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

Prospective Comparison of Wound Complication Rates after Elective Open Peripheral Vascular Surgery - Endovascular Versus Open Vascular Surgeons

BACKGROUND

Skill and experience of surgeons are likely to influence the incidence of surgical wound complications (SWC) after open lower limb revascularization. Differences in SWC between surgeons with predominantly endovascular or open vascular surgical profiles could be expected. The aim of this study was to compare SWC rates after elective open vascular surgery between primarily endovascular and primarily open vascular surgeons.

METHODS

Prospective data from patients undergoing elective surgery for peripheral artery disease (PAD) was collected between 2013 and 2019. Senior surgeons were assigned to the open-surgeon or the endo-surgeon group based on the percentage of their open surgical case load during the 6 year study period. SWC was measured by their clinical impact scale (grade 1-outpatient treatment to grade 6-death). Surgical site infection was defined by Additional treatment, Serous discharge, Erythema, Purulent exudate, Separation of deep tissues, Isolation of bacteria, and Stay (ASEPSIS) criteria. Propensity score adjusted analysis (PSAA) was used to account for differences in baseline and perioperative characteristics and expressed as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

The proportion of chronic limb-threatening ischemia (P = 0.001), ipsilateral foot wound (P = 0.012) and femoro-popliteal bypass procedures (P < 0.001) were higher in the open-surgeon group. A lower incidence of SWC according to ASEPSIS criteria (25.6% vs. 38.6%, respectively, P = 0.042) and SWC grade ≥1 (33.7% vs. 51.0%, respectively, P = 0.010) was found in the endo-surgeon group (n = 86) compared to the open-surgeon group (n = 153). These differences disappeared after PSAA (OR 0.63, 95% CI 0.27-1.44, and OR 0.60, 95% CI 0.27-1.33, respectively).

CONCLUSIONS

Patients operated by endo-surgeons had less advanced PAD and lower incidence of SWC compared to those treated by open-surgeons. No difference in SWC remained after PSAA.

Comparison of negative pressure wound therapy against normal dressing after vascular surgeries for inguinal wounds: A systematic review and meta-analysis

Background

Negative Pressure Wound Therapy (NPWT) is a therapeutic technique of applying sub-atmospheric pressure to a wound to reduce inflammation, manage exudate, and promote the formation of granulation tissue. It aims to optimise the natural physiological processes of wound healing for more effective recovery, and NPWT has emerged as a promising alternative to traditional dressings.

Methods

The protocol followed in the study was prospectively registered. Appropriate search terms and Boolean operators were used to search electronic databases for relevant articles. Screening of articles was performed, and data extraction was done. The effect measure was chosen according to the nature of the variable, and the effect model was chosen as per heterogeneity. Forest plot was used to give visual feedback.

Results

This study included 11 randomized controlled trials (13 publications) with a total of 1310 patients (1497 inguinal wounds). The NPWT group had lesser odds of developing surgical site infection (OR: 0.40; 95 % CI: 0.29-0.54; n = 1491; I2 = 20 %; p-value ≤0.00001) and lesser odds of needing surgical wound revision (OR: 0.48; 95 % CI: 0.26-0.91; n = 856; I2 = 0 %; p-value = 0.02) as compared to the normal dressing group. No significant difference was observed in duration of hospital stay, cost of care, wound healing time, or other complications.

Conclusion

NPWT application in inguinal wounds significantly reduces the surgical site infection and the need for wound revision in patients who have undergone vascular surgery.

Multicenter parallel randomized trial evaluating incisional negative pressure wound therapy for the prevention of surgical site infection after lower extremity bypass

OBJECTIVE

Incisional negative pressure wound therapy (iNPWT) applied over all incisions after lower extremity bypass in the prevention of surgical site infections (SSIs) is unclear. The primary and secondary aims of this study were to investigate if prophylactic iNPWT after the elective lower extremity bypass prevents SSI and other surgical wound complications.

METHODS

This was a multicenter, parallel, randomized controlled trial. Patients undergoing elective lower extremity bypass in 3 hospitals were randomized to either iNPWT or standard dressings. SSIs or other wound complications were assessed within the first 90 days by wound care professionals blinded to the randomized result. The validated Additional treatment, Serous discharge, Erythema, Purulent exudate, Separation of deep tissues, Isolation of bacteria, and Stay (ASEPSIS) score was used to objectively assess the wounds. ASEPSIS score ≥21 is defined as an SSI. Unilateral and bilateral groups were analyzed with the Fisher exact test and the McNemar test, respectively.

RESULTS

In the unilateral group (n = 100), the incidence of SSI in the iNPWT group was 34.9% (15/43), compared with 40.3% (23/57) in the control group, according to the ASEPSIS score (P = .678). In the bilateral group (n = 7), the SSI rate was 14.3% (1/7) in the iNPWT group compared with 14.3% (1/7) in the control group (P = 1.00). In the unilateral group, there was a higher wound dehiscence rate in the control group (43.9%) compared with the iNPWT group (23.3%) (P = .0366). No serious iNPWT-related adverse events were recorded.

CONCLUSIONS

There was no reduction of SSI rates in leg incisions with iNPWT compared with standard dressings in patients undergoing elective lower extremity bypass, whereas iNPWT reduced the incidence of wound dehiscence.

Negative-Pressure Wound Therapy for the Management of Complex Surgical Wounds in a Minority Population

Introduction Negative-pressure wound therapy (NPWT) has been used for decades as an established treatment modality for complex wounds, now commonplace in hospitals and various clinical and outpatient settings. Several studies have noted improved healing outcomes with this device, but the current state of literature is in debate on both clinical and economic effectiveness. The use of NPWT can become expensive, largely because of the complexity of wounds and the need for outpatient management, from which a majority of the benefit is derived. This creates a disparity in access to this therapy. A lack of insurance and limited access to healthcare that is present in minority populations contribute to this inequality. Methods We reviewed the clinical courses of eight patients who were treated with NPWT at a single acute care facility in an underserved area caring for a minority population. Results We describe several different anatomic wounds along with details including the size of wounds, number of debridements, length of hospital stay, duration of treatment, and ensuing courses of the minority patients who received NPWT for the entire duration of their wound care course. Conclusions This case series demonstrates desirable wound healing outcomes with the use of NPWT in the minority population. The authors draw attention to the outpatient benefit of this device that may be lost in those with limited insurance in minority populations and seek to encourage further studies in this population in resource-limited settings to determine its true clinical effectiveness.

Influence of Closed-incision Negative Pressure Wound Therapy on Abdominal Site Complications in Autologous Breast Reconstruction

Background

Closed-incision negative pressure wound therapy (ciNPWT) has shown promise in reducing surgical wound complications. Among its numerous benefits, it allows for exudate management and tension offloading from wound edges. The purpose of this systematic review and meta-analysis was to assess the efficacy of prophylactic ciNPWT versus conventional dressings on abdominal donor site complications in microsurgical breast reconstruction (MR).

Methods

A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in January 2023. PubMed and Embase were searched to identify all relevant studies. Data collected included rates of total wound complications, wound dehiscence, infection, seroma, and length of hospital stay.

Results

A total of 202 articles were screened, and eight studies (1009 patients) met the inclusion criteria. Use of ciNPWT was associated with a significantly lower rate of wound dehiscence (OR, 0.53; 95% confidence interval, 0.33-0.85; P = 0.0085, I2 = 0%). There was no significant difference in the rate of total wound complications [odds ratio (OR), 0.63; 95% CI, 0.35-1.14; P = 0.12, I2 = 69%], donor site infection (OR, 0.91; 95% CI, 0.42-1.50; P = 0.47, I2 = 13%), seroma (OR, 0.74; 95% CI, 0.22-2.49; P = 0.63, I2 = 57%), or length of hospital stay (SMD, 0.089; 95% CI, -0.13-0.35; P = 0.37, I2 = 29%).

Conclusions

Although exudate management by ciNPWT fails to reduce surgical site infection, seroma formation, and overall length of stay, ciNPWT tension offloading properties seem to be associated with lower rates of wound dehiscence when compared with conventional dressings in abdominal-based autologous breast reconstruction.

Efficacy of Strategies Intended to Prevent Surgical Site Infection After Lower Limb Revascularization Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

The objective of this study is to evaluate the efficacy of strategies intended to prevent surgical site infection (SSI) after lower limb revascularization surgery.

BACKGROUND

SSIs are common, costly complications of lower limb revascularization surgery associated with significant morbidity and mortality.

METHODS

We searched MEDLINE, EMBASE, CENTRAL, and Evidence-Based Medicine Reviews (inception to April 28, 2022). Two investigators independently screened abstracts and full-text articles, extracted data, and assessed the risk of bias. We included randomized controlled trials (RCTs) that evaluated strategies intended to prevent SSI after lower limb revascularization surgery for peripheral artery disease. We used random-effects models to pool data and GRADE to assess certainty.

RESULTS

Among 6258 identified citations, we included 26 RCTs (n=4752 patients) that evaluated 12 strategies to prevent SSI. Preincision antibiotics [risk ratio (RR)=0.25; 95% CI, 0.11-0.57; n=4 studies; I2 statistic=7.1%; high certainty] and incisional negative-pressure wound therapy (iNPWT) (RR=0.54; 95% CI, 0.38-0.78; n=5 studies; I2 statistic=7.2%; high certainty) reduced pooled risk of early (≤30 days) SSI. iNPWT also reduced the risk of longer-term (>30 days) SSI (pooled-RR=0.44; 95% CI, 0.26-0.73; n=2 studies; I2 =0%; low certainty). Strategies with uncertain effects on risk of SSI included preincision ultrasound vein mapping (RR=0.58; 95% CI, 0.33-1.01; n=1 study); transverse groin incisions (RR=0.33; 95% CI, 0.097-1.15; n=1 study), antibiotic-bonded prosthetic bypass grafts (RR=0.74; 95% CI, 0.44-1.25; n=1 study; n=257 patients), and postoperative oxygen administration (RR=0.66; 95% CI, 0.42-1.03; n=1 study) (low certainty for all).

CONCLUSIONS

Preincision antibiotics and iNPWT reduce the risk of early SSI after lower limb revascularization surgery. Confirmatory trials are required to determine whether other promising strategies also reduce SSI risk.

A Practical Approach to Predicting Surgical Site Infection Risk Among Patients Before Leaving the Operating Room

A surgical site infection (SSI) prediction model that identifies at-risk patients before leaving the operating room can support efforts to improve patient safety. In this study, eight pre-operative and five perioperative patient- and procedure-specific characteristics were tested with two scoring algorithms: 1) count of positive factors (manual), and 2) logistic regression model (automated). Models were developed and validated using data from 3,440 general and oncologic surgical patients. In the automated algorithm, two pre-operative (procedure urgency, odds ratio [OR]: 1.7; and antibiotic administration >2 hours before incision, OR: 1.6) and three intraoperative risk factors (open surgery [OR: 3.7], high-risk procedure [OR: 3.5], and operative time OR: [2.6]) were associated with SSI risk. The manual score achieved an area under the curve (AUC) of 0.831 and the automated algorithm achieved AUC of 0.868. Open surgery had the greatest impact on prediction, followed by procedure risk, operative time, and procedure urgency. At 80% sensitivity, the manual and automated scores achieved a positive predictive value of 16.3% and 22.0%, respectively. Both the manual and automated SSI risk prediction algorithms accurately identified at-risk populations. Use of either model before the patient leaves the operating room can provide the clinical team with evidence-based guidance to consider proactive intervention to prevent SSIs.

Negative Pressure Wound Therapy in Spinal Surgery

Negative pressure wound therapy (NPWT) has demonstrated promise in the management of surgical site infections as well as assisting in surgical wound healing. In this manuscript, we describe the mechanisms and applications of NPWT for surgical wounds and existing evidence for NPWT in cardiac, plastic, and general surgery, followed by a discussion of the emerging evidence base for NPWT in spinal surgery. We also discuss the different applications of NPWT for open wounds and closed incisions, and the promise of newer closed-incision NPWT (ciNPWT) devices. There is nominal but promising prospective evidence on NPWT's efficacy in select at-risk populations for post-operative wound complications after spinal surgery. As there is currently a paucity of robust clinical evidence on its efficacy, rigorous randomized prospective clinical trials are needed.

A Cost-Utility Analysis of the Use of Closed-Incision Negative Pressure System in Vascular Surgery Groin Incisions

OBJECTIVE

Closed-incision negative pressure therapy (CINPT) with the Prevena system has been used and clinically evaluated in high-risk groin incisions to reduce the risk of postoperative complications. We performed a cost-effectiveness analysis evaluating CINPT in femoral-popliteal bypass with prosthetic graft.

METHODS

A literature review looking at prospective randomized trials determined the probabilities and outcomes for femoral-popliteal bypass with and without CINPT. Reported utility scores were used to estimate the quality adjusted life years (QALYs) associated with a successful procedure and postoperative complications. Medicare current procedure terminology and diagnosis-related group codes were used to assess the costs for a successful surgery and associated complications. A decision analysis tree was constructed with rollback analysis to highlight the more cost-effective strategy. An incremental cost-effectiveness ratio (ICER) analysis was performed with a willingness to pay at $50,000. Deterministic and probabilistic sensitivity analyses were performed to validate the robustness of the results, and to accommodate for the uncertainty in the literature.

RESULTS

Femoral-popliteal bypass with CINPT is less costly ($40,138 vs $41,774) and more effective (6.14 vs 6.13) compared to without CINPT. This resulted in a negative ICER of -234,764.03, which favored CINPT, indicating a dominant strategy. In one-way sensitivity analysis, surgery without CINPT was more cost-effective if the probability of successful surgery falls below 84.9% or if the cost of CINPT exceeds $3139. Monte Carlo analysis showed a confidence of 99.07% that CINPT is more cost-effective.

CONCLUSIONS

Despite the added device cost of CINPT, it is cost-effective in vascular surgical operations using groin incisions.

Single use negative pressure wound therapy in vascular patients: clinical and economic outcomes

OBJECTIVE

Surgical site complications (SSCs) such as dehiscence and infection are a common issue within vascular surgeries and are a key concern to payers and clinicians. It is estimated that occurrence of complications in vascular surgery can increment length of stay by 9.72 days and costs by £3776 per episode. The objective of this research was to determine the clinical and economic impact of the prophylactic use of single use negative pressure wound therapy (sNWPT) in postoperative femoral endarterectomy incisions within a single centre in the Netherlands.

METHOD

Data were extracted retrospectively from the medical notes of patients consecutively treated for femoral endarterectomy between January 2013 and December 2019 in a single centre in the Netherlands. Since August 2016, patients were treated with the sNPWT device and their data were compared with that of patients treated before the introduction of the device. Data were extracted on SSCs and associated healthcare resource use, with comparisons made between the two patient groups.

RESULTS

The study included a cohort of 108 patients. Data of patients treated by standard care (n=64) showed 32 (50%) patients developed complications. This reduced significantly in patients treated with the sNPWT device (n=44) of whom eight (18.2%) developed a postoperative complication (p=0.0011). Average postoperative costs per patient were €3119 for those in the standard care group and €2630 where the sNPWT device was used.

CONCLUSION

sNPWT provided clinical and economic benefits over standard care in the treatment of femoral endarterectomy patients, significantly reducing rate of complication and their associated costs.