Negative-Pressure Wound Therapy for Prevention of Sternal Wound Infection after Adult Cardiac Surgery: Systematic Review and Meta-Analysis

Closed-incision negative pressure therapy as a strategy to reduce sternal wound infection in identified high-risk patients: a multicentre propensity matched study

OBJECTIVES

The premise of this retrospective study was to evaluate the intraoperative use of closed-incision negative pressure therapy (ciNPT) to help reduce the incidence of postoperative sternal wound infections in multimorbid patients with an elevated risk of developing a sternal wound infection post cardiac surgery versus a cohort that received standard-of-care dressings.

METHODS

Data for all adult patients were collected from each cardiothoracic surgery unit across 3 hospitals in the United Kingdom. High-risk patients had 2 or more recognized risk factors. Fisher's exact test (two-tailed) and unpaired t-test were used to help analyse categorical and continuous data. Propensity matching was performed to compare the 2 groups.

RESULTS

A total of 5,288 patients who had cardiac surgery were included. Propensity matching led to 766 matched cases. There were significantly fewer sternal wound infections in the ciNPT group [43 (5.6%) vs 119 (15.5%) cases; P = 0.0001], as well as fewer deep sternal wound infections [14 (1.8%) vs 31 (4.0%) cases; P = 0.0149] and superficial sternal wound infections [29 (3.8%) vs 88 (11.4%) cases; P = 0.0001]. A higher mean length of stay in the ciNPT group was statistically significant (11.23 ± 13 vs 9.66 ± 10 days; P = 0.0083) as was a significantly higher mean logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) (11.143 ± 13 vs 8.094 ± 11; P = 0.0001). A statistically significant higher readmission to the intensive care unit due to sternal wound infection was noted for the controls [16 (2.08%) vs 3 (0.39%) readmissions; P = 0.0042].

CONCLUSIONS

The ciNPT appears to be an effective intervention to help reduce the incidence of sternal wound infection in high-risk individuals undergoing cardiac surgery.

Surgical site infection outcomes of two different closed incision negative pressure therapy systems in cardiac surgery: Systematic review and meta-analysis

Closed incision negative pressure therapy (ciNPT) system use compared with standard of care dressings (SOC) on surgical site infection (SSI) in cardiac surgery was assessed. A systematic literature review was conducted. Risk ratios (RR) and random effects models were used to assess ciNPT with foam dressing (ciNPT-F) or multilayer absorbent dressing (ciNPT-MLA) versus SOC. Health economic models were developed to assess potential per patient cost savings. Eight studies were included in the ciNPT-F analysis and four studies were included in the ciNPT-MLA analysis. For ciNPT-F, a significant reduction in SSI incidence was observed (RR: 0.507, 95% confidence interval [CI]: 0.362, 0.709; p < 0.001). High-risk study analysis reported significant SSI reduction with ciNPT-F use (RR: 0.390, 95% CI: 0.205, 0.741; p = 0.004). For ciNPT-MLA, no significant difference in SSI rates were reported (RR: 0.672, 95% CI: 0.276, 1.635; p = 0.381). Health economic modelling estimated a per patient cost savings of $554 for all patients and $3242 for the high-risk population with ciNPT-F use. Health economic modelling suggests ciNPT-F may provide a cost-effective solution for sternotomy incision management. However, limited high-quality literature exists. More high-quality evidence is needed to fully assess the impact of ciNPT use following cardiac surgery.

Temporal Cluster Analysis of Deep Sternal Wound Infection in a Regional Quality Collaborative

INTRODUCTION

Deep sternal wound infection (DSWI) is a rare complication associated with high mortality. Seasonal variability in surgical site infections has been demonstrated, however, these patterns have not been applied to DSWI. The purpose of this study was to assess temporal clustering of DSWIs.

METHODS

All cardiac surgery patients who underwent sternotomy were queried from a regional Society of Thoracic Surgeons database from 17 centers from 2001 to 2019. All patients with the diagnosis of DSWI were then identified. Cluster analysis was performed at varying time intervals (monthly, quarterly, and yearly) at the hospital and regional level. DSWI rates were calculated by year and month, and compared using mixed-effects negative binomial regression.

RESULTS

A total of 134,959 patients underwent a sternotomy for cardiac surgery, of whom 469 (0.35%) developed a DSWI. Rates of DSWI per hospital across all years ranged from 0.12% to 0.69%. Collaborative-level rates of DSWIs were the greatest in September (0.44%) and the lowest in January (0.30%). Temporal clustering was not seen across seasonal quarters (high rate in preceeding quarter was not associated with a high rate in the next quarter) (P = 0.39). There were yearly differences across all institutions in the DSWI rates. A downward trend in DSWI rates was seen from 2001 to 2019 (P < 0.001). A difference among hospitals in the cohort was observed (P < 0.001).

CONCLUSIONS

DSWI are a rare event within our region. Unlike other surgical site infection, there does not appear to be a seasonal pattern associated with DSWI.

Coronary artery bypass grafting using bilateral internal thoracic arteries in patients with diabetes and obesity: A systematic review and meta-analysis

Background

Patients with diabetes and obesity are at higher risk of adverse long-term outcomes following coronary artery bypass grafting. The use of bilateral internal thoracic arteries (BITA) can potentially offer survival benefit in higher risk patients compared to single internal thoracic artery (SITA), but BITA is not routinely used due to lack of clear evidence of efficacy and concerns over sternal wound complications.

Methods

Medline, Embase and the Cochrane Library were searched for studies comparing the efficacy and safety of BITA and SITA grafting in patients with diabetes and obesity. Meta-analysis of mortality and sternal wound complications was performed.

Results

We identified eight observational and ten propensity matched studies, and one RCT, comparing BITA and SITA which included patients with diabetes (n = 19,589); two propensity matched studies and one RCT which included patients with obesity (n = 6,972); mean follow up was 10.5 and 11.3 years respectively. Meta-analysis demonstrated a mortality reduction for BITA compared to SITA in patients with diabetes (risk ratio [RR] 0.79; 95% confidence interval [CI] 0.70-0.90; p = 0.0003). In patients with obesity there was a non-significant reduction in mortality in the BITA group (RR 0.73, 95% CI 0.47-1.12; p = 0.15). There was a significantly higher rate of sternal wound complications following BITA observed in patients with diabetes (RR 1.53, 95% CI 1.23-1.90; p = 0.0001) and obesity (RR 2.24, 95% CI 1.63-3.07; p < 0.00001).

Conclusions

BITA is associated with better long-term survival in patients with diabetes. The effects of BITA grafting in patients with obesity are uncertain. BITA is associated with higher rates of sternal wound complications compared to SITA in both patients with diabetes and obesity.

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.