Perioperative Outcomes of Lower Extremity Revascularization for Rest Pain and Tissue Loss

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.

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.

Daly/Cost comparison in the management of peripheral arterial disease at 17 Belgian hospitals

OBJECTIVE

Peripheral arterial disease (PAD) is a manifestation of atherosclerosis that affects the lower extremities and afflicts more than 200 million people worldwide. Because of limited resources, the need to provide quality care associated with cost control is essential for health policies. Our study concerns an interhospital comparison among seventeen Belgian hospitals that integrates the weighting of quality indicators and the costs of care, from the hospital perspective, for a patient with this pathology in 2018.

METHODS

The disability-adjusted life years (DALYs) were calculated by adding the number of years of life lost due to premature death and the number of years of life lost due to disability for each in-hospital stay. The DALY impact was interpreted according to patient safety indicators. We compared the hospitals using the adjusted values ​​of costs and DALYs for their case mix index, obtained by relating the observed value to the predicted value obtained by linear regression.

RESULTS

We studied 2,437 patients and recorded a total of 560.1 DALYs in hospitals. The in-hospital cost average [standard deviation (SD)] was €8,673 (€10,893). Our model identified the hospitals whose observed values were higher than predicted; six needed to reduce the costs and impacts of DALYs, six needed to improve one of the two factors, and four seemed to have good results. The average cost (SD) for the worst performing hospitals amounted to €27,803 (€28,358).

CONCLUSIONS

Studying the costs of treatment according to patient safety indicators permits us to evaluate the entire chain of care using a comparable unit of measurement.

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.

A Systematic Review and Meta-Analysis on Sex-Based Disparities in Patients with Chronic Limb Threatening Ischemia Undergoing Revascularization

BACKGROUND

This systematic review and meta-analysis sought to describe the prognostic implications of sex on the clinical outcomes of patients undergoing interventions for chronic limb threatening ischemia (CLTI).

METHODS

Studies were systematically searched across 7 databases from inception to August 25, 2021 and rerun on October 11, 2022. Studies focusing on patients with CLTI undergoing open surgery, endovascular treatment (EVT), or hybrid procedures were included if sex-based differences were associated with a clinical outcome. Two independent reviewers screened studies for inclusion, extracted data, and assessed risk of bias using the Newcastle-Ottawa scale. Primary outcomes included inpatient mortality, major adverse limb events (MALE), and amputation-free survival (AFS). Meta-analyses were performed using random effects models and reported pooled odds ratio (pOR) and 95% confidence interval (CI).

RESULTS

A total of 57 studies were included in the analysis. A meta-analysis of 6 studies demonstrated that female sex was associated with statistically higher inpatient mortality compared to male sex undergoing open surgery or EVT (pOR, 1.17; 95% CI: 1.11-1.23). Female sex also demonstrated a trend toward increased limb loss in those undergoing EVT (pOR, 1.15; 95% CI: 0.91-1.45) and open surgery (pOR 1.46; 95% CI: 0.84-2.55). Female sex also had a trend toward higher MALE (pOR, 1.06; 95% CI, 0.92-1.21) in 6 studies. Finally, female sex had a trend toward worse AFS (pOR, 0.85; 95% CI, 0.70-1.03) in 8 studies.

CONCLUSIONS

Female sex was significantly associated with higher inpatient mortality and a trend toward higher MALE following revascularization. Female sex trended toward worse AFS. The reasons for these disparities are likely multifaceted on patient, provider, and systemic levels and should be explored to identify solutions for decreasing these health inequities across this vulnerable patient population.

Prognostic impact of atrial fibrillation on the outcomes of peripheral artery disease according to preoperative symptoms for endovascular revascularization

Peripheral artery disease (PAD) and atrial fibrillation (AF) are associated with major cardiovascular and cerebrovascular events (MACCE). However, outcomes stratified according to the preoperative symptoms of PAD in patients with AF have not been sufficiently investigated. This was a retrospective study of prospectively collected data pertaining to 2237 patients (1179 patients with intermittent claudication [IC] and 1058 patients with critical limb-threatening ischemia [CLTI]) who underwent endovascular therapy at 34 hospitals between August 2014 and August 2016. AF was present in 91 (7.7%) patients with IC and 150 (14.2%) patients with CLTI. In the CLTI group, patients with AF had a higher event rate of MACCE and all-cause death than those without AF (1-year rates of freedom from MACCE: 0.66 and 0.81 in patients with and without AF, respectively, p < 0.001). In contrast, in the IC group, there was no statistically significant difference in the rates of MACCE between patients with and without AF. In the Cox multivariate analysis, AF was a significant predictor of MACCE in patients with CLTI but not in patients with IC, even after adjusting for covariates. The impact of AF on the outcome of patients with PAD was greater in those with CLTI. Further studies are needed to clarify the possible mechanisms underlying these differences.

Reinterventions in Patients with Claudication and Chronic Limb Threatening Ischemia

BACKGROUND

Patients with peripheral artery disease (PAD) present with claudication or chronic limb threatening ischemia (CLTI). CLTI patients have a more advanced stage of atherosclerosis and increased comorbidities compared to claudicants, and are at an elevated risk of major amputation and mortality after lower extremity revascularization (LER). However, the frequency of reinterventions for claudication and CLTI have not been compared. Our hypothesis is that patients with CLTI undergo more frequent reinterventions to prevent major amputation.

METHODS

A single-center retrospective chart review of consecutive patients undergoing lower extremity revascularization (LER) for PAD in 2013-2015 was performed. Patients were stratified based on indication for revascularization into claudication or CLTI. Patient characteristics, outcomes, and reinterventions were compared between the 2 groups.

RESULTS

There were 826 patients undergoing LER and 44% (N = 361) had CLTI. Patients treated for CLTI were more likely to be smokers (P < 0.001), to have diabetes (P< 0.001), chronic renal insufficiency (P< 0.001), end stage renal disease (P< 0.001), and cardiac disease (P< 0.001). CLTI patients were less likely to be on optimal medical management as reflected by decreased rate of aspirin (P< 0.001), ADP receptor/P2Y12 inhibitors (P< 0.001), and statins (P< 0.001) compared to patients with claudication. Patients with CLTI had significantly higher major amputation (3.7% vs. 0.2%, P< 0.001) and mortality (1.4% vs. 0.2%, P = 0.092) at 30 days. At long-term follow up, patients with CLTI had higher rates of major amputation (15.5% vs. 1.3%, P < 0.001) and mortality (37.1% vs. 18.1%, P < 0.001) compared to patients with claudication. There was a significant difference in mean follow-up time between the 2 cohorts (claudication: 3.7 ± 1.5 years versus CLTI: 2.6 ± 1.8 years, P < 0.001). There was no significant difference in the ipsilateral reintervention rate between the 2 groups (claudication: 39.6% vs. CLTI: 42.7%, P = 0.37) or the mean number of ipsilateral reinterventions (claudication: 2.0 ± 1.6 vs. CLTI: 2.0 ± 1.7). However, after adjusting for follow-up time, the mean number of reinterventions per year was significantly higher for CLTI patients compared to patients with claudication (1.4 ± 2.2 vs. .6 ± 0.7 intervention per year, P < 0.001).

CONCLUSIONS

Patients undergoing LER for CLTI undergo more frequent reinterventions over time compared to patients treated for claudication. Research on reinterventions after LER should include reporting of the frequency of reintervention adjusted for the follow up period in addition to the reintervention rate defined as the percentage of patients undergoing reintervention.

Sex-based differences in loss of independence after lower extremity bypass surgery

INTRODUCTION

This study analyzes sex-based differences in the risk of discharge to a nonhome facility (loss of independence) after lower extremity revascularization and resultant outcomes.

METHODS

Data from the NSQIP database for years 2015-2017 was utilized to assess sex-based differences in loss of independence and associated unplanned readmission and 30-day amputation using chi-square, student t-test, and multivariate logistic regression analyses where appropriate.

RESULTS

There was increased loss of independence in women (34.9% vs. 26.1 %, p < .01) and associated increase in unplanned readmission (18.4% vs. 13.6 %, p = .01) and length of stay (12.1 days vs 6.5 days, p < .01). Endovascular revascularization was associated with decreased likelihood of loss of independence (OR 0.43, CI 0.36-0.50).

CONCLUSION

Loss of independence after lower extremity bypass surgery affects women more than men and it is associated with worse postoperative outcomes.

Impact of Dual Antiplatelet Therapy after Lower Extremity Revascularization for Chronic Limb Threatening Ischemia (CLTI)

BACKGROUND

The optimal antiplatelet regimen after lower extremity revascularization in patients with chronic limb threatening ischemia (CLTI) is unknown since current recommendations are based on extrapolation of data from trials in coronary artery disease and stroke.

METHODS

We identified all patients undergoing an elective lower extremity revascularization for CLTI in the Vascular Quality Initiative registry discharged on a mono antiplatelet agent (MAPT) or dual antiplatelet therapy (DAPT).

RESULTS

From 2003 to 2018, 50,890 patients underwent revascularization procedures for CLTI, and were discharged on MAPT or DAPT. Of these, 33,781 patients underwent endovascular therapy (EVT) and 17,109 patients underwent open surgery (OS) procedures. The rate of major amputation at 30 days in the target limb in the EVT group was 0.3% and 0.4% in the OS group (P=.22). On Kaplan Meier analyses, patients on MAPT at discharge had a higher risk 1-year major amputation compared to DAPT after EVT but not after OS procedures. Patients on MAPT had lower overall survival and amputation free survival (AFS) at 30 days and 1 year compared to DAPT after both EVT and OS. At 1 year, the MAPT group was at higher risk for target lesion re-intervention after EVT compared to the DAPT group (15.9% vs. 13%, P= .0012). There was no significant difference in thrombosis at 1 year between MAPT and DAPT groups either after EVT (3.9% vs. 3.7%; P = .3048) or OS (3.1% vs. 3.2%; P= .2893). On cox regression analysis, DAPT was associated with improved survival but not major amputation after both EVT and OS.

CONCLUSIONS

In CLTI patients, DAPT at the time of discharge has a positive impact on AFS and overall survival after both EVT and OS as well as target lesion re-intervention after EVT. DAPT was not associated with a positive impact on major amputation after either EVT or OS.

Association between neuraxial anaesthesia or general anaesthesia for lower limb revascularisation surgery in adults and clinical outcomes: population based comparative effectiveness study

OBJECTIVE

To examine the associations between neuraxial anaesthesia or general anaesthesia and clinical outcomes, length of hospital stay, and readmission in adults undergoing lower limb revascularisation surgery.

DESIGN

Comparative effectiveness study using linked, validated, population based databases.

SETTING

Ontario, Canada, 1 April 2002 to 31 March 2015.

PARTICIPANTS

20 988 patients Ontario residents aged 18 years or older who underwent their first lower limb revascularisation surgery in hospitals performing 50 or more of these surgeries annually.

MAIN OUTCOME MEASURES

Primary outcome was 30 day all cause mortality. Secondary outcomes were in-hospital cardiopulmonary and renal complications, length of hospital stay, and 30 day readmissions. Multivariable, mixed effects regression models, adjusting for patient, procedural, and hospital characteristics, were used to estimate associations between anaesthetic technique and outcomes. Robustness of analyses were evaluated by conducting instrumental variable, propensity score matched, and survival sensitivity analyses.

RESULTS

Of 20 988 patients who underwent lower limb revascularisation surgery, 6453 (30.7%) received neuraxial anaesthesia and 14 535 (69.3%) received general anaesthesia. The percentage of neuraxial anaesthesia use ranged from 0.6% to 90.6% across included hospitals. Furthermore, use of neuraxial anaesthesia declined by 17% over the study period. Death within 30 days occurred in 204 (3.2%) patients who received neuraxial anaesthesia and 646 (4.4%) patients who received general anaesthesia. After multivariable, multilevel adjustment, use of neuraxial anaesthesia compared with use of general anaesthesia was associated with decreased 30 day mortality (absolute risk reduction 0.72%, 95% confidence interval 0.65% to 0.79%; odds ratio 0.68, 95% confidence interval 0.57 to 0.83; number needed to treat to prevent one death=139). A similar direction and magnitude of association was found in instrumental variable, propensity score matched, and survival analyses. Use of neuraxial anaesthesia compared with use of general anaesthesia was also associated with decreased in-hospital cardiopulmonary and renal complications (odds ratio 0.73, 0.63 to 0.85) and a reduced length of hospital stay (-0.5 days, -0.3 to-0.6 days).

CONCLUSIONS

Use of neuraxial anaesthesia compared with general anaesthesia for lower limb revascularisation surgery was associated with decreased 30 day mortality and hospital length of stay. These findings might have been related to reduced cardiopulmonary and renal complications after neuraxial anaesthesia and support the increased use of neuraxial anaesthesia in patients undergoing these surgeries until the results of a large, confirmatory randomised trial become available.