Predictors of surgical site infection after open lower extremity revascularization.

Surgical site infection (SSI) after open lower extremity bypass (LEB) is a serious complication leading to an increased rate of graft failure, hospital readmission, and health care costs. This study sought to identify predictors of SSI after LEB for arterial occlusive disease and also potential modifiable factors to improve outcomes. Data from a statewide cardiovascular consortium of 35 hospitals were used to obtain demographic, procedural, and hospital risk factors for patients undergoing elective or urgent open LEB between January 2012 and June 2015. Bivariate comparisons and targeted maximum likelihood estimation were used to identify independent risk factors of SSI. Adjusted odds ratios (ORs) were calculated for patient demographics, comorbidities, operative details, and hospital-level factors. Our study population included 3033 patients who underwent 703 femoral-femoral bypasses, 1431 femoral-popliteal bypasses, and 899 femoral-distal vessel bypasses. An SSI was diagnosed in 320 patients (10.6%) ≤30 days after the index operation. Adjusted patient and procedural predictors of SSI included renal failure currently requiring dialysis (OR, 4.35; 95% confidence interval [CI], 3.45-5.47; P < .001), hypertension (OR, 4.29; 95% CI, 2.74-6.72; P < .001), body mass index ≥25 kg/m2 (OR, 1.78; 95% CI, 1.23-2.57; P = .002), procedural time >240 minutes (OR, 2.95; 95% CI, 1.89-4.62; P < .001), and iodine-only skin preparation (OR, 1.73; 95% CI, 1.02-2.91; P = .04). Hospital factors associated with increased SSI included hospital size <500 beds (OR, 2.22; 95% CI, 1.09-4.55; P = .028) and major teaching hospital (OR, 1.66; 95% CI, 1.07-2.58; P = .024). SSI resulted in increased risk of major amputation and surgical reoperation (P < .01), but did not affect 30-day mortality. SSI after LEB is associated with an increase in rate of amputation and reoperation. Several patient, operative, and hospital-related risk factors that predict postoperative SSI were identified, suggesting that targeted improvements in perioperative care may decrease complications and improve vascular patient outcomes.

Davis FM ，Sutzko DC ，Grey SF ，Mansour MA ，Jain KM ，Nypaver TJ ，Gaborek G ，Henke PK ... -  《-》

Predictors of surgical site infection after open lower extremity revascularization.

Surgical site infection (SSI) after open surgery for lower extremity revascularization is a serious complication that may lead to graft infection, prolonged hospitalization, and increased cost. Rates of SSI after revascularization vary widely, with most studies reported from single institutions. The objective of this study was to describe the rate and predictors of SSI after surgery for arterial occlusive disease using national data, and to identify any association between SSI and length of hospital stay, reoperation, graft loss, and mortality. Patients who underwent lower extremity arterial bypass or thromboendarterectomy from 2005-2008 were identified from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) participant use files. Multivariate logistic regression identified predictors of SSI. Odds ratios were adjusted for patient demographics, comorbidities, preoperative laboratory values, and operative factors. The association between SSI and other 30-day outcomes such as mortality and graft failure was determined. Of 12,330 patients who underwent revascularization, 1367 (11.1%) were diagnosed with an SSI within 30 days. Multivariate predictors of SSI included female gender (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.3-1.6), obesity (OR, 2.1; 95% CI, 1.8-2.4), chronic obstructive pulmonary disease (OR, 1.2; 95% CI, 1.0-1.5), dialysis (OR, 1.5; 95% CI, 1.1-2.1), preoperative hyponatremia (OR, 1.2; 95% CI, 1.0-1.4), and length of operation >4 hours (OR, 1.4; 95% CI, 1.2-1.6). SSI was associated with prolonged (>10 days) hospital stay (OR, 1.8; 95% CI, 1.4-2.1) and higher rates of 30-day graft loss (OR, 2.3; 95% CI, 1.7-3.1) and reoperation (OR, 3.7; 95% CI, 3.1-4.6). SSI was not associated with increased 30-day mortality. SSI is a common complication after open revascularization and is associated with a more than twofold increased risk of early graft loss and reoperation. Several patient and operation-related risk factors that predict postoperative SSI were identified, suggesting that targeted improvements in perioperative care may decrease complications and improve outcomes in this patient population.

Greenblatt DY ，Rajamanickam V ，Mell MW 《-》

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

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. 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. 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. 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.

Stewart LM ，Spangler EL ，Sutzko DC ，Pearce BJ ，McFarland GE ，Passman MA ，Patterson MA ，Haverstock B ，Unger K ，Novak Z ，Beck AW ... -  《-》

Outcomes of open and endovascular lower extremity revascularization in active smokers with advanced peripheral arterial disease.

Concern over perioperative and long-term durability of lower extremity revascularizations among active smokers is a frequent deterrent for vascular surgeons to perform elective lower extremity revascularization. In this study, we examined perioperative outcomes of lower extremity endovascular (LEE) revascularization and open lower extremity bypass (LEB) in active smokers with intermittent claudication (IC) and critical limb ischemia (CLI). Active smokers undergoing LEE or LEB from 2011 to 2014 were identified in the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) targeted vascular data set. Patient demographics, comorbidities, anatomic features, and perioperative outcomes were compared between LEE and LEB procedures. Subgroup analysis was performed for patients undergoing revascularization for IC and CLI independently. From 2011 to 2014, 4706 lower extremity revascularizations were performed in active smokers (37% of all revascularizations). In this group, 1497 were LEE (55.6% for CLI, 13.4% for below-knee pathology) and 3209 were LEB (68.9% CLI, 34.7% below-knee). Patients undergoing LEE had higher rates of female gender, hypertension, end-stage renal disease, and diabetes (all P ≤ .02). LEE patients also had a higher frequency of prior percutaneous interventions (22.7% vs 17.2%; P < .01) and preoperative antiplatelet therapy (82.3% vs 78.7%; P = .02). On risk-adjusted multivariate analysis, LEE patients had higher need for reintervention on the treated arterial segment than LEB (5.1% vs 5.2%; odds ratio [OR], 1.52; 95% confidence interval [CI], 1.08-2.13; P = .02) but had lower wound complications (3.1% vs 13.2%; OR, 0.32; 95% CI, 0.23-0.45; P < .01) and no statistically significant difference in 30-day mortality (0.6% vs 0.9%), myocardial infarction or stroke (1.1% vs 2.6%), or major amputation (3.2% vs 2.1%) in the overall cohort of active smokers. In the IC subgroup, myocardial infarction or stroke was significantly higher in the LEB group (1.9% vs 0.6%; OR, 1.83; 95% CI, 1.17-1.97; P = .03), although no difference was found in the CLI subgroup (2.8% vs 1.4%; OR, 0.75; 95% CI, 0.37-1.52; P = .42,). Also in IC group, there was a trend for lower major amputation rates ≤30 days in the LEE group, whereas in the CLI group, LEE had a trend toward higher risk of early amputation compared with LEB. In active smokers, LEB for IC and CLI requires fewer reinterventions but is associated with a higher rate of postoperative wound complications compared with LEE revascularization. However, the risk for limb amputation is higher in actively smoking patients when treated by LEE compared with LEB for CLI. Importantly, cardiovascular complications are significantly higher in actively smoking patients with IC undergoing LEB compared with LEE. This additional cardiovascular risk should be carefully weighed when proposing LEB for actively smoking patients with nonlimb-threatening IC.

Chen SL ，Whealon MD ，Kabutey NK ，Kuo IJ ，Sgroi MD ，Fujitani RM ... -  《-》

Factors associated with surgical site infection after lower extremity bypass in the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI).

Surgical site infection (SSI) is a major source of morbidity after infrainguinal lower extremity bypass (LEB). This study examines processes of care associated with in-hospital SSI after LEB and identifies factors that could potentially be modified to improve outcomes. The Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) registry (2003 to 2012) was queried to identify in-hospital SSI after 7908 consecutive LEB procedures performed by 365 surgeons at 91 academic and community hospitals in 45 states. Variables associated with SSI were identified using multivariable logistic regression and hierarchical clustering. Expected and observed SSI rates were calculated for each hospital. The overall in-hospital SSI rate after LEB was 4.8%. Univariate analysis showed that obesity, dialysis, tissue loss, preoperative ankle-brachial index <0.35, distal target, vein graft conduit, continuous incision for vein harvest, transfusion >2 units of packed red blood cells, procedure time >220 minutes, and estimated blood loss >100 mL were associated with higher SSI rates, whereas chlorhexidine (compared with iodine) skin preparation was protective. Multivariable analysis showed independent predictors of SSI included ankle-brachial index <0.35 (odds ratio [OR], 1.53; 95% confidence interval [CI], 1.03-2.30, P < .04), transfusion >2 units (OR, 3.30; 95% CI, 2.17-5.02; P < .001), and procedure time >220 minutes (OR, 2.11; 95% CI, 1.05-4.23; P < .04). Chlorhexidine was protective against SSI (OR, 0.53; 95% CI, 0.35-0.79; P = .002). Stratified analyses based on the presence of tissue loss yielded similar results. Across VQI hospitals, observed SSI rates ranged from 0% to 30%, whereas expected SSI rates adjusted by the four independent predictors ranged from 0% to 7.2%. In-hospital SSI after LEB varies substantially across VQI hospitals. Three modifiable processes of care (transfusion rate, procedure time, and type of skin preparation) were identified and may be used by hospitals to reduce SSI rates. This study demonstrates the value of the SVS VQI detailed shared clinical registry to identify improvement opportunities directly pertinent to providers that are not available in typical administrative data sets.

Kalish JA ，Farber A ，Homa K ，Trinidad M ，Beck A ，Davies MG ，Kraiss LW ，Cronenwett JL ，Society for Vascular Surgery Patient Safety Organization Arterial Quality Committee ... -  《-》