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Critical limb ischemia (CLI) is a frequent and major vascular problem and can lead to amputation and death despite surgical revascularization. Women have been shown to have 3 to 4 per cent lower revascularization rates for CLI compared with men as well as inferior outcomes. We hypothesize that this difference is a result of women being more likely admitted to low-volume hospitals, which in turn perform fewer revascularizations. Prospective cohort study. Data from the Nationwide Inpatient Sample 2007 to 2010 were used to identify admissions with primary International Classification of Diseases-9 codes for CLI (International Classification of Diseases-9 codes: 440.22, 440.23, 440.24, 707.1, 707.10-707.15, or 707.19). Hospitals were grouped in quintiles by annual revascularization procedures. Bivariate analyses were performed and multivariable logistic regression was used to analyze the odds of revascularization, amputation, and mortality while controlling for patient and hospital-level factors. Of 113,631 admissions, 54,370 (47.8%) were women, who were more likely admitted to low-volume hospitals (very low: 49.6% vs very high: 47.1%; P < 0.001). Revascularization rates were lower in women (31.6% vs 35.1%, P < 0.001) across all volume quintiles, whereas the difference was greatest in the use of open surgical revascularization (12.5% vs 16.0%, P < 0.001). In multivariable analysis, female gender [odds ratio (OR) 0.87, 95% confidence interval (CI) 0.83-0.92, P < 0.001] and very-low hospital volume (OR 0.21, 95% CI 0.17-0.26, P < 0.001) were both significantly associated with lower rates of revascularization. Women had lower odds of major amputation compared with men (OR 0.75, 95% CI 0.69-0.82, P < 0.001), whereas treatment in a very high-volume hospital was associated with increased odds for amputation (OR 1.37, 95% CI 1.09-1.73, P = 0.008). Neither gender nor hospital volume were independently associated with in-hospital mortality in the multivariable regression model. Women are more likely to be admitted to low-volume hospitals for treatment of CLI. Because of this, they are less likely to undergo revascularization, although they also had lower rates of major amputation.

Objective: Historically, edge stenosis and late thrombosis limited the effectiveness of adjunctive endovascular brachytherapy (EVBT) for in-stent restenosis (ISR) after percutaneous transluminal angioplasty (PTA) and stenting. We evaluated an updated protocol of PTA and EVBT for ISR among patients with lower extremity occlusive disease., Methods: This is a retrospective, single-center review of patients treated with PTA and EVBT for ISR in the iliac and femoropopliteal segments between 2004 and 2012. A dose of 20 Gy was given at a depth of 0.5 mm beyond the radius of the largest PTA balloon using iridium 192, with at least 2-cm-long margins of radiation coverage proximal and distal to the injured area. Stents were assessed for patency by duplex ultrasound imaging at 1, 3, 6, 9, 12, and 18 months and then yearly. The primary end point was freedom from ≥50% restenosis in the treated segment at 6 months, 1 year, and 2 years. Patency data were estimated using the Kaplan-Meier method. Secondary end points were early and late thrombotic occlusion., Results: Among 42 consecutive cases in 35 patients of EVBT for ISR in common or external iliac (9 [20.8%]) and superficial femoral or popliteal (33 [76.7%]) arteries, or both, 21 patients (50%) had claudication, asymptomatic hemodynamically significant stenoses were identified on duplex ultrasound imaging in 16 (38.1%), and 4 (9.8%) had critical limb ischemia. Mean treated length was 23.5 ± 12.3 cm over a mean duration of 16.1 ± 9.6 minutes. There was one technical failure (2.3%). Median post-EVBT follow-up time was 682 days (range, 1-2262 days). There were two (4.9%) and five (11.9%) cases of early and late thrombotic occlusions, respectively. There was one death, believed to be secondary to acute coronary syndrome. Primary, assisted primary, and secondary patency in the entire cohort was 75.2%, 89.1%, and 89.1%, respectively, at 1 year and 63.7%, 80.6%, and 85.6%, respectively, at 2 years., Conclusions: This contemporary protocol of PTA and adjunctive EVBT for lower extremity ISR, which is updated from those used in prior trials and includes a surveillance strategy that identifies at-risk stents for reintervention before occlusion, may be a promising treatment for lower extremity ISR at institutions where a close collaboration between vascular surgeons and radiation oncologists is feasible., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: Despite patent vein bypass grafts, some patients with critical limb ischemia (CLI) receive major amputations. We analyzed the predictive factors leading to major amputation in the presence of patent lower extremity bypass (LEB) grafts., Methods: Data from the Project of Ex-Vivo vein graft Engineering via Transfection III (PREVENT III), a large prospective randomized trial of 1404 patients who underwent LEB with vein graft for CLI, were queried for outcomes. The primary outcome was major amputation with patent (PMA) LEB compared with patients with patent LEB who achieved limb salvage (PLS). The population excluded those who received amputation for occluded grafts. A Cox proportional hazard model identified independent predictors., Results: Of 1404 LEB patients, 162 (11.5%) had major amputation: 89 (6.3%) with patent and 73 (5.2%) with occluded LEB. For PMA, 21 of 89 (23.6%) developed critical stenosis and 11 of 21 (52.4%) were revised. For PLS, 460 of 1242 (37.0%) developed critical stenosis and 351 of 460 (76.3%) were revised. Predictive patient factors included having preoperative gangrene (vs rest pain; hazard ratio [HR], 3.504; 95% confidence interval [CI], 1.533-8.007; P = .0029), diabetes (HR, 1.800; 95% CI, 1.006-3.219; P = .0477), black (vs white) race (HR, 1.779; 95% CI, 1.051-3.011; P = .0321), baseline creatinine clearance <25 mL/min (vs >65 mL/min; HR, 1.759; 95% CI, 1.016-3.048; P = .0439), prior history of coronary artery bypass grafting (HR, 1.702; 95% CI, 1.080-2.683; P = .0221), and lower baseline activity quality of life score (HR, 1.401; 95% CI, 1.105-1.778; P = .0054). Postoperative wound factors included gangrenous changes (HR, 5.830; 95% CI, 1.647-20.635; P = .0063), surgical wound necrosis (HR, 5.319; 95% CI, 1.478-19.146; P = .0105), deep (vs superficial) wound infection (HR, 3.815; 95% CI, 1.220-11.927; P = .0213), and wound healing abnormally (HR, 3.754; 95% CI, 1.061-13.278; P = .0402). Associated postoperative consequences leading to PMA included having recurrent CLI symptoms (HR, 2.915; 95% CI, 1.816-4.681; P < .0001), a severe (vs mild) adverse event (HR, 2.751; 95% CI, 1.391-5.443; P = .0036), fewer percutaneous revisions (HR, 2.425; 95% CI, 1.573-3.740; P < .0001), discharge on low-molecular-weight heparin (HR, 2.087; 95% CI, 1.309-3.326; P = .0020), and decreasing days to critical stenosis/occlusion/revision/amputation (HR, 1.010; 95% CI, 1.007-1.012; P < .0001)., Conclusions: Whereas a patent vein graft is important to all vascular surgeons, additional factors should be considered in trying to attain limb salvage for patients with CLI. These factors include intervening surgically before CLI has progressed to a state of gangrene or limited activity and optimizing nutrition, diabetes control, cardiac conditions, and activity level. Revision offers hope for clinical improvement but may be delayed when there is no graft lesion identified. The absence of a graft lesion to revise may also portend amputation despite a patent graft because of nongraft-related factors such as infection. Finally, the experience of a severe (vs mild) adverse event may also result in limb loss despite a patent graft. Systematic efforts to reduce severe adverse events among patients may also lead to increased limb salvage., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: The value and cost-effectiveness of less invasive alternative imaging (AI) modalities (duplex ultrasound scanning, computed tomography angiography, and magnetic resonance angiography) in the care of peripheral arterial disease (PAD) has been reported; however, there is no consensus on their role. We hypothesized that AI utilization is low compared with angiography in the United States and that patient and hospital characteristics are both associated with AI utilization., Methods: The Nationwide Inpatient Sample (2007-2010) was used to identify patients with an International Classification of Diseases-Ninth Edition diagnosis of claudication or critical limb ischemia (CLI) as well as PAD treatment (surgical, endovascular, or amputation). Patients with AI and those with angiography or expected angiography (endovascular procedures without imaging codes) were selected and compared. Multivariable logistic regression was performed for receiving AI stratified by claudication and CLI and adjusting for patient and hospital factors., Results: We identified 290,184 PAD patients, of whom 5702 (2.0%) received AI. Patients with AI were more likely to have diagnosis of CLI (78.8% vs 48.6%; P < .0001) and receive open revascularizations (30.4% vs 18.8%; P < .0001). Van Walraven comorbidity scores (mean [standard error] 5.85 ± 0.22 vs 4.10 ± 0.05; P < .0001) reflected a higher comorbidity burden in AI patients. In multivariable analysis for claudicant patients, AI was associated with large bed size (odds ratio [OR], 3.26, 95% confidence interval [CI], 1.16-9.18; P = .025), teaching hospitals (OR, 1.97; 95% CI, 1.10-3.52; P = .023), and renal failure (OR, 1.52; 95% CI, 1.13-2.05; P = .006). For CLI patients, AI was associated with black race (OR, 1.53; 95% CI, 1.13-2.08; P = .006) and chronic heart failure (OR, 1.29; 95% CI, 1.04-1.60; P = .021) and was negatively associated with renal failure (OR, 0.80; 95% CI, 0.67-0.95; P = .012). The Northeast and West regions were associated with higher odds of AI in claudicant patients (OR, 2.41; 95% CI, 1.23-4.75; P = .011; and OR, 2.59; 95% CI, 1.34-5.02; P = .005, respectively) and CLI patients (OR, 4.31; 95% CI, 2.20-8.36; P < .0001; and OR, 2.18; 95% CI, 1.12-4.22; P = .021, respectively). Rates of AI utilization across states were not evenly distributed but showed great variability, with ranges from 0.31% to 9.81%., Conclusions: National utilization of AI for PAD is low and shows great variation among institutions in the United States. Patient and hospital factors are both associated with receiving AI in PAD care, and AI utilization is subject to significant regional variation. These findings suggest differences in systems of care or practice patterns and call for a clearer understanding and a more unified approach to imaging strategies in PAD care., (Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Patients with critical limb ischemia (CLI) often undergo revascularization before amputation. The exact relationship between multiple procedures and increased risk of amputation is unclear. We sought to determine the increased risk of amputation for each additional revascularization., Methods: The 2007-2009 California State Inpatient Database (SID) was used to identify a cohort of CLI patients undergoing revascularization and conduct a time-to-event analysis for patients undergoing one or more revascularization procedures. One-year estimates were generated with Kaplan-Meier curves and compared with the log-rank test. The Wei-Lin-Weissfeld (WLW) marginal proportional hazards model was used to assess independent effects of number of revascularization procedures on amputation and death., Results: A total of 11,190 patients with CLI underwent revascularization between July 2007 and December 2009. Their mean age was 71.0 years (interquartile range 62-80 years) and 6255 (55.9%) were male. Over half the subjects (55.2%) were smokers and there was a high burden of comorbidities in the cohort. One-year estimates of amputation by number of revascularizations (1: 23.3%; 2: 27.1%; 3: 30.3%; 4: 26.7%; 5(+): 28.6%; P < 0.001) and death (1: 18.7%; 2: 21.1%; 3: 26.3%; 4: 23.6%; 5+: 32.1%; P = 0.012) increased significantly as procedures increased. In the WLW model for amputation, the hazard increased significantly for patients with 2 revascularization versus 1 (HR = 1.22; 95% CI 1.09-1.37; P = 0.001) and 3 revascularizations versus 2 (HR = 1.33; 95% CI 1.10-1.62; P = 0.004). In the multivariable WLW models for death, the increase in revascularization procedures for 2 compared with 1 (HR = 1.18; 95% CI 1.04-1.34; P = 0.010) was significant., Conclusions: The risk of amputation increases with each additional revascularization procedure. These findings hold true for both percutaneous transluminal angioplasty only and lower extremity bypass only subsets. In addition, increased revascularization procedures appear to result in an increased risk of death. We advocate for continued communication between clinicians and patients on the true risks and benefits of additional revascularization procedures., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: Hospital readmission after lower extremity bypass is a large cost burden and has become a focal point for policy change directed at disease-specific bundling strategies. The purpose of this study was to evaluate rates and predictors of 30-day readmission from a large, multicenter trial data set., Methods: We analyzed the PRoject of Ex-Vivo vein graft ENgineering via Transfection III (PREVENT III) data set of 1404 critical limb ischemia (CLI) patients undergoing lower extremity vein graft bypass at 83 North American centers. The primary end point was readmission ≤30 days of discharge. Secondary end points included graft patency and limb salvage evaluated in the context of readmission. The data set was split into a two-thirds derivation set and a one-third validation set for the purposes of creating a risk prediction model. A whole number integer risk score was assigned to independent predictors of readmission. Summary risk scores were collapsed into categories and defined as low (0-1 points), medium (2-5 points), and high (>5 points)., Results: We analyzed 1356 vein graft bypass patients, of which 23 (1.7%) died in-hospital and were excluded from the readmission analyses. In the derivation data set of 866 patients, 211 (24.4%) were readmitted ≤30 days of discharge. The most common reasons for readmission were wound infection in index leg (39.8%), an additional procedure in the index leg (20.8%), and nonvascular reasons (19%). By multivariable analysis, factors associated with 30-day hospital readmission (odds ratio [95% confidence limits]) included female gender (1.5 [1.0, 2.1]), current smoking (1.6 [1.1, 2.4]), in-hospital loss of graft patency (1.8 [1.0, 3.2]), dialysis (2.0 [1.2, 3.2]), and tissue loss (1.7 [1.1, 2.5]). In the derivation set, rates of readmission correlated to risk category. The 30-day readmission rates were 15.6% for low-risk patients (0-1 points), 24.1% for moderate-risk (2-5 points) patients, and 38.0% for high-risk (>5 points) patients. Similarly, in the validation set, the rates were 16.5%, 25.4%, and 38.1% for low-, medium-, and high-risk groups, respectively. Thirty-day readmission was not associated with loss of long-term graft patency but was associated with long-term limb loss (hazard ratio, 2.1; 95% confidence interval, 1.4-3.1; P = .0002)., Conclusions: Readmission after lower extremity bypass for CLI is common (24%). Certain characteristics, such as female gender, current smoking, dialysis-dependence, tissue loss, and in-hospital graft-related events, are associated with increased risk. Readmission is associated with long-term limb loss. These data provide benchmark values for this complex patient population and may prove useful when hospital readmission is used as a quality metric for hospital performance., (Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Objective: Major amputation is associated with increased short-term healthcare resource utilization (RU), early mortality, and socioeconomic status (SES) disparities. Our objective is to study patient-specific and SES-related predictors of long-term RU and survival after amputation., Methods: This retrospective analysis identified 364 adult patients who underwent index major amputation for critical limb ischemia from January 1995 through December 2000 at two tertiary centers with outcomes through December 2010. Age, gender, SES (race, income, insurance, and marital status), comorbidities (congestive heart failure [CHF], diabetes, diabetes with complications, and renal failure [RF]), subsequent procedures, cumulative length of stay (cLOS), and mortality were analyzed. Bivariate and multivariate Poisson regression for subsequent procedures and cLOS and Cox proportional hazard modeling for all-cause mortality were undertaken., Results: During a mean follow-up of 3.25 years, amputation patients had mean cLOS of 71.2 days per person-year (median, 17.6), 19.5 readmissions per person-year (median, 2.1), 0.57 amputation-related procedures (median, 0), and 0.31 cardiovascular procedures (median, 0). Below-knee amputation as the index procedure was performed in 70% of patients, and 25% had additional amputation procedures. Of readmissions at ≤ 30 days, 52% were amputation-related. Overall mortality during follow-up was 86.9%; 37 patients (10.2%) died within 30 days. Among patients surviving >30 days, multivariate Poisson regression demonstrated that younger age (incidence rate ratio [IRR], 0.98), public insurance (IRR, 1.63), CHF (IRR, 1.60), and RF (IRR, 2.12) were associated with increased cLOS. Diabetes with complications (IRR, 1.90) and RF (IRR, 2.47) affected subsequent amputation procedures. CHF (IRR, 1.83) and RF (IRR, 3.67) were associated with a greater number of cardiovascular procedures. Cox proportional hazard modeling indicated older age (hazard ratio [HR], 1.04), CHF (HR, 2.26), and RF (HR, 2.60) were risk factors for decreased survival. Factors associated with SES were not significantly related to the outcomes., Conclusions: This study found that RU is high for amputees, and increased RU persists beyond the perioperative period. Results were similar across SES indices, suggesting higher SES may not be protective against poor outcomes when limb salvage is no longer attainable. These findings support the hypothesis that SES disparities may be more modifiable during earlier stages of care for critical limb ischemia., (Copyright © 2013. Published by Mosby, Inc.)

Objective: Disparities in limb salvage procedures may be driven by socioeconomic status (SES) and access to high-volume hospitals. We sought to identify SES factors associated with major amputation in the setting of critical limb ischemia (CLI)., Methods: The 2003-2007 Nationwide Inpatient Sample was queried for discharges containing lower extremity revascularization (LER) or major amputation and chronic CLI (N = 958,120). The Elixhauser method was used to adjust for comorbidities. Significant predictors in bivariate logistic regression were entered into a multivariate logistic regression for the dependent variable of amputation vs LER., Results: Overall, 24.2% of CLI patients underwent amputation. Significant differences were seen between both groups in bivariate and multivariate analysis of SES factors, including race, income, and insurance status. Lower-income patients were more likely to be treated at low-LER-volume institutions (odds ratio [OR], 1.74; P < .001). Patients at higher-LER-volume centers (OR, 15.16; P <.001) admitted electively (OR, 2.19; P < .001) and evaluated with diagnostic imaging (OR, 10.63; P < .001) were more likely to receive LER., Conclusions: After controlling for comorbidities, minority patients, those with lower SES, and patients with Medicaid were more likely receive amputation for CLI in low-volume hospitals. Addressing SES and hospital factors may reduce amputation rates for CLI., (Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Limb salvage, operative mortality and short and long term graft patency have long been important variables for assessment of infrainguinal arterial reconstructions. More recently it is now appreciated that patient and society oriented measures of outcomes in determining the effectiveness of any surgical procedure are also important. In particular, the impact of an intervention on a patient's overall quality of life (QOL) and whether it is cost effective in achieving improvement of QOL are questions of increasing importance from the patient's perspective and from the perspective of those who must make difficult health policy decisions. This chapter reviews the cost effectiveness and impact of infrainguinal bypass on patient perceived quality of life in patients with intermittent claudication and patients with critical limb ischemia. The data are not robust but suggest favorable impact of infrainguinal bypass in terms of both QOL and cost effectiveness in both patients with intermittent claudication and critical limb ischemia.

Background: Vein bypass surgery is an effective therapy for atherosclerotic occlusive disease in the coronary and peripheral circulations; however, long-term results are limited by progressive attrition of graft patency. Failure of vein bypass grafts in patients with critical limb ischemia results in morbidity, limb loss, and additional resource use. Although technical factors are known to be critical to the success of surgical revascularization, patient-specific risk factors are not well defined. In particular, the relationship of race/ethnicity and gender to the outcomes of peripheral bypass surgery has been controversial., Methods and Results: We analyzed the Project of Ex Vivo Vein Graft Engineering via Transfection III (PREVENT III) randomized trial database, which included 1404 lower extremity vein graft operations performed exclusively for critical limb ischemia at 83 North American centers. Trial design included intensive ultrasound surveillance of the bypass graft and clinical follow-up to 1 year. Multivariable modeling (Cox proportional hazards and propensity score) was used to examine the relationships of demographic variables to clinical end points, including perioperative (30-day) events and 1-year outcomes (vein graft patency, limb salvage, and patient survival). Final propensity score models adjusted for 16 covariates (including type of institution, technical factors, selected comorbidities, and adjunctive medications) to examine the associations between race, gender, and outcomes. Among the 249 black patients enrolled in PREVENT III, 118 were women and 131 were men. Black men were at increased risk for early graft failure (hazard ratio [HR], 2.832 for 30-day failure; 95% confidence interval [CI], 1.393 to 5.759; P=0.0004), even when the analysis was restricted to exclude high-risk venous conduits. Black patients experienced reduced secondary patency (HR, 1.49; 95% CI, 1.08 to 2.06; P=0.016) and limb salvage (HR, 2.02; 95% CI, 1.27 to 3.20; P=0.003) at 1 year. Propensity score models demonstrate that black women were the most disadvantaged, with an increased risk for loss of graft patency (HR, 2.02 for secondary patency; 95% CI, 1.27 to 3.20; P=0.003) and major amputation (HR, 2.38; 95% CI, 1.18 to 4.83; P=0.016) at 1 year. Perioperative mortality and 1-year mortality were similar across race/gender groups., Conclusions: Black race and female gender are risk factors for adverse outcomes after vein bypass surgery for limb salvage. Graft failure and limb loss are more common events in black patients, with black women being a particularly high-risk group. These data suggest the possibility of an altered biological response to vein grafting in this population; however, further studies are needed to determine the mechanisms underlying these observed disparities in outcome.

Background: Infrainguinal bypass (IB) surgery is an effective means of improving arterial circulation to the lower extremity for patients with critical limb ischemia (CLI). However, wound complications (WC) of the surgical incision following IB can impart significant morbidity., Methods: A retrospective analysis of WC from the 1404 patients enrolled in a multicenter clinical trial of vein bypass grafting for CLI was performed. Univariate and multivariable regression models were used to determine WC predictors and associated outcomes, including graft patency, limb salvage, quality of life (QoL), resource utilization (RU), and mortality., Results: A total of 543 (39%) patients developed a reported WC within 30 days of surgery, with infections (284, 52%) and hematoma/hemorrhage (121, 22%) being the most common type. Postoperative anticoagulation (odds ratio [OR], 1.554; 95% confidence interval [CI] 1.202 to 2.009; P = .0008) and female gender (OR, 1.376; 95% CI, 1.076 to 1.757; P = .0108) were independent factors associated with WC. Primary, primary-assisted, and secondary graft patency rates were not influenced by the presence of WC; though, patients with WC were at increased risk for limb loss (hazard ratio [HR], 1.511; 95% CI 1.096 to 2.079; P = .0116) and higher mortality (HR, 1.449; 95% CI 1.098 to 1.912; P = .0089). WC was not significantly associated with lower QoL at 3 months (4.67 vs 4.79, P = .1947) and 12 months (5.02 vs 5.13, P = .2806). However, the subset of patients with serious WC (SWC) demonstrated significantly lower QoL at 3 months compared with patients without WC, (4.43 vs 4.79, respectively, P = .0166), though this difference was not seen at 12 months (4.94 vs 5.13, P = .2411). Patients with WC had higher RU than patients who did not have WC. Mean index length of hospital stay (LOS) was 2.3 days longer, mean cumulative 1-year LOS was 8.1 days longer, and mean number of hospitalizations was 0.5 occurrences greater for patients with WC compared with patients without WC (all P < .0001)., Conclusions: WC is a frequent complication of IB for CLI, associated with increased risk for major amputation, mortality, and greater RU. Further detailed investigation into the link between female gender and oral anticoagulation use with WC may help identify causes of WC and perhaps prevent or lessen their occurrence.

Objective: Resource utilization (RU) in the care of patients with critical limb ischemia (CLI) is not well quantified. We present a cohort study to quantify in-hospital RU and analyze the role of tissue loss (TL), comorbidities, and vascular graft-related events (GREs) in patients undergoing peripheral bypass for CLI., Methods: A retrospective analysis of 1404 patients enrolled in a multicenter clinical trial (PREVENT III) of vein bypass grafting for CLI was performed with analysis of RU during the 1-year follow-up period. Univariate and multivariable linear regressions were performed to determine RU predictors and outcomes., Results: Compared with patients with rest pain, patients presenting with TL as the indication for bypass surgery had a longer index length of stay (mean, 9.8 vs 6.2 days), more rehospitalizations (mean, 1.6 vs 1.2), and a longer cumulative length of stay (mean, 27.7 vs 17.3 days; P < .0001 for all comparisons). Rehospitalizations over the ensuing year were for additional procedures (37.5%), wound infection (14.6%), graft failure (10.7%), and other cardiovascular (10%) and noncardiovascular (26%) reasons. Early GRE (stenosis > or =70%, thrombosis, revision, or major amputation within 30 days) occurred in 162 (11.5%) patients, resulting in a longer index length of stay (mean, 11.8 vs 8.6 days; P = .0002) and cumulative length of stay (mean, 25.9 vs 24.6 days; P = .0043), but no difference in the number of rehospitalizations (mean, 1.6 vs 1.5 days; P = .3272). During the 1-year follow-up, 554 (39.5%) patients had GREs, and this resulted in more rehospitalizations (mean, 2.1 vs 1.1; P < .0001) and a longer cumulative length of stay (mean, 28.2 vs 21.9 days; P < .0001) compared with patients without GRE. Multivariable analysis demonstrated the highly positive association of TL (hazard ratio [HR], 1.75) and early GRE (HR, 1.77) with the index length of stay, whereas comorbidities-namely, dialysis dependency (HR, 1.31), nonsmoking status (HR, 1.29), hypertension (HR, 1.26), and increasing age (HR, 1.01)-also had strong effects. The effect of TL and GRE on later RU (number of rehospitalizations and cumulative length of stay) was present but less pronounced than patient comorbidities (namely, dialysis)., Conclusions: The stage of disease at presentation (TL vs rest pain) and the patency of the bypass graft (freedom from GRE) are critical determinants of RU over the first year after limb-salvage surgery. These effects predominate early (index length of stay) and persist through 1 year. Patient-specific factors, particularly dialysis-dependent renal failure, are also critical comorbidities affecting RU in these patients.

Diagnosis of hand ischemia secondary to an arteriovenous (AV) hemodialysis access is predominantly based on clinical findings. Occasionally, this diagnosis is unclear and more objective diagnostic testing is needed. No validated method of objective testing currently exists. The purpose of this study is to evaluate digital pressure measurements in the diagnosis of AV access-induced hand ischemia. A case-control study of 40 patients with an upper extremity AV access consisted of 15 patients (38%) with clinical AV access-induced hand ischemia and 25 patients (62%) without clinical evidence of ischemia. Arterial pressure in the third finger ipsilateral to the AV access was measured by digital photoplethysmography. Basal digital pressure (BDP), digital to contralateral brachial index (DBI), and change in digital pressure with access compression (CDP) were determined. Logistic regression modeling with gains tables and ROC calculations were used to determine optimal test thresholds and to test model discrimination for predicting AV access-induced hand ischemia. The mean BDP (30 vs 102 mmHg; p < 0.001) and mean DBI (0.3 vs 0.8; p < 0.001) were significantly lower in patients with AV access-induced hand ischemia than in those without. The accuracy for determining hand ischemia using a threshold-adjusted BDP of 60 mmHg was 92% (sensitivity 100%, specificity 87%) and using DBI of 0.4 was 94% (sensitivity 92%, specificity 96%). While the mean CDP was significantly higher in patients with hand ischemia (85 vs 40; p < 0.001), the accuracy for predicting ischemia was marginal (78%). In conclusion, a BDP less than 60 mmHg or a DBI less than 0.4 in a patient with an AV access were highly associated with hand ischemia. CDP's marginal discrimination ability likely stems from the presence of asymptomatic physiologic steal in the group without clinical steal. Nonetheless, CDP may be useful in identifying patients with ischemia who will not benefit from an intervention that specifically targets the AV access.

Background: Patients with critical limb ischemia (CLI) have multiple comorbidities and limited life spans. The ability of infrainguinal vein bypass to improve quality of life (QoL) in patients with CLI has therefore been questioned. Prospective preoperative and postoperative QoL data for patients undergoing lower extremity vein bypass for CLI are presented., Methods: A validated, disease-specific QoL questionnaire (VascuQoL) with activity, symptom, pain, emotional, and social domains and responses scored 1 (lowest QoL) to 7 (best QoL) was administered before surgery and at 3 and 12 months after lower extremity vein bypass for CLI. Changes in QoL at 3 and 12 months after lower extremity vein bypass and multiple predetermined variables potentially influencing QoL after lower extremity vein bypass were analyzed to determine the effect of lower extremity vein bypass on QoL in CLI patients., Results: A total of 1404 patients had lower extremity vein bypass for CLI at 83 centers in the United States and Canada as part of the PREVENT III clinical trial. Surveys were completed in 1296 patients at baseline, 862 patients at 3 months, and 732 patients at 12 months. The global QoL score (mean +/- SD) was 2.8 +/- 1.1 at baseline and was 4.7 +/- 1.4 and 5.1 +/- 1.4 at 3 and 12 months, respectively. Mean changes from baseline at 3 and 12 months were statistically significant (P < .0001). Improved QoL scores extended across all domains. Diabetes and the development of graft-related events were associated with decreased improvement in QoL scores, though the mean relative change from baseline remained positive., Conclusions: Patients with CLI have a low QoL at baseline that is improved at 3 and 12 months after lower extremity vein bypass. QoL improvements are lower in diabetic patients and those who develop graft-related events. Successful revascularization can be expected to improve QoL in patients with CLI, with benefits that are sustained to at least 1 year.

Objective: African Americans (AAs) are at risk for developing diabetes mellitus and atherosclerosis. Whether race influences the results of infrainguinal arterial reconstruction is unclear. The purpose of this study was to compare the results of autogenous infrainguinal bypasses in AAs and Caucasians to determine the association of race with graft function and limb salvage., Methods: This was a retrospective, comparative cohort study of AA and Caucasian patients who had undergone autogenous infrainguinal bypass surgery. Only single-limb bypasses in each patient cohort were considered in this analysis. In patients who had undergone bilateral lower limb bypasses, the first limb bypass was chosen as the index bypass procedure., Results: From January 1985 to December 2003, 1459 autogenous infrainguinal bypasses were performed in 1459 patients for lower limb ischemia. Within this group, 89 AA patients/vein grafts formed the study cohort. The control group comprised 1370 Caucasian patients/vein grafts. Compared with the Caucasian cohort, AA patients were significantly younger (median age, 65 vs 70 years, respectively; P = .001) and predominantly female (57% vs 41%, respectively; P = .002). AA patients also had a higher prevalence of diabetes mellitus, hypertension, cerebrovascular disease, congestive heart failure, and dialysis-dependent renal failure. More AA than Caucasian patients presented with gangrene (34% vs 16%, respectively; P = .001), and more underwent bypass surgery for limb salvage indications (91% vs 81%, respectively; P = .01). The venous conduit used was predominantly the greater saphenous vein (AA, 83%; Caucasian, 85%), and the site of distal anastomosis was at the tibial/pedal level in 67% of AA and 61% of Caucasian patients. Overall morbidity (AA, 28%; Caucasian, 23%) and 30-day mortality (AA, 3%; Caucasian, 3%) were similar. Thirty-day graft failure was significantly greater in AAs than Caucasians (12% vs 5%, respectively; P = .003). The overall 5-year primary graft patency (+/-SE) was significantly worse in AA patients (AA, 52% +/- 6%; Caucasian, 67% +/- 2%; P = .009). The 5-year limb salvage rate (+/-SE) was also significantly worse in AA patients (AA, 81% +/- 5%; Caucasian, 90% +/- 1%; P = .04). With the Cox proportional hazard model, significant risk factors associated with primary graft failure were AA race, age younger than 65 years, female sex, secondary reconstructions, tibial bypasses, and critical limb ischemia. Significant risk factors associated with limb loss were age younger than 65 years, female sex, absence of coronary disease, presence of critical limb ischemia, and secondary reconstructions., Conclusions: Autogenous infrainguinal bypass surgery in AAs is associated with poorer primary graft patency and limb salvage rates compared with those of Caucasians. This may partially account for the higher rate of limb loss in AA patients with peripheral arterial occlusive disease.

Background: Thirty-day unplanned readmission after lower extremity bypass represents a large cost burden and is a logical target for cost-containment strategies. We undertook this study to evaluate factors associated with unplanned readmission after lower extremity bypass. Methods: This is a retrospective analysis from a prospective institutional registry. All lower extremity bypasses for occlusive disease from January 1995 to July 2011 were included. The primary end point was 30-day unplanned readmission. Secondary end points included graft patency and limb salvage. Results: Of 1543 lower extremity bypasses performed, 84.5% were for critical limb ischemia and 15.5% were patients with intermittent claudication. Twenty-seven patients (1.7%) died in-house and were excluded from further analysis. Of 1516 lower extremity bypasses analyzed, 42 (2.8%) were in patients with a planned readmission within 30 days, and 349 (23.0%), in patients with an unplanned readmission. Most unplanned readmissions were wound related (62.9%). By multivariable analysis, preoperative predictive factors for unplanned readmission were dialysis dependence (odds ratio [OR], 1.73; P = .004), tissue loss indication (OR, 1.62; P = .0004), and history of congestive heart failure (OR, 1.43; P = .03). Postoperative predictors included distal inflow source (OR, 1.38; P = .016), in-hospital wound infection (OR, 8.30; P < .0001), in-hospital graft failure (OR, 3.20; P < .0001), and myocardial infarction (OR, 1.96; P < .04). Neither index length of stay nor discharge disposition independently predicted unplanned readmission. Unplanned readmission was associated with loss of assisted primary patency (hazard ratio, 1.39; 95% confidence interval, 1.08-1.80; P = .01) and long-term limb loss (hazard ratio, 1.68; 95% confidence interval, 1.23-2.29; P = .001). Conclusions: Thirty-day unplanned readmission is a frequent occurrence after lower extremity bypass (23.0%). Stratifying patients by risk factors associated with unplanned readmission is essential for quality improvement and equitable resource allocation when disease-specific bundling strategies are being derived. [Copyright &y& Elsevier]

Introduction: Analysis of large complex survey databases is an important research tool for health services researchers in Surgery. Missing data elements are challenging as reasons they are missing are multi-factorial, especially variables with multiple categories such as race. We simulated missing data for race and analyzed the bias from five missing data methods used in predicting major amputation in patients with critical limb ischemia (CLI). Methods: Discharges with fully observed data containing lower extremity revascularization or major amputation and CLI were selected from the 2003-2007 Nationwide Inpatient Sample, a complex survey database (weighted N=684,057). Considering random and non-random missing data schemes, we simulated missing data for race to compare five missing data methods (complete case analysis (CCA), missing indicator variable (MIV), single imputation with mean frequencies, re-weighted estimating equations (RWEEs), and multiple imputation). Bias was determined by comparing mean regression coefficients estimated from 100 simulated datasets (B_miss) to those estimated from the fully observed dataset (B_full), with relative bias calculated as (B_full–B_miss/B_full)*100%. Results: Our results demonstrate that RWEEs produce the least biased and MIV the most biased coefficients. CCA, single imputation, and multiple imputation resulted in moderate bias. Sensitivity analysis demonstrated that optimal method choice depends on quantity and type of missing data encountered. Conclusions: Missing data is an important analytical topic in research with large databases. RWEEs are flexible and provided the least biased coefficients. The commonly used MIV method introduces the most bias and should be used with caution. We present empirical evidence to guide method selection for handling missing data. [ABSTRACT FROM AUTHOR]