Cost-effectiveness of negative pressure wound therapy in patients with many comorbidities and severe wounds of various etiology.

This study analyzed a cross-section of patients with severe chronic wounds and multiple comorbidities at an outpatient wound clinic, with regard to the cost-effectiveness and cost-benefit of negative pressure wound therapy (intervention) vs. no negative pressure wound therapy (control) at 1 and 2 years. Medicare reimbursement charges for wound care were used to calculate costs. Amputation charges were assessed using diagnosis-related groups. Cost-benefit analysis was based on ulcer-free months and cost-effectiveness on quality-adjusted life-years. Undiscounted costs, benefits, quality-adjusted life-years, undiscounted and discounted incremental net health benefits, and incremental cost-effectiveness ratios were calculated for unmatched and matched cohorts. There were 150 subjects in the intervention group and 154 controls before matching and 103 subjects in each of the matched cohorts. Time to heal for the intervention cohort was significantly shorter compared to the controls (270 vs. 635 days, p = 1.0 × 10-7 , matched cohorts). The intervention cohort had higher benefits and quality-adjusted life-year gains compared to the control cohort at years 1 and 2; by year 2, the gains were 68-73% higher. In the unmatched cohorts, the incremental net health benefit was $9,933 per ulcer-free month at year 2 for the intervention; the incremental cost-effectiveness ratio was -825,271 per quality-adjusted life-year gained (undiscounted costs and benefits). For the matched cohorts, the incremental net health benefits was only $1,371 per ulcer-free month for the intervention, but the incremental cost-effectiveness ratio was $366,683 per quality-adjusted life-year gained for year 2 (discounted costs and benefits). In a patient population with severe chronic wounds and serious comorbidities, negative pressure wound therapy resulted in faster healing wounds and was more cost-effective with greater cost-benefits than not using negative pressure wound therapy. Regarding overall cost-effectiveness, the intervention was still expensive, but that is the reality amidst limited treatment options for such serious cases of chronic wounds.

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.

A pilot study evaluating non-contact low-frequency ultrasound and underlying molecular mechanism on diabetic foot ulcers.

Non-contact low-frequency ultrasound (NCLF-US) devices have been increasingly used for the treatment of chronic non-healing wounds. The appropriate dose for NCLF-US is still in debate. The aims of this pilot study were to evaluate the relationship between dose and duration of treatment for subjects with non-healing diabetic foot ulcers (DFUs) and to explore the correlation between wound healing and change of cytokine/proteinase/growth factor profile. This was a prospective randomised clinical study designed to evaluate subjects with non-healing DFUs for 5 weeks receiving standard of care and/or NCLF-US treatment. Subjects were randomly assigned to one of the three groups: application of NCLF-US thrice per week (Group 1), NCLF-US once per week (Group 2) and the control (Group 3) that received no NCLF-US. All subjects received standard wound care plus offloading for a total of 4 weeks. Percent area reduction (PAR) of each wound compared with baseline was evaluated weekly. Profiles of cytokines/proteinase/growth factors in wound fluid and biopsied tissue were quantified to explore the correlation between wound healing and cytokines/growth factor expression. Twelve DFU patients, 2 (16·7%) type 1 and 10 (83·3%) type 2 diabetics, with an average age of 58 ± 10 years and a total of 12 foot ulcers were enrolled. Average ulcer duration was 36·44 ± 24·78 weeks and the average ABI was 0·91 ± 0·06. Group 1 showed significant wound area reduction at weeks 3, 4 and 5 compared with baseline, with the greatest PAR, 86% (P < 0·05); Groups 2 and 3 showed 25% PAR and 39% PAR, respectively, but there were no statistically significant differences between Groups 2 and 3 over time. Biochemical and histological analyses indicated a trend towards reduction of pro-inflammatory cytokines (IL-6, IL-8, IL-1ß, TNF-α and GM-CSF), matrix metalloproteinase-9 (MMP-9), vascular endothelial growth factor (VEGF) and macrophages in response to NCLF-US consistent with wound reduction, when compared with control group subjects. This proof-of-concept pilot study demonstrates that NCLF-US is effective in treating neuropathic diabetic foot ulcers through, at least in part, inhibiting pro-inflammatory cytokines in chronic wound and improving tissue regeneration. Therapeutic application of NFLU, thrice (3) per week, renders the best wound area reduction.

Ease of use, safety, and efficacy of integra bilayer wound matrix in the treatment of diabetic foot ulcers in an outpatient clinical setting: a prospective pilot study.

BACKGROUND: Integra bilayer wound matrix (IBWM) is a bilayer skin replacement system composed of a dermal regeneration layer and a temporary epidermal layer. It is used to treat various types of deep, large wounds via an inpatient procedure in an operating room. We sought to determine ease of use and effectiveness of IBWM in an outpatient clinical setting when treating diabetic foot ulcers. In addition, no epidermal autografting was performed in conjunction with the IBWM after silicone release, as is common in the inpatient setting. METHODS: This 12-week, single-arm, prospective pilot study was conducted in three outpatient clinics. Weekly evaluations included monitoring the wound for signs of infection during the 12-week follow-up phase. RESULTS: Eleven patients with diabetic foot ulcers who met the inclusion and exclusion criteria were enrolled. One patient was discontinued from the study owing to noncompliance leading to a serious adverse event. Therefore, ten patients who received the study intervention were included in the per-protocol population reported herein. The mean patient age was 60.6 years, with an average 11-year history of diabetes mellitus. Each ulcer was located on the plantar aspect of the foot. No infection was reported during the study. Patients treated with IBWM showed progressive wound healing over time: the greatest mean wound reduction was approximately 95% in week 12. Seven of ten patients (70%) achieved complete wound closure by week 12. No recurrent ulcers were reported during follow-up. CONCLUSIONS: These results are consistent with the hypothesis that IBWM is easy to use, safe, and effective when used on diabetic foot ulcers in an outpatient clinical setting without the secondary procedure of autografting for closure.

The impact of a podiatric lead limb preservation team on disease outcomes and risk prediction in the diabetic lower extremity: a retrospective cohort study.

BACKGROUND: We used a model of lower-extremity ulceration to determine the impact of a podiatric lead limb preservation team on identified relationships among risk factors, predictors of ulceration, amputation, and clinical outcomes of lower-extremity disease in patients with diabetes mellitus. METHODS: A total of 485 patients with diabetes mellitus were randomly selected from the diabetic population and included in this retrospective cohort study. Patients were then stratified into two groups: those who received specialty podiatric medical care and those who did not. Data covering a 5-year period were collected using electronic medical records and chart abstraction to capture detailed treatment characteristics, ulcer status, and surgical outcomes. RESULTS: Overall, the frequencies of inpatient and outpatient encounters and the durations of hospital stays were significantly greater with increasing wound depth and in the presence of infection. In addition, the overall ulcer incidence was greater in patients with callus (34.3% versus 10.3%, P < .0001) with and without neuropathy (20.4% and 4.1%, P < .0001). Among patients treated in a specialty multidiscipline podiatric medical setting, the proportion of all amputations that were "minor" was significantly increased (33.7% versus 67.3%, P = .0006), and survival was significantly improved (19.5% versus 7.7%, P < .0001). CONCLUSIONS: Early identification of individuals at increased risk for lower-extremity ulceration and subsequent referral for advanced multidiscipline podiatric medical specialty care may decrease rates of ulceration and proximal amputation and improve survival in patients with diabetes mellitus who are at high risk for ulceration and limb loss.