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Limiting the duration of antimicrobial treatment constitutes a potential strategy to reduce the risk of antimicrobial resistance among children with acute otitis media.We assigned 520 children, 6 to 23 months of age, with acute otitis media to receive amoxicillin-clavulanate either for a standard duration of 10 days or for a reduced duration of 5 days followed by placebo for 5 days. We measured rates of clinical response (in a systematic fashion, on the basis of signs and symptomatic response), recurrence, and nasopharyngeal colonization, and we analyzed episode outcomes using a noninferiority approach. Symptom scores ranged from 0 to 14, with higher numbers indicating more severe symptoms.Children who were treated with amoxicillin-clavulanate for 5 days were more likely than those who were treated for 10 days to have clinical failure (77 of 229 children [34%] vs. 39 of 238 [16%]; difference, 17 percentage points [based on unrounded data]; 95% confidence interval, 9 to 25). The mean symptom scores over the period from day 6 to day 14 were 1.61 in the 5-day group and 1.34 in the 10-day group (P=0.07); the mean scores at the day-12-to-14 assessment were 1.89 versus 1.20 (P=0.001). The percentage of children whose symptom scores decreased more than 50% (indicating less severe symptoms) from baseline to the end of treatment was lower in the 5-day group than in the 10-day group (181 of 227 children [80%] vs. 211 of 233 [91%], P=0.003). We found no significant between-group differences in rates of recurrence, adverse events, or nasopharyngeal colonization with penicillin-nonsusceptible pathogens. Clinical-failure rates were greater among children who had been exposed to three or more children for 10 or more hours per week than among those with less exposure (P=0.02) and were also greater among children with infection in both ears than among those with infection in one ear (P0.001).Among children 6 to 23 months of age with acute otitis media, reduced-duration antimicrobial treatment resulted in less favorable outcomes than standard-duration treatment; in addition, neither the rate of adverse events nor the rate of emergence of antimicrobial resistance was lower with the shorter regimen. (Funded by the National Institute of Allergy and Infectious Diseases and the National Center for Research Resources; ClinicalTrials.gov number, NCT01511107 .).

Introduction We sought to understand the effects of Coronavirus-2019 (COVID-19) on vascular surgery practices as related to the VASCON scale. Methods All members of the Vascular and Endovascular Surgery Society (VESS) were surveyed on the effects of COVID-19 in their practices, educational programs, and self-reported grading of their surgical acuity level using the VASCON scale. Results Total response rate was 28% (206/731). Most respondents (99.5%) reported an effect of COVID-19 on their practice, and most were VASCON3 or lower level. Most reported a decrease in clinic referrals, inpatient/ ER consults, and case volume (p

Background: Literature on postoperative outcomes following aortic surgery for aortic graft infection (AGI) is limited by relatively small sample sizes, resulting in lack of national benchmarks for quality of care. We report in-hospital outcomes following abdominal aortic surgery for AGI and identify factors associated with postoperative complications using the Nationwide Inpatient Sample (NIS) database. Methods: Patients who underwent aortic graft resection for AGI were identified from the 2002 to 2008 NIS database, a multicenter database capturing 20% of all US admissions. Multivariable logistic regression analyses were performed. Results: Among 394 patients (men: 73.4%) who underwent abdominal aortic surgery for AGI, 53% of the admissions were emergent/urgent. A significant trend for decreasing number of abdominal aortic surgery for AGIs per year was observed (Pearson r correlation: −.96; P = .0006). Over the same time span, a significant correlation was also seen with decrease in open and increase in endovascular aortic aneurysm repairs in the NIS database. In-hospital rates of overall postoperative morbidity and mortality were 68.3% and 19.8%, respectively. In-hospital rates of postoperative respiratory failure, renal failure, and cardiac arrest were 35.5%, 14.2%, and 8.9%, respectively. Median length of stay was 26 days, with median hospital charges being US$184 162. On multivariable analysis, increase in age per year (odds ratio [OR] 1.07; 95% confidence interval [CI]: 1.03-1.12) was independently associated with postoperative morbidity, while higher hospital volume for this procedure was protective (OR: 0.71; 95% CI: 0.56-0.89). No preoperative factors were independently associated with postoperative mortality. Conclusion: Incidence of abdominal aortic surgery for AGI has progressively declined over the span of our study in association with decreased open and increased endovascular aortic aneurysm repairs. Aortic surgery for AGI is associated with very high morbidity and mortality rates along with prolonged lengths of stay and elevated hospital charges. The outcomes of operations for AGI are better in younger patients and higher volume hospitals.

OBJECTIVE: Symptomatic peripheral arterial disease (PAD) impairs walking, but data on the impact of PAD on community mobility is limited. Life-space mobility measures the distance, frequency, and assistance needed as older adults move through geographic areas extending from their bedroom (life-space mobility score: 0) to beyond their town (life-space mobility score: 120). We evaluated the association of PAD with longitudinal life-space mobility trajectory. METHODS: Participants were part of the University of Alabama at Birmingham (UAB) Study of Aging, a longitudinal study of community-dwelling older adults who were followed from 2001–2009. We limited our analysis to those who survived at least 6 months (N=981). PAD was based on self-report with verification by physician/hospital records. Our primary outcome was life-space mobility score assessed every six-months. A multilevel change model (mixed model) was used to determine the association between PAD and life-space mobility trajectory over a median 7.9 years of follow-up. RESULTS: Participants had a mean age of 75.7 (SD 6.7), 50.5% were female, and 50.4% were African American. PAD prevalence was 10.1%, and 57.1% of participants with PAD died. In participants with both PAD and life-space restriction, defined as life-space mobility score

Rapid and objective preoperative assessment of patients undergoing carotid endarterectomy (CEA) remains problematic. Preoperative variables correlate with increased morbidity and mortality, yet no easily implemented tool exists to stratify patients. We determined the relationship between our fully implemented frailty-based bedside Risk Analysis Index (RAI) and complications after CEA.Patients undergoing CEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database from 2005 to 2011 were included. Variables of frailty RAI were matched to preoperative NSQIP variables, and outcomes including stroke, mortality, myocardial infarction (MI), and length of stay were analyzed. We further analyzed patients who were symptomatic and asymptomatic before CEA.With use of the NSQIP database, 44,832 patients undergoing CEA were analyzed (17,696 [39.5%] symptomatic; 27,136 [60.5%] asymptomatic). Increasing frailty RAI score correlated with increasing stroke, death, and MI (P.0001) as well as with length of stay. RAI demonstrated increasing risk of stroke and death on the basis of risk stratification (low risk [0-10], 2.1%; high risk [10], 5.0%). Among patients undergoing CEA, 88% scored low (10) on the RAI. In symptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 2.9%, whereas if the RAI score is 11 to 15, it is 5.0%; 16 to 20, 6.9%; and21, 8.6%. In asymptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 1.6%, whereas if the RAI score is 11 to 15, it is 2.9%; 16 to 20, 5.2%; and21, 6.2%.Frailty is a predictor of increased stroke, mortality, MI, and length of stay after CEA. An easily implemented RAI holds the potential to identify a limited subset of patients who are at higher risk for postoperative complications and may not benefit from CEA.

As the US population ages, the number of operations performed on elderly patients will likely increase. Frailty predicts postoperative mortality and morbidity more than age alone, thus presenting opportunities to identify the highest-risk surgical patients and improve their outcomes.To examine the effect of the Frailty Screening Initiative (FSI) on mortality and complications by comparing the surgical outcomes of a cohort of surgical patients treated before and after implementation of the FSI.This single-site, facility-wide, prospective cohort quality improvement project studied all 9153 patients from a level 1b Veterans Affairs medical center who presented for major, elective, noncardiac surgery from October 1, 2007, to July 1, 2014.Assessment of preoperative frailty in all patients scheduled for elective surgery began in July 2011. Frailty was assessed with the Risk Analysis Index (RAI), and the records of all frail patients (RAI score, ≥21) were flagged for administrative review by the chief of surgery (or designee) before the scheduled operation. On the basis of this review, clinicians from surgery, anesthesia, critical care, and palliative care were notified of the patient's frailty and associated surgical risks; if indicated, perioperative plans were modified based on team input.Postoperative mortality at 30, 180, and 365 days.From October 1, 2007, to July 1, 2014, a total of 9153 patients underwent surgery (mean [SD] age, 60.3 [13.5] years; female, 653 [7.1%]; and white, 7096 [79.8%]). Overall 30-day mortality decreased from 1.6% (84 of 5275 patients) to 0.7% (26 of 3878 patients, P .001) after FSI implementation. Improvement was greatest among frail patients (12.2% [24 of 197 patients] to 3.8% [16 of 424 patients], P .001), although mortality rates also decreased among the robust patients (1.2% [60 of 5078 patients] to 0.3% [10 of 3454 patients], P .001). The magnitude of improvement among frail patients increased at 180 (23.9% [47 of 197 patients] to 7.7% [30 of 389 patients], P .001) and 365 days (34.5% [68 of 197 patients] to 11.7% [36 of 309 patients], P .001). Multivariable models revealed improved survival after FSI implementation, controlling for age, frailty, and predicted mortality (adjusted odds ratio for 180-day survival, 2.87; 95% CI, 1.98-4.16).Implementation of the FSI was associated with reduced mortality, suggesting the feasibility of widespread screening of patients preoperatively to identify frailty and the efficacy of system-level initiatives aimed at improving their surgical outcomes. Additional investigation is required to establish a causal connection.

Objective The objective of this study was to assess the impact of preoperative anemia (hematocrit Background Preoperative anemia is associated with adverse outcomes after cardiac surgery, but its association with postoperative outcomes after open and endovascular procedures is not well established. Elderly patients have a decreased tolerance to anemia and are at high risk for complications after vascular procedures. Methods Patients (N = 31,857) were identified from the American College of Surgeons' 2007-2009 National Surgical Quality Improvement Program-a prospective, multicenter (>250) database maintained across the United States. The primary and secondary outcomes of interest were 30-day mortality and a composite end point of death or cardiac event (cardiac arrest or myocardial infarction), respectively. Results Forty-seven percent of the study population was anemic. Anemic patients had a postoperative mortality and cardiac event rate of 2.4% and 2.3% in contrast to the 1.2% and 1.2%, respectively, in patients with hematocrit within the normal range (P Conclusions The presence and degree of preoperative anemia are independently associated with 30-day death and adverse cardiac events in patients 65 years or older undergoing elective open and endovascular procedures. Identification and treatment of anemia should be important components of preoperative care for patients undergoing vascular operations.

Open infrarenal abdominal aortic aneurysm (oAAA) repair is associated with significant morbidity and mortality. Although there has been a shift toward endovascular repair, many patients continue to undergo an open repair due to anatomic considerations. Tools currently existing for estimation of periprocedural risk in patients undergoing open aortic surgery have certain limitations. The objective of this study was to develop a risk index to estimate the risk of 30-day perioperative mortality after elective oAAA repair.Patients who underwent elective oAAA repair (n = 2845) were identified from the American College of Surgeons' 2007 to 2009 National Surgical Quality Improvement Program (NSQIP), a prospective database maintained at250 centers. Univariable and multivariable analyses were performed to evaluate risk factors associated with 30-day mortality after oAAA repair and a risk index was developed.The 30-day mortality after oAAA repair was 3.3%. Multivariable analysis identified six preoperative predictors of mortality, and a risk index was created by assigning weighted points to each predictor using the β-coefficients from the regression analysis. The predictors included dyspnea (at rest: 8 points; on moderate exertion: 2 points; none: 0 points), history of peripheral arterial disease requiring revascularization or amputation (3 points), age65 years (3 points), preoperative creatinine1.5 mg/dL (2 points), female gender (2 points), and platelets150,000/mm(3) or350,000/mm(3) (2 points). Patients were classified as low (7%), intermediate (7%-15%), and high (15%) risk for 30-day mortality based on a total point score of8, 8 to 11, and11, respectively. There were 2508 patients (88.2%) patients in the low-risk category, 278 (9.8%) in the intermediate-risk category, and 59 (2.1%) in the high-risk category.This risk index has excellent predictive ability for mortality after oAAA repair and awaits validation in subsequent studies. It is anticipated to aid patients and surgeons in informed patient consent, preoperative risk assessment, and optimization.

ObjectiveRecent single-center reports demonstrate a high (up to 10%) incidence of postoperative venous thromboembolism (VTE) after major vascular surgery. Moreover, vascular patients rarely receive prolonged prophylaxis despite evidence that it reduces thromboembolic events after discharge. This study used a national, prospective, multicenter database to define the incidence of overall and postdischarge VTE after major vascular operations and assess risk factors associated with VTE development.MethodsPatients with VTE who underwent elective vascular procedures (n = 45,548) were identified from the 2007-2009 National Surgical Quality Improvement Program (NSQIP) database. The vascular procedures included carotid endarterectomy (CEA; n = 20,785), open thoracoabdominal aortic aneurysm (TAAA) repair (n = 361), thoracic endovascular aortic repair (TEVAR; n = 732), open abdominal aortic (OAA) surgery (n = 6195), endovascular aneurysm repair (EVAR; n = 7361), and infrainguinal bypass graft (BPG; n = 10,114). Univariable and multivariable analyses were performed to ascertain risk factors associated with VTE.ResultsVTE was diagnosed in 187 patients (1.3 %) who underwent aortic surgery, with TAAA repair having the highest rate of VTE (4.2%), followed by TEVAR (2.2%), OAA surgery (1.7%), and EVAR (0.7%). In this subgroup, pulmonary embolisms (PE) were diagnosed in 52 (0.4%) and deep venous thrombosis (DVT) in 144 (1%). VTE rates were 1.0% and 0.2% for patients who underwent a BPG or CEA, respectively. Forty-one percent of all VTEs were diagnosed after discharge. The median (interquartile range) number of days from surgery to PE and DVT were 10 (5-15) and 10 (4-18), respectively. On multivariable analyses, type of surgical procedure, totally dependent functional status, disseminated cancer, postoperative organ space infection, postoperative cerebrovascular accident, failure to wean from ventilator ≤48 hours, and return to the operating room were significantly associated with development of VTE. In those experiencing a DVT or PE, overall mortality increased from 1.5% to 6.2% and from 1.5% to 5.7% respectively (P < .05 for both).ConclusionsPostoperative VTE is associated with the type of vascular procedure and is highest after operations in the chest and abdomen/pelvis. About 40% of VTE events in elective vascular surgery patients were diagnosed after discharge, and the presence of VTE was associated with a quadrupled mortality rate. Future studies should evaluate the benefit of DVT screening and postdischarge VTE prophylaxis in high-risk patients.

ObjectivesMultiple randomised trials have demonstrated lower perioperative mortality after endovascular aneurysm repair (EVAR) compared to open surgical repair for infrarenal abdominal aortic aneurysms (AAAs). However, in these trials the mortality advantage for EVAR is being lost within 2 years of repair and the patients evaluated are relatively older with no study specifically comparing EVAR and open repair for patients younger than 60 years of age.DesignA retrospective analysis of prospectively collected data.Materials and methodsPatients younger than 60 years of age who underwent EVAR and open surgical repair for elective infrarenal AAA were identified from the 2007–09 National Surgical Quality Improvement Program (NSQIP) – a prospective database maintained at 237 centres across the United States. Univariate and multivariate analyses were performed.ResultsOf the 651 patients, 369 (56.7%) underwent EVAR and 282 (43.3%) underwent open repair. Thirty-day mortality for EVAR and open repair were 1.1% and 0.4%, respectively. This was not significantly different on univariate (P = 0.22) as well as multivariate (P = 0.69) analysis after controlling for other co-morbidities. On multivariate analysis, body mass index, history of stroke and bleeding disorder prior to surgery were associated with a higher 30-day mortality after AAA repair (combined open and EVAR).ConclusionsThese contemporary results demonstrate that the 30-day mortality rate after open repair is similar to that after EVAR in patients younger than 60 years with infrarenal AAA.

Background— Perioperative myocardial infarction or cardiac arrest is associated with significant morbidity and mortality. The Revised Cardiac Risk Index is currently the most commonly used cardiac risk stratification tool; however, it has several limitations, one of which is its relatively low discriminative ability. The objective of the present study was to develop and validate a predictive cardiac risk calculator. Methods and Results— Patients who underwent surgery were identified from the American College of Surgeons' 2007 National Surgical Quality Improvement Program database, a multicenter (>250 hospitals) prospective database. Of the 211 410 patients, 1371 (0.65%) developed perioperative myocardial infarction or cardiac arrest. On multivariate logistic regression analysis, 5 predictors of perioperative myocardial infarction or cardiac arrest were identified: type of surgery, dependent functional status, abnormal creatinine, American Society of Anesthesiologists' class, and increasing age. The risk model based on the 2007 data set was subsequently validated on the 2008 data set (n=257 385). The model performance was very similar between the 2007 and 2008 data sets, with C statistics (also known as area under the receiver operating characteristic curve) of 0.884 and 0.874, respectively. Application of the Revised Cardiac Risk Index to the 2008 National Surgical Quality Improvement Program data set yielded a relatively lower C statistic (0.747). The risk model was used to develop an interactive risk calculator. Conclusions— The cardiac risk calculator provides a risk estimate of perioperative myocardial infarction or cardiac arrest and is anticipated to simplify the informed consent process. Its predictive performance surpasses that of the Revised Cardiac Risk Index.

Background Previously, Midwestern veteran patients had limited bariatric surgery access because they lived long distances from a bariatric surgery center (BSC). The creation and outcomes of a network to increase bariatric surgery access and patient satisfaction with teleconsultation are discussed. Methods Several referring Midwestern Veterans Affairs Medical Centers (VAMCs) performed pre- and postoperative management and were linked by teleconferencing and a computerized patient record system to a single BSC. Results Twenty-eight high-risk patients (older, male) residing an average distance of 324.5 miles from the BSC underwent gastric bypass. Eighty-two percent used teleconferencing for the initial surgical consultation with excellent patient satisfaction saving at least 19,000 miles and 69 travel days. Surgical outcomes were equivalent and follow-up was excellent (96.6%) compared with non-Veterans Affairs patients. Conclusions A cooperative network using teleconference and computerized records facilitated bariatric surgery in high-risk, remotely located VA patients with high patient satisfaction and without compromising surgical outcomes.

ObjectivesSymptomatic peripheral arterial disease (PAD) results in significant gait impairment. In an attempt to fully delineate and quantify these gait alterations, we analyzed joint kinematics, torques (rotational forces), and powers (rotational forces times angular velocity) in patients with PAD with unilateral claudication for both the affected and nonaffected legs.MethodsTwelve patients with unilateral PAD (age, 61.69 ± 10.53 years, ankle-brachial index [ABI]: affected limb 0.59 ± 0.25; nonaffected limb 0.93 ± 0.12) and 10 healthy controls (age, 67.23 ± 12.67 years, ABI >1.0 all subjects) walked over a force platform to acquire gait kinetics, while joint kinematics were recorded simultaneously. Data were collected for the affected and nonaffected limbs during pain free (PAD-PF) and pain induced (PAD-P) trials. Kinetics and kinematics were combined to quantify torque and powers during the stance period from the hip, knee, and ankle joints.ResultsThe affected limb demonstrated significantly (P

Atherothrombosis, characterized by atherosclerotic plaque rupture and subsequent occlusive or subocclusive thrombus formation is the primary cause of acute ischemic syndromes involving all vascular beds and accounts for more than one-third of all deaths in the developed world. Platelet activation and aggregation constitute the most critical component in the pathophysiology of atherothrombotic disease. Aspirin is currently the most commonly used antiplatelet agent and one of the most frequently prescribed drugs, with as many as 30 million Americans on chronic aspirin regimens. Multiple well-designed prospective randomized clinical trials have demonstrated aspirin's efficacy in both primary and secondary prevention of a wide variety of entities that the atherothrombotic disease spectrum encompasses, such as cerebrovascular, coronary artery, and peripheral vascular disease. Despite its proven benefit, however, a growing body of evidence suggests that up to 70% of aspirin-takers may still be at risk for atherothrombotic complications due to resistance. Patients with laboratory-confirmed aspirin resistance seem to have an almost fourfold increase in their risk for acute thrombotic episodes, which underlines the magnitude of the problem for the vascular specialist. In this article, we review the physiology of platelet activation and the role of aspirin as an antiplatelet agent; the various laboratory assays used in assessing aspirin effectiveness; and current data on aspirin resistance and its clinical implications in patients with cardiovascular disease. We also review the studies that explore this phenomenon in patients with peripheral arterial disease and discuss the optimal management options in aspirin-resistant individuals. Suggestions are advanced for the direction of future trials evaluating aspirin resistance in patients with vascular disease.

To compare through a systematic review of published literature the stroke outcomes in protected and unprotected carotid artery stenting (CAS).PubMed and Cochrane electronic databases were queried to identify peer-reviewed publications from 1995 to 2007 meeting our pre-defined criteria for inclusion (English language, human only, at least 20 patients reported) and exclusion (procedures performed for the treatment of total occlusion, dissection, or aneurysmal disease; urgently performed procedures; use of covered stents; access other than transfemoral). Information was collected on a standardized data abstraction form for pooled analysis of total strokes within 30 days of procedure in all patients and in symptomatic and asymptomatic subgroups. A random effects meta-analysis of studies with concurrently reported data on protected and unprotected CAS was performed.Initial database query resulted in 2485 articles, of which 134 were included in the final analyses (12,263 protected CAS patients and 11,198 unprotected CAS patients). Twenty-four studies included data on both protected and unprotected CAS. Using pooled analysis of all 134 reports, the relative risk (RR) for stroke was 0.62 (95% CI 0.54 to 0.72) in favor of protected CAS. Subgroup analysis revealed a significant benefit for protected CAS in both symptomatic (RR 0.67; 95% CI 0.52 to 0.56) and asymptomatic (RR 0.61; 95% CI 0.41 to 0.90) patients (p0.05). Meta-analysis of the 24 studies reporting data on both protected and unprotected stenting demonstrated a relative risk of 0.59 (95% CI 0.47 to 0.73) for stroke, again favoring protected CAS (p0.001).Our systematic review indicated that the use of cerebral protection devices decreased the risk of perioperative stroke with CAS. A well designed randomized trial can further confirm our findings and possibly indicate the device with the best outcomes.

L'inversion du flux dans l'artere carotide interne (ACI) est une methode efficace de protection cerebrale au cours du stenting carotidien. Sa principale limite est qu'en l'absence de circulation collaterale adequate elle peut ne pas etre toleree par le malade. Le but de notre etude etait de determiner si l'identification pre-operatoire des collaterales intra-crâniennes par angioscanner ou arteriographie par resonance magnetique (ARM) permettait de predire un flux collateral suffisant et la tolerance neurologique de l'inversion du flux dans l'ACI destinee a la protection contre les embolies. Il s'agissait d'une etude de malades ayant une angioplastie et un stenting carotidien par voie cervicale. La neuroprotection a ete etablie par l'inversion du flux dans l'ACI. Tous les malades ont eu une angiographie non invasive cervicale et cerebrale pre-operatoire par angioscanner ou ARM et avaient au moins une artere collaterale intra-crânienne permeable. La pression residuelle moyenne dans l'artere carotide a ete mesuree. Les modifications neurologiques au cours du clampage carotidien et de l'inversion du flux ont ete surveillees de facon continue par electro-encephalographie (EEG). Trente-sept malades ayant au moins une artere collaterale intra-crânienne permeable a l'imagerie cerebrale par angioscanner ou ARM ont ete inclus. La pression residuelle moyenne dans l'artere carotide etait de 58 mmHg. Toutes les procedures ont ete des succes techniques. Aucune modification de l'EEG n'etait presente lors de l'occlusion de l'artere carotide primitive et de l'inversion du flux dans l'ACI. Une seule collaterale intra-crânienne permeable fournit une perfusion cerebrale suffisante pour realiser l'occlusion carotidienne et l'inversion du flux avec absence de modification de l'EEG. Les progres continus des modalites d'imagerie non invasive deviennent de plus en plus utiles pour notre comprehension de la physiologie cerebrale et la selection des malades pour les procedures carotidiennes invasives.

Internal carotid artery (ICA) flow reversal is an effective means of cerebral protection during carotid stenting. Its main limitation is that in the absence of adequate collateral flow it may not be tolerated by the patient. The purpose of this study was to determine if preoperative identification of intracranial collaterals with computerized tomographic (CTA) or magnetic resonance (MRA) angiography can predict adequate collateral flow and neurological tolerance of ICA flow reversal for embolic protection. This was a study of patients undergoing transcervical carotid angioplasty and stenting. Neuroprotection was established by ICA flow reversal. All patients underwent preoperative cervical and cerebral noninvasive angiography with CTA or MRA and had at least one patent intracranial collateral. Mean carotid artery back pressure was measured. Neurological changes during carotid clamping and flow reversal were continuously monitored with electroencephalography (EEG). Thirty-seven patients with at least one patent intracranial collateral on brain imaging with CTA or MRA were included. Mean carotid artery back pressure was 58 mm Hg. All procedures were technically successful. No EEG changes were present with common carotid artery occlusion and ICA flow reversal. One patent intracranial collateral provides sufficient cerebral perfusion to perform carotid occlusion and flow reversal with absence of EEG changes. Continued progress in noninvasive imaging modalities is becoming increasingly helpful in our understanding of cerebral physiology and selection of patients for invasive carotid procedures.

La inversion del flujo de la arteria carotida interna (ACI) es un medio eficaz de proteccion cerebral durante la implantacion de un stent carotideo. Su principal limitacion es que, en ausencia de flujo colateral adecuado, es posible que el paciente no lo tolere. El objetivo del presente estudio fue determinar si la identificacion preoperatoria de colaterales intracraneales con angiografia por tomografia computarizada (ATC) o por resonancia magnetica (ARM) puede predecir un flujo colateral adecuado y la tolerancia neurologica de la inversion del flujo de la ACI para la proteccion contra la embolizacion. La presente investigacion estudio a pacientes tratados mediante angioplastia e implantacion transcervical de un stent carotideo. La neuroproteccion se realizo mediante inversion del flujo de la ACI. Se realizo en todos los pacientes una angiografia cervical y cerebral no cruenta con ATC o ARM y se detecto, como minimo, una colateral intracraneal permeable. Se determino la presion retrograda media de la arteria carotida. Los cambios neurologicos durante el clampaje y la inversion del flujo de la carotida se monitorizaron de forma continua con electroencefalografia (EEG). Se incluyeron 37 pacientes con, al menos, una colateral intracraneal permeable observada en las imagenes cerebrales con ATC o ARM. La presion retrograda media en la arteria carotida fue de 58 mmHg. Todos los procedimientos se realizaron tecnicamente con exito. No se observaron cambios EEG con la oclusion de la arteria carotida comun y la inversion del flujo de la ACI. Una colateral intracraneal permeable proporciona la perfusion cerebral suficiente para realizar la oclusion e inversion del flujo de la carotida sin cambios en el EEG. El progreso continuado en las modalidades de diagnostico no invasivo por la imagen se esta haciendo de mayor utilidad en el conocimiento de la fisiologia cerebral y la seleccion de pacientes que van a ser tratados mediante procedimientos invasivos de la arteria carotida.

Con la complejidad cada vez mayor de los procedimientos endovasculares, ha aumentado la preocupacion relativa a la exposicion del paciente a la radiacion. La correccion de aneurisma aortico abdominal (AAA) representa el mas complejo de los procedimientos efectuados hoy dia por cirujanos vasculares. El presente estudio evalua la dosis de radiacion recibida por el paciente durante la reparacion endovascular de un AAA. Durante un periodo de 3 meses, monitorizamos prospectivamente la dosis de radiacion en una serie de pacientes sometidos a la reparacion endovascular de estas lesiones. Todos los pacientes se sometieron al procedimiento estandar con la implantacion de una de las endoprotesis disponibles comercialmente utilizando la unidad GE OEC 9800. Se registro la medicion directa de la dosis de maxima radiacion a nivel cutaneo (dosis cutanea pico, DCP) mediante una pelicula de dosimetria radiografica GAFCHROMIC. Con el dosimetro del brazo C se registraron mediciones indirectas de la dosis de radiacion (tiempo de fluoroscopia y producto dosis-area [PDA]). Se evaluo un total de 12 pacientes consecutivos, sometidos a la reparacion endovascular estandar de AAA. La DCP media fue de 0,75 Gy (limites 0,27-1,25). El tiempo medio de fluoroscopia total fue de 20,6 min (limites 12,6-34,2) con una media del 92% invertido en fluoroscopia estandar y un 8% invertido en cinefluoroscopia. Con respecto al tiempo de fluoroscopia total, el 49% se invirtio en un campo de vision normal y el 51%, en campo de vision aumentado. El PDA medio fue de 15.166 cGy/cm2 (limites 5.207-24.536). La DCP se correlaciono con el PDA (r = 0,9, p 0,05). La DCP tambien se correlaciono con el indice de masa corporal (IMC; r = 0,82, p

Avec la complexite croissante des procedures endovasculaires, l'interet s'est porte sur l'exposition des patients aux radiations. Le traitement des anevrismes de l'aorte abdominale (AAA) est la procedure endovasculaire la plus complexe realisee par les specialistes vasculaires. Notre etude evalue la dose de radiations recue par les patients au cours du traitement endovasculaire des AAA. Sur une periode de trois mois nous avons surveille de maniere prospective la dose de radiations chez des patients consecutifs ayant le traitement endovasculaire d'un AAA. Tous les patients ont eu le traitement endovasculaire standard d'un AAA avec une des deux protheses disponibles dans le commerce en employant l'unite GE OEC 9800. La mesure directe de la dose de rayonnement maximum au niveau de peau (pic de dose cutanee, PDC) a ete enregistree en employant le film radiographique de dosimetrie GAFCHROMIC. Des mesures indirectes de la dose de radiation (temps de fluoroscopie et produit dose-surface [PDS]) ont ete enregistrees avec le dosimetre de l'arceau. Douze patients consecutifs ayant le traitement endovasculaire standard d'un AAA ont ete evalues. Le PDC moyen etait de 0,75 Gy (extremes 0,27-1,25). Le temps total moyen de fluoroscopie etait de 20,6 min (extremes 12,6-34,2) avec une moyenne de 92% du temps passes en fluoroscopie standard et de 8% passes en cinefluoroscopie. Concernant le temps total de fluoroscopie, 49% etaient passes en champ normal et 51% en vue agrandie. Le PDS moyen etait de 15 166 cGy · cm2 (extremes 5 207-24 536). Le PDC etait correle avec le PDS (r = 0,9, p 0,05). Le PDS etait egalement correle avec l'index de masse corporelle (IMC; r = 0,82, p

Objective Claudication is the most common manifestation of peripheral arterial disease (PAD), producing significant ambulatory compromise. The gait of claudicating patients has been evaluated using primarily temporal and spatial parameters. With the present study, we used advanced biomechanical measures to further delineate the ambulatory impairment of claudicating patients. We hypothesized that the claudicating legs of PAD patients have an altered kinetic gait pattern compared with normal legs from control subjects. Methods Ambulation kinetics (ground reaction forces) were evaluated in claudicating patients and compared with age-matched healthy controls. Forces were analyzed in the vertical, anterior–posterior, and medial–lateral directions. Time from heel touch-down to toe-off (stance time) and time spent in double-limb support were also evaluated. Results The study recruited 14 PAD patients (age, 58 ± 3.4 years; weight, 80.99 ± 15.64 kg) with femoropopliteal occlusive disease (ankle-brachial index [ABI], 0.56 ± 0.03) and five controls (age, 53 ± 3.4 years; weight, 87.38 ± 12.75 kg; ABI, ≥1.00). Vertical force curve evaluation demonstrated significant flattening in claudicating patients resulting in a lower and less fluctuant center of mass when ambulating. In the anterior–posterior direction, claudicating patients demonstrated significantly decreased propulsion forces. In the medial–lateral direction, they had significantly increased forces consistent with wider steps and an inability to swing their legs straight through. Claudicating patients demonstrated a greater stance time and time in double limb support compared with healthy controls. Most importantly, gait abnormalities were present before the onset of claudication, with gait worsening after the onset of claudication. Conclusion Claudicating patients demonstrate significant gait impairments that are present even before they experience any limb discomfort. These alterations may make them feel more stable and secure while attempting to minimize use of the affected limb. Advanced biomechanical analysis, using ambulation kinetics, permits objective and quantitative evaluation of the gaits of claudicating patients. Such evaluation may point to new rehabilitation strategies and provide objective measurement of functional outcomes after medical and surgical therapy.

Thirty-eight abstracts were accepted for presentation at the 26th Annual Meeting of the Association for Surgical Education, held in Tucson, Arizona. Based on common themes, 10 abstracts were chosen for publication under the auspices of the Alliance for Clinical Education. Two abstracts involved operating room simulations. Authors of the 1st abstract used the simulated environment to evaluate team training, whereas the 2nd abstract assessed intraoperative stress and coping strategies during a carotid endarterectomy. Six abstracts explored aspects of newer teaching models used for instructing medical students and residents. Cognitive task analysis and computer-based video training were used to teach and assess procedural skills. Preliminary results were reported, assessing the impact of Web-based, multimedia problem-based teaching modules on clinical reasoning skills. A preclinical skills course improved students' assessment of their proficiency, confidence, and anxiety levels. A student-s ability ...

Carotid angioplasty and stenting are progressively earning a role as a less invasive alternative in the treatment of carotid occlusive disease. The most common approach for carotid artery stenting involves transfemoral access and use of a filter or balloon device for neuroprotection. This approach has limitations related to both the site of access and the method of neuroprotection. Specifically, an aortoiliac segment with advanced occlusive or aneurysmal disease or an anatomically unfavorable or atheromatous arch and arch branches can significantly limit the safety of the retrograde transfemoral pathway to the carotid bifurcation. Additionally, data provided by the use of transcranial Doppler monitoring and diffusion-weighted magnetic resonance imaging in patients undergoing filter- or balloon-protected carotid artery stenting demonstrate that currently available devices are associated with a considerable incidence of cerebral embolization. To address these limitations, we, along with others, have employed a direct transcervical approach for carotid artery stenting that incorporates the principle of flow reversal for neuroprotection. The technique bypasses all of the anatomic limitations of transfemoral access and simplifies the application of flow reversal, which is one of the safest neuroprotection techniques. The purpose of this review is to describe our method of transcervical carotid artery stenting, review the accumulating outcomes data, and discuss the clinical advantages of and indications for this increasingly popular technique.

A total of 37 abstracts were accepted for presentation at the 25th Annual Meeting of the Association for Surgical Education, held in New York City, NY. Of those, 11 were chosen for publication in these proceedings based on common themes; work hours and the Accreditation Council for Graduate Medical Education competencies impacted heavily on the themes pursued this year. Abstracts explored how faculty and residents view the duty hour restrictions, whether the restrictions have created an ethical dilemma for residents, the communication factors that affect shared understanding of the hospitalized patients, and the identification of key surgical stressors and their impact on practice and coping strategies. Abstracts also assessed the impact of the 80-hr work week on education. Two abstracts focused on medical students. One correlated work hours with sleep and objective measures of performance, whereas a second proposed to determine the proportion of night and weekend call spent in educational pursuits. Both ...

PURPOSE To report our initial experience using a transcervical approach for carotid angioplasty/stenting (CAS) that employs internal carotid artery (ICA) flow reversal for neuroprotection. METHODS Seventeen patients (15 men; mean age 65 years, range 49-77) with significant carotid stenosis (mean 88%, 8 symptomatic) were treated with protected transcervical CAS. Eleven patients were considered at high risk for carotid endarterectomy; 8 were also considered high risk for transfemoral access (unfavorable aortic arch anatomy or advanced aortoiliac occlusive disease). Anesthesia was based on patient and anesthesiologist preferences. The approach consisted of a 2-cm cutdown over the common carotid artery and placement of a 9-F sheath. ICA flow was reversed and shunted into the jugular vein during the carotid intervention. RESULTS Access and carotid stenting were successful in all cases. Thirteen procedures were performed under general and 4 under local anesthesia. Mean flow reversal time was 34+/-4 minutes (25 minutes in the last 7 cases). The patients tolerated the procedure well and had no neurological events. Four (23%) patients had significant oozing from the operative site; 2 developed small neck hematomas that were treated conservatively. All patients were discharged on the first postoperative day. There were no deaths, changes in neurological status, or restenosis over a mean follow-up of 12 months (range 1-24). CONCLUSIONS Our initial experience demonstrates that a transcervical approach is a viable alternative for CAS. The procedure can be performed safely, with good initial clinical outcomes. The approach allows carotid flow reversal and emboli protection without introducing neuroprotection devices. The method appears best suited for patients at high risk for endarterectomy and transfemoral access.

Defining the region known as the Southwest is a project that keeps many geographers pleasantly and securely employed. As D. W. Meinig famously quipped, "The Southwest is a distinctive place to the American mind but a somewhat blurred place on American maps, which is to say that everyone knows that there is a Southwest but there is little agreement as to just where it is" (3). In spite of the great variability, complexity, and subjectivity of definitions geographers promulgate, however, when one distills the matter the region is nearly always defined along the intersection of two axes, one cultural and the other natural. Certain characteristics of these two axes are obvious in the six

OBJECTIVE—Pancreas transplantation (PTX) normalizes glucose and improves microvascular complications, but its impact on macrovascular disease is still debated. RESEARCH DESIGN AND METHODS—Carotid intima-media thickness (IMT), shown to correlate with cardiovascular disease (CVD) risk and events, was determined prospectively by ultrasonography in successful pancreas transplant recipients to evaluate the effect of PTX on CVD risk. Carotid IMT and CVD risk factors of pancreas transplant recipients (n = 25) were compared with three groups: individuals with type 1 diabetes without significant nephropathy (n = 20), nondiabetic kidney transplant recipients (n = 16), and normal control subjects (n = 32). Mean age of pancreas transplant recipients at the time of transplantation was 42.4 ± 1.2 years (mean ± SE) and duration of diabetes was 25.9 ± 1.4 years. RESULTS—After PTX, HbA1c level (P < 0.0001) decreased to normal and, whereas creatinine level (P = 0.0002) decreased, it remained elevated compared with normal control subjects (P < 0.05). Blood pressure, BMI, fasting lipid levels, smoking frequency, and use of hypolipidemic agents were unchanged. Mean carotid IMT was increased in pancreas transplant candidates but decreased by 1.8 ± 0.1 year after PTX (P = 0.0068), no longer different from that in normal control subjects or patients with type 1 diabetes. CONCLUSIONS—Carotid IMT improves after successful PTX within 2 years of the procedure, with normalization of HbA1c and improved renal function, independent of changes in lipid levels, BMI, blood pressure, smoking, or use of hypolipidemic agents. This study suggests that CVD risk, future events, and mortality should improve after PTX in the absence of other significant, untreated CVD risk factors.

Objective To explore the relationship between learning preferences, attitudes towards computers, and student evaluation of a computer-assisted instructional (CAI) program. Context A third year required clerkship in surgery at the University of Nebraska Medical Center. Methods A mixed-methods design combining attitudinal measures and qualitative interviews was employed to assess student reactions to a CAI program on angiography completed during a required surgical clerkship. Between January 1998 and July 1999, 151 students completed the program. Prior to participating, students completed the Rezler Learning Preference Inventory (LPI) and a computer attitudes survey (CAS). The LPI characterizes learning preferences as being abstract or concrete, individual or interpersonal, and student-structured or teacher-structured. The CAS measures attitudes towards computers and their role in education. After using the CAI program, students evaluated the module by completing an 18 item questionnaire. Based on LPI and CAS scores, 31 students were invited to participate in an in-depth qualitative interview on their experiences and perceptions of the program. Results There was no relationship between learning preferences, computer attitudes, and evaluation of the CAI program. Students were very positive about the program's content, clarity, organization, and ease of use. They also rated it as efficient and effective. However, many still indicated a preference for lecture and text-based learning. Qualitative interviews suggest students worry computers will supplant student–teacher contact. Conclusions Learning preferences and prior attitudes toward computers did not bias student reactions to the CAI program assessed in this study. However, students expressed concerns that CAI would interfere with the traditional student–teacher encounter and relationship.

Background. Pancreas transplantation (PTX) improves diabetic microvascular complications, but it is unknown whether PTX alters macrovascular disease. Carotid intima media thickness (IMT) has been shown to correlate with cardiovascular events, so this study was designed to evaluate changes in carotid IMT after PTX. Methods. Four groups were studied: PTX candidates (n=60); successful PTX recipients (n=89; mean time since PTX=4.0±0.3 years); patients with type 1 diabetes but without nephropathy (n=20); and normal controls (n=32). Mean IMT and mean of maximum carotid IMT measurements (mean-max IMT), hemoglobin A1C, serum creatinine, body mass index (BMI), blood pressure, smoking status, use of hypolipidemic medications, and fasting lipids were determined in all groups. Results. Age, gender distribution, and BMI were not different among the groups. Duration of diabetes was also equal between pre- and post-PTX groups. Mean and mean-max IMT were greatest pre-PTX and decreased after PTX (P

IMPORTANCE: Growing consensus suggests that frailty-associated risks should inform shared surgical decision making. However, it is not clear how best to screen for frailty in preoperative surgical populations. OBJECTIVE: To develop and validate the Risk Analysis Index (RAI), a 14-item instrument used to measure surgical frailty. It can be calculated prospectively (RAI-C), using a clinical questionnaire, or retrospectively (RAI-A), using variables from the surgical quality improvement databases (Veterans Affairs or American College of Surgeons National Surgical Quality Improvement Projects). DESIGN, SETTING, AND PARTICIPANTS: Single-site, prospective cohort from July 2011 to September 2015 at the Veterans Affairs Nebraska–Western Iowa Heath Care System, a Level 1b Veterans Affairs Medical Center. The study included all patients presenting to the medical center for elective surgery. EXPOSURES: We assessed the RAI-C for all patients scheduled for surgery, linking these scores to administrative and quality improvement data to calculate the RAI-A and the modified Frailty Index. MAIN OUTCOMES AND MEASURES: Receiver operator characteristics and C statistics for each measure predicting postoperative mortality and morbidity. RESULTS: Of the participants, the mean (SD) age was 60.7 (13.9) years and 249 participants (3.6%) were women. We assessed the RAI-C 10 698 times, from which we linked 6856 unique patients to mortality data. The C statistic predicting 180-day mortality for the RAI-C was 0.772. Of these 6856 unique patients, we linked 2785 to local Veterans Affairs Surgeons National Surgical Quality Improvement Projects data and calculated the C statistic for both the RAI-A (0.823) and RAI-C (0.824), along with the correlation between the 2 scores (r = 0.478; P < .001). Of these 2785 patients, there were sufficient data to calculate the modified Frailty Index for 1021, in which the C statistics were 0.865 (RAI-A), 0.797 (RAI-C), and 0.811 (modified Frailty Index). The correlation between the RAI-A and RAI-C was 0.547, and the correlations of the modified Frailty Index to the RAI-A and RAI-C were 0.301 and 0.269, respectively (all P < .001). A cutoff of RAI-C of at least 21 classified 18.3% patients as “frail” with a sensitivity of 0.50 and specificity of 0.82, whereas the RAI-A was less sensitive (0.25) and more specific (0.97), classifying only 3.7% as “frail.” CONCLUSIONS AND RELEVANCE: The RAI-C and RAI-A represent effective tools for measuring frailty in surgical populations with predictive ability on par with other frailty tools. Moderate correlation between the measures suggests convergent validity. The RAI-C offers the advantage of prospective, preoperative assessment that is proved feasible for large-scale screening in clinical practice. However, further efforts should be directed at determining the optimal components of preoperative frailty assessment.

Introduction: End-of-life surgical care is a major concern with a significant number of operations performed within the last year of life; surgery for hip fractures is a prime example. Unfortunately, no simple objective tool exists to assess life expectancy in the postoperative period. The goal of our study was to analyze 2 simple geriatric life expectancy calculators to compare with the current Veterans Affairs Surgical Quality Improvement Program (VASQIP) postoperative 30-day mortality calculator. Methods: This retrospective study assessed the utility of 3 validated calculators in 47 hip fracture repairs from July 2009 to May 2011. The tools included: 30-day VASQIP mortality calculator, 6-month Minimum Data Set Mortality Risk Index-Revised (MMRI-R), and Four-Year Mortality Index. The VASQIP calculator requires chart review, Current Procedural Terminology (CPT) codes, and laboratory analysis, whereas the mortality risk indices require simple patient questioning if prospective or simple chart review if retrospective. Scoring was performed and mortality risk was compared between survivors and nonsurvivors. Results: A total of 47 hip fractures were repaired during the study period with 37 survivors and 10 nonsurvivors. In all, 7 died within 30 days, 2 died within 6 months, and 1 died greater than 6 months after surgery. The mean age (standard deviation [SD]) of all patients undergoing hip fracture repair was 73.6 (13.3) years. The VASQIP calculator mean (SD) 30-day mortality risk was 10.4% (5.4) for nonsurvivors compared to survivors 4.3% (5.5), P < .003; the MMRI-R mean (SD) mortality risk was 35.8% (15.4) for nonsurvivors compared to survivors 14.7% (9.5), P < .001; the Four-Year Mortality Index mean (SD) mortality risk was 60.9% (16.9) for nonsurvivors compared to survivors 48.9% (24.4), P < .09. Conclusion: Overall, the VASQIP 30-day and MMRI-R 6-month mortality calculators showed significant differences in mortality risk between survivors versus nonsurvivors in a population with hip fracture. In contrast, the Four-Year Mortality calculator may not sufficiently discriminate operative risk. The easily obtained MMRI-R has the potential to provide information on short-term postoperative mortality risk.

Importance Because of the similarity in clinical outcomes after elective open and endovascular repair of abdominal aortic aneurysm (AAA), cost may be an important factor in choosing a procedure. Objective To compare total and AAA-related use of health care services, costs, and cost-effectiveness between groups randomized to open or endovascular repair. Design, Setting, and Participants This unblinded randomized clinical trial enrolled 881 patients undergoing planned elective repair of AAA who were candidates for open and endovascular repair procedures. Patients were randomized from October 15, 2002, to April 15, 2008, at 42 Veterans Affairs medical centers. Follow-up was completed on October 15, 2011, and data were analyzed from April 15, 2013, to April 15, 2016, based on intention to treat. Main Outcomes and Measures Mean total and AAA-related health care cost per life-year and per quality-adjusted life-year (QALY). Results A total of 881 patients (876 men [99.4%]; 5 women [0.6%]; mean [SD] age, 70 [7.8] years) were included in the analysis. After a mean of 5.2 years of follow-up, mean life-years were 4.89 in the endovascular group and 4.84 in the open repair group ( P = .68), and mean QALYs were 3.72 in the endovascular group and 3.70 in the open repair group ( P = .82). Total mean health care costs did not differ significantly between the 2 groups (endovascular group, $142 745; open repair group, $153 533; difference, −$10 788; 95% CI, −$29 796 to $5825; P = .25). Costs related to AAA, including the initial repair, constituted nearly 40% of total costs and did not differ significantly between the 2 groups (endovascular group, $57 501; open repair group, $57 893; difference, −$393; 95% CI, −$12 071 to $7928; P = .94). Lower costs due to shorter hospitalization for initial endovascular repair were offset by increased costs from AAA-related secondary procedures and imaging studies. The probability of endovascular repair being less costly and more effective was 56.8% when effectiveness was measured in life-years and 55.4% when effectiveness was measured in QALYs for total costs and 31.3% and 34.3%, respectively, for AAA-related costs. Conclusions and Relevance In this multicenter randomized clinical trial with follow-up to 9 years, survival, quality of life, costs, and cost-effectiveness did not differ between elective open and endovascular repair of AAA. Trial Registration clinicaltrials.gov Identifier:NCT00094575

Background: A previous study evaluated repeated, serial administrations of computer-based simulations. The data demonstrated an increase in scores across rotations during the academic year, but no difference between scores in successive years. Methods: The initial study only indirectly assessed the effect of information sharing on measured performance. To directly assess the effect of information transfer, 8 computer-based case simulations were administered over 2 consecutive years to 220 third-year students at the conclusion of 12 surgical clerkship rotations (6 per year). During the second year of administration information regarding content area, in the form of the case stem or introductory lead-in material, was provided to each rotation of students prior to the examination based on a sequential algorithm. Results: The data demonstrate no increase in overall mean score for the examination over the 2 years. Scores were significantly different for 2 of the 8 cases, increasing in the one and decreasing in the other. Conclusions: The data demonstrate no evidence that prior knowledge of content area influences the scores of successive classes on computerized models of performance assessment.

Purpose: This review examines the many techniques that have been used for the non-invasive diagnosis of acute and chronic venous disease and was conducted by members of the Committee on Research of the American Venous Forum. It proposes to identify those techniques with the greatest clinical potential, to suggest algorithms for the clinical application of non-invasive techniques in the identification of acute deep venous thrombosis and chronic venous insufficiency, and to identify areas of deficient knowledge and potential areas for future research initiatives. Methods: Review of pertinent clinical and research material. Results: Impedance plethysmography and ultrasonic imaging are the primary non-invasive tools used in the diagnosis of acute deep venous thrombosis. At present, ultrasonic imaging techniques are recommended on the basis of greater diagnostic accuracy in recent comparative clinical trials. Data would suggest that serial evaluation should probably be viewed as the preferred option for symptomatic patients with a negative initial examination and the presence of risk factors or physical findings suggesting a proximal deep venous obstruction/thrombosis. Chronic venous disease is the result of valvular incompetence, with or without associated venous obstruction. Duplex imaging can be used to determine the location and extent of reflux; however, there are reported procedural variations in the performance and interpretation of such studies. Recent innovations in air plethysmography may provide a means of quantifying volume changes, and permit an objective characterization of venous reflux and calf pump efficiency. Conclusions: There are still significant questions that need to be answered by well-designed research initiatives. Research applications that incorporate non-invasive diagnostic techniques may involve the diagnosis, treatment and natural history of acute deep venous obstruction/thrombosis and chronic venous insufficiency, assessment prior to and following venous reconstruction, and the basic science aspects of acute and chronic venous disease. At present, a lack of common standards is, by far, the greatest impediment to an organized research approach to venous disease.

Background: Computer-based examination formats permit evaluation of patient care strategies in a realistic context. Because such examinations are complex and difficult to develop, the same case simulations must often be used on multiple occasions. Methods: To determine if repeated, serial administration of computerized case simulations influences performance, 8 simulations were administered over 2 consecutive years to 252 third-year medical students at the conclusion of 16 surgical clerkship rotations (8 per year). One-way analyses of variance were used to compare scores across rotations during the year and to compare scores between 2 consecutive academic years. Scheffe pairwise comparisons were used to identify trends within each academic year. Results: The data demonstrate an increase in scores across rotations during the year. There is, however, no difference between scores in successive years. Conclusions: The data are consistent with an increase in knowledge during the course of the year, without evidence that test information transfer influences the performance of successive classes.

Steal syndrome is a well-described complication of arteriovenous fistulas used for hemodialysis access. Although distal revascularization with interval ligation appears to offer the greatest likelihood of symptom relief and vascular access salvage, not all fistulas are amenable to this procedure, particularly distal radiocephalic arteriovenous fistulas. In this report, we describe the treatment of steal syndrome in a patient with a distal radiocephalic arteriovenous fistula using a percutaneous approach and endovascular coils. After coil embolization of the distal radial artery and multiple collateral vessels, steal was no longer visualized using angiography, and the patient’s symptoms resolved.

The purpose of this review is to define animal models of chronic venous disease and to demonstrate how animal studies can impact our understanding and treatment of this disorder. To this end an extensive literature search was conducted highlighting potential animal models of chronic lower extremity venous disease. Scientific investigations using animals to study particular aspects of this disease are also reviewed. This review was conducted by members of the Committee on Research of the American Venous Forum to help provide direction for future venous research endeavors. Useful models of chronic venous occlusive disease involve controlled ligation of a major lower limb vein and multiple tributaries. Such a model can provide sustained venous hypertension and studies using this model have confirmed that an isodiametric graft can provide early hemodynamic relief. Models of primary, postphlebitic, and isolated chronic deep venous insufficiency are available for study. Valve repair or transplantation can positively impact the insufficiency observed in these models. Investigations into valve substitutes have generally been disappointing or are undergoing early evaluation. In conclusion, animal models for the study of some aspects of chronic venous disease do exist and have already affected our clinical approach to patients. The scientific study of basic pathophysiology, diagnostics, end-organ response, and long-term surgical treatments of this disorder in well-controlled animal experiments have not been conducted. (Ann Vasc Surg 1998;12:487–494.)

Background: The Kolb Learning Style Inventory (LSI) measures preference for each of four learning orientations: abstract conceptualization, concrete experience, active experimentation, and reflective observation. These orientations define four learning styles: convergence, divergence, assimilation, and accommodation. Methods: To determine if learning style correlates with objective multiple-choice and clinical measures of performance, the learning styles of third-year medical students (n = 227) were evaluated using the LSI. Performance was assessed using the United States Medical Licensing Examination step 1 (USMLE 1), the National Board of Medical Examiners (NBME) multiple-choice surgical subject examination (MCQ), and NBME computer-based case simulations (CBX). Results: The data showed a significant ( P ≤0.05) relationship between learning style and performance on the USMLE 1. There was a significant ( P ≤0.05) and direct correlation between an abstract orientation and performance on the USMLE 1 ( r = 0.33) and MCQ ( r = 0.20). There was no relationship between learning style and clinical performance measured using the CBX. Conclusions: These data demonstrate that performance on objective measures of academic achievement is influenced by learning style, while application of that knowledge in the management of clinical situations may require additional skills beyond those measured.