Precision in Prevention: Tailoring Single-Use Negative Pressure Wound Therapy Utilization Through Artificial Intelligence-Based Surgical Site Complications Risk and Cost Modeling.

Background: Surgical site complications (SSCs) are common, yet preventable hospital-acquired conditions. Single-use negative pressure wound therapy (sNPWT) has been shown to be effective in reducing rates of these complications. In the era of value-based care, strategic allocation of sNPWT is needed to optimize both clinical and financial outcomes. Materials and Methods: We conducted a retrospective analysis using data from the Premier Healthcare Database (2017-2021) for 10 representative open procedures in orthopedic, abdominal, cardiovascular, cesarean delivery, and breast surgery. After separating data into training and validation sets, various machine learning algorithms were used to develop pre-operative SSC risk prediction models. Model performance was assessed using standard metrics and predictors of SSCs were identified through feature importance evaluation. Highest-performing models were used to simulate the cost-effectiveness of sNPWT at both the patient and population level. Results: The prediction models demonstrated good performance, with an average area under the curve of 76%. Prominent predictors across subspecialities included age, obesity, and the level of procedure urgency. Prediction models enabled a simulation analysis to assess the population-level cost-effectiveness of sNPWT, incorporating patient and surgery-specific factors, along with the established efficacy of sNPWT for each surgical procedure. The simulation models uncovered significant variability in sNPWT's cost-effectiveness across different procedural categories. Conclusions: This study demonstrates that machine learning models can effectively predict a patient's risk of SSC and guide strategic utilization of sNPWT. This data-driven approach allows for optimization of clinical and financial outcomes by strategically allocating sNPWT based on personalized risk assessments.

Economic Analysis of AbClo, a Novel Abdominal Fascia Closure Device, for Patients With an Open Abdomen Following Trauma or Acute Abdominal Surgery.

BACKGROUND: Open Abdomen (OA) cases represent a significant surgical and resource challenge. AbClo is a novel non-invasive abdominal fascial closure device that engages lateral components of the abdominal wall muscles to support gradual approximation of the fascia and reduce the fascial gap. The study objective was to assess the economic implications of AbClo compared to negative pressure wound therapy (NPWT) alone on OA management. METHODS: We conducted a cost-minimization analysis using a decision tree comparing the use of the AbClo device to NPWT alone among patients with midline laparotomy for trauma or acute abdominal surgery who were ineligible for primary fascial closure. The time horizon was limited to the length of the inpatient hospital stay, and costs were considered from the perspective of the US Medicare payer. Clinical effectiveness data for AbClo was obtained from a randomized clinical trial. Cost data was obtained from the published literature. Probabilistic and deterministic sensitivity analyses were performed. The primary outcome was incremental cost. RESULTS: The mean cumulative costs per patient were $76 582 for those treated with NPWT alone and $70,582 for those in the group treated with the AbClo device. Compared to NPWT alone, AbClo was associated with lower incremental costs of -$6012 (95% CI -$19 449 to +$1996). The probability that AbClo was cost-savings compared to NPWT alone was 94%. CONCLUSIONS: The use of AbClo is an economically attractive strategy for management of OA in in patients with midline laparotomy for trauma or acute abdominal surgery who were ineligible for primary fascial closure.

Patient-reported outcome and cost implication of acute salvage of infected implant-based breast reconstruction with negative pressure wound therapy with Instillation (NPWTi) compared to standard care.

INTRODUCTION: Implant loss due to infection is the most devastating complication of implant-based breast reconstruction. The use of negative pressure wound therapy with instillation(NPWTi) for salvage of infected implant-based breast reconstructions has shown promising results allowing early reinsertion of a new implant as an alternative to the current management with delayed reinsertion. This study compares the patient-reported outcome and cost implication of NPWTi to the current management. METHODS: Twenty cases of infected breast implants treated with NPWTi(V.A.C. VERAFLO™ Therapy), followed by early reinsertion of new implants were compared to 20 cases that had delayed reinsertion(non-NPWTi). Patient satisfaction was evaluated using the BREAST-Q questionnaire. The average cost per patient was calculated using total operative expense, cost of inpatient stay, investigations, antibiotics, and outpatient visits. RESULTS: Treatment with NPWTi allowed earlier reinsertion of a new implant (NPWTi: 10.3 ± 2.77days vs. non-NPWTi: 247.45±111.28days, p<0.001). Patients in the NPWTi group reported higher satisfaction. The average cost per patient for NPWTi and non-NPWTi was £14,343.13±£2,786.70 and £8,920.31±£3,005.73, respectively(p<0.001). All patients treated with NPWTi had one admission and spent 11.9 ± 4.1days as inpatients, while non-NPWTi patients had 2.1 ± 0.3 admissions(p<0.001) and spent 7.1 ± 5.8days(p<0.004) as inpatients. Patients treated with NPWTi had more procedures (NPWTi:3.35±0.81 Vs. non-NPWTi:2.2 ± 0.41, p = 0.006); however, three non-NPWTi cases required flap reconstruction. CONCLUSION: Patients treated with NPWTi reported higher satisfaction, received a new and earlier implant, and had fewer admissions and outpatient visits; however, they incurred higher average costs, longer inpatient stays, and underwent more procedures. Early implant reinsertion preserves skin envelope; hence avoiding additional cost and stress related to further major autologous reconstruction.

Single-use negative pressure wound therapy reduces costs in closed surgical incisions: UK and US economic evaluation.

OBJECTIVE: Single-use negative pressure wound therapy (sNPWT) following closed surgical incisions has a demonstrable effect in reducing surgical site complications (SSC). However, there is little health economic evidence to support its widespread use. We sought to evaluate the cost-effectiveness of sNPWT compared with standard care in reducing SSCs following closed surgical incisions. METHOD: A decision analytic model was developed to explore the total costs and health outcomes associated with the use of the interventions in patients following vascular, colorectal, cardiothoracic, orthopaedic, C-section and breast surgery from the UK National Health Service (NHS) and US payer perspective over a 12-week time horizon. We modelled complications avoided (surgical site infection (SSI) and dehiscence) using data from a recently published meta-analysis. Cost data were sourced from published literature, NHS reference costs and Centers for Medicare and Medicaid Services. We conducted subgroup analysis of patients with diabetes, an American Society of Anesthesiologists (ASA) score ≥3 and body mass index (BMI) ≥30kg/m2. A sensitivity analysis was also conducted. RESULTS: sNPWT resulted in better clinical outcomes and overall savings of £105 per patient from the UK perspective and $637 per patient from the US perspective. There were more savings when higher-risk patients with diabetes, or a BMI ≥30kg/m2 or an ASA≥3 were considered. We conducted both one-way and probabilistic sensitivity analysis, and the results suggested that this conclusion is robust. CONCLUSION: Our findings suggest that the use of sNPWT following closed surgical incisions saves cost when compared with standard care because of reduced incidence of SSC. Patients at higher risk should be targeted first as they benefit more from sNPWT. This analysis is underpinned by strong and robust clinical evidence from both randomised and observational studies.

Cost-effectiveness of single-use negative-pressure therapy compared with standard care for prevention of reconstruction failure in prepectoral breast reconstruction.

BACKGROUND: Single-use negative-pressure wound therapy (sNPWT) has been reported to reduce the incidence of reconstruction failure in prepectoral breast reconstruction compared with standard surgical dressings. The aim of this economic evaluation was to investigate the cost-effectiveness of sNPWT compared with standard care for the prevention of reconstruction failure in prepectoral breast reconstruction in the UK. METHOD: A decision tree model was used to estimate the expected cost and effectiveness per patient. Effectiveness was measured both by the number of reconstruction failures avoided and the gain in quality-adjusted life-years (QALYs). The baseline incidence of reconstruction failure (8.6 per cent) was taken from a recently published study of 2655 mastectomies in the UK. The effectiveness of sNPWT used results from a clinical study comparing sNPWT with standard dressings. Previously published utility weights were applied. The cost of reconstruction failure was estimated from detailed resource data from patients with reconstruction failure, applying National Health Service reference costs. One-way, probabilistic, scenario and threshold analyses were conducted. RESULTS: The undiscounted cost per patient associated with reconstruction failure was estimated to be £23 628 (£22 431 discounted). The use of sNPWT was associated with an expected cost saving of £1706 per patient, an expected increase in QALYs of 0.0187 and an expected 0.0834 reconstruction failures avoided. Cost-effectiveness acceptability analysis demonstrated that, at a threshold of £20 000 per QALY, 99.94 per cent of the simulations showed sNPWT to be more cost-effective than standard care. CONCLUSION: Among patients undergoing immediate prepectoral breast reconstruction, the use of sNPWT is more cost-effective than standard dressings.

Negative pressure wound therapy: device design, indications, and the evidence supporting its use.

Introduction: Negative pressure wound therapy (NPWT) has become a mainstay in the armamentarium for wound care. Since the initial commercial vacuum-assisted closure device became available in 1995, subsequent research has confirmed the positive physiological effects of negative pressure on wound healing. Traditionally, NPWT has been used to improve healing of open nonsurgical wounds by secondary intention. However, the clinical applications of NPWT have significantly broadened, and now also include use in open surgical wounds, closed surgical incisions, and skin graft surgery. In addition, devices have evolved and now include functionality and features such as instillation, antimicrobial sponges, and portability.Areas covered: This article reviews the history, background, and physiology underlying NPWT, as well as the most commonly used devices. In addition, an evidence-based discussion of the current clinical applications of NPWT is presented, with a focus on those with high levels of evidence.Expert opinion: Future directions for device development include modifications to increase ease of use by patients and to allow its use in a broader array of anatomic areas. Lastly, more research with high levels of evidence is needed to better define the outcomes associated with NPWT, including in relation to specific clinical applications and cost.

Cost-effectiveness analysis of negative pressure wound therapy dressings after open inguinal vascular surgery - The randomised INVIPS-Trial.

AIM: While the scientific evidence in favour of negative pressure wound therapy (NPWT) dressings on sutured incisions in the prevention of surgical site infections (SSIs) has increased, the cost-effectiveness after vascular surgery has not been evaluated. The aim of this study was to evaluate the cost-effectiveness of NPWT compared to standard dressings for the prevention of SSIs after open inguinal vascular surgery. MATERIALS AND METHODS: Patient data were retrieved from the randomised INVIPS-trial's open arm, which included patients randomised to either NPWT or standard dressings. The patients were surveyed for SSIs for 90 days postoperatively. The patients' individual cost data were included and analysed from a healthcare perspective. The patients' quality of life was measured using the Vascuqol-6 questionnaire pre- and 30 days postoperatively. Cost-effectiveness of NPWT was determined by decreased or equal total costs and a significant reduction in SSI incidence. RESULTS: The mean vascular procedure-related costs at 90 days were €16,621 for patients treated with NPWT (n = 59) and €16,285 for patients treated with standard dressings (n = 60), p = 0.85. The SSI incidence in patients treated with NPWT was 11.9% (n = 7/59) compared to 30.0% (n = 18/60) with standard dressings, p = 0.015. This corresponds to an increased mean cost of €1,853 per SSI avoided. The cost-effectiveness plane of incremental vascular procedure-related costs and difference in Vascuqol-6 score showed that 42% of estimates were in the quadrant where NPWT was dominant. CONCLUSION: NPWT is considered cost-effective over standard dressings in patients undergoing open inguinal vascular surgery due to reduced SSI incidence at no higher costs.

Experience with use of improvised negative pressure wound therapy in the management of wounds with exposed bone.

Wounds with exposed bone pose a significant challenge in healing. Negative pressure wound therapy has simplified reconstructive options. In economically constrained regions, this has been modified with materials that are affordable. Its effect on such wounds has not been well studied and so case summaries of 15 patients with 17 wounds who were managed with modified negative pressure wound therapy at Ntasiobi Specialist Hospital and ESUT Teaching Hospital between 2015 and 2019 were obtained. The procedure progressed satisfactorily in 88% of patients with granulation tissue covering the bones while the procedure was discontinued in 12%. The modified negative pressure wound therapy achieves similar results as the patented version and is recommended where resources are limited.

Clinical and Health-Care Cost Analysis of Negative Pressure Dressing in Primary and RevisionTotal Knee Arthroplasty: A Systematic Review and Meta-Analysis.

BACKGROUND: Negative pressure wound therapy (NPWT) has been used because of its perceived advantages in reducing surgical site infections, wound complications, and the need for further surgery. The purpose of this study was to assess the infection rates, wound complications, length of stay, and financial burden associated with NPWT use in primary and revision total knee arthroplasty (TKA). METHODS: We performed a PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) systematic review of the existing literature on using NPWT in primary and revision TKA. PubMed, Embase, Science Direct, and the Cochrane Library were utilized. The risk of bias was evaluated using the ROBINS-I (Risk Of Bias In Non-randomised Studies - of Interventions) tool, and the quality of evidence was evaluated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria. RESULTS: Twelve articles that evaluated 1,403 primary TKAs and 279 revision TKAs were reviewed. NPWT significantly reduced complication rates in revision TKA. However, there was no significant difference in infection rates between NPWT and regular dressings in primary or revision TKA. NPWT use in primary TKA significantly increased the risk of blistering, although no increase in reoperations was noted. The analysis showed a possible reduction in length of stay associated with NPWT use for both primary and revision TKA, with overall health-care cost savings. CONCLUSIONS: Based on a meta-analysis of the existing literature, we do not recommend the routine use of NPWT. However, in high-risk revision TKA and selected primary TKA cases, NPWT reduced wound complications and may have health-care cost savings. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Cost-utility analysis of standard dressing compared with incisional negative-pressure wound therapy among patients with closed surgical wounds following major trauma to the lower limb.

AIMS: To compare the cost-utility of standard dressing with incisional negative-pressure wound therapy (iNPWT) in adults with closed surgical wounds associated with major trauma to the lower limbs. METHODS: A within-trial economic evaluation was conducted from the UK NHS and personal social services (PSS) perspective based on data collected from the Wound Healing in Surgery for Trauma (WHiST) multicentre randomized clinical trial. Health resource utilization was collected over a six-month post-randomization period using trial case report forms and participant-completed questionnaires. Cost-utility was reported in terms of incremental cost per quality-adjusted life year (QALY) gained. Sensitivity analysis was conducted to test the robustness of cost-effectiveness estimates while uncertainty was handled using confidence ellipses and cost-effectiveness acceptability curves. RESULTS: The incremental cost of standard dressing versus iNPWT over six months was £2,037 (95% confidence interval (CI) £349 to £3,724). There was an insignificant increment in QALYs gained in the iNPWT group (0.005, 95% CI -0.018 to 0.028). The probability of iNPWT being cost-effective at £20,000 per QALY was 1.9%. The results remained robust in the sensitivity analysis. CONCLUSION: The within-trial economic evaluation suggests that iNPWT is unlikely to be a cost-effective alternative to standard dressing in adults with closed surgical wounds to their lower limbs. Cite this article: Bone Joint J 2020;102-B(8):1072-1081.

Negative-pressure wound therapy compared with standard dressings following surgical treatment of major trauma to the lower limb: the WHiST RCT.

BACKGROUND: Major trauma is the leading cause of death in people aged < 45 years. Patients with major trauma usually have lower-limb fractures. Surgery to fix the fractures is complicated and the risk of infection may be as high as 27%. The type of dressing applied after surgery could potentially reduce the risk of infection. OBJECTIVES: To assess the deep surgical site infection rate, disability, quality of life, patient assessment of the surgical scar and resource use in patients with surgical incisions associated with fractures following major trauma to the lower limbs treated with incisional negative-pressure wound therapy versus standard dressings. DESIGN: A pragmatic, multicentre, randomised controlled trial. SETTING: Twenty-four specialist trauma hospitals representing the UK Major Trauma Network. PARTICIPANTS: A total of 1548 adult patients were randomised from September 2016 to April 2018. Exclusion criteria included presentation > 72 hours after injury and inability to complete questionnaires. INTERVENTIONS: Incisional negative-pressure wound therapy (n = 785), in which a non-adherent absorbent dressing covered with a semipermeable membrane is connected to a pump to create a partial vacuum over the wound, versus standard dressings not involving negative pressure (n = 763). Trial participants and the treating surgeon could not be blinded to treatment allocation. MAIN OUTCOME MEASURES: Deep surgical site infection at 30 days was the primary outcome measure. Secondary outcomes were deep infection at 90 days, the results of the Disability Rating Index, health-related quality of life, the results of the Patient and Observer Scar Assessment Scale and resource use collected at 3 and 6 months post surgery. RESULTS: A total of 98% of participants provided primary outcome data. There was no evidence of a difference in the rate of deep surgical site infection at 30 days. The infection rate was 6.7% (50/749) in the standard dressing group and 5.8% (45/770) in the incisional negative-pressure wound therapy group (intention-to-treat odds ratio 0.87; 95% confidence interval 0.57 to 1.33; p = 0.52). There was no difference in the deep surgical site infection rate at 90 days: 13.2% in the standard dressing group and 11.4% in the incisional negative-pressure wound therapy group (odds ratio 0.84, 95% confidence interval 0.59 to 1.19; p = 0.32). There was no difference between the two groups in disability, quality of life or scar appearance at 3 or 6 months. Incisional negative-pressure wound therapy did not reduce the cost of treatment and was associated with a low probability of cost-effectiveness. LIMITATIONS: Owing to the emergency nature of the surgery, we anticipated that some patients who were randomised would subsequently be unable or unwilling to participate. However, the majority of the patients (85%) agreed to participate. Therefore, participants were representative of the population with lower-limb fractures associated with major trauma. CONCLUSIONS: The findings of this study do not support the use of negative-pressure wound therapy in patients having surgery for major trauma to the lower limbs. FUTURE WORK: Our work suggests that the use of incisional negative-pressure wound therapy dressings in other at-risk surgical wounds requires further investigation. Future research may also investigate different approaches to reduce postoperative infections, for example the use of topical antibiotic preparations in surgical wounds and the role of orthopaedic implants with antimicrobial coatings when fixing the associated fracture. TRIAL REGISTRATION: Current Controlled Trials ISRCTN12702354 and UK Clinical Research Network Portfolio ID20416. FUNDING: This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 38. See the NIHR Journals Library for further project information.

WHAT DID THE TRIAL FIND?: We found no evidence of a difference in the rate of surgical site infection between those patients randomised to negative-pressure wound therapy and those patients randomised to standard wound dressings. There was no difference in the rate of other wound healing complications or in the patients' self-report of disability, health-related quality of life or scar healing. Negative-pressure wound therapy is very unlikely to be cost-effective for the NHS. In conclusion, and contrary to previous reports, the findings of this study do not support the use of negative-pressure wound therapy in patients having surgery for major trauma to their legs.

Major trauma is the leading cause of death worldwide in people aged < 45 years and a significant cause of short- and long-term health problems. In 85% of major trauma patients, the injury involves broken bones. Surgery to fix broken bones in the lower limbs is complicated and has risks, one of the main ones being wound infection. In these patients, rates of wound infection have been reported to be as high as 27%. One factor that may affect the risk of infection is the type of dressing applied after surgery. In this trial, we compared standard wound dressings with a new treatment called incisional negative-pressure wound therapy. Negative-pressure wound therapy is a special type of dressing whereby gentle suction is applied to the surface of the wound. A total of 1548 patients from 24 specialist trauma hospitals in the UK agreed to take part and were assigned at random to receive either a standard wound dressing or negative-pressure wound therapy after their surgery. We reviewed the recovery of the patients for 6 months. We recorded how many had an infection in the surgical wound and asked the patients to rate the extent of their disability, their quality of life and the scar healing. We also collected information about the cost of treatment.

Negative pressure wound therapy for surgical wounds healing by primary closure.

BACKGROUND: Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). Existing evidence for the effectiveness of NPWT on postoperative wounds healing by primary closure remains uncertain. OBJECTIVES: To assess the effects of NPWT for preventing SSI in wounds healing through primary closure, and to assess the cost-effectiveness of NPWT in wounds healing through primary closure. SEARCH METHODS: In June 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries and references of included studies, systematic reviews and health technology reports. There were no restrictions on language, publication date or study setting. SELECTION CRITERIA: We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another type of NPWT. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, assessment using the Cochrane 'Risk of bias' tool, and quality assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: In this third update, we added 15 new randomised controlled trials (RCTs) and three new economic studies, resulting in a total of 44 RCTs (7447 included participants) and five economic studies. Studies evaluated NPWT in the context of a wide range of surgeries including orthopaedic, obstetric, vascular and general procedures. Economic studies assessed NPWT in orthopaedic, obstetric and general surgical settings. All studies compared NPWT with standard dressings. Most studies had unclear or high risk of bias for at least one key domain. Primary outcomes Four studies (2107 participants) reported mortality. There is low-certainty evidence (downgraded twice for imprecision) showing no clear difference in the risk of death after surgery for people treated with NPWT (2.3%) compared with standard dressings (2.7%) (risk ratio (RR) 0.86; 95% confidence interval (CI) 0.50 to 1.47; I2 = 0%). Thirty-nine studies reported SSI; 31 of these (6204 participants), were included in meta-analysis. There is moderate-certainty evidence (downgraded once for risk of bias) that NPWT probably results in fewer SSI (8.8% of participants) than treatment with standard dressings (13.0% of participants) after surgery; RR 0.66 (95% CI 0.55 to 0.80 ; I2 = 23%). Eighteen studies reported dehiscence; 14 of these (3809 participants) were included in meta-analysis. There is low-certainty evidence (downgraded once for risk of bias and once for imprecision) showing no clear difference in the risk of dehiscence after surgery for NPWT (5.3% of participants) compared with standard dressings (6.2% of participants) (RR 0.88, 95% CI 0.69 to 1.13; I2 = 0%). Secondary outcomes There is low-certainty evidence showing no clear difference between NPWT and standard treatment for the outcomes of reoperation and incidence of seroma. For reoperation, the RR was 1.04 (95% CI 0.78 to 1.41; I2 = 13%; 12 trials; 3523 participants); for seroma, the RR was 0.72 (95% CI 0.50 to 1.05; I2 = 0%; seven trials; 729 participants). The effect of NPWT on occurrence of haematoma or skin blisters is uncertain (very low-certainty evidence); for haematoma, the RR was 0.67 (95% CI 0.28 to 1.59; I2 = 0%; nine trials; 1202 participants) and for blisters the RR was 2.64 (95% CI 0.65 to 10.68; I2 = 69%; seven trials; 796 participants). The overall effect of NPWT on pain is uncertain (very low-certainty evidence from seven trials (2218 participants) which reported disparate measures of pain); but moderate-certainty evidence suggests there is probably little difference between the groups in pain after three or six months following surgery for lower limb fracture (one trial, 1549 participants). There is also moderate-certainty evidence for women undergoing caesarean sections (one trial, 876 participants) and people having surgery for lower limb fractures (one trial, 1549 participants) that there is probably little difference in quality of life scores at 30 days or 3 or 6 months, respectively. Cost-effectiveness Five economic studies, based wholly or partially on trials included in our review, assessed the cost-effectiveness of NPWT compared with standard care. They considered NPWT in four indications: caesarean sections in obese women; surgery for lower limb fracture; knee/hip arthroplasty and coronary artery bypass graft surgery. They calculated quality-adjusted life-years for treatment groups and produced estimates of the treatments' relative cost-effectiveness. The reporting quality was good but the grade of the evidence varied from moderate to very low. There is moderate-certainty evidence that NPWT in surgery for lower limb fracture was not cost-effective at any threshold of willingness-to-pay and that NPWT is probably cost-effective in obese women undergoing caesarean section. Other studies found low or very low-certainty evidence indicating that NPWT may be cost-effective for the indications assessed. AUTHORS' CONCLUSIONS: People experiencing primary wound closure of their surgical wound and treated prophylactically with NPWT following surgery probably experience fewer SSI than people treated with standard dressings (moderate-certainty evidence). There is no clear difference in number of deaths or wound dehiscence between people treated with NPWT and standard dressings (low-certainty evidence). There are also no clear differences in secondary outcomes where all evidence was low or very low-certainty. In caesarean section in obese women and surgery for lower limb fracture, there is probably little difference in quality of life scores (moderate-certainty evidence). Most evidence on pain is very low-certainty, but there is probably no difference in pain between NPWT and standard dressings after surgery for lower limb fracture (moderate-certainty evidence). Assessments of cost-effectiveness of NPWT produced differing results in different indications. There is a large number of ongoing studies, the results of which may change the findings of this review. Decisions about use of NPWT should take into account surgical indication and setting and consider evidence for all outcomes.

Negative pressure wound therapy for surgical wounds healing by primary closure.

BACKGROUND: Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). Existing evidence for the effectiveness of NPWT on postoperative wounds healing by primary closure remains uncertain. OBJECTIVES: To assess the effects of NPWT for preventing SSI in wounds healing through primary closure, and to assess the cost-effectiveness of NPWT in wounds healing through primary closure. SEARCH METHODS: In June 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries and references of included studies, systematic reviews and health technology reports. There were no restrictions on language, publication date or study setting. SELECTION CRITERIA: We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another type of NPWT. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, assessment using the Cochrane 'Risk of bias' tool, and quality assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: In this third update, we added 15 new randomised controlled trials (RCTs) and three new economic studies, resulting in a total of 44 RCTs (7447 included participants) and five economic studies. Studies evaluated NPWT in the context of a wide range of surgeries including orthopaedic, obstetric, vascular and general procedures. Economic studies assessed NPWT in orthopaedic, obstetric and general surgical settings. All studies compared NPWT with standard dressings. Most studies had unclear or high risk of bias for at least one key domain. Primary outcomes Four studies (2107 participants) reported mortality. There is low-certainty evidence (downgraded twice for imprecision) showing no clear difference in the risk of death after surgery for people treated with NPWT (2.3%) compared with standard dressings (2.7%) (risk ratio (RR) 0.86; 95% confidence interval (CI) 0.50 to 1.47; I2 = 0%). Thirty-nine studies reported SSI; 31 of these (6204 participants), were included in meta-analysis. There is moderate-certainty evidence (downgraded once for risk of bias) that NPWT probably results in fewer SSI (8.8% of participants) than treatment with standard dressings (13.0% of participants) after surgery; RR 0.66 (95% CI 0.55 to 0.80 ; I2 = 23%). Eighteen studies reported dehiscence; 14 of these (3809 participants) were included in meta-analysis. There is low-certainty evidence (downgraded once for risk of bias and once for imprecision) showing no clear difference in the risk of dehiscence after surgery for NPWT (5.3% of participants) compared with standard dressings (6.2% of participants) (RR 0.88, 95% CI 0.69 to 1.13; I2 = 0%). Secondary outcomes There is low-certainty evidence showing no clear difference between NPWT and standard treatment for the outcomes of reoperation and incidence of seroma. For reoperation, the RR was 1.04 (95% CI 0.78 to 1.41; I2 = 13%; 12 trials; 3523 participants); for seroma, the RR was 0.72 (95% CI 0.50 to 1.05; I2 = 0%; seven trials; 729 participants). The effect of NPWT on occurrence of haematoma or skin blisters is uncertain (very low-certainty evidence); for haematoma, the RR was 0.67 (95% CI 0.28 to 1.59; I2 = 0%; nine trials; 1202 participants) and for blisters the RR was 2.64 (95% CI 0.65 to 10.68; I2 = 69%; seven trials; 796 participants). The overall effect of NPWT on pain is uncertain (very low-certainty evidence from seven trials (2218 participants) which reported disparate measures of pain); but moderate-certainty evidence suggests there is probably little difference between the groups in pain after three or six months following surgery for lower limb fracture (one trial, 1549 participants). There is also moderate-certainty evidence for women undergoing caesarean sections (one trial, 876 participants) and people having surgery for lower limb fractures (one trial, 1549 participants) that there is probably little difference in quality of life scores at 30 days or 3 or 6 months, respectively. Cost-effectiveness Five economic studies, based wholly or partially on trials included in our review, assessed the cost-effectiveness of NPWT compared with standard care. They considered NPWT in four indications: caesarean sections in obese women; surgery for lower limb fracture; knee/hip arthroplasty and coronary artery bypass graft surgery. They calculated quality-adjusted life-years for treatment groups and produced estimates of the treatments' relative cost-effectiveness. The reporting quality was good but the grade of the evidence varied from moderate to very low. There is moderate-certainty evidence that NPWT in surgery for lower limb fracture was not cost-effective at any threshold of willingness-to-pay and that NPWT is probably cost-effective in obese women undergoing caesarean section. Other studies found low or very low-certainty evidence indicating that NPWT may be cost-effective for the indications assessed. AUTHORS' CONCLUSIONS: People experiencing primary wound closure of their surgical wound and treated prophylactically with NPWT following surgery probably experience fewer SSI than people treated with standard dressings (moderate-certainty evidence). There is no clear difference in number of deaths or wound dehiscence between people treated with NPWT and standard dressings (low-certainty evidence). There are also no clear differences in secondary outcomes where all evidence was low or very low-certainty. In caesarean section in obese women and surgery for lower limb fracture, there is probably little difference in quality of life scores (moderate-certainty evidence). Most evidence on pain is very low-certainty, but there is probably no difference in pain between NPWT and standard dressings after surgery for lower limb fracture (moderate-certainty evidence). Assessments of cost-effectiveness of NPWT produced differing results in different indications. There is a large number of ongoing studies, the results of which may change the findings of this review. Decisions about use of NPWT should take into account surgical indication and setting and consider evidence for all outcomes.

Nurses' and surgeons' views and experiences of surgical wounds healing by secondary intention: A qualitative study.

AIMS AND OBJECTIVES: To explore surgeons' and nurses' perspectives of managing surgical wounds healing by secondary intention. BACKGROUND: Every year, more than 10 million surgical operations are performed in the NHS in the UK. Most surgical wounds heal by primary intention, where the edges of the wound are brought together with staples, sutures, adhesive glue or clips. Sometimes wounds are deliberately left open to heal, from the base up, known as "healing by secondary intention." These wounds are often slow to heal, prone to infection and complex to manage. DESIGN: A qualitative, descriptive approach, using semi-structured interviews. METHODS: Interviews with five (general, vascular and plastic) surgeons and 7 nurses (3 tissue viability nurses, 2 district and 1 community nurse, and 1 hospital nurse) working in hospital and community care settings in two locations in the north of England. Data analysis followed the recommended sequential steps of "Framework" approach. Consolidated criteria for reporting qualitative research guided the study report. RESULTS: Participants reported that the main types of wounds healing by secondary intention that they manage are extensive abdominal cavity wounds; open wounds relating to treatment for pilonidal sinus; large open wounds on the feet of patients with diabetes; and axilla and groin wounds, associated with removal of lymph nodes for cancer. Infection and prolonged time to healing were the main challenges. Negative pressure wound therapy was the most favoured treatment option. CONCLUSIONS: Negative pressure wound therapy was advocated by professionals despite a lack of research evidence indicating clinical or cost-effectiveness. Our findings underscore the need for rigorous evaluation of negative pressure wound therapy, and other wound care treatments, through studies that include economic evaluation. RELEVANCE FOR CLINICAL PRACTICE: Clinical decision-making in wound care could be optimised through further robust studies to inform practitioners about the cost-effectiveness of available treatments.

Deep Learning-Based Risk Model for Best Management of Closed Groin Incisions After Vascular Surgery.

BACKGROUND: Reduced surgical site infection (SSI) rates have been reported with use of closed incision negative pressure therapy (ciNPT) in high-risk patients. METHODS: A deep learning-based, risk-based prediction model was developed from a large national database of 72,435 patients who received infrainguinal vascular surgeries involving upper thigh/groin incisions. Patient demographics, histories, laboratory values, and other variables were inputs to the multilayered, adaptive model. The model was then retrospectively applied to a prospectively tracked single hospital data set of 370 similar patients undergoing vascular surgery, with ciNPT or control dressings applied over the closed incision at the surgeon's discretion. Objective predictive risk scores were generated for each patient and used to categorize patients as "high" or "low" predicted risk for SSI. RESULTS: Actual institutional cohort SSI rates were 10/148 (6.8%) and 28/134 (20.9%) for high-risk ciNPT versus control, respectively (P < 0.001), and 3/31 (9.7%) and 5/57 (8.8%) for low-risk ciNPT versus control, respectively (P = 0.99). Application of the model to the institutional cohort suggested that 205/370 (55.4%) patients were matched with their appropriate intervention over closed surgical incision (high risk with ciNPT or low risk with control), and 165/370 (44.6%) were inappropriately matched. With the model applied to the cohort, the predicted SSI rate with perfect utilization would be 27/370 (7.3%), versus 12.4% actual rate, with estimated cost savings of $231-$458 per patient. CONCLUSIONS: Compared with a subjective practice strategy, an objective risk-based strategy using prediction software may be associated with superior results in optimizing SSI rates and costs after vascular surgery.

Protocol for a parallel economic evaluation of a trial comparing two surgical strategies in severe complicated intra-abdominal sepsis: the COOL-cost study.

BACKGROUND: The risk of death in severe complicated intra-abdominal sepsis (SCIAS) remains high despite decades of surgical and antimicrobial research. New management strategies are required to improve outcomes. The Closed Or Open after Laparotomy (COOL) trial investigates an open-abdomen (OA) approach with active negative pressure peritoneal therapy. This therapy is hypothesized to better manage peritoneal bacterial contamination, drain inflammatory ascites, and reduce the risk of intra-abdominal hypertension leading to improved survival and decreased complications. The total costs and cost-effectiveness of this therapy (as compared with standard fascial closure) are unknown. METHODS: We propose a parallel cost-utility analysis of this intervention to be conducted alongside the 1-year trial, extrapolating beyond that using decision analysis. Using resource use metrics (e.g., length of stay, re-admissions) from patients at all study sites and microcosting data from patients enrolled in Calgary, Alberta, the mean cost difference between treatment arms will be established from a publicly-funded health care payer perspective. Quality of life will be measured at 6 months and 1 year postoperatively with the Euroqol EQ-5D-5 L and SF-36 surveys. A within-trial analysis will establish cost and utility at 1 year, using a bootstrapping approach to provide confidence intervals around an estimated incremental cost-effectiveness ratio. If neither operative strategy is economically dominant, Markov modeling will be used to extrapolate the cost per quality-adjusted life years gained to 2-, 5-, 10-year, and lifetime horizons. Future costs and benefits will be discounted at 1.5% per annum. A cost-effectiveness acceptability curve will be generated using Monte Carlo simulation. If all trial outcomes are similar, the primary analysis will default to a cost-minimization approach. Subgroup analysis will be carried out for patients with and without septic shock at presentation, and for patients whose initial APACHE II scores are > 20 versus ≤ 20. DISCUSSION: In addition to an estimate of the clinical effectiveness of an OA approach for SCIAS, an understanding of its cost effectiveness will be required prior to its adoption in any resource-constrained environment. We will estimate this key parameter for use by clinicians and policymakers. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03163095, registered May 22, 2017.

Closed incision negative pressure therapy: Results of recent trials and recommendations for clinical practice.

BACKGROUND: Open abdominal surgery is associated with high rates of wound complications . Surgical site infection (SSI) is associated with prolonged length of stay, delayed treatment and high rates of readmission (1, 3, 4). Negative pressure wound therapy over closed incisions (ciNPWT) is a novel approach to prevention of SSI. We reviewed the outcomes of studies comparing ciNPWT and standard therapy in open abdominal wounds to assess the efficacy of the current evidence base. AIM: To assess the effect of negative pressure wound therapy used over closed incisions in open abdominal surgery. METHODS: Search of relevant terms was conducted on PubMed, Scopus and Cochrane to identify studies published between Jan 2006-Feb 2019. Studies were chosen based on specific inclusion criteria. Articles were screened to assess demographics, study design and outcomes. RESULTS: Seven retrospective and six prospective randomised controlled trials were identified for inclusion, totalling 3048 participants. 967 received ciNPWT and 2081 received standard treatment. Studies assessed a mix of surgeries (colorectal n = 6, pancreaticoduodenectomy n = 1, gynaecologic n = 1, acute care surgery n = 1, mixed open n = 2). ciNPWT was statistically significant in reducing SSI in 9 of 13 studies. CONCLUSION: ciNPWT in open abdominal surgery has demonstrated promising results for reducing SSI rate in some trials however, patient selection remains unclear. Recent randomized controlled trials have failed to demonstrate benefit overall with use of ciNPWT in open abdominal surgery. Further multicentre prospective trials are needed for cost-benefit analysis and appropriate patient-selection.

Negative pressure wound therapy in elective stoma reversal surgery: results of a UK district general hospital pilot.

The role of negative pressure wound therapy in stoma reversal surgery remains unknown. To evaluate this, a retrospective, non-randomized, single-institution, pilot study was conducted. Surgeon preference determined type of wound closure and application of the single-brand negative wound pressure device. No patient in the intervention group suffered wound complications, but five of the thirty-six patients in the control group suffered surgical site infection-related complications. Primary closure and negative pressure wound therapy use decreases wound complications in stoma reversal surgery, thereby alleviating the wound-management burden in hospitals and in the community. This has cost-saving implications, but further studies are needed.

Cost-effectiveness of negative-pressure wound therapy in adults with severe open fractures of the lower limb: evidence from the WOLLF randomized controlled trial.

AIMS: The aim of this study was to estimate the cost-effectiveness of negative-pressure wound therapy (NPWT) in comparison with standard wound management after initial surgical wound debridement in adults with severe open fractures of the lower limb. PATIENTS AND METHODS: An economic evaluation was conducted from the perspective of the United Kingdom NHS and Personal Social Services, based on evidence from the 460 participants in the Wound Management of Open Lower Limb Fractures (WOLLF) trial. Economic outcomes were collected prospectively over the 12-month follow-up period using trial case report forms and participant-completed questionnaires. Bivariate regression of costs (given in £, 2014 to 2015 prices) and quality-adjusted life-years (QALYs), with multiple imputation of missing data, was conducted to estimate the incremental cost per QALY gained associated with NPWT dressings. Sensitivity and subgroup analyses were undertaken to assess the impacts of uncertainty and heterogeneity, respectively, surrounding aspects of the economic evaluation. RESULTS: The base case analysis produced an incremental cost-effectiveness ratio of £267 910 per QALY gained, reflecting higher costs on average (£678; 95% confidence interval (CI) -£1082 to £2438) and only marginally higher QALYS (0.002; 95% CI -0.054 to 0.059) in the NPWT group. The probability that NPWT is cost-effective in this patient population did not exceed 27% regardless of the value of the cost-effectiveness threshold. This result remained robust to several sensitivity and subgroup analyses. CONCLUSION: This trial-based economic evaluation suggests that NPWT is unlikely to be a cost-effective strategy for improving outcomes in adult patients with severe open fractures of the lower limb. Cite this article: Bone Joint J 2019;101-B:1392-1401.

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.