patients per group. Yet there is uncertainty around the benefit of NPWT after elective hip arthroplasty.

Effectiveness and Safety of Negative-Pressure Wound Therapy for Diabetic Foot Ulcers

The authors conducted a meta-analysis to evaluate the effectiveness and safety of negative-pressure wound therapy for diabetic foot ulcers. PubMed, EMBASE, and the Cochrane Library were searched to identify relevant studies published up to February of 2013. All randomized controlled trials comparing negative-pressure wound therapy and non-negative-pressure wound therapy (i.e., standard wound care) for diabetic foot ulcers were included. Results were pooled using meta-analysis to assess the efficacy and safety of negative pressure in managing diabetic foot ulcers. The databases were derived from eight qualified studies that included a total of 669 patients. Overall, compared with the non-negative-pressure wound therapy-treated diabetic foot ulcers, negative pressure resulted in a significantly higher proportion of healed ulcers (relative risk, 1.52; 95 percent CI, 1.23 to 1.89; p<0.001), more reduction of ulcer area (standardized mean difference, 0.89; 95 percent CI, 0.41 to 1.37; p=0.003), and shorter time to wound healing (standardized mean difference, -1.10; 95 percent CI, -1.83 to -0.37; p=0.003). Negative-pressure wound therapy patients also experienced significantly fewer major amputations (relative risk, 0.14; 95 percent CI, 0.04 to 0.51; p=0.003), but the rate of minor amputations was not affected (p=0.837). No significant difference was observed between negative-pressure wound therapy and non-negative-pressure wound therapy (p=0.683). No heterogeneity among studies was detected. Negative-pressure wound therapy appears to be more effective for diabetic foot ulcers compared with non-negative-pressure wound therapy, and has a similar safety profile. Therapeutic, II.

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

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

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

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

Gene expression profiling of negative-pressure-treated skin graft donor site wounds

Negative-pressure wound therapy (NPWT) is widely used to improve skin wound healing. Although NPWT has been studied as a treatment for wound closure and healing, the molecular mechanisms explaining its therapeutic effects remain unclear. To investigate the effect of NPWT on gene expression, and to discover the genes most dominantly responding to this treatment during skin wound healing, we applied negative pressure on split-thickness skin graft donor sites from the first postoperative day (POD) to the seventh POD. Biopsies were collected from 4 NPWT-treated and 2 control patients. Two biopsy samples were taken from each patient: one from intact skin before graft harvesting, and one on the seventh POD from the donor site wound. Genome-wide microarrays were performed on all samples. Gene expression changes on the seventh POD were compared between NPWT and control patients, and were analyzed for statistical significance. In addition, we analyzed wound exudates for volume, and for concentrations of leukocytes, erythrocytes, and haemoglobin. NPWT induced major changes in gene expression during healing. These changes ranged from 10-fold induction to 27-fold suppression. The genes most induced were associated with cell proliferation and inflammation, and the most down-regulated genes were linked to epidermal differentiation. Our results provide the first insight into the molecular mechanisms behind NPWT, and suggest that NPWT enhances specific inflammatory gene expression at the acute phase associated with epithelial migration and wound healing. However, its continued use may inhibit epithelial differentiation.