Long-term value in open and endovascular repair of chronic mesenteric ischemia

OBJECTIVE

Guidelines recommend open revascularization (OR) over endovascular revascularization (ER) for the treatment of chronic mesenteric ischemia (CMI) for younger, healthier patients. However, little is known about the long-term costs of these recommendations with respect to patients' overall life expectancy. This study investigated whether 5-year value differs between these treatment modalities.

METHODS

Patient data were extracted from the Statewide Planning and Research Cooperative System, the New York statewide all-payor database containing demographics, diagnoses, treatments, and charges. The database was queried for patients with an International Classification of Diseases, ninth revision, code for CMI, with the specific exclusion of acute ischemia cases. A propensity score match was performed using the Charlson Comorbidity Index, age, sex, race, renal status, and pulmonary disease for the final cohort of patients. Multiple linear regression and mixed effects linear regression were used to determine factors associated with 5-year value, calculated as life-years/$100k in charges. Charges were gathered from the index admission and subsequent admissions for acute or CMI, mesenteric angiography, or follow-up reintervention. Kaplan-Meier estimation was performed for survival and reintervention-free survival.

RESULTS

From 2000 to 2014, 875 patients underwent intervention for CMI. Of those meeting inclusion criteria, 209 (28.1%) underwent OR and 535 (71.9%) ER. After propensity score matching (n = 209 in each group), the ER group showed higher value at 5 years after the procedure (8.04 ± 11.42 life-years/$100k charges vs 4.89 ± 5.28 life-years/$100k charges; P < .01). More patients underwent reintervention in the ER group (37 patients vs 17 patients; P < .01), with 55 reinterventions in the ER group and 19 in the OR group (P < .01). Multiple linear regression analysis showed that age, congestive heart failure, dysrhythmia, cancer, and days spent in the intensive care unit were negatively associated with value at 5 years, whereas ER was positively associated. Survival was 59.6 ± 3.76% vs 62.3% ± 3.49% at 5 years (P = .91), and reintervention-free survival was 43.7 ± 3.86% vs 58.1 ± 3.53% (P = .04), for ER and OR respectively.

CONCLUSIONS

Despite increased reinterventions and lower reintervention-free survival, the value for patients with CMI was higher in those who underwent ER in the largest propensity score-matched cohort to date looking at long-term value. Factors negatively associated with value were OR, age, days in intensive care, congestive heart failure, dysrhythmia, and cancer. In patients with amenable anatomy, ER is validated as the first-choice treatment for CMI based on the superior procedural value.

Guideline Compliant Minimum Asymptomatic Carotid Endarterectomy Surgeon and Hospital Volume Cutoffs

BACKGROUND

There is a known association between volume and outcomes after carotid endarterectomy (CEA). A recent analysis suggested rates of stroke and death do not significantly reduce after a surgeon volume cutoff of 20 CEAs per year. However, these results would severely limit access. The objective here is to identify a lower optimal cutpoint for surgeon and hospital volume for asymptomatic CEA.

METHODS

We evaluated asymptomatic CEA patients using The New York Statewide Planning and Research Cooperative System database from 2000-2014. The relationship of 3-year averaged volumes for surgeons and hospitals to 30-day stroke was assessed using multiple logistic regression and included both hospital and surgeon volume in all analyses. Optimized cut points were the lowest significant volume cutoff that minimized the adjusted odds ratio of stroke.

RESULTS

We studied 32,549 CEAs performed by 271 surgeons in 136 centers by vascular surgeons. The median surgeon volume was 26.3 (interquartile range: 12.3-51.7) and the median hospital volume was 67 (interquartile range: 36.3-119.3). The surgeon volume cut point was 3 and the hospital volume cut point was 6 cases per year. There were 756 (2.3%) procedures performed by surgeons with a volume < 3 and 560 (1.7%) procedures performed by hospitals with a volume < 6. Perioperative stroke and death rates were 2.0% (95% confidence interval [CI]: 1.8-2.1) and 3.8% (95% CI: 2.6-5.5) for an average yearly surgeon volume ≥ 3 and < 3 (P = 0.070), respectively. The combined stroke and death rate was 2.0% (95% CI: 1.8-2.1) and 4.8% (95% CI: 3.2-7.0) for an average yearly center volume ≥ 6 and < 6 (P = 0.007), respectively. A combined surgeon and hospital volume variable also predicted outcomes and low-volume procedures did not meet previously proposed American Heart Association and Society for Vascular Surgery quality measures.

CONCLUSIONS

These data demonstrate an improvement in outcomes at a lower volume threshold than previously reported. These modest cutoff values should be used for asymptomatic CEA volume guideline formation and for future studies, after accounting for the impact of other important factors that may be driving volume-outcome relationships in asymptomatic CEA.

Limb shaking transient ischemic attack secondary to innominate artery stenosis

Limb shaking transient ischemic attack is a rare disease manifestation typically caused by carotid stenosis but rarely caused by flow-limiting lesions involving more proximal vasculature. We demonstrate a case of limb shaking transient ischemic attack secondary to innominate stenosis in a 69-year-old woman who presented after a left leg shaking spell that caused her to fall and fracture her ipsilateral tibia. She did not experience changes in mentation and did not show any evidence of a postictal period. After receiving a comprehensive workup, she successfully underwent revascularization with innominate artery stenting. Continuous retrograde aspiration with the Enroute system (Silk Road Medical) and carotid clamping were used for embolic protection.

Use of Glycoprotein IIb-IIIa Inhibitors in patients undergoing Carotid Artery Stenting in the Vascular Quality Initiative

OBJECTIVE

Antiplatelet therapies with thromboxane inhibitors and adenosine 5'-diphosphate (ADP) antagonists have been widely used following carotid artery stenting (CAS). However, these therapies may not apply to patients who are intolerant or present acutely. Glycoprotein IIb/IIIa inhibitors (GPI) are a proposed alternative therapy in these patients; however, their use has been limited due to concerns of increased risk for intracranial bleeding. Thus, this study aims to assess the safety profile of GPI in patients undergoing CAS.

METHOD

All patients undergoing CAS in the Society of Vascular Surgery - Vascular Quality Initiative database from 2012 to 2021 was included and grouped into GPI versus non-GPI therapy (control). The primary outcome was in-hospital stroke or death, and secondary outcomes included in-hospital stroke/transient ischemic attack (TIA), death, myocardial infarction (MI), and intracranial hemorrhage (ICH)/seizure. Patients were stratified by surgical approach (Transcarotid artery revascularization using flow reversal (TCAR) and transfemoral stenting (TF-CAS)), and stepwise backward logistic regression analysis was conducted to evaluate major primary and secondary outcomes.

RESULT

A total of 50,628 patients underwent carotid revascularization. Of these, 4.4% of the patients received GPI. Mean age (S.D.) was similar between control versus GPI (71.35(9.67) vs. 71.36(10.20) years). Compared to the control group, patients who receive GPI are less likely to be on optimal medical therapy, including aspirin (83.0% vs. 88.1%), P2Y12 inhibitor (73.0% vs 82.7%), and statin (82.3% vs. 86.0%)(All P<0.05). In addition, patients in the GPI group were more likely to undergo TCAR for carotid revascularization (52.2% vs. 48.4%) for emergent/urgent (29.4% vs. 16.8%) and symptomatic indications (55.5% vs. 49.7%) (All P<0.001). After stratifying by surgical approach, if patients underwent TFCAS and received a GPI, they were at increased odds of developing stroke/death (1.77(1.25-2.51)), death (OR(95% CI): 1.67(1.07-2.61)), stroke/TIA (OR (95% CI): 1.65(1.09-2.51)), and ICH/seizure (OR(95% CI): 2.13(1.23-3.68))(All P<0.05). No difference was seen in outcomes between the two groups if undergoing TCAR.

CONCLUSION

Patients who receive GPI were more likely to be symptomatic at presentation and less likely to be medically optimized before their carotid revascularization. Transfemoral access in patients receiving GPI was associated with increased odds of morbidity and mortality. However, this was not observed if undergoing TCAR. TCAR can be considered for its overall favorable results in high-risk patients who are not medically optimized.

Contrast-Associated Acute Kidney Injury in High-Risk Patients Undergoing Peripheral Vascular Interventions

Objective: This study aims to evaluate the use of prophylactic intravenous hydration (IV prophylaxis) and carbon dioxide (CO₂) angiography in reducing contrast associated-acute kidney injury (CA-AKI) and determine the overall incidence and risk factors of CA-AKI in high-risk patients undergoing peripheral vascular interventions (PVI). Method: Only patients undergoing elective PVI from 2017 to 2021 with chronic kidney disease (CKD) stage 3-5 in the Vascular Quality Initiative (VQI) database were included. Patients were grouped into IV prophylaxis vs no prophylaxis. The study's primary outcome was CA-AKI, defined as a rise in creatinine (>.5 mg/dL) or new dialysis within 48 hours following contrast administration. Standard univariate and multivariable (logistic regression) analyses were conducted. Results: A total of 4497 patients were identified. Of these, 65% received IV prophylaxis. The overall incidence of CA-AKI was .93%. No significant difference was seen in overall contrast volume (mean (SD): 66.89(49.54) vs 65.94(51.97) milliliters, P > .05) between the 2 groups. After adjusting for significant covariates, the use of IV prophylaxis (OR (95% CI): 1.54(.77-3.18), P = .25) and CO₂ angiography (OR (95%CI): .95(.44-2.08), P = .90) was not associated with a significant reduction in CA-AKI compared to the patients with no prophylaxis. The severity of CKD and diabetes were the only predictor of CA-AKI. Compared to patients with no CA-AKI, patients with CA-AKI were at risk of higher 30-day mortality (OR (95% CI): 11.09 (4.25-28.93)) and cardiopulmonary complications (OR (95% CI): 19.03 (8.74-41.39) following PVI (Both P < .001). Conclusion: Using a large national vascular database, our study demonstrates that prophylactic use of IV hydration and CO₂ angiography in high-risk CKD patients is not associated with a reduction in renal injury following PVI. Reduced kidney function and history of diabetes is an independent predictor of CA-AKI and patients that develop post-procedural AKI are at an increased risk of morbidity and mortality.

Gender Differences in Aortic Anatomic Severity Grade and Long-Term Survival Following Elective Abdominal Aortic Aneurysm Repair at a Single Tertiary Center

BACKGROUND

Anatomic severity grade (ASG) score is utilized to assess preoperative abdominal aortic aneurysms (AAA) and provide a quantitative data on its anatomic complexity. The aim of this study is to determine the anatomical differences and long-term survival between male and female patients undergoing elective AAA repair.

METHODS

All patients undergoing intact AAA repair from 2007 to 2014 were included. ASG scores were calculated based on preoperative anatomical characteristics including aortic neck, aneurysm, and iliac artery. Standard univariate analysis was used to evaluate patient and anatomical characteristics. Kaplan-Meier survival curves were used to evaluate long-term survival at 1 and 5 years.

RESULTS

A total of 379 patients were identified, of which, majority of them were males (80%). Females were on average 3 years older (mean [SD]: 74.32 [8.63] vs. 71.92 [8.64] years) and were more likely to undergo open repair (29.7% vs. 17.5%) (both P < 0.05). Both groups had similar comorbidities. The mean long-term follow-up (S.D.) was 6.21 (3.81) years. No significant difference was seen between males versus females in long-term survival at both 1 year (86.3% vs. 92.8, P = 0.06) and 5 year (68.5% vs. 72.7%, P = 0.38). In regard to the anatomical characteristics, females had shorter aortic neck length (mean in mm [S.D.]: 17.67 [1.41] vs. 27.20 [15.76]), increased tortuosity index [mean (S.D.): 1.11 (0.07) vs. 1.09 (0.07)]) and higher calcification [mean % (S.D.): 17.12 (21.17) vs. 10.59 (16.82)] (All P < 0.05). In contrast, males had larger aortic neck (mean in mm (S.D.): 23.81 (4.17) vs. 22.41 (4.16)] and iliac artery [mean in mm (S.D.): 7.70 (1.91) vs. 6.28 (1.67)] diameter (both P < 0.05). The mean total ASG score was significantly higher among females versus males [mean (S.D.): 17.23 (4.01) vs. 15.67 (3.96), P = 0.003]. After stratifying by ASG score ≥15, females had significantly lower survival at 1 year compared to males (82.6% vs. 92.1%, P = 0.04). However, this difference disappeared at 5 years.

CONCLUSIONS

The data demonstrate that females present at an older age with more complex AAA anatomy than males. Based on anatomical complexities, females were more likely to undergo open repair, with a corresponding increase in 1-year mortality, but not at 5 year. The data suggest that care processes for optimization of aortic surgery in females are needed to improve 1-year survival.

ACR Appropriateness Criteria® Radiologic Management of Mesenteric Ischemia: 2022 Update

Mesenteric ischemia is a serious medical condition characterized by insufficient vascular supply to the small bowel. In the acute setting, endovascular interventions, including embolectomy, transcatheter thrombolysis, and angioplasty with or without stent placement, are recommended as initial therapeutic options. For nonocclusive mesenteric ischemia, transarterial infusion of vasodilators, such as papaverine or prostaglandin E1, is the recommended initial treatment. In the chronic setting, endovascular means of revascularization, including angioplasty and stent placement, are generally recommend, with surgical options, such as bypass or endarterectomy, considered alternative options. Although the diagnosis of median arcuate ligament syndrome remains controversial, diagnostic angiography can be helpful in rendering a diagnosis, with the preferred treatment option being a surgical release. Systemic anticoagulation is recommended as initial therapy for venous mesenteric ischemia with acceptable rates of recanalization. If anticoagulation fails, transcatheter thrombolytic infusion can be considered with possible adjunctive placement of a transjugular intrahepatic portosystemic shunt to augment antegrade flow. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Impact of Routine Intracerebral Completion Angiography on Outcomes After TransCarotid Artery Revascularization

OBJECTIVES

Completion intracerebral angiography (CIA) following transcarotid artery revascularization (TCAR) aims to identify distal embolization after stenting and serve as a measure of intraoperative quality control. Nevertheless, there is no general evidence regarding the benefit of performing routine CIA. The aim of this study was to evaluate the potential risk and benefit of routine CIA.

METHODS

We retrospectively reviewed the Vascular Quality Initiative (VQI) database for transcarotid artery revascularization between 2016-2021. Patients were divided into two groups: patients with no CIA performed and those with completion angiography performed. The primary outcome was in-hospital stroke or death. Secondary outcomes included stroke, death, myocardial infarction (MI) and return to the operating room (RTOR). Clinically relevant and statistically significantly variables on univariable analysis were added to a logistic regression model clustered by center identifier.

RESULTS

A total of 18,155 patients who underwent TCAR were identified, 63.7% of them had routine CIA performed. Patients who had routine CIA were more likely to have contralateral carotid occlusion and general anesthesia. After adjusting for potential confounders, we found no difference in the risk of stroke or death (aOR): 1.03, 95%CI (0.8-1.3), P=.820), stroke/TIA (aOR, 1, 95%CI (0.8-1.3), P=.998), stroke (aOR: 1.1, 95%CI (0.8-1.4), P=.452), death (aOR: 0.98, 95%CI (0.6-1.6), P=.953), MI (aOR: 0.78, 95%CI (0.5-1.2), P=.240), or RTOR (aOR: 1.5, 95%CI (0.6-3.8), P=.412) between patients who had CIA compared to those who did not. A sub-analysis of patients who had new occlusion detected on CIA (69 patients, 0.6%; 19 not treated and 50 treated) indicated higher risk of stroke or death in patients with treated new occlusions (OR: 7.1, 95%CI (2.9-17.3), P<.001) and stroke/TIA (aOR, 5.8, 95%CI (2.3-14.7), P<.001) compared to patients who had no CIA. However, no difference in stroke/death (OR: 3.3, 95%CI (0.37-29.5), P=.283) or stroke/TIA (aOR, 3.1, 95%CI (0.3-29.4), P=.327) was found in patients with non-treated new occlusions compared to patients who had no CIA.

CONCLUSIONS

In this retrospective study, routine performance of completion cerebral angiography was not beneficial with no significant differences in in-hospital stroke or death detected. Detection of new lesions on completion cerebral angiography was rare. Moreover, identifying new occlusions following intracranial angiography was associated with higher odds of stroke or death when these new lesions are treated. Further studies are needed to define the etiology of worse outcomes in patients undergoing intervention for lesions discovered on completion cerebral angiogram and delineate optimal timing for further imaging and intervention.

Surgeon volume and established hospital perioperative mortality rate together predict for superior outcomes after open abdominal aortic aneurysm repair

BACKGROUND

In 2018, the Society for Vascular Surgery (SVS) published hospital volume guidelines for elective open abdominal aortic aneurysm (AAA) repair, recommending that elective open surgical repair of AAAs should be performed at centers with an annual volume of ≥10 open aortic operations of any type and a documented perioperative mortality of ≤5%. Recent work has suggested a yearly surgeon volume of at least seven open aortic cases for improved outcomes. The objective of the present study was to assess the importance of hospital volume and surgeon volume at these cut points for predicting 1-year mortality after open surgical repair of AAAs.

METHODS

We evaluated patients who had undergone elective open AAA repair using the New York Statewide Planning and Research Cooperative System database from 2003 to 2014. The effect of the SVS guidelines on postoperative mortality and complications was evaluated. Confounding between the hospital and surgeon volumes was identified using mixed effects multivariate Cox proportional hazards analysis. The effect of the interactions between hospital volume, established hospital perioperative survival, and surgeon volume on postoperative outcomes was also investigated.

RESULTS

The cohort consisted of 7594 elective open AAA repairs performed by 542 surgeons in 137 hospitals during the 12-year study period. Analysis of the 2018 guidelines using the Statewide Planning and Research Cooperative System database revealed 1-year and 30-day mortality rates of 9.2% (range, 8.3%-10.1%) and 3.5% (range, 2.9%-4.1%) for centers that were within the SVS guidelines and 13.6% (range, 12.5%-14.7%) and 6.9% (range, 6.1%-7.8%) for those that were outside the guidelines, respectively (P < .001 for both). Multivariate survival analysis revealed a hazard ratio for a surgeon volume of ≥7, hospital volume of ≥10, and hospital 3-year perioperative mortality of ≤5% of 0.80 (95% confidence interval [CI], 0.70-0.93; P = .003), 0.91 (95% CI, 0.77-1.08; P = .298), and 0.72 (95% CI, 0.62-0.82; P < .001), respectively. Additionally, procedures performed by surgeons with a yearly average volume of open aortic operations of at least seven and at hospitals with an established elective open AAA repair perioperative mortality rate of ≤5% showed improved 1-year (33.2% relative risk reduction; P < .001) and 30-day (P = .001) all-cause survival and improved postoperative complication rates.

CONCLUSIONS

These data have demonstrated that centers that meet the SVS AAA volume guidelines are associated with improved 1-year and 30-day all-cause survival. However, the results were confounded by surgeon volume. A surgeon open aortic volume of at least seven procedures and an established hospital perioperative mortality of ≤5% each independently predicted for 1-year survival after open AAA repair, with the hospital volume less important. These results indicate that surgeons with an annual volume of at least seven open aortic operations of any type should perform elective open AAA repair at centers with a documented perioperative mortality of ≤5%.

Use of antitussive medications in acute cough in young children

Acute cough, a common complaint in young children, is often the result of a viral upper respiratory infection. Cough and cold remedies generate billions of dollars in annual sales in the United States, despite a lack of evidence of their efficacy and multiple warnings by the US Food and Drug Administration. The current article begins with the best available evidence for common over-the-counter (OTC) and prescription antitussive remedies in children. The article concludes with a discussion of the pros and cons for the use of antitussives in children with cough. In general, OTC antitussive medications should not be routinely used in children under 2 years of age. In certain cases, antitussives with minimal adverse profile and some evidence of benefit may be recommended after informed counseling.

Safety and effectiveness of the TREO stent graft for the endovascular treatment of abdominal aortic aneurysms

OBJECTIVE

The short- and mid-term outcomes of endovascular aortic aneurysm repair have made it a standard treatment of abdominal aortic aneurysms. However, newer generation devices have yet to demonstrate improved long-term rates for complications, reinterventions, and survival. The TREO stent graft is a latest generation device and was evaluated for approval in the United States.

METHODS

In a multicenter, nonrandomized, investigational device exemption clinical trial, we assessed the safety and effectiveness of the TREO device, with core laboratory assessment of the imaging studies and an independent adjudication of safety. The primary effectiveness endpoint was successful aneurysm treatment at 1 year. The primary safety endpoint was the incidence of major adverse events (MAE) at 30 days.

RESULTS

A total of 150 patients (132 men; 88.0%) with infrarenal abdominal aortic (87.3%) or aortoiliac (12.7%) aneurysms were enrolled. The data were normally distributed. The mean age was 71.7 ± 7.4 years. The MAE incidence at 30 days was 0.7%. One subject experienced two MAE: myocardial infarction and procedural blood loss of 1000 mL. The proportion of successful aneurysm treatment at 1 year was 93.1%. Longer term follow-up continues, with no aneurysm-related mortality at the latest follow-up. At 3 years, the cumulative all-cause mortality and incidence of type I and type III endoleaks was 10.7% (n = 16), 2.7% (n = 4), and 0% (n = 0), respectively. In addition, aneurysm sac shrinkage >5 mm at 3 years had occurred in 54.3% of patients, and 9.3% had required a secondary intervention (n = 14).

CONCLUSIONS

The safety and effectiveness of endovascular repair of abdominal aneurysms with TREO were demonstrated, with 93.1% successful aneurysm treatment at 1 year and aneurysm sac shrinkage >5 mm at 3 years in 54.3% of patients. Long-term follow-up continues to determine whether these favorable outcomes will be sustained.

Etiology and Outcomes of Spinal Cord Infarct: A Case Series From a Level 1 Trauma Center

STUDY DESIGN

Retrospective study.

OBJECTIVES

To evaluate the demographics, prevalence, etiology, severity, and outcomes of spinal cord injuries (SCIs) resulting from ischemic infarction.

METHODS

All patients with SCI and a diagnosis of cord infarct who were admitted to the inpatient rehabilitation unit at a level 1 trauma center from January 2003 to January 2014 were identified using an administrative billing database. Outcomes measures were evaluated.

RESULTS

Among 685 unique SCI patients who were identified, 30 (4.4%) had SCI due to spinal ischemic infarction. The mean age was 59 years (range 17-80 years). Fifty percent of patients had ASIA (American Spinal Injury Association) A and B severity. Most common causes were the following: 6 (20%) abdominal aortic aneurysm (AAA) repairs, 6 (20%) arteriovenous fistulas, and 6 (20%) with an unknown cause. Surgical complications led to 4 (13.3%) cord infarcts and was associated with a higher severity of injury (P = .02) compared with other etiologies. Other causes included systemic hypotension, AAA rupture, trauma, diabetic ketoacidosis, and after radiation therapy. At follow-up, 6 (20%) of patients were able to ambulate normally without assistance, 7 (23.3%) were ambulating with assistance, and 17 (56.7%) were still wheelchair bound. Clinical improvement in ambulatory status was noted in 6 (20%) patients and was associated with less severe initial injury (P = .02).

CONCLUSIONS

While the existing literature associates spinal cord infarction with aortic pathologies and surgery, these caused less than 30% of cases, while nonaortic surgical complications were associated with the most severe injuries. Outcomes were worse than previously reported in the literature.

One-year patient survival correlates with surgeon volume after elective open abdominal aortic surgery

OBJECTIVE

Volume-outcome relationships in surgery have been well established. Studies have shown that high-volume surgeons provide improved outcomes in performing open abdominal aneurysm repairs. The hypothesis of this study was that high-volume surgeons provide superior short-term and midterm outcomes of elective open aortic operations compared with low-volume surgeons.

METHODS

We evaluated patients undergoing elective open abdominal aortic aneurysm repair, aortofemoral bypass, and aortomesenteric bypass by board-certified vascular surgeons using the New York Statewide Planning and Research Cooperative System database from 2002 to 2014. The Contal and O'Quigley technique was used to estimate a cut point objectively and provided an estimate of significance. A division using average yearly volumes (averaged during 3 years) of seven or more cases and fewer than seven cases per year returned the highest Q statistic, and this grouping was used to classify high-volume and low-volume provider groups. Rates of complications during index hospitalization, length of stay, 30-day survival, 90-day survival, 1-year survival, and cause of death were analyzed using mixed effect models.

RESULTS

In 118 hospitals during the 13-year period, 266 board-certified vascular surgeons performed 244 aortomesenteric bypasses, 4202 aortofemoral bypasses, and 6126 abdominal aortic aneurysm repairs. High-volume surgeons' rates of complications during index hospitalization, 30-day survival, 90-day survival, and 1-year survival were superior to those of low-volume surgeons. The Contal and O'Quigley technique returned an estimate of seven operations per year for optimal survival during 1 year. This cutoff is associated with an adjusted 1-year hazard ratio of 0.687 (P = .003), a 2.69% difference in 1-year all-cause survival (P = .003), and a 1.76-day reduction in the mean length of stay at index hospitalization (P < .001). Higher volume surgeons showed a 25.0%, 43.4%, 42.4%, 40.6%, and 45.0% reduction in postoperative rates of acute renal failure (P < .001), hemorrhage (P < .001), pulmonary failure (P < .001), sepsis (P < .001), and venous thromboembolism (P < .001), respectively. Abdominal abscess, acute renal failure, hemorrhage, myocardial infarction, and sepsis were associated with increased cardiovascular cause-specific mortality after open aortic operations (P < .001).

CONCLUSIONS

These data demonstrate that high-volume surgeons performing elective open aortic operations provide reduced complications and improved short-term and midterm survival compared with low-volume surgeons. Clinical and postoperative variables that are associated with increased cardiovascular cause-specific mortality are also identified. These data provide further evidence that elective open abdominal vascular surgery should be centralized to high-volume surgeons.

Development of a Whole-Task Simulator for Carotid Endarterectomy

BACKGROUND

Surgical education relies on operative exposure with live patients. Carotid endarterectomy (CEA) demands an experienced surgeon with a very low complication rate. The high-risk nature of this procedure and the decline in number of CEAs performed annually has created a gap in residency training.

OBJECTIVE

To develop a high-fidelity whole-task simulation for CEA that demonstrates content, construct, and face validity.

METHODS

Anatomically accurate models of the human neck were created using multilayered poly-vinyl alcohol hydrogels. Graded polymerization of the hydrogel was achieved by inducing crosslinks during freeze/thaw cycles, stiffening the simulated tissues to achieve realistic tactile properties. Venous bleeding was simulated using pressure bags and a ventricular assistive device created pulsatile flow in the carotid. Ten surgeons performed the simulation under operating room conditions, and metrics were compared among experience levels to determine construct validity. Participants completed surveys about realism and usefulness to evaluate face validity.

RESULTS

A significant difference was found in operative measures between attending and resident physicians. The mean operative time for the expert group was 63.6 min vs 138.8 for the resident group (P = .002). There was a difference in mean internal carotid artery clamp time of 43.4 vs 83.2 min (P = .04). There were only 2 hypoglossal nerve injuries, both in the resident group (P = .009).

CONCLUSION

The whole-task CEA simulator is a realistic, inexpensive model that offers comprehensive training and allows residents to master skills prior to operating on live patients. Overall, the model demonstrated face and construct validity among neurosurgery and vascular surgeons.

Abstract 560: Differences in GCN5L1 Expression Between Male and Female Hearts Are Associated With Increased Mitochondrial Protein Acetylation

Introduction: Historically, most preclinical heart research has relied predominantly on male subjects, despite the identification of significant differences in signaling, metabolism, and pathology between males and females. Delineating the mechanisms behind these sex differences is critical to the effective application of novel findings to the general population as a whole. GCN5L1 is a mitochondrial-targeted protein that drives the acetylation and activation/deactivation of several metabolic proteins, and which has recently been reported to regulate cardiac metabolism and recovery from ischemia-reperfusion. It is unknown whether GCN5L1 plays a role in sex-specific differences in the myocardium.

Hypothesis: Differential regulation of myocardial GCN5L1 expression between male and female animals results in differences in the acetylation and activity of proteins that regulate glucose and fatty acid oxidation.

Methods: Heart lysates from male and female mice were probed for the expression of GCN5L1, and the acetylation status of whole cell and mitochondrial protein fractions was analyzed. Proliferating cardiac cells were treated with 17β-estradiol, and the expression of GCN5L1 was evaluated by immunoblotting. The acetylation status of mitochondrial proteins was measured using immunoblotting and immunoprecipitation.

Results and Conclusions: Significant differences in cardiac GCN5L1 protein expression were found between male and female mice. In contrast, there was no difference in the protein expression of SIRT3, the mitochondrial deacetylase enzyme previously shown to counter GCN5L1 activity. Mitochondrial acetylation levels were found to be different between male and female mice. Treatment of cardiac cells with estradiol resulted in increased GCN5L1 expression, with a concurrent increase in the acetylation status of GCN5L1 targets localized to mitochondria. We conclude that sex-based differences in mitochondrial protein acetylation may be mediated by hormone-induced changes in GCN5L1 expression.

Publishing peer review materials

Publishing peer review materials alongside research articles promises to make the peer review process more transparent as well as making it easier to recognise these contributions and give credit to peer reviewers. Traditionally, the peer review reports, editors letters and author responses are only shared between the small number of people in those roles prior to publication, but there is a growing interest in making some or all of these materials available. A small number of journals have been publishing peer review materials for some time, others have begun this practice more recently, and significantly more are now considering how they might begin. This article outlines the outcomes from a recent workshop among journals with experience in publishing peer review materials, in which the specific operation of these workflows, and the challenges, were discussed. Here, we provide a draft as to how to represent these materials in the JATS and Crossref data models to facilitate the coordination and discoverability of peer review materials, and seek feedback on these initial recommendations.

Pediatric Readiness in the Emergency Department

This is a revision of the previous joint Policy Statement titled "Guidelines for Care of Children in the Emergency Department." Children have unique physical and psychosocial needs that are heightened in the setting of serious or life-threatening emergencies. The majority of children who are ill and injured are brought to community hospital emergency departments (EDs) by virtue of proximity. It is therefore imperative that all EDs have the appropriate resources (medications, equipment, policies, and education) and capable staff to provide effective emergency care for children. In this Policy Statement, we outline the resources necessary for EDs to stand ready to care for children of all ages. These recommendations are consistent with the recommendations of the Institute of Medicine (now called the National Academy of Medicine) in its report "The Future of Emergency Care in the US Health System." Although resources within emergency and trauma care systems vary locally, regionally, and nationally, it is essential that ED staff, administrators, and medical directors seek to meet or exceed these recommendations to ensure that high-quality emergency care is available for all children. These updated recommendations are intended to serve as a resource for clinical and administrative leadership in EDs as they strive to improve their readiness for children of all ages.

Pediatric Medication Safety in the Emergency Department

Pediatric patients cared for in emergency departments (EDs) are at high risk of medication errors for a variety of reasons. A multidisciplinary panel was convened by the Emergency Medical Services for Children program and the American Academy of Pediatrics Committee on Pediatric Emergency Medicine to initiate a discussion on medication safety in the ED. Top opportunities identified to improve medication safety include using kilogram-only weight-based dosing, optimizing computerized physician order entry by using clinical decision support, developing a standard formulary for pediatric patients while limiting variability of medication concentrations, using pharmacist support within EDs, enhancing training of medical professionals, systematizing the dispensing and administration of medications within the ED, and addressing challenges for home medication administration before discharge.

Vascular surgeon-hospitalist comanagement improves in-hospital mortality at the expense of increased in-hospital cost

OBJECTIVE

We have shown that vascular surgeon- hospitalist co management resulted in improved in-hospital mortality rates. We now aim to assess the impact of the hospitalist co management service (HCS) on healthcare cost.

METHODS

A total of 1558 patients were divided into three cohorts and compared: 516 in 2012, 525 in 2013, and 517 in 2014. The HCS began in January 2013. Data were standardized for six vascular surgeons that were present 2012-2014. New attendings were excluded. Ten hospitalists participated. Case mix index (CMI), contribution margin, total hospital charges (THCs), length of stay (LOS), actual direct costs (ADCs), and actual variable indirect costs (AVICs) were compared. Analysis of variance with post-hoc tests, t-tests, and linear regressions were performed.

RESULTS

THC rose by a mean difference of $14,578.31 between 2012 and 2014 (P < .001) with a significant difference found between all groups during the study period (P = .0004). ADC increased more than AVIC; however, both significantly increased over time (P = .0002 and P = .014, respectively). A mean $3326.63 increase in ADC was observed from 2012 to 2014 (P < .0001). AVIC only increased by an average $392.86 during the study period (P = .01). This increased cost was observed in the context of a higher CMI and longer LOS. CMI increased from 2.25 in 2012 to 2.53 in 2014 (P = .006). LOS increased by a mean 1.02 days between 2012 and 2014 (P = .016), and significantly during the study period overall (P = .018). After adjusting for CMI, LOS increases by only 0.61 days between 2012 and 2014 (P = .07). In a final regression model, THC is independently predicted by comanagement, CMI, and LOS. After adjusting for CMI and LOS, the increase in THC because of comanagement (2012 vs 2014) accounts for only $4073.08 of the total increase (P < .001). During this time, 30-day readmission rates decreased by ∼7% (P = .005), while related 30-day readmission rates decreased by ∼2% (P = .32). Physician contribution margin remained unchanged over the 3-year period (P = .76). The most prevalent diagnosis-related group was consistent across all years. Variation in the principal diagnosis code was observed with the prevalence of circulatory disorders because of type II diabetes replacing atherosclerosis with gangrene as the most prevalent diagnosis in 2013 and 2014 compared with 2012.

CONCLUSIONS

In-hospital cost is significantly higher since the start of the HCS. This surge may relate to increased CMI, LOS, and improved coding. This increase in cost may be justified as we have observed sustained reduction in in-hospital mortality and slightly improved readmission rates.

Endovascular Stent Exclusion of a Hepatic Artery Pseudoaneurysm

Presented is a patient with an iatrogenic hepatic artery pseudoaneurysm that was treated by endovascular stent grafting. Endovascular stent grafting of a hepatic artery pseudoaneurysm offers a safe and potentially less morbid alternative to an open repair. The report stresses the necessity of careful preoperative evaluation with angiography to determine the feasibility of the procedure. An aggressive approach to treating hepatic artery pseudoaneurysms is advocated because of the poor correlation between size and their tendency to rupture. With an increasing rate of diagnosis of visceral artery aneurysms in elderly, debilitated patients, endovascular repair is anticipated to have an increasing role and should be considered a first-line therapy in anatomically suitable candidates.

Renal-splanchnic steal syndrome: the treatment of chronic mesenteric ischemia with renal angioplasty and stenting

The clinical syndrome of chronic mesenteric ischemia classically presents with a combination of involuntary weight loss, post prandial abdominal pain, and food fear. With occlusion or stenosis of the celiac and superior mesenteric arteries (SMA) collateral blood flow between mesenteric vessels is common and frequently act as the sole blood supply to the intestine. We present a rare case of chronic mesenteric ischemia in which the main blood supply to the celiac and SMA were collaterals coming off the right renal artery resulting in renal-splachnic steal. After an unsuccessful attempt to cannulate the SMA and celiac vessels it was possible to relieve this patient's symptoms with renal artery stenting.

Evolution of bacterial arteritis into a mycotic aortic aneurysm

Arteritis and mycotic aneurysms have been well described for more than 100 years. The authors report a case of bacterial arteritis that presented with pneumatosis of the aortic wall and that evolved over 1 week into an infected abdominal aortic aneurysm. This case documents the rapid progression from arteritis to mycotic aneurysm, highlighting the need for close radiologic follow-up and aggressive medical and surgical management.

Stapled versus sutured gastrointestinal anastomoses in the trauma patient: a multicenter trial

BACKGROUND

Construction of gastrointestinal anastomoses utilizing stapling devices has become a familiar procedure. In elective surgery, studies have shown no significant differences in complications between stapled and sutured anastomoses. Controversy has recently arisen regarding the accurate incidence of complications associated with anastomoses in the trauma patient. The objective of this multi-institutional study was to determine whether the incidence of postoperative complications differs between stapled and sutured anastomoses following the emergent repair of traumatic bowel injuries.

METHODS

Using a retrospective cohort design, all trauma registry records from five Level I trauma centers over a period of 4 years were reviewed.

RESULTS

A total of 199 patients with 289 anastomoses were identified. A surgical stapling device was used to create 175 separate anastomoses, while a hand-sutured method was employed in 114 anastomoses. A complication was defined as an anastomotic leak verified at reoperation, an intra-abdominal abscess, or an enterocutaneous fistula. The mean abdominal Abbreviated Injury Scale score and Injury Severity Score were similar in the two cohort groups. Stapling and suturing techniques were evenly distributed in both small and large bowel repairs. Seven of the total 175 stapled anastomoses and none of the 114 hand-sewn anastomoses resulted in a clinically significant leak requiring reoperation (RR = undefined, 95% CI 1.08-infinity, p = 0.04). Each anastomotic leak occurred in a separate individual. Nineteen stapled anastomoses and four sutured anastomoses were associated with an intra-abdominal abscess (RR = 2.7, 95% CI 0.96-7.57, p = 0.04). Enterocutaneous fistula formation was not statistically associated with either type of anastomoses (stapled cohort = 3 of 175 and sutured cohort = 2 of 114). Overall, 22 (13%) stapled anastomoses and 6 (5%) sutured anastomoses were associated with an intra-abdominal complication (RR = 2.08, 95% CI 0.89-4.86, p = 0.076).

CONCLUSION

Anastomotic leaks and intra-abdominal abscesses appear to be more likely with stapled bowel repairs compared with sutured anastomoses in the injured patient. Caution should be exercised in deciding to staple a bowel anastomosis in the trauma patient.

Differential activation of wild-type and variant forms of estrogen receptor alpha by synthetic and natural estrogenic compounds using a promoter containing three estrogen-responsive elements

Structure-dependent estrogen receptor alpha (ER alpha) agonist and antagonist activities of synthetic and natural estrogenic compounds were investigated in human HepG2, MDA-MB-231 and U2 cancer cell lines. Compounds used in this study include 4'-hydroxytamoxifen, ICI 182,780, bisphenol-A (BPA), 2',4',6'-trichloro-4-biphenylol (3Cl-PCB-OH), 2',3',4',5'-tetrachloro-4-biphenylol (4Cl-PCB-OH), p-t-octylphenol, p-nonylphenol, naringenin, kepone, resveratrol, and 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE). Cells were transfected with a construct (pERE(3)) containing three tandem estrogen responsive elements (EREs) and either wild-type estrogen receptor alpha (ER-wt) or variants expressing activation function-1 (ER-AF1) or AF-2 (ER-AF2). The ER agonist activities of the synthetic mono and dihydroxy aromatic compounds are comparable in all three-cell lines, whereas the activities of naringenin, kepone and resveratrol are dependent on cell context and expression of wild-type or variant forms of ER alpha. In contrast, the ER antagonist activities for these compounds were highly complex and, with the exception of 3Cl-PCB-OH, all compounds inhibited E2-induced wild-type or variant ER action. Results of this in vitro study suggest that the estrogenic and antiestrogenic activity of structurally diverse synthetic and natural estrogenic compounds is complex, and this is consistent with published data that often give contradictory results for these compounds.

Transcriptional activation of deoxyribonucleic acid polymerase alpha gene expression in MCF-7 cells by 17 beta-estradiol

Treatment of MCF-7 human breast cancer cells with 17beta-estradiol (E(2)) results in increased DNA synthesis and cell proliferation and enhanced enzyme activities associated with purine/pyrimidine biosynthesis. The mechanism of enhanced DNA polymerase alpha activity was investigated by analysis of the promoter region of this gene. E(2) induced luciferase (reporter gene) activity in MCF-7 cells transfected with pDNAP1, pDNAP2, and pDNAP3 containing -1515 to +45, -248 to +45 and -116 to +45 inserts from the DNA polymerase alpha gene promoter, whereas no induction was observed with pDNAP4 (-65 to +45 insert). The induction response was dependent on cotransfection with estrogen receptor alpha (ER(alpha)), and transactivation was also observed with a mutant ER(alpha) that did not express the DNA-binding domain. Subsequent functional, DNA binding, and DNA footprinting studies showed that a GC-rich region at -106 to -100 was required for E(2)-mediated transactivation, and Sp1 protein, but not ER(alpha), bound this sequence. Transcriptional activation of DNA polymerase alpha by E(2) is associated with ER(alpha)/Sp1 action at a proximal GC-rich promoter sequence, and this gene is among a growing list of E(2)-responsive genes that are induced via ER(alpha)/Sp1 protein interactions that do not require direct binding of the hormone receptor to DNA.

Penetrating esophageal injuries: multicenter study of the American Association for the Surgery of Trauma

OBJECTIVE

The purpose of this study was to define the period of time after which delays in management incurred by investigations cause increased morbidity and mortality. The outcome study is intended to correlate time with death from esophageal causes, overall complications, esophageal related complications, and surgical intensive care unit length of stay.

METHODS

This was a retrospective multicenter study involving 34 trauma centers in the United States, under the auspices of the American Association for the Surgery of Trauma Multi-institutional Trials Committee over a span of 10.5 years. Patients surviving to reach the operating room (OR) were divided into two groups: those that underwent diagnostic studies to identify their injuries (preoperative evaluation group) and those that went immediately to the OR (no preoperative evaluation group). Statistical methods included Fisher's exact test, Student's T test, and logistic regression analysis.

RESULTS

The study involved 405 patients: 355 male patients (86.5%) and 50 female patients (13.5%). The mean Revised Trauma Score was 6.3, the mean Injury Severity Score was 28, and the mean time interval to the OR was 6.5 hours. There were associated injuries in 356 patients (88%), and an overall complication rate of 53.5%. Overall mortality was 78 of 405 (19%). Three hundred forty-six patients survived to reach the OR: 171 in the preoperative evaluation group and 175 in the no preoperative evaluation group. No statistically significant differences were noted in the two groups in the following parameters: number of patients, age, Injury Severity Score, admission blood pressure, anatomic location of injury (cervical or thoracic), surgical management (primary repair, resection and anastomosis, resection and diversion, flaps), number of associated injuries, and mortality. Average length of time to the OR was 13 hours in the preoperative evaluation group versus 1 hour in the no preoperative evaluation group (p < 0.001). Overall complications occurred in 134 in the preoperative evaluation group versus 87 in the no preoperative evaluation group (p < 0.001), and 74 (41%) esophageal related complications occurred in the preoperative evaluation group versus 32 (19%) in the no preoperative evaluation group (p = 0.003). Mean surgical intensive care unit length of stay was 11 days in the preoperative evaluation group versus 7 days in the no preoperative evaluation group (p = 0.012). Logistic regression analysis identified as independent risk factors for the development of esophageal related complications included time delays in preoperative evaluation (odds ratio, 3.13), American Association for the Surgery of Trauma Organ Injury Scale grade >2 (odds ratio, 2.62), and resection and diversion (odds ratio, 4.47).

CONCLUSION

Esophageal injuries carry a high morbidity and mortality. Increased esophageal related morbidity occurs with the diagnostic workup and its inherent delay in operative repair of these injuries. For centers practicing selective management of penetrating neck injuries and transmediastinal gunshot wounds, rapid diagnosis and definitive repair should be made a high priority.

Crosstalk between estrogen receptor alpha and the aryl hydrocarbon receptor in breast cancer cells involves unidirectional activation of proteasomes

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental toxin that activates the aryl hydrocarbon receptor (AhR) and disrupts multiple endocrine signaling pathways. T47D human breast cancer cells express a functional estrogen receptor alpha (ERalpha) and AhR, and treatment of these cells with 17beta-estradiol (E2) or TCDD resulted in a rapid proteasome-dependent decrease in immunoreactive ERalpha and AhR proteins (>60-80%), respectively. E2 did not affect the AhR, whereas TCDD induced proteasome-dependent degradation of both the AhR and ERalpha in T47D and MCF-7 human breast cancer cells, and these responses were specifically blocked by proteasome inhibitors. Thus, TCDD-induced degradation of ERalpha may contribute to the antiestrogenic activity of AhR agonists and this pathway may be involved in AhR-mediated disruption of other endocrine responses.

Inhibition of vascular endothelial growth factor expression in HEC1A endometrial cancer cells through interactions of estrogen receptor alpha and Sp3 proteins

Treatment of HEC1A endometrial cancer cells with 10 nm 17beta-estradiol (E2) resulted in decreased vascular endothelial growth factor (VEGF) mRNA expression, and a similar response was observed using a construct, pVEGF1, containing a VEGF gene promoter insert from -2018 to +50. In HEC1A cells transiently transfected with pVEGF1 and a series of deletion plasmids, it was shown that E2-dependent down-regulation was dependent on wild-type estrogen receptor alpha (ERalpha) and reversed by the anti-estrogen ICI 182, 780, and this response was not affected by progestins. Deletion analysis of the VEGF gene promoter identified an overlapping G/GC-rich site between -66 to -47 that was required for decreased transactivation by E2. Protein-DNA binding studies using electrophoretic mobility shift and DNA footprinting assays showed that both Sp1 and Sp3 proteins bound this region of the VEGF promoter. Coimmunoprecipitation and pull-down assays demonstrated that Sp3 and ERalpha proteins physically interact, and the interacting domains of both proteins are different from those previously observed for interactions between Sp1 and ERalpha proteins. Using a dominant negative form of Sp3 and transcriptional activation assays in Schneider SL-2 insect cells, it was confirmed that ERalpha-Sp3 interactions define a pathway for E2-mediated inhibition of gene expression, and this represents a new mechanism for decreased gene expression by E2.