Predictors of surgical site infection after open lower extremity revascularization

Mortality and Morbidity After Open Surgical Lower Extremity Revascularization in Patients With Peripheral Artery Disease and Concurrent Abdominal Stoma

OBJECTIVES

Patients with peripheral artery disease (PAD) often require treatment with open lower extremity revascularization (LER). Patients with PAD often have other comorbidities and associated conditions that affect procedural outcomes, including abdominal stomas. The aim of this work is to investigate the impact that stomas may have on postoperative outcomes and complications.

METHODS

We performed a 5-year (2016-2020) analysis of the Nationwide Readmission Database. We identified all adult patients undergoing open LER. These patients were categorized into 2 groups: stoma and no-stoma. Propensity score matching (1:1) was used to control for demographics and comorbidities. Index admission outcomes and readmission rate were examined.

RESULTS

212,275 open LER patients were identified. A matched cohort of 3088 patients (1:1 stoma vs no-stoma) was obtained. Patients with stomas had higher rates of several postoperative complications: acute posthemorrhagic anemia (29.1%, P < 0.01), acute kidney injury (21.4%, P < 0.001), index sepsis (10.3%, P < 0.001), and index SSI (2.8%, P < 0.001). There were no significant statistical differences between the 2 groups for acute myocardial infarction. Those with stomas had worse outcomes: greater in-hospital mortality (4.7%, P < 0.05), length of stays (median 7 days, P < 0.001), total charges (median 108,037 dollars, P < 0.001), discharges to long-term care facilities (30.8%, P < 0.001), discharges to their own homes needing home health care (30.1%, P < 0.001), 30-day readmission rates (23.2%, P < 0.01), and 30-day readmission mortality (6.1%, P < 0.01).

CONCLUSIONS

Concurrent abdominal stoma is associated with increased postoperative morbidity and mortality after open LER. Further prospective studies are needed to validate these results.

From basic research to clinical practice: The impact of laminar airflow filters on surgical site infection in vascular surgery

BACKGROUND

Laminar airflow filters have been suggested as a potential preventive factor for surgical site infections, given their ability to reduce the airborne microbiological load. However, their role is still unclear, and evidence regarding vascular surgery patients is scarce. Our aim was to assess the impact of laminar-airflow filters on surgical site infections.

METHODS

This single-centre retrospective cohort study was conducted with vascular surgery patients who underwent arterial vascular intervention through a groin incision between July 2018 and July 2019 (turbulent airflow cohort) and July 2020 and July 2021 (laminar airflow cohort). Data were prospectively collected from electronic medical files. We estimated the cumulative incidence of surgical site infections and its 95% confident interval (95%CI). A propensity score matching analysis was performed.

RESULTS

We included 200 patients, 78 in the turbulent airflow cohort and 122 in the laminar airflow cohort. The cumulative incidence was 15.4% (12/78; 95%CI: 9.0-25.0%) in the turbulent-airflow cohort and 14.8% (18/122; 95%CI: 9.5 -22.1%) in the laminar-airflow cohort (p-value: 1.00). The propensity score matching yielded a cumulative incidence of surgical site infection of 13.9% (10/72) with turbulent airflow and 12.5% (9/72) with laminar airflow (p-value: 1.00). Risk factors associated with infection were chronic kidney disease (OR 2.70; 95%CI: 1.14-6.21) and a greater body mass index (OR 1.47; 95%CI: 1.01-2.14).

CONCLUSION

Laminar airflow filters were associated with a non-significant reduction of surgical site infections. Further research is needed to determine its usefulness and cost-effectiveness. Surgical site infection incidence was associated with chronic kidney disease and a greater body mass index. Hence, efforts should be made to optimize the body mass index before surgery and prevent chronic kidney disease in patients with known arterial disease.

A systematic review and meta-analysis of outcomes associated with development of surgical site infection after lower-limb revascularization surgery

OBJECTIVES

Although surgical site infection (SSI) is a commonly used quality metric after lower-limb revascularization surgery, outcomes associated with development of this complication are poorly characterized. We conducted a systematic review and meta-analysis of studies reporting associations between development of an SSI after these procedures and clinical outcomes and healthcare resource use.

METHODS

We searched MEDLINE, Embase, CENTRAL, and Evidence-Based Medicine Reviews (inception to April 4th, 2023) for studies examining adjusted associations between development of an SSI after lower-limb revascularization surgery and clinical outcomes and healthcare resource use. Two investigators independently screened abstracts and full-text citations, extracted data, and assessed risk of bias. Data were pooled using random-effects models. Heterogeneity was assessed using I2 statistics. GRADE was used to assess estimate certainty.

RESULTS

Among 6671 citations identified, we included 11 studies (n = 61,628 total patients) that reported adjusted-associations between development of an SSI and 13 different outcomes. Developing an SSI was associated with an increased adjusted-risk of hospital readmission (pooled adjusted-risk ratio (aRR) = 3.55; 95% CI (confidence interval) = 1.40-8.97; n = 4 studies; n = 13,532 patients; I2 = 99.0%; moderate certainty), bypass graft thrombosis within 30-days (pooled aRR = 2.09; 95% CI = 1.41-3.09; n = 2 studies; n = 23,240 patients; I2 = 51.1%; low certainty), reoperation (pooled aRR = 2.69; 95% CI = 2.67-2.72; n = 2 studies; n = 23,240 patients; I2 = 0.0%; moderate certainty), bleeding requiring a transfusion or secondary procedure (aRR = 1.40; 95% CI = 1.26-1.55; n = 1 study; n = 10,910 patients; low certainty), myocardial infarction or stroke (aRR = 1.21; 95% CI = 1.02-1.43; n = 1 study; n = 10,910 patients; low certainty), and major (i.e., above-ankle) amputation (pooled aRR = 1.93; 95% CI = 1.26-2.95; n = 4 studies; n = 32,859 patients; I2 = 83.0; low certainty). Development of an SSI >30-days after the index operation (aRR = 2.20; 95% CI = 1.16-4.17; n = 3 studies; n = 21,949 patients; low certainty) and prosthetic graft infection (aRR = 6.72; 95% CI = 3.21-12.70; n = 1 study; n = 272 patients; low certainty) were both associated with an increased adjusted-risk of major amputation. Prosthetic graft infection was also associated with an increased adjusted-risk of mortality >30-days after the index procedure (aRR = 6.40; 95% CI = 3.32-12.36; n = 1 study; n = 272 patients; low certainty).

CONCLUSIONS

This systematic review and meta-analysis suggests that development of an SSI after lower-limb revascularization surgery significantly increases patient morbidity and healthcare resource use. SSI is therefore a valuable quality metric after these surgeries. However, current estimates are based on heterogenous, low-to-moderate certainty evidence and should be confirmed by large, multicenter, cohort studies.

Impact of Wound Closure Technique on Surgical Site Infection After Lower Extremity Bypass Surgery

BACKGROUND

Surgical site infections (SSIs) are among the most common complications after lower extremity bypass (LEB). Both patient and hospital-related factors have been associated with SSI after LEB; however, the impact of surgical closure technique on SSI incidence remains unclear.

METHODS

Institutional electronic medical records (EMRs) were retrospectively queried for all LEB procedures performed from 2018 to 2022. Data were collected on patient demographics, medical comorbidities, operative details, wound closure techniques, and postoperative outcomes. Closure techniques included skin staples, absorbable monofilament (Monocryl), nonabsorbable monofilament (Nylon), or left open to heal by secondary intention. Logistic regression analysis was utilized to identify risk factors and calculate adjusted odds ratios (ORs) for postoperative SSI.

RESULTS

A total of 517 patients underwent LEB surgery over the study period. SSI was diagnosed in 120 (23.2%) patients over a median follow-up period of 1.5 years. The most common SSI locations were groin incision (40.0%), saphenectomy (31.7%), and leg incision (19.2%). The median onset of SSI was 18.5 d (interquartile range [IQR] 11-28 d) post-LEB surgery. Patients with SSI had higher body mass index (BMI) (28.2 [IQR 24.2-33.5] vs. 26.6 [23.1-31.5] kg/m2, P = 0.03) compared with non-SSI patients. Patient age, sex, and medical comorbidities were otherwise similar between groups. There were no differences in closure technique (79.2% vs. 78.1% staples, 18.3% vs. 19.7% Monocryl, 0.8% vs. 1.8% Nylon, 1.7% vs. 0.5% open; P = 0.53) in SSI versus non-SSI groups. On multivariate analysis, patient BMI (OR 1.04 per unit, 95% confidence interval [CI] 1.01-1.08, P = 0.02), reoperative field (OR 1.81, 95% CI 1.00-3.25, P = 0.03), and active smoking (OR 2.72, 95% CI 1.12-6.59, P = 0.048) were independently associated with increased SSI incidence. Postoperative SSI resulted in prolonged hospital length of stay (LOS) (7 vs. 6 days, P = 0.04), unplanned hospital readmission (49.2% vs. 12.3%, P < 0.001), and reoperation rates (64.7% vs. 8.1%, P < 0.001). Bypass graft infection rates were also higher among patients suffering postoperative SSI (9.2% vs. 0.0%, P < 0.001). On subset analysis of patients at increased risk of postoperative SSI, as found on multivariate modeling, there were no differences in closure technique between SSI and no SSI groups.

CONCLUSIONS

This study provides insights on wound closure techniques and postoperative SSI made available through granular, operative data that are not found in large database analyses. Surgical wound closure technique was not associated with postoperative SSI after LEB surgery, even among patients at increased risk of infection. These data support individualization of wound closure techniques among patients undergoing LEB surgery.

Current Applications and Future Perspectives of Artificial and Biomimetic Intelligence in Vascular Surgery and Peripheral Artery Disease

Artificial Intelligence (AI) made its first appearance in 1956, and since then it has progressively introduced itself in healthcare systems and patients' information and care. AI functions can be grouped under the following headings: Machine Learning (ML), Deep Learning (DL), Artificial Neural Network (ANN), Convolutional Neural Network (CNN), Computer Vision (CV). Biomimetic intelligence (BI) applies the principles of systems of nature to create biological algorithms, such as genetic and neural network, to be used in different scenarios. Chronic limb-threatening ischemia (CLTI) represents the last stage of peripheral artery disease (PAD) and has increased over recent years, together with the rise in prevalence of diabetes and population ageing. Nowadays, AI and BI grant the possibility of developing new diagnostic and treatment solutions in the vascular field, given the possibility of accessing clinical, biological, and imaging data. By assessing the vascular anatomy in every patient, as well as the burden of atherosclerosis, and classifying the level and degree of disease, sizing and planning the best endovascular treatment, defining the perioperative complications risk, integrating experiences and resources between different specialties, identifying latent PAD, thus offering evidence-based solutions and guiding surgeons in the choice of the best surgical technique, AI and BI challenge the role of the physician's experience in PAD treatment.

A Meta-Analysis to Derive Population-Based Quality Benchmarks of the Incidence of Surgical Site Infection after Lower Limb Revascularization Surgery

BACKGROUND

The reported incidence of surgical site infection (SSI) after lower limb revascularization surgery varies. We conducted a systematic review and meta-analysis of population-based studies reporting the incidence of SSI in adults who underwent these surgeries in high-income countries to derive SSI quality benchmarks.

METHODS

We searched MEDLINE, EMBASE, CENTRAL, and Evidence-Based Medicine Reviews (inception-to-April 28th, 2022) for population-based studies estimating the cumulative incidence of SSI among adults who underwent lower limb revascularization surgery for peripheral artery disease (PAD) in high-income countries. Two investigators independently screened abstracts and full-text articles, extracted data, and assessed risks of bias. We used random-effects models to pool data and GRADE to assess certainty.

RESULTS

Among 6,258 citations, we included 53 studies (n = 757,726 patients); 8 of which (n = 435,769 patients) reported nonoverlapping data that were meta-analyzed. The pooled cumulative incidence of any SSI was 6.0 in 100 patients [95% confidence interval (CI) = 4.3-8.0 in 100 patients; n = 8 studies; n = 435,769 patients; moderate certainty]. The cumulative incidence of Szilagyi grade I (cellulitis), grade II (subcutaneous tissue), and grade III (prosthetic graft) SSI was 6.5 in 100 patients (95% CI = 4.3-8.6 in 100 patients; n = 2 studies; n = 39,645 patients; low certainty), 2.1 in 100 patients (95% CI = 2.0-2.3 in 100 patients; n = 2 studies; low certainty), and 0.4 in 100 patients (95% CI = 0.4-0.4 in 100 patients; n = 1 study; n = 333,275 patients; low certainty), respectively. The pooled cumulative incidence of any early (in-hospital/≤30-days) and late (>30-days) SSI was 6.2 in 100 patients (95% CI = 4.4-8.0 in 100 patients; n = 7 studies; n = 431,273 patients; moderate certainty) and 3.7 in 100 patients (95% CI = 2.2-5.2 in 100 patients; n = 2 studies; n = 10,565 patients; low certainty), respectively.

CONCLUSIONS

This systematic review derived population-based benchmarks of the incidence of any SSI; Szilagyi I, II, and III SSI; and early and late SSI after lower limb revascularization surgery. These may be used by practicing surgeons and healthcare leaders/administrators to guide quality improvement efforts in the United States and perhaps other countries.

Risk Factors for Surgical Site Infection after Lower Limb Revascularisation Surgery: a Systematic Review and Meta-Analysis of Prognostic Studies

OBJECTIVE

To systematically review and meta-analyse adjusted risk factors for surgical site infection (SSI) after lower limb revascularisation surgery.

DATA SOURCES

MEDLINE, Embase, Evidence Based Medicine Reviews, and the Cochrane Central Register of Controlled Trials (inception to 28 April 2022).

REVIEW METHODS

Systematic review and meta-analysis conducted according to PRISMA guidelines. After protocol registration, databases were searched. Studies reporting adjusted risk factors for SSI in adults who underwent lower limb revascularisation surgery for peripheral artery disease were included. Adjusted odds ratios (ORs) were pooled using random effects models. GRADE was used to assess certainty.

RESULTS

Among 6 377 citations identified, 50 studies (n = 271 125 patients) were included. The cumulative incidence of SSI was 12 (95% confidence interval [CI] 10 - 13) per 100 patients. Studies reported 139 potential SSI risk factors adjusted for a median of 12 (range 1 - 69) potential confounding factors. Risk factors that increased the pooled adjusted odds of SSI included: female sex (pooled OR 1.41, 95% CI 1.20 - 1.64; high certainty); dependent functional status (pooled OR 1.18, 95% CI 1.03 - 1.35; low certainty); being overweight (pooled OR 1.82, 95% CI 1.29 - 2.56; moderate certainty), obese (pooled OR 2.20, 95% CI 1.44 - 3.36; high certainty), or morbidly obese (pooled OR 1.65, 95% CI 1.08 - 2.52; moderate certainty); chronic obstructive pulmonary disease (pooled OR 1.42, 95% CI 1.17 - 1.71; high certainty); chronic limb threatening ischaemia (pooled OR 1.67, 95% CI 1.22 - 2.29; moderate certainty); chronic kidney disease (pooled OR 2.13, 95% CI 1.18 - 3.83; moderate certainty); intra-operative (pooled OR 1.23, 95% CI 1.02 - 1.49), peri-operative (pooled OR 1.92, 95% CI 1.27 - 2.90), or post-operative (pooled OR 2.21, 95% CI 1.44 - 3.39) blood transfusion (moderate certainty for all); urgent or emergency surgery (pooled OR 2.12, 95% CI 1.22 - 3.70; moderate certainty); vein bypass and or patch instead of endarterectomy alone (pooled OR 1.86, 95% CI 1.33 - 2.59; moderate certainty); an operation lasting ≥ 3 hours (pooled OR 1.86, 95% CI 1.33 - 2.59; moderate certainty) or ≥ 5 hours (pooled OR 1.60, 95% CI 1.18 - 2.17; moderate certainty); and early or unplanned re-operation (pooled OR 4.50, 95% CI 2.18 - 9.32; low certainty).

CONCLUSION

This systematic review identified evidence informed SSI risk factors following lower limb revascularisation surgery. These may be used to develop improved SSI risk prediction tools and to identify patients who may benefit from evidence informed SSI prevention strategies.

Investigation of center-specific saphenous vein utilization rates in femoral popliteal artery bypass and associated impact of conduit on outcomes

OBJECTIVE

The purpose of this study is to investigate variation in great saphenous vein (GSV) use among the various centers participating in the Vascular Quality Initiative infrainguinal bypass modules. Further, differences in outcomes in femoral-popliteal artery bypass with single segment GSV conduit vs prosthetic conduit will be documented. Center GSV use rate impact on outcomes will be investigated.

METHODS

Primary exclusions were patients undergoing redo bypass, urgent or emergent bypass, and those in whom prosthetic graft was used while having undergone prior coronary artery bypass grafting. The distribution of GSV use across the 260 centers participating in Vascular Quality Initiative infrainguinal bypass module was placed into histogram and variance in mean GSV use evaluated with analysis of variance analysis. Centers that used GSV in >50% of bypasses were categorized as high use centers and centers that used the GSV in <30% of cases were categorized as low use centers. Baseline differences in patient characteristics and comorbidities in those undergoing bypass with GSV vs prosthetic conduit were analyzed with χ2 testing and the Student t test, as were those undergoing treatment in high vs low use centers. Multivariable time-dependent Cox regression analyses were then performed for the primary outcomes of major amputation ipsilateral to the operative side and mortality in long-term follow-up. High vs low use center was a dichotomous variable in these regressions. Secondary outcomes of freedom from graft infection and freedom from loss of primary patency were performed with Kaplan-Meier analysis.

RESULTS

Among centers with >50 patients meeting inclusion criteria for this study, GSV use ranged from 15% to 93% (analysis of variance P < .001). When considering all centers irrespective of number of patients, the range was 0% to 100%. On Kaplan-Meier analysis, GSV conduit use was associated with improved freedom from loss of primary or primary assisted patency, improved freedom from major amputation after index hospitalization, improved freedom from graft infection after the index hospitalization, and improved freedom from mortality in long-term follow-up (log-rank P < .001 for all four outcomes). Both low use center (hazard ratio, 1.35; P < .001) and prosthetic graft use (hazard ratio, 1.24; P < .001) achieved multivariable significance as risks for mortality in long-term follow-up. Other variables with a multivariable mortality association are presented in the manuscript. Low use center and prosthetic bypass were significant univariable but not multivariable risks for major amputation after index hospitalization.

CONCLUSIONS

There is remarkably wide variation in GSV use for femoral popliteal artery bypass among various medical centers. GSV use is associated with enhanced long-term survival as well as freedom from loss of bypass patency and graft infection. The data herein indicate institutional patterns of prosthetic conduit choice, which has the potential to be altered to enhance outcomes.

Predictors of in-hospital surgical site infections in surgically managed acetabular fractures: A nationwide analysis

Background

A surgical site infection (SSI) rate of 4%-8% has been reported in patients who undergo open reduction and internal fixation (ORIF) for acetabular fractures. Studies have identified risk factors for SSI, but none have performed a nationwide analysis of SSI in surgically managed acetabular fracture patients.

Methods

The National Inpatient Sample (NIS) database was queried for patients who underwent ORIF for acetabular fractures from 2016 to 2019. Analysis was performed on all patients who underwent ORIF for acetabular fractures, as well as those who only underwent ORIF for isolated acetabular fractures. Clinical characteristics, hospital course, discharge disposition, and hospitalization costs were compared between groups. Multivariate regression analysis was conducted to assess predictors of SSI.

Results

41,725 patients undergoing acetabular fracture repair were identified, of which 490 (1.2%) developed SSI during hospitalization. Age (45.90 vs 49.90, p < 0.001) and Injury Severity Scale (5.99 vs 8.30, p < 0.001) were increased in patients who developed SSI. History of hypertension (HTN) (OR = 2.343, 95% CI 1.96-2.80, p < 0.001), longer hospital length of stay (30.27 days vs 10.00 days, p < 0.001) and total charges ($469,005 vs $193,032, p < 0.001) were associated with SSI. Lower rates of routine discharge were seen in SSI patients (OR = 0.333, 95% CI 0.260-0.426, p < 0.001). Higher rates of inpatient death were associated with SSI (OR = 2.210, 95% CI 1.172-4.17, p = 0.019). Multiple procedures in addition to acetabular fracture repair, iliac artery embolization, substance abuse, later time to internal fixation and HTN were predictive of SSI (p < 0.001).

Conclusions

Severity of injury, time to fixation, and factors associated with compromised cardiovascular integrity were predictors of SSI. Identifying patients at risk for SSI should lead to clinical maneuvers that may optimize outcome.

Application of targeted maximum likelihood estimation in public health and epidemiological studies: a systematic review

PURPOSE

The targeted maximum likelihood estimation (TMLE) statistical data analysis framework integrates machine learning, statistical theory, and statistical inference to provide a least biased, efficient, and robust strategy for estimation and inference of a variety of statistical and causal parameters. We describe and evaluate the epidemiological applications that have benefited from recent methodological developments.

METHODS

We conducted a systematic literature review in PubMed for articles that applied any form of TMLE in observational studies. We summarized the epidemiological discipline, geographical location, expertize of the authors, and TMLE methods over time. We used the Roadmap of Targeted Learning and Causal Inference to extract key methodological aspects of the publications. We showcase the contributions to the literature of these TMLE results.

RESULTS

Of the 89 publications included, 33% originated from the University of California at Berkeley, where the framework was first developed by Professor Mark van der Laan. By 2022, 59% of the publications originated from outside the United States and explored up to seven different epidemiological disciplines in 2021-2022. Double-robustness, bias reduction, and model misspecification were the main motivations that drew researchers toward the TMLE framework. Through time, a wide variety of methodological, tutorial, and software-specific articles were cited, owing to the constant growth of methodological developments around TMLE.

CONCLUSIONS

There is a clear dissemination trend of the TMLE framework to various epidemiological disciplines and to increasing numbers of geographical areas. The availability of R packages, publication of tutorial papers, and involvement of methodological experts in applied publications have contributed to an exponential increase in the number of studies that understood the benefits and adoption of TMLE.

Investigating glycemic control in patients undergoing lower extremity bypass within an enhanced recovery pathway at a single institution

BACKGROUND

Enhanced recovery pathways (ERPs) aim to lower perioperative stress to facilitate recovery. Limited fasting combined with carbohydrate loading is a common ERP element. The effect of limited fasting has not been elucidated in patients with diabetes. Given the known deleterious effects of poor glycemic control in the perioperative period, such as increased rates of surgical site infection, the associations of preoperative limited fasting with perioperative glycemic control and early outcomes after lower extremity bypass (LEB) were investigated.

METHODS

A single institutional retrospective review of patients who underwent infrainguinal LEB from 2016 to 2022 was performed. The ERP was initiated in May 2018. Patients were stratified by diabetes diagnosis and preoperative hemoglobin A1C (HbA1C) levels. Perioperative glycemic control was compared between the limited fasting and traditional fasting patients (nil per os at midnight). Limited fasting was defined as a clear liquid diet until 2 hours before surgery with recommended carbohydrate loading consisting of 400 cc of a clear sports drink (approximately 30 g of carbohydrates). All limited fasting patients were within the ERP. Early perioperative hyperglycemia (EPH) was defined as blood glucose of >180 mg/dL within the first 24 hours of surgery. Perioperative outcomes such as surgical site infection, readmission, reinterventions, and complications were also compared.

RESULTS

A total of 393 patients were included (limited fasting patients N = 135; traditional fasting patients N = 258). A trend toward EPH was seen in all limited fasting groups. Evaluating limited fasting within diabetic patients revealed that 74.5% of limited fasting-diabetic patients had EPH compared with 49.6% of traditional fasting-diabetic patients (P = .001). When stratified by the HbA1C level, a significantly higher rate of EPH was seen in the HbA1c >8.0% groups, with 90.5% in the limited fasting patients compared with 67.9% in traditional fasting patients (P = .05). Limited fasting-diabetic patients experience a longer postoperative length of stay at 5.0 days (interquartile range: 3, 9) vs 4.0 days (2, 6) in nondiabetic patients (P = .016).

CONCLUSIONS

ERP limited fasting was associated with early perioperative hyperglycemia after LEB, particularly in patients with HbA1C >8.0%. Due to the high prevalence of diabetic patients undergoing LEB under ERP, the role of limited fasting and common glycemic elements of ERP may need to be re-evaluated in this subpopulation.

Severe local wound infections after vascular exposure in the groin and other body areas: Prevention, treatment and prognosis

Severe surgical site infections (SSIs) are a frequent nosocomial complication after vascular interventions, an important cause of postoperative morbidity, and a substantial burden to the health care system. Patients undergoing arterial interventions are at elevated risk of SSIs, possibly because of the presence of several risk factors in this patient population. In this review, we examined the available clinical evidence for the prevention, treatment, and prognostication of postoperative severe SSIs after vascular exposure in the groin and other body areas. Results from studies evaluating preoperative, intraoperative, and postoperative preventive strategies and several treatment options are reviewed. In addition, risk factors for surgical wound infections are analyzed in detail and related evidence from the literature is highlighted. Although several measures have been implemented over the time to prevent them, SSIs continue to pose a substantial health care and socioeconomic challenge. Therefore, strategies to decrease the risk and improve the treatment of SSIs for the high-risk vascular patient population should be the focus of continuing improvement and critical review. This review aimed at identifying and reviewing the current evidence for preventing, treating, and performing stratification according to the prognosis of postoperative severe SSIs after vascular exposure in the groin and other body areas.

American Society of Anesthesiologists-Physical Status Classification As An Independent Risk Factor of Surgical Site Infection After Infra-Inguinal Arterial Bypass

OBJECTIVES

The present study aimed to assess whether high-risk American Society of Anesthesiologists (ASA)-Physical Status was an independent risk factor for the development of surgical site infection (SSI) after infra-inguinal lower extremity bypass (LEB).

SUMMARY OF BACKGROUND DATA

The ASA-Physical Status Classification System assesses the overall physical status preoperatively. ASA-Physical Status is associated with postoperative morbidity and mortality. However, limited data are available on how ASA-Physical Status Class affects the development of SSI after infra-inguinal LEB.

METHODS

Patients who had undergone infra-inguinal LEB from January 1, 2015 to December 31, 2018, for obliterative arteriopathy or popliteal aneurysm at our university hospital were included. SSI risk factors were identified using multivariable logistic regression. The length of hospital stay, major limb events (MALE), major adverse cardiovascular events (MACE), and all-cause mortality were compared for patients with SSI versus those without SSI 3 months and 1- year of follow-up after the index surgery.

RESULTS

Among the 267 patients included, 30 (11.2%) developed SSI during the 3-month period and 32 (12%) at 1 year. ASA-Physical Status ≥3 [odds ratio (OR): 3.7, 95% confidence interval CI) 1.5-11.1], emergency surgery (OR: 2.7, 95% CI 1.2-6.0), general anesthesia (OR: 2.8, 95% CI 1.3-6.1), and procedure performed by a junior surgeon (OR: 2.7, 95% CI 1.3-6.0) were independently associated with SSI. At 3 months and 1 year, SSI was significantly associated with MALE (including surgical wound debridement, subsequent thrombectomy, major amputation), length of hospital stay, and all-cause mortality.

CONCLUSION

The ASA-Physical Status should be considered in medical management when an infra-inguinal LEB is considered in frail patients, to prevent surgical complications.

Risk Factors for Surgical Site Infections After Lower Extremity Open Revascularization

BACKGROUND

Surgical site infection (SSI) is a serious complication of lower extremity open revascularization and is associated with increased morbidity, increased healthcare costs, and decreased postoperative quality of life. The objective of this study was to determine factors associated with an increased risk of developing postoperative SSI in patients undergoing lower extremity revascularization. Associations between SSI and postoperative complications were also identified.

METHODS

Patients who underwent lower extremity open revascularization from 2014-2017 were identified using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). A multivariate logistic regression analysis was used to determine risk factors associated with SSIs within 30 days of the operation and postoperative complications. Odds ratios (ORs) were adjusted for demographics, preoperative comorbidities, procedure type, and intraoperative variables.

RESULTS

Ten thousand nine hundred ten patients who underwent lower extremity open revascularization were identified, with a mean age of 67.24 years and of whom 7,318 (67%) were male. Of the 10,910 patients, 922 (8.45%) had an SSI within 30 days of the operation. Risk factors associated with developing SSI included body mass index 25-29.9 (OR, 1.34; 95% confidence interval [CI], 1.08-1.67), body mass index ≥ 30 (OR, 2.12; 95% CI, 1.71-2.62), history of severe chronic obstructive pulmonary disease (OR, 1.47; 95% CI, 1.18-1.84), preprocedural beta-blocker use (OR, 1.25; CI 95%, 1.05-1.49), procedure time > 214 minutes (OR, 1.44; 95% CI, 1.22-1.70), and creatinine > 1.2 (OR 1.03; 95% CI, 0.87-1.21). One factor associated with a decreased risk of developing SSI was male gender (OR, 0.71; 95% CI, 0.60-0.84). Patients who developed an SSI were more likely to have adverse outcomes such as myocardial infarction/stroke, major amputation, bleeding requiring transfusion or secondary procedure, or require a reintervention in the treated segment.

CONCLUSIONS

There are various patient-related and operative factors that increase the likelihood of developing an SSI after lower extremity open revascularization. These findings indicate that addressing modifiable perioperative SSI risk factors may be beneficial in decreasing rates of SSI and improving postoperative outcomes.

Artificial intelligence in atherosclerotic disease: Applications and trends

Atherosclerotic cardiovascular disease (ASCVD) is the most common cause of death globally. Increasing amounts of highly diverse ASCVD data are becoming available and artificial intelligence (AI) techniques now bear the promise of utilizing them to improve diagnosis, advance understanding of disease pathogenesis, enable outcome prediction, assist with clinical decision making and promote precision medicine approaches. Machine learning (ML) algorithms in particular, are already employed in cardiovascular imaging applications to facilitate automated disease detection and experts believe that ML will transform the field in the coming years. Current review first describes the key concepts of AI applications from a clinical standpoint. We then provide a focused overview of current AI applications in four main ASCVD domains: coronary artery disease (CAD), peripheral arterial disease (PAD), abdominal aortic aneurysm (AAA), and carotid artery disease. For each domain, applications are presented with refer to the primary imaging modality used [e.g., computed tomography (CT) or invasive angiography] and the key aim of the applied AI approaches, which include disease detection, phenotyping, outcome prediction, and assistance with clinical decision making. We conclude with the strengths and limitations of AI applications and provide future perspectives.

Surgical wound assessment tool: Construct validity and inter-rater reliability of a tool designed for nurses

AIMS AND OBJECTIVES

To validate construct validity and inter-rater reliability of a surgical wound assessment tool.

BACKGROUND

Wound assessment is central to appropriate wound management. However, limited standard surgical wound assessment tools are available to assist nurses in assessing and recording progress in the healing of surgical wounds.

DESIGN

A prospective observational study was utilised to test the validity and reliability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline was used.

METHODS

Convenience sampling was used to recruit 260 patients who underwent elective or emergency surgery at a hospital in Vietnam. Exploratory factor analysis was used to examine the construct validity of the surgical wound assessment tool. Inter-rater reliability was calculated using the intraclass correlation coefficient and Cohen's kappa to determine reliability of the overall scale and identified items.

RESULTS

The results of the exploratory factor analysis supported a three-component structure of the surgical wound assessment tool. The intraclass correlation coefficient value of the overall scale was 0.79 (95% CI 0.67-0.89), p < .001, confirming excellent inter-rater reliability. Cohen's kappa value ranged from 0.5 to 1, demonstrating moderate to almost perfect level of agreement for individual items, except for one item on pain.

CONCLUSION

The surgical wound assessment tool was deemed to be acceptable, valid and reliable for monitoring the status of surgical wound healing. However, further modification and testing are needed to strengthen the tool and to determine the applicability of the tool in other populations.

RELEVANCE TO CLINICAL PRACTICE

The application of the SWAT would improve the assessment of surgical wounds in daily nursing practice which will promote improved postoperative wound management. It is an easy and practical tool for enhancing inter-disciplinary communication and care outcomes for all patients with surgical wounds.

Single-center surgical site infection rate after peripheral ECMO decannulation and surgical repair

Objective:

Extracorporeal membrane oxygenation (ECMO) is used to provide heart–lung bypass support in cases of acute respiratory and cardiac failure. The two main classifications of ECMO are venoarterial (VA) and venovenous (VV). After the patient recovers from an acute state, ECMO decannulation from the groin often requires femoral exploration and vessel repair. This study was performed to quantify the rate of surgical site infection (SSI) after ECMO decannulation.

Methods:

Retrospective single-institutional review of patients requiring ECMO from January 2016 to October 2019 was conducted. The study examined incidence of SSI. We evaluated preoperative risk factors, VA versus VV ECMO, Szilagyi infection score, and postoperative management.

Results:

Initial search began with 176 ECMO cases, of which 106 patients were deceased before development of any infection. Eighteen were eliminated because of central ECMO access, and four were lost to chart privacy. Of the 154 patients requiring femoral ECMO, 48 (31%) survived, with 22 VA and 26 VV ECMO. Twelve patients were classified as infected, resulting in an overall SSI rate of 25%. Surgical repair of the femoral arterial cannulation site was required in the 22 VA ECMO patients, and 10 of these became infected, resulting in an infection rate of 45%. The remaining two infected were VV ECMO and did not require surgery. The VV ECMO SSI rate was 7.7%. The infected group of VA ECMO consisted of eight primary surgical repairs and two patch repairs. Eight of the patients required multiple reoperations and two required antibiotics and wound care alone. There was no instance of limb loss. Statistical analysis showed intraoperative transfusion of >250 ml and blood loss of >300 ml as the only predictive factors of infection. The Szilagyi score was found to be worse in patients requiring patch angioplasty.

Conclusion:

Surgical repair of ECMO arterial cannulation sites had postoperative SSIs in nearly half of the patients (45%). The VV ECMO SSI rate was found to be 7.7%. Severity of infection was worse in more complicated repairs. Overall ECMO mortality was high at 69%. Although we found no clear correlation with common risk factors, transfusions >250 ml and blood loss >300 ml were found to be predictive. Vascular surgeons should be aware of high risk of SSI with repair of femoral ECMO cannulation sites.

Obturator bypass remains a useful option

OBJECTIVES

The femoral tripod remains technically crucial in vascular surgery, as well for an elective revascularization as for an extensive approach to the arterial tree. The management of septic complications and healing disorders in this area is really challenging. Obturator bypass (OB) represents an alternative sometimes employed in this context, but few recent series were recently published. The objectives of this work were thus to evaluate the results of OB in terms of patency, morbi-mortality, healing evolution and absence of reinfection.

MATERIAL AND METHODS

This was a monocentric retrospective study including all the patients treated by OB, whatever the cause, between January 2010 and December 2020. Primary outcomes were the primary and the secondary patencies. The secondary outcomes were the morbi-mortality, freedom from infection and healing.

RESULTS

During this period, 23 OBs were carried out in 22 patients, with a majority of men (77%) whose median age was 70 years [34 - 87]. The indications were infection in 19 patients (86%), and iterative thrombosis in three patients (14%). The substitute was an arterial allograft in 82% of the cases, and the outflow was the deep femoral artery only in 14% of the cases. The median operative time was 224 min [111-391] and median blood losses were 900 mL [300-3900]. We observed seven systemic (32%), and eight local complications (36%). Healing was obtained in 90% of the cases, and freedom from infection was obtained in 100% of the cases. The median duration of follow-up was 594 days [5 - 2517]. One-year, two-year and three-year primary patency rates were 84%, 78%, and 63%, respectively. One-year, two-year and three-year secondary patencies were 94%, 94%, and 80%, respectively. One-month, one-year, two-year and three-year survival rates were 86%, 73%, 67%, and 53%, respectively.

CONCLUSION

Our study showed that the OB represents a relevant alternative in the event of complex lesions of the femoral tripod, with good patency and healing rates and good infection control. On the other hand, its consequences in terms of morbi-mortality confirm that OB is a major surgery that should be used when a traditional approach is not possible.

Groin Surgical Site Infection in Vascular Surgery: Systemic Review on Peri-Operative Antibiotic Prophylaxis

Objectives: Surgical site infections (SSIs) in lower extremity vascular surgeries, post-groin incision, are not only common complications and significant contributors to patient mortality and morbidity, but also major financial burdens on healthcare systems and patients. In spite of recent advances in pre- and post-operative care, SSI rates in the vascular surgery field remain significant. However, compliant antibiotic therapy can successfully reduce the SSI incidence pre- and post-surgery. Methods: In October 2021, we conducted a systematic literature review using OVID, PubMed, and EMBASE databases, centered on studies published between January 1980 and December 2020. The review adhered to the Preferred Reporting Items for Systematic Reviews and Meta Analyses checklist. Inclusion/exclusion criteria have been carefully selected and reported in the text. For analyses, we calculated 95% confidence intervals (CI) and weighted odds ratios to amalgamate control and study groups in publications. We applied The Cochrane Collaboration tool to assess bias risk in selected studies. Results: In total, 592 articles were identified. After the removal of duplicates and excluded studies, 36 full-texts were included for review. Conclusions: The review confirmed that antibiotic therapy, administered according to all peri-operative protocols described, is useful in reducing groin SSI rate in vascular surgery.

Meta-analysis of prophylactic closed-incision negative pressure wound therapy for vascular surgery groin wounds

OBJECTIVE

Previous meta-analysis of randomized control trials evaluating the efficacy of closed incision negative pressure wound therapy (ciNPWT) on vascular surgery groin wounds reported a reduction in surgical site infections (SSI). Our aim was to perform a comprehensive, updated meta-analysis after the largest multicenter randomized control trial (RCT) on the subject to date reported no benefit of ciNPWT.

METHODS

A systematic review identified RCTs that compared the primary outcome of incidence of postoperative SSIs of groin incisions treated with ciNPWT or standard dressings. Secondary outcomes included wound dehiscence, composite incidence of seroma / lymph leak / hematoma, need for reoperation, in-hospital mortality, need for readmission and hospital length of stay. Odds ratios were compared across studies using random effects meta-analysis. Risk of bias was assessed using the Cochrane Risk of Bias tool, Harbord test and trim-and-fill analysis.

RESULTS

Eight RCTs comprised of 1125 incisions (n = 555 [49.3%] ciNPT, n = 570 [50.7%] control) were included. RCTs included 3 studies inside and 5 outside of the United States. ciNPWT was associated with a significant reduction in rate of SSIs (OR 0.39; 95% CI 0.24-0.63; p < 0.001). There was no significant difference in rate of wound dehiscence (OR 1.11, 95% CI 0.67-1.83, p = 0.68), composite incidence of seroma, lymph leak or hematoma (OR 0.49, 95% CI 0.13-1.76, p= 0.27), need for reoperation (OR 0.68, 95% CI 0.40-1.16, p = 0.16), or need for readmission (OR 0.60, 95% CI 0.30-1.21, p = 0.15). It was not possible to quantitatively evaluate in-hospital mortality or hospital length of stay. Risk of bias assessment identified high risk of bias regarding participant blinding in all studies, low risk in randomization and outcome reporting, and variability between studies in other methodologies. There was no evidence of publication bias.

CONCLUSIONS

Meta-analysis of pooled data suggest prophylactic use of ciNPWT for vascular groin incisions is associated with reduced rates of SSIs, with the greatest benefits seen in trials with higher baseline rates of infection in the control group.

Comparison of transverse versus longitudinal skin incisions for femoral endarterectomy and patchplasty

INTRODUCTION

Access to the femoral artery for a femoral endarterectomy and patchplasty (CFE) can be undertaken either through transverse (TI) or longitudinal incision (LI). LIs have been shown in previous studies to have higher groin complications though these were undertaken in multiple types of vascular procedures. We looked at wound complications for patients undergoing elective CFE procedures only with or without angioplasty via TI or LI.

METHODS

All patients who had undergone CFE were retrospectively analysed from a prospective database. Length of stay, wound complications and readmission rates were recorded. Factors for wound complication were looked at using logistic regression with backward elimination.

RESULTS

122 CFE procedures were performed (30 TI) over the study period. 92 (76.7%) of patients had a prosthetic patch used, whilst 57 (46.7%) patients underwent an adjunctive endovascular procedure, namely, iliac angioplasty and stenting. Median length of stay was 3 days for both groups. The wound complication rate was 6.7% in the TI group and 22.6% in the LI group. 85.6% of the wound complications were identified after discharge. 6/122 (4.9%) were readmitted for intravenous antibiotics, whilst others were managed in the outpatient setting. TI (aOR = 0.15; 95% 0.03-0.75) and combined open FE with endovascular revascularisation (aOR = 0.33; 95% 0.11-0.95) had protective effects on wound complications. Type of the patch used was not associated with any wound complications (p = 0.07).

CONCLUSION

Compared to traditional LI, TI for CFE and OTA have lower risk of wound complications and reduced readmission rates in our series. We advocate adopting TI as the standard for femoral artery procedures rather than LI.

Current applications of artificial intelligence in vascular surgery

Basic foundations of artificial intelligence (AI) include analyzing large amounts of data, recognizing patterns, and predicting outcomes. At the core of AI are well-defined areas, such as machine learning, natural language processing, artificial neural networks, and computer vision. Although research and development of AI in health care is being conducted in many medical subspecialties, only a few applications have been implemented in clinical practice. This is true in vascular surgery, where applications are mostly in the translational research stage. These AI applications are being evaluated in the realms of vascular diagnostics, perioperative medicine, risk stratification, and outcome prediction, among others. Apart from the technical challenges of AI and research outcomes on safe and beneficial use in patient care, ethical issues and policy surrounding AI will present future challenges for its successful implementation. This review will give a brief overview and a basic understanding of AI and summarize the currently available and used clinical AI applications in vascular surgery.

Gentamicin-Containing Collagen Implant May Reduce Surgical Site Infections After Open Infrainguinal Arterial Revascularization

BACKGROUND

Deep-space surgical site infections carry significant morbidity and mortality. The evidence for gentamicin-containing collagen implants at reducing surgical site infections in open infrainguinal arterial surgery is limited. This study examined whether gentamicin-containing collagen implants reduces 30-day surgical site infections and their severity following open infrainguinal arterial surgery.

METHODS

A retrospective observational cohort study that included all patients undergoing infrainguinal arterial bypass or endarterectomy between November 2015 and March 2019 at a single tertiary vascular unit. Patients with contaminated/infected surgical fields, surgical wounds treated with negative pressure therapy, or the usage of antimicrobial implants and dressings other than Collatamp G^Ⓡ (Aralez Pharmaceuticals, Canada) were excluded. Patients with gentamicin-containing collagen implants placed abutting vasculature were compared against patients without gentamicin-containing collagen implants. Outcomes included the rate of surgical site infections and their severity within 30 days after the operation.

RESULTS

In 159 procedures (mean age 67.7 years, 74.8% male, 33.3% diabetic, 16.4% chronic renal failure, 25.2% anticoagulated postoperatively, 32.7% with prosthetic implants), 55 (34.6%) procedures received gentamicin-containing collagen implants. There were significantly more males (85.5% vs. 69.2%; P = 0.025), higher rates of obesity (41.8% vs. 26.0%; P = 0.041), and hyperlipidemia (65.5% vs. 49.0%; P = 0.048) in the gentamicin-containing collagen implant group. In total, 6 (3.8%) procedures developed deep-space surgical site infections (1 with gentamicin-containing collagen implant, 5 without) and 13 (8.2%) had severe surgical site infections that required re-intervention (1 with gentamicin-containing collagen implant, 12 without). On logistic regression analysis, the absence of gentamicin-containing collagen implants statistically significantly increased the odds of overall surgical site infections (OR = 2.50; 95% CI 1.01 - 6.19; P = 0.047). There was no statistically significant difference in the odds of deep-space surgical site infections or the severity and need for reintervention of surgical site infections.

CONCLUSIONS

This is the first study that examined the effect of gentamicin-containing collagen implants on the severity of surgical site infections in vascular surgery. Gentamicin-containing collagen implants may reduce the odds of overall surgical site infections. It did not reduce the odds of deep-space surgical site infections or the severity and reintervention rate of surgical site infections following infrainguinal arterial revascularization. Larger studies are required to achieve adequate power to assess for these outcomes.

Leveraging Machine Learning and Artificial Intelligence to Improve Peripheral Artery Disease Detection, Treatment, and Outcomes

Peripheral artery disease is an atherosclerotic disorder which, when present, portends poor patient outcomes. Low diagnosis rates perpetuate poor management, leading to limb loss and excess rates of cardiovascular morbidity and death. Machine learning algorithms and artificially intelligent systems have shown great promise in application to many areas in health care, such as accurately detecting disease, predicting patient outcomes, and automating image interpretation. Although the application of these technologies to peripheral artery disease are in their infancy, their promises are tremendous. In this review, we provide an introduction to important concepts in the fields of machine learning and artificial intelligence, detail the current state of how these technologies have been applied to peripheral artery disease, and discuss potential areas for future care enhancement with advanced analytics.

A nationwide assessment of the burden of healthcare-associated infections and antimicrobial use among surgical patients: results from Serbian point prevalence survey, 2017

BACKGROUND

As the only non-European Union (EU) country, Serbia participated in a second point prevalence survey of healthcare-associated infections (HAIs) and antimicrobial use (AMU) organized by the European Centre for Disease Prevention and Control (ECDC) in the EU countries. Here, we aimed to estimate the prevalence of HAI and AMU in patients who had recently undergone a surgery and to compare risk profile, HAI rates, and AMU among surgical patients and non-surgical patients.

METHODS

A national PPS was performed in 65 Serbian acute-care hospitals, in November 2017. In this paper, the data of 61 hospitals for adult acute-care were analyzed. To ensure the comparability of study design we used the Serbian translation of ECDC case definitions and ECDC PPS protocol. The trained infection control staff, led by a hospital coordinator, reviewed medical records to identify HAI active at the time of the survey and AMU. Only inpatients admitted to the ward before 8 a.m. on the day if the survey were included.

RESULTS

A total of 12,478 patients from 61 hospitals for adult acute-care were eligible for inclusion in this study. Significantly higher proportions of surgical patients were female, belonged to the 60-to-79 age group, and were less severely ill. Also, extrinsic factors (invasive devices, hospitalization at the ICU, and prior antibiotics therapy) were more frequent in surgical patients. Prevalence of HAIs was higher among surgical patients (261/3626; 7.2%) than among non-surgical patients (258/8852; 2.9%) (p < 0.0001). The highest prevalence of all HAIs was noted in patients who had kidney transplantation (4/11; 36.4%), while SSIs were the most prevalent among patients who had peripheral vascular bypass surgery (3/15; 20.0%). Non-surgical patients received treatment for community-acquired infections in significantly higher proportion (2664/8852; 64.3) (p < 0.001). Surgical prophylaxis for more than 1 day was applied in 71.4% of surgical patients.

CONCLUSION

We have provided an insight into the burden of HAIs and AMU among Serbia acute-care hospitals, and highlighted several priority areas and targets for quality improvement.

A multicenter, prospective randomized trial of negative pressure wound therapy for infrainguinal revascularization with a groin incision

BACKGROUND

Wound complications after open infrainguinal revascularization are a frequent cause of patient morbidity, resulting in increased healthcare costs. The purpose of the present study was to assess the effects of closed incision negative pressure therapy (ciNPT) on groin wound complications after infrainguinal bypass and femoral endarterectomy.

METHODS

A total of 242 patients who had undergone infrainguinal bypass (n = 124) or femoral endarterectomy (n = 118) at five academic medical centers in New England from April 2015 to August 2019 were randomized to ciNPT (PREVENA; 3M KCI, St Paul, Minn; n = 118) or standard gauze (n = 124). The primary outcome measure was a composite endpoint of groin wound complications, including surgical site infections (SSIs), major noninfectious wound complications, or graft infections within 30 days after surgery. The secondary outcome measures included 30-day SSIs, 30-day noninfectious wound complications, readmission for wound complications, significant adverse events, and health-related quality of life using the EuroQoL 5D-3L survey.

RESULTS

The ciNPT and control groups had similar demographics (age, 67 vs 67 years, P = .98; male gender, 71% vs 70%, P = .86; white race, 93% vs 93%, P = .97), comorbidities (previous or current smoking, 93% vs 94%, P = .46; diabetes, 41% vs 48%, P = .20; renal insufficiency, 4% vs 7%, P = .31), and operative characteristics, including procedure type, autogenous conduit, and operative time. No differences were found in the primary composite outcome at 30 days between the two groups (ciNPT vs control: 31% vs 28%; P = .55). The incidence of SSI at 30 days was similar between the two groups (ciNPT vs control: 11% vs 12%; P = .58). Infectious (13.9% vs 12.6%; P = .77) and noninfectious (20.9% vs 17.6%; P = .53) wound complications at 30 days were also similar for the ciNPT and control groups. Wound complications requiring readmission also similar between the two groups (ciNPT vs control: 9% vs 7%; P = .54). The significant adverse event rates were not different between the two groups (ciNPT vs control: 13% vs 16%; P = .53). The mean length of the initial hospitalization was the same for the ciNPT and control groups (5.2 vs 5.7 days; P = .63). The overall health-related quality of life was similar at baseline and at 14 and 30 days postoperatively for the two groups. Although not powered for stratification, we found no differences among the subgroups in gender, obesity, diabetes, smoking, claudication, chronic limb threatening ischemia, bypass, or endarterectomy. On multivariable analysis, no differences were found in wound complications at 30 days for the ciNPT vs gauze groups (odds ratio, 1.4; 95% confidence interval, 0.8-2.6; P = .234).

CONCLUSIONS

In contrast to other randomized studies, our multicenter trial of infrainguinal revascularization found no differences in the 30-day groin wound complications for patients treated with ciNPT vs standard gauze dressings. However, the SSI rate was lower in the control group than reported in other studies, suggesting other practice patterns and processes of care might have reduced the rate of groin infections. Further study might identify the subsets of high-risk patients that could benefit from ciNPT.

Society for Vascular Surgery femoral runoff score is associated with limb-based patency after aortofemoral bypass

OBJECTIVE

Despite advancements, aortofemoral bypass (AFB) remains the most durable option for aortoiliac occlusive disease. Although runoff has been shown to be associated with AFB patency, the association of the Society for Vascular Surgery (SVS) thigh runoff scoring system with patency has not been assessed. The aim of the present study was to evaluate the association between the SVS runoff scoring system and limb-based primary patency after AFB.

METHODS

Institutional data for patients undergoing AFB with preoperative runoff imaging available from 2000 to 2017 were queried. Runoff scores were assigned according to the presence of occlusive disease in the superficial femoral artery and profunda femoris artery (minimum, 1; maximum, 10) as described by the 1997 SVS reporting standards for lower extremity ischemia. Limb-based patency was the primary endpoint. Kaplan-Meier analysis was used to compare the long-term limb-based patency and freedom from reintervention between limbs with runoff scores ≥6 and those with runoff scores <6. Propensity score-weighted Cox proportional hazards modeling was used to evaluate the association between a runoff score of ≥6 and primary patency loss, controlling for other factors associated with primary patency.

RESULTS

In 161 patients, 316 limbs had undergone revascularization. The mean patient age was 66.7 ± 11.3 years, and 51.6% were women. Most limbs had undergone revascularization for claudication (56.5%). Most (89.4%) had TransAtlantic InterSociety Consensus class D lesions, 27.3% had required suprarenal or higher clamping, and 11.2% had undergone concomitant mesenteric intervention. A femoral outflow adjunct and concurrent lower extremity bypass was required in 41.8% and 2.9% of limbs, respectively. Those with a runoff score of ≥6 had experienced greater rates of 30-day myocardial infarction (11% vs 1%; P = .005), respiratory failure (11% vs 1%; P = .005), and mortality (8% vs 0%; P ≤ .006). The median follow-up period was 4.0 years (interquartile range, 6.5 years). The 1-, 3-, and 5-year primary patency was 94.6% (95% confidence interval [CI], 91.9%-97.3%), 89.2% (95% CI, 85.4%-93.2%), and 81.4% (95% CI, 76.0%-87.1%), respectively. The 5-year primary-assisted patency, secondary patency, and freedom from reintervention were 84.9% (95% CI, 79.7%-90.5%), 91.7% (95% CI, 87.3%-96.3%), and 83.3% (95% CI, 78.3%-88.7%), respectively. Patients with a runoff score of ≥6 had lower primary (log-rank P < .01), primary-assisted (P < .01), and secondary patency (P = .01). The factors associated with the loss of primary patency included a high runoff score (runoff score of ≥6: hazard ratio [HR], 4.1; 95% CI, 2.1-8.0; P < .01), simultaneous mesenteric endarterectomy (HR, 13.5; 95% CI, 1.9-97.8; P = .01), and chronic kidney disease (HR, 4.6; 95% CI, 1.5-14.6; P = .01). Increasing age (HR, 0.94 per year; 95% CI, 0.91-0.97; P < .01) and hyperlipidemia (HR, 0.44; 95% CI, 0.23-0.85; P = .01) were protective.

CONCLUSIONS

The SVS femoral runoff score is an important factor associated with long-term AFB limb patency. Scores of ≥6 portend for worse limb outcomes and a greater incidence of operative complications. The SVS score can be determined from preoperative axial imaging studies and serve as a guide in decision-making and operative planning.

Longitudinal versus transverse incision for common femoral artery exposure: a systematic review and meta-analysis

BACKGROUND

A longitudinal or a transverse incision is routinely used for common femoral artery (CFA) exposure. Some believe a transverse incision is associated with a lower incidence of postoperative complications. We performed a systematic review and meta-analysis to evaluate the risk of postoperative surgical site infection, lymphatic complications, wound dehiscence and haematoma formation when using a longitudinal or transverse incision for CFA exposure.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were adhered to. We searched various databases such as MEDLINE via PubMed and Embase for relevant studies from inception till 31 May 2020. Relevant search terms such as 'longitudinal', 'transverse', 'vertical', 'horizontal', 'femoral', 'incision' were used. We included both randomized controlled trials and case-controlled studies, and extracted data related to study characteristics and postoperative complications. We assessed risk of bias using the Cochrane risk of bias tool and the Newcastle-Ottawa scale. A random-effects meta-analysis was performed to obtain the pooled proportions and risk ratios (RR) for our study outcomes.

RESULTS

We included seven studies with a total of 5922 groin incisions. A longitudinal incision was associated with a significantly higher incidence of wound infection (RR 2.93, 95% confidence interval (CI) 1.12-7.70, P = 0.03) and wound dehiscence (RR 2.87, 95% CI 1.06-7.77, P = 0.04). The risk of lymphatic complications (RR 1.09, 95% CI 0.39-3.05, P = 0.87) and wound haematoma (RR 2.85, 95% CI 0.88-9.21, P = 0.08) were similar.

CONCLUSIONS

A longitudinal incision may be associated with a higher incidence of wound infection and wound dehiscence, as compared to using a transverse incision for CFA exposure.

Contemporary Review to Reduce Groin Surgical Site Infections in Vascular Surgery

Surgical site infection (SSIs) in lower extremity vascular procedures is a major contributor to patient morbidity and mortality. Despite previous advancements in preoperative and postoperative care, the surgical infection rate in vascular surgery remains high, particularly when groin incisions are involved. However, successfully targeting modifiable risk factors reduces the surgical site infection incidence in vascular surgery patients. We conducted an extensive literature review to evaluate the efficacy of various preventive strategies for groin surgical site infections. We discuss the role of preoperative showers, preoperative and postoperative antibiotics, collagen gentamicin implants, iodine impregnated drapes, types of skin incisions, negative pressure wound therapy, and prophylactic muscle flap transposition in preventing surgical site infection in the groin after vascular surgical procedures.

Tension-Free Management of Surgical Wound in Paramalleolar Bypass

Objective: In paramalleolar bypass for critical limb-threatening ischemia (CLTI), excessive skin tension may occur for the closure of surgical wounds around the ankle. Furthermore, these surgical incisions are often proximal to infectious ischemic ulcers. Wound dehiscence caused by skin tension and surgical site infection carries a risk of graft exposure, anastomotic disruption, or graft insufficiency. Patients and Methods: Tension-free wound management was adopted in eight patients who underwent paramalleolar bypass for CLTI. Tension-free closure was adopted for surgical incisions for distal anastomotic site of the paramalleolar bypass, whereas the incisions for saphenous vein harvest were left open. A relief incision was made as needed. The opened incisions were covered with artificial dermis. Results: All surgical incisions and ischemic wounds healed successfully within 1.8 months after bypass. Two postoperative graft stenoses occurred, which were rescued by additional endovascular intervention. Secondary graft patency, wound healing, and limb salvage rates were 100% during an average follow-up period of 30 months. Conclusion: Tension-free wound closure using artificial dermis was effective in selected cases of paramalleolar bypass for CLTI.

The association between preoperative length of stay and surgical site infection after lower extremity bypass for chronic limb-threatening ischemia

OBJECTIVE

Surgical site infection (SSI) is an important complication of lower extremity bypass (LEB) and the rate of SSI after LEB varies widely in the existing literature, ranging from 4% to 31%. Prolonged length of stay (LOS) has been implicated in the occurrence of SSI across multiple surgical disciplines. The impact of preoperative LOS in patients with chronic limb-threatening ischemia (CLTI) undergoing LEB is unknown. We examined the association of preoperative LOS on SSI after LEB.

METHODS

A retrospective analysis of the Society for Vascular Surgery Vascular Quality Initiative Infrainguinal Bypass Registry identified patients undergoing elective LEB for chronic limb-threatening ischemia from 2003 to 2019. Patients undergoing LEB for acute limb ischemia, urgent/emergent procedures, aneurysm, or who had concomitant suprainguinal bypass were excluded. The primary outcome measure was postoperative SSI. Multivariable forward stepwise logistic regression was then performed including all variables with a P value of less than .10 in both matched and unmatched cohorts to evaluate for demographic and perioperative predictors of SSI. Propensity score matching was used to create matched cohorts of patients for each LOS group.

RESULTS

A total of 17,883 LEB procedures were selected for inclusion: 0 days (12,362 LEB), 1 to 2 days (1737 LEB), and 3 to 14 days (3784 LEB). Patients with the greatest preoperative LOS were more likely to have vein mapping (0 days preoperative LOS, 66.3%; 1-2 days, 65.2%; 3-14 days, 73.2%; P < .01) or computed tomography angiography/magnetic resonance angiography (0 days, 32.1%; 1-2 days, 34.4%; 3-14 days, 38.4%; P < .01). Patients with 3 or more days of preoperative LOS had longer procedure lengths (0 days, 244 minutes; 1-2 days, 243 minutes; 3-14 days, 255 minutes; P < .01) and were more likely to have completion angiogram (0 days, 27.1%; 1-2 days, 29.5%; 3-14 days, 31.6%; P = .02). Multivariable logistic regression demonstrated that preoperative LOS of 3 to 14 days was associated with increased rate of SSI (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.20-3.07; P = .01). Transfusion of 3 or more units (OR, 2.87; 95% CI, 1.89-4.36; P < .01) and prolonged procedure length (>220 minutes; OR, 1.86; 95% CI, 1.26-2.73; P < .01) were also significantly associated with postoperative SSIs.

CONCLUSIONS

Many factors including preoperative comorbidities and operative complexity covary with preoperative LOS as risk factors for SSI. However, when patients are matched based on comorbidities and factors that would predict overall clinical complexity, preoperative LOS remains important in predicting SSI.

One Health in hospitals: how understanding the dynamics of people, animals, and the hospital built-environment can be used to better inform interventions for antimicrobial-resistant gram-positive infections

Despite improvements in hospital infection prevention and control, healthcare associated infections (HAIs) remain a challenge with significant patient morbidity, mortality, and cost for the healthcare system. In this review, we use a One Health framework (human, animal, and environmental health) to explain the epidemiology, demonstrate key knowledge gaps in infection prevention policy, and explore improvements to control Gram-positive pathogens in the healthcare environment. We discuss patient and healthcare worker interactions with the hospital environment that can lead to transmission of the most common Gram-positive hospital pathogens – methicillin-resistant Staphylococcus aureus, Clostridioides (Clostridium) difficile, and vancomycin-resistant Enterococcus – and detail interventions that target these two One Health domains. We discuss the role of animals in the healthcare settings, knowledge gaps regarding their role in pathogen transmission, and the absence of infection risk mitigation strategies targeting animals. We advocate for novel infection prevention and control programs, founded on the pillars of One Health, to reduce Gram-positive hospital-associated pathogen transmission.

Four Curious Cases of Closed-Incision Negative Pressure Therapy (ciNPT)

Post-operative wound complications after infrainguinal vascular surgery can lead to a significant decrease in a patient’s quality of life. The main complications are surgical site infection, wound dehiscence, seroma, hematoma, delayed healing and/or poor scarring. Closed-incision negative pressure therapy (ciNPT) in particular has recently been suggested as a method of prophylaxis against these surgical site complications when applied over a closed wound. In our unit, it has generally been used for long groin and abdominal surgical wounds.

We describe here four relatively unusual cases of our experience using ciNPT. In our series, ciNPT has been used to good effect on small eccentrically shaped wounds and non-resolving groin hematomas. We have also used it in tandem with intra-cavity Vacuum Assisted Closure (VAC) (KCI, Acelity, San Antonio, TX) dressings for the management of partially closed wounds to reduce risk of infection and dehiscence. Additionally, it has shown good analgesic effects in our patient post-operatively.

Hence, we suggest that the paradigm of ciNPT can be expanded to include these circumstances to improve wound healing and decrease risk of post-operative complications. Further research into the overall clinical benefits and cost-effectiveness will also be helpful.

Bloodstream infections and patient survival with tunneled-cuffed catheters for hemodialysis: A single-center observational study

BACKGROUND

In hemodialysis patients, a tunneled-cuffed permanent catheter is mandatory when the arteriovenous fistula is not feasible. The major risks of the use of tunneled-cuffed permanent catheter are bloodstream infections. The aim of this study is to analyze bloodstream infections from tunneled-cuffed permanent catheter in hemodialysis patients.

METHODS

An observational prospective study was carried out and 79 hemodialysis patients with tunneled-cuffed permanent catheter were enrolled. Patients were divided into those with bloodstream infections from tunneled-cuffed permanent catheter and those without. Their clinical and laboratory characteristics were compared. An original tunneled-cuffed permanent catheter lock therapy sequence was carried out combined with systemic antibiotic therapy. In case of antibiotic resistance, the tunneled-cuffed permanent catheter was removed.

RESULTS

The patients affected by bloodstream infections from tunneled-cuffed permanent catheter were 16/79 (20.3%). The bloodstream infection from tunneled-cuffed permanent catheter's incidence rate was 0.52 per 1000 catheter days. Twenty-three bloodstream infections from tunneled-cuffed permanent catheter were found in 16/79 patients who used tunneled-cuffed permanent catheter. Staphylococcus aureus was the cause of bloodstream infection from tunneled-cuffed permanent catheter in 35% of the cases and Staphylococcus epidermidis in 30% of the cases. Risk factors were infection located in other organs and the presence of peripheral obstructive arterial disease.

CONCLUSION

The enrolled cohort showed a reduced bloodstream infection from tunneled-cuffed permanent catheter incidence rate in comparison with the reference value (1 per 1000 catheter days). To reduce the number of bloodstream infections from tunneled-cuffed permanent catheter, hand hygiene and asepsis management of the tunneled-cuffed permanent catheter during the connection to the extracorporeal circuit and an original tunneled-cuffed permanent catheter lock therapy sequence seem to be the most efficient measures. Infections of other organs and the presence of peripheral obstructive arterial disease are the most important risk factors for bloodstream infections from tunneled-cuffed permanent catheter.

A Scoping Review on the Use of Antibiotic-Impregnated Beads and Applications to Vascular Surgery

INTRODUCTION

Surgical site infection (SSI) presents a ubiquitous concern to surgical specialties, especially in the presence of prosthetic material. Antibiotic-impregnated beads present a novel and evolving means to combat this condition. This review aims to analyze the quality of evidence and methods of antibiotic bead use, particularly for application within vascular surgery.

METHODS

A systematic scoping review was conducted within Embase, MEDLINE, and the Cochrane Registry of Randomized Controlled Trials. Articles were evaluated by 2 independent reviewers. Level of evidence was evaluated using the Oxford Center for Evidence-Based Medicine Criteria and the Cochrane Risk of Bias Tool for Randomized Controlled Trials.

RESULTS

The search yielded 6951 papers, with 275 included for final analysis. Publications increased in frequency from 1978 to the present. The most common formulation was polymethyl methacrylate; however publications on biodegradable formulations, including calcium sulfate beads, have been published with increasing frequency. Most publications had positive conclusions (94.2%); however, the data was mainly subjective and may be prone to publication bias. Only 11 randomized controlled trials were identified and all but one was evaluated to be at a high risk of bias. The most common indication was for osteomyelitis (52%), orthopedic prosthetic infections (20%), and trauma (9%). Within vascular surgery, beads have been used primarily for the treatment of graft infection, with freedom from recurrence rates being reported from 41% to 87.5%.

CONCLUSIONS

Antibiotic-impregnated beads provide a means to deliver high doses of antibiotic directly to a surgical site, without the risks of parenteral therapy. There has yet to be significant high-level quality data published on their use. There is a large body of evidence that suggests antibiotic beads may be used in SSIs in high-risk patients, prosthetic infections, and other complex surgical infections. Important potential areas of application in vascular surgery include graft infection, prevention of wound infection in high-risk patients, and diabetic foot infection.

Dermabond and Tegaderm: A Better Surgical Incision Dressing

Surgical site infections (SSIs) are a common source of morbidity with vascular surgery incisions, especially in the groin. Single institution case series have widely varying, but high incidences of groin wound infection after open lower extremity revascularization. Optimally, a dressing that did not require changes, had low cost, and was water resistant would be optimal in these patients. We developed and validate a new dressing utilizing Dermabond (Ethibond™) and Tegaderm™ for vascular surgery incisions that could simplify and reduce postoperative SSIs. In this initial experience, we reviewed 94 patients. Of the 94 patients, 0 had signs of infection superficial or deep, dehiscence, or evidence of nonhealing. Gluing a Tegaderm to an incision using Dermabond is a novel and easy way to perform dressing that reduces wound infection, increases patient comfort, avoids dressing changes, and allows visualization of the wound.

Factors Associated with Wound Complications after Open Femoral Artery Exposure for Elective Endovascular Abdominal Aortic Aneurysm Repair

We identified factors that would lead to wound complications after open femoral exposure for endovascular abdominal aortic aneurysm repair (oEVAR). Using the National Surgical Quality Improvement Program dataset (2005-2014), we examined the patients who underwent oEVAR. Patients were stratified on whether they developed postoperative wound complications. Comparisons were made between group with wound complications and those without and adjusted analyses performed to identify variables that independently increased the risk of wound complications. There were 14,868 patients in the study cohort and 2.6% (384 patients) developed wound complications after EVAR. Among those with wound complications, 94% (360 patients) of patients had superficial and deep surgical site infection. Patients who had wound complication were likely to be younger (72.6 vs. 73.7 years old ( p  = 0.02), functionally dependent (5.4 vs. 2.5%) ( p  < 0.05), smoker (3 vs. 2.4%, p =0.03), female (4 vs. 2.2%), with significantly higher body mass index (31 vs. 28), and more commonly had diabetes (4 vs. 2.4%, p  < 0.001) or renal failure (12 vs. 3%, p  < 0.001). Although perioperative survival was similar, patients who had wound complications had significantly longer hospital length of stay (LOS) (7.3 ± 12 vs. 3.4 ± 5 days, p  < 0.001). Up to 3% patients developed wound complications after open femoral exposure during EVAR with significantly higher LOS and therefore cost utilization.

Comparison of open and endovascular procedures in patients with critical limb ischemia on dialysis

OBJECTIVE

Peripheral artery disease is a common comorbidity in patients with end-stage renal disease (ESRD), but there is a paucity of data comparing outcomes of different interventions in this group of patients. In this study, we examined perioperative outcomes of lower extremity endovascular revascularization (ER) and open revascularization (OR) in dialysis patients with critical limb ischemia (CLI).

METHODS

Patients on dialysis and undergoing ER and OR for CLI from 2011 to 2015 were identified in the American College of Surgeons National Surgical Quality Improvement Program dataset. Patient demographics, comorbidities, anatomic features, and perioperative outcomes were compared between ER and OR procedures.

RESULTS

From 2011 to 2015, 1021 lower extremity revascularizations were performed in dialysis patients with CLI. In this group, 535 were ER (53%) and 486 were OR (47%) procedures. Although demographic characteristics such as age and gender were similar between the two groups, there was a higher proportion of Caucasians and African Americans in the OR group. Patients undergoing open and endovascular procedures had similar rates of hypertension, congestive heart failure, diabetes, chronic obstructive pulmonary disease, and bleeding disorders. A minority of procedures (4%) were emergencies, which were distributed equally between the two groups. Preoperative aspirin usage was higher in the ER group (84% vs 78%; P = .024), beta-blocker use was higher in the OR group (79% vs 74%; P = .08), and statin use was similar between the two groups (72% in OR and 70% in ER; P = .54). On risk-adjusted multivariate analysis, OR was associated with a lower rate of major amputation (5.97% vs 11.78%; odds ratio, 0.48; 95% confidence interval [CI], 0.26-0.85), but a higher rate of postoperative bleeding (29.6% vs 8.97%; odds ratio, 2.86; 95% CI, 1.8-4.35) and wound complications (15% vs 3%; odds ratio, 4.5; 95% CI, 2.38-8.3). The 30-day mortality and cardiovascular morbidity were similar between the two groups.

CONCLUSIONS

In patients with ESRD with CLI, OR is associated with a lower risk of major limb amputation but a higher rate of postoperative wound complications and bleeding, compared with ER. Cardiovascular complications, 30-day mortality, reinterventions and readmissions were similar between the two groups. In patients with ESRD with CLI, OR should be considered as an option for limb salvage if feasible. Long-term outcomes comparing the two types of procedures are needed.