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James C Stanley

Publications and source records attributed to James C Stanley.

At least 37 records · Page 2Linked to original sources

Tamoxifen up-regulates catalase production, inhibits vessel wall neutrophil infiltration, and attenuates development of experimental abdominal aortic aneurysms.

BACKGROUND: Selective estrogen receptor modulators (SERMs), similar to estrogens, possess vasoprotective effects by reducing release of reactive oxygen species. Little is known about the potential effects of SERMs on the pathogenesis of abdominal aortic aneurysms (AAAs). This study's objective was to investigate the growth of experimental AAAs in the setting of the SERM tamoxifen. METHODS: In the first set of experiments, adult male rats underwent subcutaneous tamoxifen pellet (delivering 10 mg/kg/day) implantation (n = 14) or sham operation (n = 16). Seven days later, all animals underwent pancreatic elastase perfusion of the abdominal aorta. Aortic diameters were determined at that time, and aortas were harvested 7 and 14 days after elastase perfusion for immunohistochemistry, real-time polymerase chain reaction, Western blot analysis, and zymography. In the second set of experiments, a direct irreversible catalase inhibitor, 3-amino-1,2,4-triazole (AT), was administered intraperitoneally (1 mg/kg) daily to tamoxifen-treated (n = 6) and control rats (n = 6), starting on day 7 after elastase perfusion. Aortic diameters were measured on day 14. In a third set of experiments, rats were perfused with catalase (150 mg/kg) after the elastase (n = 5), followed by daily intravenous injections of catalase (150 mg/kg/day) administered for 10 days. A control group of rats (n = 7) received 0.9% NaCl instead of catalase. RESULTS: Mean AAA diameters were approximately 50% smaller in tamoxifen-treated rats compared with sham rats 14 days after elastase perfusion (P = .002). The tamoxifen-treated group's aortas had a five-fold increase in catalase mRNA expression (P = .02) on day 7 and an eight-fold increase in catalase protein on day 14 (P = .04). Matrix metalloprotroteinase-9 activity was 2.4-fold higher (P = .01) on day 7 in the aortas of the controls compared to the tamoxifen-treated group's aortas. Tamoxifen-treated rats had approximately 40% fewer aortic polymorphonuclear neutrophils compared to controls on day 7 (P = .05). Administration of the direct catalase inhibitor AT to tamoxifen-treated rats partially reversed the aneurysm inhibitory effect of tamoxifen by nearly 30% (P = .02). In contrast, catalase administration inhibited AAA formation by 44% (P = .002). CONCLUSIONS: The selective estrogen receptor modulator tamoxifen inhibits the development of AAAs in male rats in association with an up-regulation of catalase and inhibition of aortic wall neutrophil infiltration.

Amitrole↗

Mitochondrial-dependent apoptosis in experimental rodent abdominal aortic aneurysms.

OBJECTIVES: While extrinsic mechanisms of apoptosis in abdominal aortic aneurysms (AAAs) are recognized, this project hypothesizes that an intrinsic, mitochondrial-dependent, mechanism of apoptosis also contributes to experimental AAA formation. METHODS: Rat aortas were perfused with either saline or elastase (N = 5 per group) and harvested 7 days postperfusion. The aortas were placed in gluteraldehyde for subsequent transmission electron microscopy, Bouin's solution for TUNEL, or paraformaldehyde for immunohistochemical staining for caspase-9, caspase-3, and Bid. RESULTS: Abdominal aortic diameters increased 168 +/- 25% (mean +/- SEM) after elastase perfusion. compared with 30 +/- 5% after saline perfusion (P < .001). Apoptosis of aortic smooth muscle cells, macrophages, and neutrophils was evidenced by transmission electron microscopy and TUNEL in the elastase-perfused aneurysmal aortas. Quantitative analysis of the apoptotic cells revealed a significant (P < .01) increase in the number of total apoptotic cells in the elastase-perfused aortas (12 +/- 3 cells per high-power field), compared with that of saline-infused controls (1.3 +/- 0.2). Caspase-9, the key initiator in the mitochondrial-dependent apoptotic pathway, stained positively in only elastase-perfused aortas. Bid staining was not detected in either the elastase-perfused aortas or the saline controls. CONCLUSIONS: Apoptosis is evident in multiple cell lines in elastase-perfused aneurysmal aortas, but rarely observed in control aortas. Caspase-9, the key initiator of intrinsic apoptosis, was documented only in elastase-perfused aortas. These results suggest that mitochondrial-dependent apoptosis is associated with abdominal aortic aneurysm formation.

Animals↗

Carotid endarterectomy remains the standard of care, even in high-risk surgical patients.

OBJECTIVE: This study tested the hypothesis that high-risk patients can undergo carotid endarterectomy without associated increased risk of stroke, transient ischemic attack (TIA), or death. SUMMARY BACKGROUND DATA: Carotid endarterectomy (CEA) has clearly been shown to be effective in reducing the risk of stroke in selected symptomatic and asymptomatic patients with extracranial carotid stenosis. However, recently, carotid angioplasty with stenting (CAS) has been suggested as an alternative treatment in high-risk surgical patients. METHODS: Medical records for consecutive patients who underwent CEA from 1996 to 2001 were reviewed for demographics, medical history, and hospital course. High-risk patients were defined as those experiencing a myocardial infarction (MI) or an exacerbation of congestive heart failure (CHF) within 4 weeks before CEA; unstable angina; steroid-dependent chronic obstructive pulmonary disease (COPD); prior ipsilateral CEA, neck dissection or irradiation; high carotid bifurcation; and those with combined cardiac-carotid procedures. Poor postoperative outcome was defined as stroke, TIA, or death within 30 days. Univariate, multivariate, and Kaplan-Meier analysis were used as appropriate. RESULTS: Four hundred twenty-nine patients underwent 499 CEAs, of which 84 (17%) were considered high risk. The overall stroke-death rate among all patients was 2.8%. A total of 11 postoperative strokes (2.2%), 7 TIAs (1.4%), and 3 deaths (0.6%) occurred within 30 days after surgery. There was no difference in 30-day poor outcome between high- and low-risk patients (4.8% vs. 4.1%, P = 0.77). When these risk factors were assessed independently, those with recent MI were at higher risk for poor outcome (odds ratio [OR], 13.3; 95% confidence interval [CI], 2.2-82.0; P = 0.03). Multivariate analysis also revealed that a history of contralateral stroke or TIA conferred an increased risk of poor outcome (OR, 3.0; 95% CI, 1.1-8.4; P = 0.02), whereas use of preoperative angiotensin-converting enzyme inhibitors was associated with reduced risk (OR, 0.36; 95% CI, 0.11-1.0; P = 0.05), as was a history of hyperlipidemia (OR, 0.33; 95% CI, 0.13-0.87; P = 0.03). By log-rank analysis, 12-month survival was significantly worse in the high-risk group as compared with the low-risk (96% vs. 91%, P = 0.03). CONCLUSIONS: Patients considered a surgical high risk can undergo CEA without any worse outcome compared with those patients deemed low risk. The benefit of CAS will likely be marginal, and only controlled clinical trials will be able to determine if certain subgroups demonstrate improved outcome with CAS. Carotid endarterectomy remains the standard of care, even in high-risk surgical patients.

Aged↗

Osteomyelitis of the foot and toe in adults is a surgical disease: conservative management worsens lower extremity salvage.

OBJECTIVE: To characterize the national epidemiology of adult osteomyelitis (OM) and, using a single institutions' experience, test the hypothesis that early surgical therapy as compared with antibiotics alone results in an improved chance of wound healing and limb salvage. BACKGROUND: Foot and digit OM is a very common problem for which management is variable and for which few guidelines exist. METHODS: The Nationwide Inpatient Sample (NIS) and a single institution review from 1993 to 2000 form the basis of this study, using ICD-9CM codes for lower extremity foot and digit OM. Demographics, risk factors, and treatments were analyzed against the outcomes of a healed wound, limb salvage, and death. RESULTS: The NIS included 51,875 patients (incidence = 9/10,000 patients per year) with a mean age of 60 years, and 59% were men. The median length of stay decreased from 9 to 6 days (P < 0.001), but the average admission charge of 19,000 dollars did not significantly decrease over 7 years. Of these patients, 23% underwent a digit amputation and 8.5% suffered proximal limb loss. Single-institution analysis of 237 consecutive patients with OM confirmed a similar mean age (58 years), gender (67% men), and most presented with a foot or digit ulcer (56%). Wound healing was achieved in 56% and overall limb salvage was 80%. Decreased wound healing was associated with peripheral vascular occlusive disease (odds ratio, 0.4; 95% confidence interval, 0.2-0.8, P = 0.006) and preadmission antibiotic use (odds ratio, 0.2; 95% confidence interval, 0.05-1.1, P=0.07), while surgical debridement (odds ratio, 2.2; 95% confidence interval, 1.2-4.2, P = 0.02) was associated with increased healing. Limb salvage was improved with an arterial bypass (odds ratio, 3.9; 95% confidence interval, 1.1-14, P = 0.04), while preadmission solid organ transplant (odds ratio, 0.37; 95% confidence interval, 0.14-0.96, P = 0.04), peripheral vascular occlusive disease (odds ratio, 0.25; 95% confidence interval, 0.12-0.5, P = 0.001), and preadmission antibiotic use (odds ratio, 0.34; 95% confidence interval, 0.15-0.77, P = 0.009) were associated with greater limb loss. CONCLUSION: Digit OM is an expensive and morbid disease. Aggressive surgical debridement/digit amputation and selected use of arterial bypass should improve wound healing and limb salvage, respectively. In contrast, antibiotic therapy alone is associated with decreased wound healing and limb salvage.

Aged↗

Gender differences in experimental aortic aneurysm formation.

OBJECTIVE: It is hypothesized that a male predominance, similar to that in humans, persists in a rodent model of experimental abdominal aortic aneurysm (AAA) via alterations in matrix metalloproteinases (MMPs). METHODS AND RESULTS: Group I experiments were as follows: elastase perfusion of the infrarenal aorta was performed in male (M) and female (F) rats. At 14 days, aortas were harvested for immunohistochemistry, real-time polymerase chain reaction (PCR), and zymography. Group II experiments were the following: abdominal aorta was transplanted from F or M donors into F or M recipients. At 14 days, rodents that had undergone transplantation underwent elastase perfusion. In group III, male rats were given estradiol or sham 5 days before elastase perfusion. In group I, M rats had larger AAAs with higher frequency than did F rats. M rat aortas had more significant macrophage infiltrates and increased matrix metalloproteinase (MMP)-9 production and activity. In group II, M-to-M aortic transplants uniformly developed aneurysms after elastase perfusion, whereas F-to-F aortic transplants remained resistant to aneurysm formation. F aortas transplanted into M recipients, however, lost aneurysm resistance. In group III, estradiol-treated rats demonstrated smaller aneurysms and less macrophage infiltrate and MMP-9 compared with M controls after elastase. CONCLUSIONS: These data provide evidence of gender-related differences in AAA development, which may reflect an estrogen-mediated reduction in macrophage MMP-9 production.

Animals↗

Effect of increasing patient age on complication rates following intact abdominal aortic aneurysm repair in the United States.

INTRODUCTION: Advanced age is generally acknowledged as a risk factor for adverse surgical outcomes, but little information exists to define the magnitude of this association from a population-based perspective. This study was undertaken to determine the relation of patient age to complications following abdominal aortic aneurysm (AAA) repair in a population-based experience. METHODS: This study was based upon data from 6397 patients with a primary diagnosis of intact AAA and a procedure code for repair of AAA from the Nationwide Inpatient Sample (NIS) in 2000. The NIS is a 20% stratified random sample representative of all United States hospitals. Primary outcome variables were postoperative complications determined from secondary diagnostic codes. Adjustment for confounding variables was performed using multiple logistic regression. RESULTS: At least one complication affected 29% of patients. Increasing age correlated with a higher risk of having one or more complications (51-60 years, 18.8%; 61-70 years, 27.3%; 71-80 years, 31.2%; >80 years, 34.3%; P < 0.01). Comparison of the oldest to the youngest age group revealed an increased incidence of pulmonary insufficiency (13.9% versus 6.4%), pneumonia (7.7% versus 3.0%), reintubation (9.5% versus 3.9%), acute renal failure (8.8% versus 2.5%), myocardial infarction (4.3% versus 1.6%), and mortality (7.9% versus 1.1%). The association of increasing age to complications and mortality persisted after adjusting for patient case-mix. CONCLUSIONS: Older patient age is independently associated with an increased risk of major postoperative complications after AAA repair. The increasing age of the United States population will compound this healthcare problem. Quality improvement efforts must focus on minimizing complication rates in elderly patients undergoing common vascular surgical procedures including AAA repair.

Age Distribution↗

Risk for stroke after elective noncarotid vascular surgery.

INTRODUCTION: Patients undergoing operations to treat peripheral vascular disease have systemic atherosclerosis and are at risk for stroke. However, the incidence and effect of cerebrovascular events on noncarotid vascular surgical outcomes are not well-defined. METHODS: Patients undergoing common operations for vascular disease from 1997 to 2000 were examined with data from the Veterans Affairs (VA) National Surgery Quality Improvement Project and the VA patient treatment files. Operations studied included abdominal aortic aneurysmectomy (n = 2551), aortobifemoral bypass (n = 2616), lower extremity bypass (n = 6866), and major lower extremity amputation (n = 7442). The incidence of perioperative stroke was determined, and logistic regression analysis was used to identify independent risk factors for stroke. Logistic and linear regression analyses were used to quantify the effect of postoperative stroke on adjusted mortality and length of stay. Odds ratio (OR) and 95% confidence interval (CI) were defined. P <.05 was considered significant. RESULTS: Stroke was uncommon after noncarotid vascular procedures, occurring in only 0.4% to 0.6% of patients. Independent risk factors for stroke include preoperative ventilation (OR, 11; 95% CI, 5.0-22.3; P <.001), previous stroke or transient ischemic attack (OR, 4.2; 95% CI, 2.7-6.4; P <.001), postoperative myocardial infarction (OR, 3.3; 95% CI, 1.3-8.7; P =.009), and need to return to the operating room (OR, 2.2; 95% CI, 1.4-3.5; P =.001). Factors that did not appear to be associated with stroke risk included procedure type, diabetes, renal failure, dialysis dependence, number of transfused units of blood, and hypertension. After controlling for other postoperative complications and comorbid conditions, postoperative stroke significantly increased the risk for perioperative mortality (OR, 6.3; 95% CI, 3.4-11.4; P <.001), with similar magnitude as postoperative myocardial infarction (OR, 6.3; 95% CI, 3.9-10.1; P <.001). Stroke was also associated with a 48% increase in overall length of stay. CONCLUSIONS: Stroke after noncarotid peripheral vascular surgery is uncommon, but results in markedly increased mortality and length of stay. Stroke risk is most strongly associated with previous stroke history and greater degree of illness. Patients with these associated conditions deserve particular attention to assessing and medically managing modifiable risk factors.

Aged↗

Patients undergoing infrainguinal bypass to treat atherosclerotic vascular disease are underprescribed cardioprotective medications: effect on graft patency, limb salvage, and mortality.

INTRODUCTION: Established American Heart Association guidelines recommend the use of statin drugs, angiotensin converting enzyme (ACE) inhibitors, and antiplatelet agents in patients with systemic atherosclerosis, such as those undergoing operative intervention to treat peripheral atherosclerotic disease. Many of these patients have not received treatment of coronary heart disease and have not been prescribed these medications. Whether statin drugs and ACE inhibitors confer an improvement in graft patency, limb salvage, and operative mortality is unknown. METHODS: Consecutive patients who underwent infrainguinal bypass between 1997 and 2002 were evaluated for demographic data, comorbid disease, medication use, as well as cumulative graft patency, limb salvage, and mortality. Univariate, multivariate logistical regression, and Kaplan-Meier analyses were performed. P <.05 was considered significant. RESULTS: Two hundred ninety-three patients (mean age, 64 years; 67% men) underwent 338 infrainguinal bypass procedures with autologous vein (n = 218), prosthetic grafts (n = 88), or composite prosthetic-vein grafts (n = 32). Limb salvage was the operative indication in 75% of procedures. Coexisting diseases included hypertension (70%), diabetes (52%), hyperlipidemia (37%), coronary heart disease (51%), congestive heart failure (14%), and active tobacco use (30%). Statin drugs were taken by 56% of patients, ACE inhibitors by 54% of patients, and antiplatelet agents or warfarin sodium (Coumadin) by 93% of patients. Postoperative graft surveillance was done in 39% of patients. Cumulative graft patency was 73%, limb salvage was 85%, and mortality was 9%, with a mean follow-up of 17 months. Factors independently associated with increased graft patency included statin drug use (odds ratio [OR], 3.7; 95% confidence interval [CI], 2.1-6.4), male sex (OR, 2.8; 95% CI, 1.6-5.0), and graft surveillance (OR, 2.4; 95% CI, 1.3-4.5). Factors associated with decreased amputation rate were statin drug use (OR, 0.34; 95% CI, 6.15-0.77) and graft surveillance (OR, 0.23; 95% CI, 6.1-0.63). Factors associated with decreased mortality included graft surveillance (OR, 0.18; 95% CI, 0.1-0.56), whereas congestive heart failure (OR, 6.5; 95% CI, 2.5-17) and hemodialysis-dependent renal failure (OR, 29; 95% CI, 6.1-140) were associated with increased mortality. Kaplan-Meier analysis showed that only ACE inhibitors were associated with lower mortality (P =.05) CONCLUSIONS: Patients undergoing infrainguinal bypass are undertreated with respect to cardioprotective medications. ACE inhibitor use is associated with lower mortality, and statin drug use is associated with improved graft patency and limb salvage. Institution of consensus guidelines concerning these medications should be considered by all vascular specialists, including vascular surgeons.

Angiotensin-Converting Enzyme Inhibitors↗

Diffusion of new technology for the treatment of renovascular hypertension in the United States: surgical revascularization versus catheter-based therapy, 1988-2001.

BACKGROUND: Trends in the management of renovascular hypertension were evaluated by using a representative national database to determine whether a shift in treatment technology and outcomes has occurred. METHODS: Clinical information regarding the treatment of renovascular hypertension in 5433 patients from 1988 to 2001 was derived from the Nationwide Inpatient Sample (NIS) database. Patients were classified into 3 groups: combined aortic and renal revascularization, isolated renal revascularization, and catheter-based procedures (angioplasty with or without stenting). Population-based trends were determined by using sampling weights for each year to estimate the total number of each intervention in the United States. Outcomes were compared using multivariate logistic regression analysis for risk-adjustment. RESULTS: A 73% decrease in combined aortic and renal revascularizations ( P = .033) and a 56% decrease in isolated renal revascularizations ( P < .001) occurred during the study period. Catheter-based procedures have increased 173% from 0.4 to 1.1 procedures per 100,000 adults during this same time period ( P < .001). Predictors favoring catheter-based treatment were admission acuity, increasing age, nonwhite race, and high socioeconomic status. Predictors of mortality for all 3 treatment groups included increasing age, emergent admission, and nonwhite race. CONCLUSIONS: A significant change in the management of patients with renovascular hypertension has occurred, with a shift towards less invasive catheter-based interventions. A better understanding of the diffusion of this technology in the treatment of individuals with renovascular hypertension will influence the training and distribution of future vascular specialists responsible for these patients.

Aged↗

Common celiacomesenteric trunk: aneurysmal and occlusive disease.

Eighteen patients (14 men, 4 women), ages 24 to 77 years, with a common celiacomesenteric trunk (CMT) were treated between 1965 and 2004 at the University of Michigan. Four patients had CMT aneurysmal or occlusive disease that led to operative treatment. Pertinent arteriographic findings in these 4 patients included a CMT aneurysm (n = 2), an occluded proximal CMT (n = 1), and a type III aortic dissection that was compressing the CMT (n = 1). Therapy in these 4 patients included placement of a polytetrafluoroethylene bypass graft from the supraceliac aorta to the CMT (n = 2) or a Dacron bypass graft from a thoracoabdominal bypass to the CMT (n = 1), and endovascular fenestration of the septum between the true and false lumens of an aortic dissection at the level of the CMT (n = 1).

Adult↗

Early MT-1 MMP expression following elastase exposure is associated with increased cleaved MMP-2 activity in experimental rodent aortic aneurysms.

OBJECTIVE: The objective of this study was to determine the significance of membrane type 1 matrix metalloproteinase (MT1-MMP) activation of MMP-2 in experimental abdominal aortic aneurysms. METHODS: Rat aortas were perfused with either saline as a control or elastase, and harvested on 2, 4, or 7 days after perfusion (n = 5 per treatment group/day). Aortic MT1-MMP and MMP-2 expression and protein were determined by real time polymerase chain reaction and Western blotting, respectively. Aortic explants were used to measure MMP-2 activity by zymography. Rat aortic smooth muscle cells in vitro were exposed to increasing doses of elastase and analyzed for MT-1 MMP expression. RESULTS: Aneurysms formed in 80% of the elastase-perfused aortas at 7 days, whereas none formed in the saline-perfused aortas. Significantly increased MT1-MMP expression was observed only on day 4, when levels were 6.5-fold higher in elastase-perfused aortas compared with saline-perfused aortas (P < .01). By day 7, MT1-MMP protein was present only in the elastase-perfused aortas (P = .02). By immunohistochemistry, MT1-MMP was detectable only in the elastase-perfused group at day 7. Cleaved MMP-2 activity (P = .045) was increased in elastase-perfused aortas compared with saline perfused aortas at day 7. In rat aortic smooth muscle cells, MT-1 MMP expression increased in response to elastase (P = .02). CONCLUSION: The rodent aortic aneurysm model exhibits upregulation of MT1-MMP expression and protein with subsequent increased conversion of MMP-2 from the latent to the cleaved form.

Animals↗

Diffusion of new technology in health care: the case of aorto-iliac occlusive disease.

BACKGROUND: The objective of the current study was to characterize temporal trends in the treatment of aorto-iliac occlusive disease (AIOD) and the impact of the introduction of less invasive therapy on overall intervention rates. METHODS: Patients with diagnostic codes for AIOD, and procedure codes for aortofemoral bypass (AFB) or iliac artery angioplasty and stenting were selected from the Nationwide Inpatient Sample for 1996 to 2000. Utilization rates of both intervention types were determined. Outcome variables including in-hospital mortality and duration of stay were assessed. RESULTS: The rate of iliac artery angioplasty and stenting increased 850%, from 0.4 to 3.4 cases per 100,000 adults (P <.001). The rate of AFB declined 15.5%, from 5.8 to 4.9 cases per 100,000 adults (P <.005). Older age, white race, and higher-income patients were more likely to undergo angioplasty and stenting. AFB had a higher mortality rate, longer duration of stay, and higher hospital charges compared to angioplasty and stenting. CONCLUSIONS: Iliac artery angioplasty and stenting has rapidly gained a large market share in the treatment of AIOD. Acceptable clinical outcomes have likely lowered the threshold for treatment and contributed to the rapid diffusion of this technology for the treatment of AIOD.

Aged↗

Increased MMP-9 expression and activity by aortic smooth muscle cells after nitric oxide synthase inhibition is associated with increased nuclear factor-kappaB and activator protein-1 activity.

OBJECTIVE: To determine the mechanism underlying increased expression and activity of matrix metalloproteinase 9 (MMP-9) by rat aortic smooth muscle cells (RA-SMC) after inhibition of inducible nitric oxide synthase (iNOS). METHODS AND RESULTS: Treatment of interleukin-1beta-stimulated RA-SMC with aminoguanidine led to an increase of 96% in MMP-9 activity (P = 0.003) by gelatin zymography, a 40% increase in pro-MMP-9 protein (P = 0.018) by Western blot, and a 155% increase in MMP-9 mRNA (P = 0.06) by reverse transcription polymerase chain reaction. Aminoguanidine also caused a 26% decrease in cytosolic IkappaB levels (P = 0.014) by Western blot, as well as a 97% increase in nuclear factor-kappaB binding and a 216% increase in activator protein-1 binding as measured by electrophoretic mobility shift assay. No significant changes were noted in MMP-2 or TIMP-1 expression, protein levels, or activity after aminoguanidine administration. CONCLUSIONS: MMP-9 expression and activity is increased in cytokine stimulated RA-SMCs after iNOS inhibition, coincident with activation of the nuclear factor-kappaB and activator protein-1 pathways. We speculate that local derangements in iNOS may favor MMP-9-dependent vessel wall damage in vivo via an inflammatory cascade mechanism.

Animals↗

American board of vascular surgery: the first 7 years.

The American Board of Vascular Surgery (ABVS) was incorporated in 1996 with a vision of improved training standards and certification of vascular surgeons. At that time, 91% of those holding American Board of Surgery Certificates of Added Qualifications in Vascular Surgery supported the formation of the ABVS. Subsequent events have led to a clear definition of specific educational issues important to the vascular surgery community. Unresolved issues relate to the need to complete a general surgery residency before beginning a vascular surgery fellowship, the continued inclusion of vascular surgery as a primary component of general surgery training, and the absence of a designated Residency Review Committee for Vascular Surgery. These issues have persisted since the inception of the ABVS. An application for the ABVS to become an American Board of Medical Specialties (ABMS) primary board was submitted in 2002 with a preliminary hearing before a liaison committee composed of American Medical Association and ABMS members. The American Board of Surgery (ABS) and a minority of the vascular surgery community vigorously opposed the application. The perceived divisiveness created by their actions contributed to the application's initial rejection and the necessity for an appeal. Certain ABS directors have recently stated that they would consider approving multiple track-type training that could allow single certification in vascular surgery, following 5 to 6 years of postgraduate training after medical school. The ABVS cautiously supports this action, recognizing that this radical change for the ABS may not be feasible given the broad-ranging interests of general surgery and restrictive ABMS guidelines for certifying medical specialists. The impact of not resolving the critical issues facing vascular surgery in a timely manner is that there will be inadequate numbers of competent vascular surgeons to provide for society's needs. An independent ABMS-approved ABVS provides a clear opportunity to resolve the recognized failings of the status quo.

Education, Medical, Graduate↗

Ultrasound measurement of aortic diameters in rodent models of aneurysm disease.

BACKGROUND: This investigation was undertaken to evaluate transabdominal ultrasound (US) measurements of aortic diameters in rats and mice as a complementary method to video microscopy (VM), the current standard for assessing the diameter of rodent aortas. METHODS: Aortic diameters were measured in 64 rats (n = 132 sets) and 12 mice (n = 36 sets) following experimental induction of aortic aneurysms. Diameters were measured at the renal vein, midinfrarenal aorta, and aortic bifurcation. RESULTS: In the rat, anteroposterior (AP) US measurements were closely correlated with transverse VM measurements, with correlation coefficients ranging from 0.66 to 0.77 (P < 0.0001) for axial US images and 0.58 to 0.63 (P < 0.0001) for sagittal US images. In the mouse, significant correlation coefficients were 0.57 (P < 0.001) near the renal vein and 0.44 (P = 0.007) at the midinfrarenal aorta. Aortic diameters increased significantly with increasing animal age and weight (R = 0.40, P = 0.003 at the renal vein, R = 0.29, P = 0.04 in the midinfrarenal aorta, and R = 0.39, P = 0.004 at the aortic bifurcation), suggesting that weight matched rodents must be used to define aortic dimensions in treatment groups as opposed to repeated comparisons with baseline measurements in a growing rat. CONCLUSION: Noninvasive aortic US measurements throughout the course of a rodent study of aneurysmal disease provide a practical alternative to VM for the repeated determinations of aortic diameters.

Animals↗

Variation in postoperative complication rates after high-risk surgery in the United States.

OBJECTIVE: Our goal was to characterize variation in complication rates across hospitals with differing volumes for select high-risk operations in the United States. METHODS: Data from the Nationwide Inpatient Sample for 1996 and 1997 were analyzed for 3 high-risk operations: esophagectomy (n=1,226), pancreatectomy (n=4,789), and intact abdominal aortic aneurysm repair (n=11,863). Complications evaluated included aspiration, cardiac complications, infection, pneumonia, pulmonary failure, renal failure, septicemia, and others. The risk of complications was calculated by hospital volume deciles, as well as for high-volume hospitals (HVH) and low-volume hospitals (LVH) defined by median hospital volume. RESULTS: Rates of any postoperative complication varied nearly 2-fold across hospital volume groups. The proportion of patients across hospital deciles having at least one complication ranged from 30% to 51% for esophageal resection, 6% to 12% for pancreatic resection, and 9% to 18% for abdominal aortic aneurysm repair. HVH had lower rates of one or more complications after pancreatic resection (OR, 0.71; 95% CI, 0.57 to 0.83; P=.002), esophageal resection (OR, 0.68; 95% CI, 0.52 to 0.90; P=.008), and intact abdominal aortic aneurysm (AAA) repair (OR, 0.67; 95% CI, 0.59 to 0.76; P<.001). Patients with one or more complications after pancreatic resection had a mortality of 18.8% versus only 5.2% for those without complications (P<.001). Esophageal resection mortality was 16.9% for patients with at least one complication and 2.5% for those without complications (P<.001) and AAA repair mortality was 10.4% for patients with at least one complication and 2.9% for those without complications (P<.001). CONCLUSIONS: High-risk operations have a decreased rate of postoperative complications when performed at HVH. Variation in complication rates may contribute to the volume-outcome relationship and provide a focus for quality improvement at LVH.

Aged↗