Trends and predictors of inflation-adjusted costs in transcatheter and surgical aortic valve replacement in a nationally representative sample.

BACKGROUND: Transcatheter aortic valve replacement has become an accepted alternative to surgical aortic valve replacement. We examined the trends and predictors in inflation-adjusted costs of transcatheter aortic valve replacement and surgical aortic valve replacement. METHODS: National Inpatient Sample identified patients who underwent aortic valve replacement for severe aortic stenosis by International Classification of Diseases, Ninth and Tenth Revisions, codes. Hospitalization costs were inflation-adjusted using the Federal Reserve's consumer price index to reflect current valuation. Outcomes of interest were unadjusted trend in annual cost for each procedure and predictors of in-patient cost. Generalized linear models with a log link function identified predictors of adjusted costs. Interaction terms determined where cost predictors were different by operation type. RESULTS: Between 2011 and 2019, the mean annual inflation-adjusted cost of surgical aortic valve replacement increased from $62,853 to $63,743, in contrast to decreasing cost of transcatheter aortic valve replacement from $64,913 to $56,042 ($1,854 per year; P = .004). Significant independent predictors of patient-level cost included operation type (transcatheter aortic valve replacement associated with $9,625 increase; P < .001), incidence of in-hospital mortality ($28,836 increase; P < .001), elective status ($2,410 decrease; P < .001), Elixhauser Index ($995 increase; P < .001), and postoperative length of stay ($2,014 per day increase; P < .001). Compared to discharges with Medicare, discharges with private insurance and Medicaid paid $736 less (P = .004) and $1,863 less (P = .01), respectively. Increasing hospital volume was a significant predictor of decreasing patient level cost (P < .001). CONCLUSION: Annual cost of transcatheter aortic valve replacement has decreased significantly and has been a more cost-effective modality compared to surgical aortic valve replacement since 2017. Predictors of patient-level costs allow for mindful preparation of healthcare systems for aortic valve replacement.

The risks of failed nonoperative management of appendicitis in older adults.

BACKGROUND: The consequences of failed nonoperative management of appendicitis in older patients have not been described. METHODS: We used the 2004-2017 National Inpatient Sample to identify acute appendicitis patients managed nonoperatively (<65 years old: 32,469; ≥65 years old: 11,265). Outcomes included morbidity, length of stay (LOS), inpatient costs, and discharge to skilled facilities. Differences were estimated using propensity scores. RESULTS: For patients <65, nonoperative failure was associated with increased morbidity (7 â€‹% [95 â€‹% CI 6.9 â€‹%-8.1 â€‹%]), LOS (3 day [95 â€‹% CI 3-4]), costs ($9015 [95 â€‹% CI $8216- $9446]), and discharges to skilled facilities (1 â€‹% [95 â€‹% CI 0.9 â€‹%-1.6 â€‹%]) compared to successful nonoperative treatment. Patients ≥65 had differences in morbidity (14 â€‹% [95 â€‹% CI 13.6 â€‹%-16.2 â€‹%]), LOS (6 days [95 â€‹% CI 5-6]), costs ($15,964 [95 â€‹% CI $15,181- $17,708]), and discharges to skilled facilities (12 â€‹% [95 â€‹% CI: 10.0 â€‹%-13.3]) compared to nonoperative success. CONCLUSIONS: Nonoperative management of appendicitis should be approached cautiously for older adults.

Is nonoperative management of appendicitis safe and effective in multi-morbid patients?

BACKGROUND: The purpose of this study was to (1) compare post-treatment outcomes of operative and nonoperative management of acute appendicitis in multi-morbid patients and (2) evaluate the generalizability of prior clinical trials by determining whether outcomes differ in multi-morbid patients compared to the young and healthy patients who resemble prior clinical trial participants. METHODS: We conducted a retrospective cohort study using the National Inpatient Sample from 2004 to 2017. We included 368,537 patients with acute, uncomplicated appendicitis who were classified as having 0 or 2+ comorbidities. We compared inpatient morbidity, mortality, length of stay, and costs using propensity scores. Unmeasured confounding was addressed with probabilistic sensitivity analysis. RESULTS: Overall, 5% of patients without comorbidities were treated nonoperatively versus 20% of multi-morbid patients. Compared to surgery, nonoperative management was associated with a 3.5% decrease in complications (95% confidence interval 3%-4%) for multi-morbid patients, but there was no significant difference for patients without comorbidity. However, nonoperative management was associated with a 1.5% increase in mortality for multimorbid patients (95% confidence interval 1.3%-1.7%). Costs and length of stay were lower for all patients treated with surgery. Probabilistic sensitivity analysis showed that results were robust to the effects of unmeasured confounding. CONCLUSION: Our results raise concerns about the generalizability of clinical trials that compared nonoperative and operative management of appendicitis because (1) those trials enrolled mostly young and healthy patients, and (2) results in multi-morbid patients differ from outcomes in younger and healthier patients.

Association Between Coronavirus Disease 2019 Vaccination and Mortality After Major Operations.

OBJECTIVE: The objective of this study was to compare postoperative 90-day mortality between (1) fully vaccinated patients with COVID-19-positive and negative diagnosis, and (2) vaccinated and unvaccinated patients with COVID-19 positive diagnosis. BACKGROUND: Societal guidelines recommend postponing elective operations for at least 7 weeks in unvaccinated patients with preoperative coronavirus disease 2019 (COVID-19) infection. The role of vaccination in this infection-operation time risk is unclear. METHODS: We conducted a national US multicenter retrospective, matched cohort study spanning July 2021 to October 2022. Participants were included if they underwent a high-risk general, vascular, orthopedic, neurosurgery, or genitourinary surgery. All-cause mortality occurring within 90 days of the index operation was the primary outcome. Inverse probability treatment weighted propensity scores were used to adjust logistic regression models examining the independent and interactive associations between mortality, exposure status, and infection proximity. RESULTS: Of 3401 fully vaccinated patients in the 8-week preoperative period, 437 (12.9%) were COVID-19-positive. Unadjusted mortality rates were not significantly different between vaccinated patients with COVID-19 (22, 5.0%) and vaccinated patients without COVID-19 (99, 3.3%; P = 0.07). After inverse probability treatment weighted adjustment, mortality risk was not significantly different between vaccinated COVID-19-positive patients compared to vaccinated patients without COVID-19 (adjusted odds ratio = 1.38, 95% CI: 0.70, 2.72). The proximity of COVID-19 diagnosis to the index operation did not confer added mortality risk in either comparison cohort. CONCLUSIONS: Contrary to risks observed among unvaccinated patients, postoperative mortality does not differ between patients with and without COVID-19 when vaccinated against the severe acute respiratory syndrome coronavirus 2 virus and receiving a high-risk operation within 8 weeks of the diagnosis, regardless of operation timing relative to diagnosis.

Transfusion trigger after operations in high cardiac risk patients (TOP) trial protocol. Protocol for a multicenter randomized controlled transfusion strategy trial.

BACKGROUND: There is substantial uncertainty regarding the effects of restrictive postoperative transfusion among patients who have underlying cardiovascular disease. The TOP Trial's objective is to compare adverse outcomes between liberal and restrictive transfusion strategies in patients undergoing vascular and general surgery operations, and with a high risk of postoperative cardiac events. METHODS: A two-arm, single-blinded, randomized controlled superiority trial will be used across 15 Veterans Affairs hospitals with expected enrollment of 1520 participants. Postoperative transfusions in the liberal arm commence when Hb is <10 g/ dL and continue until Hb is greater than or equal to 10 g/dL. In the restrictive arm, transfusions begin when Hb is <7 g/dL and continue until Hb is greater than or equal to 7 g/dL. Study duration is estimated to be 5 years including a 3-month start-up period and 4 years of recruitment. Each randomized participant will be followed for 90 days after randomization with a mortality assessment at 1 year. RESULTS: The primary outcome is a composite endpoint of all-cause mortality, myocardial infarction (MI), coronary revascularization, acute renal failure, or stroke occurring up to 90-days after randomization. Events rates will be compared between restrictive and liberal transfusion groups. CONCLUSIONS: The TOP Trial is uniquely positioned to provide high quality evidence comparing transfusion strategies among patients with high cardiac risk. Results will clarify the effect of postoperative transfusion strategies on adverse outcomes and inform postoperative management algorithms. TRIAL REGISTRATION: http://clinicaltrials.gov identifier: NCT03229941.

Practical Guide to Designing a Clinical Trial in Surgery.

This Guide to Statistics and Methods outlines the key elements that need to be considered during the design phase of a surgical clinical trial.

Comparison of Longitudinal Skeletal Thigh Muscle Findings With Magnetic Resonance Imaging in Patients With Peripheral Artery Disease With-Versus-Without Diabetes Mellitus.

The aim of this secondary analysis of ELIMIT (The Effect of Lipid Modification on Peripheral Artery Disease after Endovascular Intervention Trial) was to determine longitudinal changes over 24 months in skeletal thigh muscle volumes and individual muscle compartments in patients with peripheral artery disease (PAD) with and without diabetes. A total of 48 patients with available magnetic resonance imaging of the distal superficial femoral artery at baseline and 2 years were included in this analysis. Muscle volumes and superficial femoral artery wall, lumen, and total vessel volumes were quantified. Intrareader reproducibility of muscle tracings was assessed with the intraclass correlation coefficient using a 2-way model. Baseline characteristics were similar between patients with PAD with and without diabetes, except for smoking history (p = 0.049), cholesterol levels (p <0.050), and calf walking pain (p = 0.049). Interobserver reproducibility of the muscle volume tracings was excellent for all muscle groups (all intraclass correlation coefficients >0.86, confidence interval 0.69 to 0.94). Total muscle and total leg volumes increased significantly between baseline and 24 months among patients with PAD without diabetes (31 ± 6.4 cm3 vs 32 ± 7.0 cm3, p <0.001; 18 ± 4.4 cm3 vs 19 ± 4.8 cm3, p = 0.045), whereas there was no change in patients with PAD and diabetes. Total muscle volume was inversely associated with age and body mass index in patients with PAD both with and without diabetes (p <0.05). In conclusion, magnetic resonance imaging-quantified thigh muscle volumes are highly reproducible and may be of interest in assessing PAD patients with and without diabetes.

Timing of a Major Operative Intervention After a Positive COVID-19 Test Affects Postoperative Mortality: Results From a Nationwide, Procedure-matched Analysis.

BACKGROUND: Studies indicate that coronavirus disease 2019 (COVID-19) infection before or soon after operations increases mortality, but they do not comment on the appropriate timing for interventions after diagnosis. OBJECTIVE: We sought to determine what the safest time would be for COVID-19 diagnosed patients to undergo major operative interventions. METHODS: High-risk operations, between January 2020 and May 2021, were identified from the Veterans Affairs COVID-19 Shared Data Resource. Current Procedural Terminology (CPT) codes were used to exact match COVID-19 positive cases (n=938) to negative controls (n=7235). Time effects were calculated as a continuous variable and then grouped into 2-week intervals. The primary outcome was 90-day, all-cause postoperative mortality. RESULTS: Ninety-day mortality in cases and controls was similar when the operation was performed within 9 weeks or longer after a positive test; but significantly higher in cases versus controls when the operation was performed within 7 to 8 weeks (12.3% vs 4.9%), 5 to 6 weeks (10.3% vs 3.3%), 3 to 4 weeks (19.6% vs 6.7%), and 1 to 2 weeks (24.7% vs 7.4%) from diagnosis. Among patients who underwent surgery within 8 weeks from diagnosis, 90-day mortality was 16.6% for cases versus 5.8% for the controls ( P <0.001). In this cohort, we assessed interaction between case status and any symptom ( P =0.93), and case status and either respiratory symptoms or fever ( P =0.29), neither of which were significant statistically. CONCLUSIONS: Patients undergoing major operations within 8 weeks after a positive test have substantially higher postoperative 90-day mortality than CPT-matched controls without a COVID-19 diagnosis, regardless of presenting symptoms.

Factors associated with preference of choice of aortic aneurysm repair in the PReference for Open Versus Endovascular repair of AAA (PROVE-AAA) study.

OBJECTIVE: Patients can choose between open repair and endovascular repair (EVAR) of abdominal aortic aneurysm (AAA). However, the factors associated with patient preference for one repair type over another are not well-characterized. Here we assess the factors associated with preference of choice for open or endovascular AAA repair among veterans exposed to a decision aid to help with choosing surgical treatment. METHODS: Across 12 Veterans Affairs hospitals, veterans received a decision aid covering domains including patient information sources and understanding preference. Veterans were then given a series of surveys at different timepoints examining their preferences for open versus endovascular AAA repair. Questions from the preference survey were used in analyses of patient preference. Results were analyzed using χ2 tests. A logistic regression analysis was performed to assess factors associated with preference for open repair or preference for EVAR. RESULTS: A total of 126 veterans received a decision aid informing them of their treatment choices, after which 121 completed all preference survey questions; five veterans completed only part of the instruments. Overall, veterans who preferred open repair were typically younger (70 years vs 73 years; P = .02), with similar rates of common comorbidities (coronary disease 16% vs 28%; P = .21), and similar aneurysms compared with those who preferred EVAR (6.0 cm vs 5.7 cm; P = .50). Veterans in both preference categories (28% of veterans preferring EVAR, 48% of veterans preferring open repair) reported taking their doctor's advice as the top box response for the single most important factor influencing their decision. When comparing the tradeoff between less invasive surgery and higher risk of long-term complications, more than one-half of veterans preferring EVAR reported invasiveness as more important compared with approximately 1 in 10 of those preferring open repair (53% vs 12%; P < .001). Shorter recovery was an important factor for the EVAR group (74%) and not important in the open repair group (76%) (P = .5). In multivariable analyses, valuing a short hospital stay (odds ratio, 12.4; 95% confidence interval, 1.13-135.70) and valuing a shorter recovery (odds ratio, 15.72; 95% confidence interval, 1.03-240.20) were associated with a greater odds of preference for EVAR, whereas finding these characteristics not important was associated with a greater odds of preference for open repair. CONCLUSIONS: When faced with the decision of open repair versus EVAR, veterans who valued a shorter hospital stay and a shorter recovery were more likely to prefer EVAR, whereas those more concerned about long-term complications preferred an open repair. Veterans typically value the advice of their surgeon over their own beliefs and preferences. These findings need to be considered by surgeons as they guide their patients to a shared decision.

Racial and ethnic disparities in abdominal aortic aneurysm evaluation and treatment rates in Texas.

BACKGROUND: Screening identifies intact abdominal aortic aneurysms (iAAAs) before progression to ruptured AAAs (rAAAs). However, screening efforts have been limited by the low overall diagnostic yield and unequal screening among minority populations. The goal of the present study was to identify equitable AAA screening strategies for both majority and minority populations. METHODS: We performed epidemiologic and geospatial analyses of inpatient and outpatient procedures for iAAAs and rAAAs at Texas hospitals from 2006 through 2014 at all nonfederal hospitals and clinics in Texas. The data were aggregated by area (metropolitan statistical area vs rural region) and then supplemented by six additional data sources to estimate the AAA repair incidence rates, rates of AAA-related clinic and ultrasound visits, travel distance to providers, and the location and number of unrecognized AAAs. RESULTS: Most AAA repairs had occurred among men aged 65 to 84 years and categorized as White in large metropolitan areas. The area procedure rates for rAAAs and iAAAs were strongly correlated (R2 = 0.47). Two other variables-the proportions of persons categorized as White and those aged ≥65 years in a region-identified subgroups within the majority population with a high risk of iAAAs (R2 = 0.46). Lower rates of clinic visits and AAA ultrasound scans were seen among persons categorized as Black. Several areas with disproportionately higher rAAA/iAAA repair ratios were found, mainly affecting persons categorized as Black. CONCLUSIONS: Multiple focused AAA screening strategies could be required to address the disproportionately lower AAA identification among persons categorized as Black.

Treatment of Early Deep Wound Infections after Arterial Reconstructions: A Meta-Analysis and Survey.

BACKGROUND: Peripheral vascular graft infections, a serious concern after open lower extremity interventions, are treated using multiple strategies. Yet, there is no consensus on the optimal treatment. This study summarizes the literature and compares aggregate effect sizes between graft preservation with antibiotic beads and total graft excision. METHODS: Manuscripts published between 1972 and 2019 were systematically queried using Ovid Medline and PubMed. Studies were included if they described early (≤4 months of the index procedure) infection-related outcomes after extracavitary and infrainguinal arterial graft infections that were managed with antibiotic-loaded beads or total excisions. Outcomes assessed included the prevalence of graft preservation failure, reinfection, and major amputation. To examine current preferences on this subject, a voluntary, anonymous survey was administered to practicing members of the Society for Clinical Vascular Surgery. RESULTS: Six graft preservation studies (n = 147 patients) were included in the meta-analysis, based on PRISMA guidelines. The meta-analytic pooled proportion of patients with: (1) graft preservation failure was 0.09 (95% CI: 0.00, 0.46, I2 = 88.8%), (2) reinfection was 0.04 (95% CI: 0.00, 0.18, I2 = 79.7%), and (3) major amputation was 0.00 (95% CI: 0.00, 0.04, I2 = 0%). Five studies addressing total excisions were identified via the systematic review however, their combined sample size (n = 28 patients) impeded use of a meta-analysis. Ninety (19%) licensed surgeons participated in the survey. In a hemodynamically stable, nonseptic patient, 67% (60) of respondents routinely excise the graft, while 31% (28) prefer preservation. CONCLUSIONS: Study design and patient characteristic-related heterogeneity limited our ability to generate robust, clinical evidence-level outcome estimates. A prospective study is necessary to definitively establish the efficacy of antibiotic beads in the treatment and preservation of vascular graft infections.

Outcomes after Endovascular Stent Placement for Long-Segment Superficial Femoral Artery Lesions.

BACKGROUND: Endovascular intervention is commonly pursued as first-line management of symptomatic, long-segment superficial femoral artery (SFA) disease. The relative effectiveness and comparative long-term outcomes among bare metal stents (BMS), covered stents (CS), and drug-eluting stents (DES) for long-segment SFA lesions remain uncertain. METHODS: A retrospective cohort study identified patients with symptomatic SFA lesions measuring at least 15 cm in length who successfully received an endovascular stent (BMS, CS, or DES). The outcomes were patency, patient presentation upon stent occlusion, amputation-free survival (AFS), and all-cause mortality. Proportional hazards regressions and a multinomial logistic regression model were used to control for significant confounders. RESULTS: A total of 226 procedures were analyzed (BMS: 95 [42%]; CS: 74 [33%]; DES: 57 [25%]). There were no significant differences among the 3 stent types with respect to age, prevalence of either diabetes or end-stage renal disease, or smoking history. The median length of the SFA lesion varied across the cohorts (BMS: 28 cm [interquartile range, IQR 20-30]; CS: 26 cm [IQR 20-30]; DES: 20 cm [IQR 16-25]; P = 0.002). The unadjusted primary patency of BMS at 12, 24, and 48 month following index stent placement was 57%, 47%, and 44%, respectively. This is compared to 62%, 49%, and 42% for CS, and 81%, 66%, and 53% for DES, respectively (log-rank P = 0.044). In adjusted models, however, there were no significant differences in primary patency among the stent types. Compared to CS however, DES was associated with improved primary-assisted patency (hazard ratio [HR] for patency loss: 0.35, P = 0.008) and secondary patency (HR: 0.32, P = 0.011). Across the entire follow-up period, stent occlusions occurred in 38 (40%) BMS cases, 42 (57%) CS, and 11 (19%) DES (P < 0.001). Of these, acute limb ischemia (ALI) occurred in 2 (5%) BMS cases, 14 (33%) CS, and 1 (9%) DES (P = 0.010). After adjustment, the relative risk of presenting with ALI as opposed to claudication was 27 times greater among patients re-presenting with occluded CS compared to BMS (P = 0.020). There were no significant differences in AFS or all-cause mortality across the 3 cohorts. CONCLUSIONS: For long-segment SFA lesions, DES is associated with improved primary-assisted and secondary patency over long-term follow-up. In the event of stent occlusion, CS is associated with an increased risk of ALI.

Wound Complications and Reoperations after Transtibial Amputation of the Leg.

BACKGROUND: Transtibial amputations (TTAs) of the leg have been associated with high rates of wound complications. We assessed outcomes of TTAs to determine if bundled interventions implemented at our hospital had an impact on lowering wound complications, including surgical site infections. METHODS: We assessed the impact of a surgical site infection prevention bundle (negative-pressure wound therapy, minimizing the use of staples, and a decontamination protocol for methicillin-resistant Staphylococcus aureus) on 90-day wound complications. The year of implementation of the prevention bundle was excluded, and the pre-eras and posteras were defined as the four-year period before and after implementation. The study sample consisted of a single-center cohort, with TTA cases identified using operating room scheduling software. RESULTS: A total of 182 TTAs were performed: 110 in the pre-era and 72 in the postera. The wound complication rate decreased from 22 to 17% despite fewer two-stage operations, less imaging to identify peripheral artery disease, and an increased proportion of patients with end-stage renal disease. Wound complications and revision to a higher level of amputation were more associated with indication (especially no-option peripheral artery disease with ischemic rest pains) than with any particular aspect of surgical technique. The use of drains was associated with reoperations but not higher level revision. CONCLUSIONS: Higher rates of wound complications and revision to a higher level of amputations should be expected among patients with no-option peripheral artery disease with ischemic rest pains undergoing TTAs. Drains should be avoided.

Long-term outcomes of lower extremity graft preservation using antibiotic beads in patients with early deep wound infections after major arterial reconstructions.

OBJECTIVE: Bypass graft preservation with wound sterilization using serial antibiotic bead exchange has been described in patients presenting with deep wound infections after extremity bypass. The long-term benefits of this approach remain poorly understood. We examined whether graft preservation and wound sterilization with antibiotic beads affect amputation rates and patient survival. METHODS: Patients who underwent operations for aortoiliac or infrainguinal aneurysmal or occlusive arterial disease were retrospectively analyzed. The Infection group included those with patent vascular grafts who developed Szilagyi class II or III deep wound infections within 90 days of index reconstruction and had no evidence of anastomotic or arterial bleeding. All patients in the infection group were managed with graft preservation using serial antibiotic bead exchange every 3 to 5 days until wound cultures became negative. This group was compared with a contemporary group of controls who underwent similar interventions but did not develop wound infections postoperatively. The primary outcome was amputation-free survival, defined as survival without major amputation. Secondary outcomes included major amputations and the occurrence of anastomotic pseudoaneurysms necessitating repair. Inverse propensity score weighting was used for risk adjustment between the groups. RESULTS: Over an 8-year period, we treated 701 patients (infection, 68; controls, 633). Compared with controls, patients in the infection group had a higher body mass index (mean, 28.5 vs 26.3, P = .002) and more prosthetic conduits placed during the index reconstruction. Amputation-free survival for the infection vs the control group was 78 vs 76% at 2 years, 61 vs 66% at 4 years, and 51 vs 57% at 6 years postoperatively (log-rank test, P = .516). Freedom from major amputation for the infection vs the control group was 82 vs 86% at 2 years, 80 vs 82% at 4 years, and 80 vs 76% at 6 years postoperatively (log-rank test, P = .568). In the risk-adjusted model, the presence of treated infection did not affect amputation-free survival (hazard ratio, 0.82; P = .440) or major amputation (hazard ratio, 1.02; P = .949). Anastomotic pseudoaneurysms occurred only in the Infection group (4.4%; P = .001), and were treated with interposition grafts without complications. CONCLUSIONS: Bypass graft preservation with wound sterilization using serial antibiotic bead exchange is associated with excellent limb salvage and survival rates, similar to those of noninfected wounds. With the use of this preservation strategy, close follow-up for timely detection of anastomotic pseudoaneurysms is recommended.

The Ever-Humbling Challenge of Peripheral Artery Disease Treatment Seen Across the Sexes.

See Article Ramkumar et al.

Effect of Postoperative Permissive Anemia and Cardiovascular Risk Status on Outcomes After Major General and Vascular Surgery Operative Interventions.

OBJECTIVES: To determine the effect of postoperative permissive anemia and high cardiovascular risk on postoperative outcomes. METHODS: The Veterans Affairs Surgical Quality Improvement Program and Corporate Data Warehouse databases were queried for patients who underwent major vascular or general surgery operations. The status of cardiovascular risk was assessed by calculating the Revised Cardiac Risk Index. Primary endpoint was a composite of mortality, myocardial infarction, acute renal failure, coronary revascularization, or stroke within 90 days postoperatively. RESULTS: We analyzed 142,510 procedures performed from 2000 to 2015. Postoperative anemia was the strongest independent predictor of the primary endpoint whose odds increased by 43% for every g/dL drop in postoperative nadir Hb [95% confidence interval (95% CI): 41-45]. Cardiac risk status as described by the RCRI also independently predicted the primary endpoint, with an additive effect particularly evident at postoperative nadir Hb values below 10 gm/dL. Postoperative anemia, after age, was the second strongest independent predictor of long-term (12 years) mortality (hazard ratio: 1.18, 95% CI: 1.17-1.19). CONCLUSION: Postoperative anemia is strongly associated with postoperative ischemic events, 90-day mortality, and long-term mortality. Restrictive transfusion should be used cautiously after major general and vascular operations, particularly in patients at a high cardiovascular risk.

Delayed gratification and adherence to exercise among patients with claudication.

Few studies have explicitly identified factors that explain an individual's willingness to engage in community-based exercise for claudication. Identifying the unique characteristics of those inclined toward physical activity would inform interventions that encourage walking. We examined the utility of behavioral economics-related concepts in understanding walking among Veterans with claudication. Patients who received care at the Michael E. DeBakey Veterans Affairs Medical Center in Houston, Texas, were surveyed on symptom severity, behavioral economics, stress, and depression. The primary outcome was a binary variable measuring current walking for exercise and defined as walking for at least 30 minutes every day. Multivariable logistic regression models were used to identify variables, both clinically and statistically significant, at a p-value < 0.05. Between April 2017 and March 2018, we received 148 (30%) responses. A total of 35% (n = 51) of respondents indicated that they walked recreationally for exercise compared to 65% (n = 94) who did not. Characteristics that were significantly associated with walking included regularly saving money (adjusted odds ratio (aOR) = 10.7, p = 0.001), seeking complex problem-solving (aOR = 0.12, p = 0.002), and severe symptoms (aOR = 0.24, p = 0.017). Individuals describing a preference for the future rather than immediate benefit also reported currently walking for exercise. Defining the characteristics of those who exercise may help inform strategies designed to increase walking among those who do not adhere to recommendations.