Factors associated with successful median arcuate ligament release in an international, multi-institutional cohort.

OBJECTIVE: Prior research on median arcuate ligament syndrome has been limited to institutional case series, making the optimal approach to median arcuate ligament release (MALR) and resulting outcomes unclear. In the present study, we compared the outcomes of different approaches to MALR and determined the predictors of long-term treatment failure. METHODS: The Vascular Low Frequency Disease Consortium is an international, multi-institutional research consortium. Data on open, laparoscopic, and robotic MALR performed from 2000 to 2020 were gathered. The primary outcome was treatment failure, defined as no improvement in median arcuate ligament syndrome symptoms after MALR or symptom recurrence between MALR and the last clinical follow-up. RESULTS: For 516 patients treated at 24 institutions, open, laparoscopic, and robotic MALR had been performed in 227 (44.0%), 235 (45.5%), and 54 (10.5%) patients, respectively. Perioperative complications (ileus, cardiac, and wound complications; readmissions; unplanned procedures) occurred in 19.2% (open, 30.0%; laparoscopic, 8.9%; robotic, 18.5%; P < .001). The median follow-up was 1.59 years (interquartile range, 0.38-4.35 years). For the 488 patients with follow-up data available, 287 (58.8%) had had full relief, 119 (24.4%) had had partial relief, and 82 (16.8%) had derived no benefit from MALR. The 1- and 3-year freedom from treatment failure for the overall cohort was 63.8% (95% confidence interval [CI], 59.0%-68.3%) and 51.9% (95% CI, 46.1%-57.3%), respectively. The factors associated with an increased hazard of treatment failure on multivariable analysis included robotic MALR (hazard ratio [HR], 1.73; 95% CI, 1.16-2.59; P = .007), a history of gastroparesis (HR, 1.83; 95% CI, 1.09-3.09; P = .023), abdominal cancer (HR, 10.3; 95% CI, 3.06-34.6; P < .001), dysphagia and/or odynophagia (HR, 2.44; 95% CI, 1.27-4.69; P = .008), no relief from a celiac plexus block (HR, 2.18; 95% CI, 1.00-4.72; P = .049), and an increasing number of preoperative pain locations (HR, 1.12 per location; 95% CI, 1.00-1.25; P = .042). The factors associated with a lower hazard included increasing age (HR, 0.99 per increasing year; 95% CI, 0.98-1.0; P = .012) and an increasing number of preoperative diagnostic gastrointestinal studies (HR, 0.84 per study; 95% CI, 0.74-0.96; P = .012) Open and laparoscopic MALR resulted in similar long-term freedom from treatment failure. No radiographic parameters were associated with differences in treatment failure. CONCLUSIONS: No difference was found in long-term failure after open vs laparoscopic MALR; however, open release was associated with higher perioperative morbidity. These results support the use of a preoperative celiac plexus block to aid in patient selection. Operative candidates for MALR should be counseled regarding the factors associated with treatment failure and the relatively high overall rate of treatment failure.

Indications for a "Surgery-First" Approach for the Treatment of Lower Extremity Arterial Disease.

BACKGROUND: In recent years, there has been a tendency toward an "endovascular-first" approach for the treatment for femoropopliteal arterial disease. The purpose of this study is to determine if there are patients that are better served with an initial femoropopliteal bypass (FPB) rather than an endovascular attempt at revascularization. METHODS: A retrospective analysis of all patients undergoing FPB between June 2006 - December 2014 was performed. Our primary endpoint was primary graft patency, defined as patent using ultrasound or angiography without secondary intervention. Patients with <1-year follow-up were excluded. Univariate analysis of factors significant for 5-year patency was performed using χ2 tests for binary variables. A binary logistic regression analysis incorporating all factors identified as significant by univariate analysis was used to identify independent risk factors for 5-year patency. Event-free graft survival was evaluated using Kaplan-Meier models. RESULTS: We identified 241 patients undergoing FPB on 272 limbs. FPB indication was disabling claudication in 95 limbs, chronic limb-threatening ischemia (CLTI) in 148, and popliteal aneurysm in 29. In total, 134 FPB were saphenous vein grafts (SVG), 126 were prosthetic grafts, 8 were arm vein grafts, and 4 were cadaveric/xenografts. There were 97 bypasses with primary patency at 5 or more years of follow-up. Grafts patent at 5 years by Kaplan-Meier analysis were more likely to have been performed for claudication or popliteal aneurysm (63% 5-year patency) as compared with CLTI (38%, P < 0.001). Statistically significant predictors (using log rank test) of patency over time were use of SVG (P = 0.015), surgical indication of claudication or popliteal aneurysm (P < 0.001), Caucasian race (P = 0.019) and no history of COPD (P = 0.026). Multivariable regression analysis confirmed these 4 factors as significant independent predictors of 5-year patency. Of note, there was no statistical correlation between FPB configuration (above or below knee anastomosis, in-situ versus reversed saphenous vein) and 5-year patency. There were 40 FPBs in Caucasian patients without a history of COPD receiving SVG for claudication or popliteal aneurysm that had a 92% estimated 5-year patency by Kaplan-Meier survival analysis. CONCLUSIONS: Long-term primary patency that was substantial enough to consider open surgery as a first intervention was demonstrated in Caucasian patients without COPD, having good quality saphenous vein, and who underwent FPB for claudication or popliteal artery aneurysm.

Long-term outcomes and interventions of postoperative type 1a endoleak following elective endovascular aortic aneurysm repair.

OBJECTIVE: This study evaluated the incidence and long-term outcomes of postoperative type 1a endoleak (PT1a) following endovascular aortic aneurysm repair (EVAR). METHODS: A retrospective review of consecutive aortoiliac EVARs performed at a single institution from June 2006 to June 2012 was conducted. Patients with PT1a were identified by postoperative imaging and compared with those who did not develop a PT1a. Late outcomes were also studied of a subset of patients with PT1a who had persistent intraoperative type 1a endoleak (iT1a) on completion angiogram during EVAR that had resolved on initial follow-up imaging. RESULTS: Three hundred eighty-nine patients underwent EVAR with median follow-up of 87 months (interquartile range, 64-111 months). The incidence of PT1a was 8.2% (n = 32) with a median follow-up of 74 months (interquartile range, 52-138 months). Compared with the total cohort, those who developed PT1a were statistically more likely to be female (32% vs 17%; P = .03) and have a higher all-cause mortality (71% vs 40%; P < .01) and aneurysm-related mortality (15.6% vs 1.7%; P < .01). Median time to presentation was 52 months. Of the 32 patients with PT1a, five (15.6%) presented with aortic rupture, of which three underwent extension cuff placement, one had open graft explant, and one declined intervention. Six patients in total (18.7%) declined intervention; five of these died of nonaneurysmal causes and one remains alive. Of the 26 patients with PT1a who had intervention, 21 (80.7%) showed resolution of PT1a, and five (19.2%) had recurrence. For patients with recurrent PT1a, two had resulting aneurysm-related mortality, two endoleaks resolved after relining with an endograft, and one patient declined intervention but remains alive. Patients with PT1a who had intervention with resolution showed no significant difference in median survival estimates (140.0 months) compared with the remaining EVAR cohort (120.0 months; P = .80). Within the PT1a cohort, 6 (18.7%) had also experienced iT1a with a mean time to presentation of the late PT1a of 45 months. iT1a was associated with a significantly increased likelihood of developing a PT1a (P < .01) and decreased median survival (P < .01), but there was no known aneurysm-related mortality. CONCLUSIONS: Development of PT1a following elective EVAR is associated with increased all-cause and aneurysm-related mortality and presents an average of 52 months postoperatively. This underscores the importance of long-term surveillance. Patients with PT1a who had a successful intervention showed no significant difference in median survival. Those with iT1a had a higher risk for PT1a compared with the EVAR cohort overall and had decreased median survival, without increased aneurysm-related mortality.

Intramural hematoma of the thoracic aorta: A single-institution, 12-year experience.

OBJECTIVE: The natural history and management of intramural hematoma (IMH) has varied significantly worldwide. From the present retrospective analysis of our institutional database, we have reported the long-term results from medical and surgical management of types A and B IMH. METHODS: Computed tomography reports completed at our tertiary care hospital from July 2007 to July 2020 were used to identify patients with IMH with a thickness of ≥7 mm. Those with IMH directly related to trauma, previous aortic surgery, penetrating atheromatous ulcer, dissection flap, or an iatrogenic source and those who had never received any treatment of IMH at presentation were excluded. RESULTS: A total of 54 patients with IMH had met the inclusion and exclusion criteria. Of the 54 patients, 24 had presented with Stanford type A. Of these 24 patients, 10 had initially undergone surgery and 14 had initially received medical treatment. Two patients in the medical group had subsequently undergone surgery. In addition, 30 patients had presented with type B IMH and had initially received medical treatment, with 3 eventually requiring surgical intervention. In-hospital survival was 90% for type A IMH treated surgically, 93% for type A IMH treated medically, and 97% for type B IMH treated medically. At the last follow-up imaging study of the medically treated patients, 36% of those with type A IMH and 31% of those with type B IMH had experienced complete resolution of IMH at 3.7 and 31.5 months respectively, without surgical intervention. The development of an aortic aneurysm at the site of a previous IMH had occurred in 18% (2 of 11) and 12% (3 of 26) of the type A medical and type B medical cohorts. The overall rate of aortic aneurysm formation in the region of IMH or in another segment was 50%. No difference was found in long-term survival between the three cohorts at a mean follow-up of 22.8 months. CONCLUSIONS: A role appears to exist for medical treatment with anti-impulse therapy for appropriately selected patients with type A IMH. These patients must be followed up closely clinically and radiographically for signs of deterioration in the short- and long-term phases of their care. They can achieve long-term survival similar to that of surgically treated type A IMH and medically treated type B IMH patients using this algorithm. However, they might require late surgical intervention, especially for aneurysmal disease.

Predictors of mortality in nonagenarians undergoing abdominal aortic aneurysm repair: Analysis of the National Surgical Quality Improvement Program dataset.

BACKGROUND: The present study used the American College of Surgeons National Surgical Quality Improvement Program dataset to identify the predictors of 30-day mortality for nonagenarians undergoing endovascular aortic aneurysm repair (EVAR) or open surgical repair (OSR). METHODS: Patients aged >90 years who had undergone abdominal aortic aneurysm repair from 2005 to 2017 were identified using procedure codes. Those with operative times <15 minutes were excluded. The demographics, preoperative comorbidities, and postoperative complications of those who had died by 30 days were compared with those of the patients alive at 30 days. RESULTS: A total of 1356 nonagenarians met the criteria: 1229 (90.6%) had undergone EVAR and 127 (9.4%) had undergone OSR. The overall 30-day mortality was 10.4%. The patients who had died within 30 days were significantly more likely to have undergone OSR than EVAR (40.9% vs 7.2%; P < .001). They also had a greater incidence of dependent functional status (22.0% for those who had died vs 8.1% for those alive at 30 days; P < .001), American Society of Anesthesiology (ASA) classification of ≥4 (81.2% vs 18.8%; P < .001), perioperative blood transfusion (59.6% vs 20.3%; P < .001), postoperative pneumonia (12.1% vs 2.9%; P = .001), mechanical ventilation >48 hours (22.7% vs 2.6%; P < .001), and acute renal failure (12.1% vs 0.5%; P < .001). The EVAR group had a 30-day mortality rate of 2.6% in 1008 elective cases and 28.6% in 221 emergent cases. The OSR group had a 30-day mortality rate of 19.1% in 47 elective cases and 53.7% in 80 emergent cases. In the EVAR cohort, the 30-day mortality group had had a significantly greater incidence of dependent functional status (17% for those who had died vs 8% for those alive at 30 days; P = .004), ASA classification of ≥4 (76.4% vs 40.3%; P < .001), perioperative blood transfusion (57% vs 19%; P < .001), emergency surgery (71% vs 14%; P < .001), and longer operative times (150 vs 128 minutes; P = .001). CONCLUSIONS: Nonagenarians had an incrementally increased, but acceptable, risk of 30-day mortality with EVAR in elective and emergent cases compared with that reported for octogenarians and cohorts of patients not selected for age. We found greater mortality for patients with dependent status, a higher ASA classification, emergent repair, and OSR. These preoperative risk factors could help identify the best surgical candidates. Given these results, consideration for EVAR or OSR might be reasonable for highly selected patients, especially for elective patients with a larger abdominal aortic aneurysm diameter for whom the risk of rupture is higher.

Type II endoleak with an enlarging aortic sac after endovascular aneurysm repair predisposes to the development of a type IA endoleak.

OBJECTIVE: The most common endoleak after endovascular aneurysm repair is type II. Although type II endoleaks (TIIEL) are generally considered benign, there are reports that they can lead to aortic rupture. In this study, we reviewed the effect of TIIEL on sac size change to determine if sac expansion owing to a TIIEL could result in the development of a type IA endoleak (TIAEL). METHODS: After internal review board approval, all aortoiliac endovascular aneurysm repairs performed at a single institution between June 2006 and June 2012 were retrospectively reviewed. Patient demographics, comorbidities, aneurysm diameter, graft type, need for reintervention, and complications were collected. Patients with TIIEL diagnosed on follow-up imaging were categorized as those who underwent intervention for their TIIEL and those who did not. Outcomes were tabulated with attention to sac size change, development of TIAEL, rupture, and survival. RESULTS: Six hundred twenty-seven patients underwent aortoiliac stent graft placement at our institution during this time period. Patients with an operative indication other than nonruptured infrarenal abdominal aortic aneurysm and those without preoperative computed tomography angiography or follow-up data available for review were excluded. The total number of patients included was 389 with an average follow-up of 58.8 months (range, 0-194 months). Follow-up imaging diagnosed 124 patients with TIIEL (32%). Patients with TIIEL were significantly older (P < .0001) and more likely to be hypertensive (P < .05) but less likely to be smokers (P = .01). They had a significantly larger sac size increase than patients without TIIEL (9.50 vs -0.78 mm; P < .0001). Those with TIIEL were significantly more likely to develop a TIAEL than patients who did not have TIIEL (14% vs 5%; P = .004), but the rate of rupture was not significantly different (4% vs 2%; P = .33). In those with a TIIEL, the average sac size increase at which TIAEL developed was 13 mm. Patients in the TIIEL group who underwent intervention for their TIIEL survived significantly longer than patients who did not undergo intervention (140 months vs 100 months; P = .004). CONCLUSIONS: Our data suggest that there is an increased incidence of late TIAEL in patients with TIIEL compared with those without a TIIEL. Our study also demonstrates an increased overall survival in TIIEL patients who underwent intervention. Future studies are necessary to better define the association between TIIEL with enlarging sac and the development of TIAEL. However, it is reasonable to conclude that intervention for TIIEL should be undertaken at or before a cumulative sac size increase of 13 mm.

Screening Chest Computed Tomography is Indicated in All Patients with Abdominal Aortic Aneurysm.

BACKGROUND: This study quantifies the prevalence of thoracic aortic aneurysm (TAA) in patients with known abdominal aortic aneurysm (AAA). METHODS: A retrospective review of patients with a diagnosis of AAA from January 2007 to December 2017 within Beaumont Health was undertaken. Radiology reports of abdominal ultrasound, computed tomography (CT), and magnetic resonance imaging were reviewed to identify patients with AAA. Of these, patients with a chest CT scan performed within 180 days before or after abdominal imaging were reviewed for diagnosis of TAA. AAA was defined as aortic diameter ≥30 mm, and TAA was defined as aortic diameter ≥40 mm. RESULTS: The cohort included 218 patients with a chest CT scan performed within 180 days of initial diagnosis of AAA. The mean age at diagnosis of AAA was 74 years; 82 (37.6%) were women. There were no differences between men and women in the prevalence of diabetes mellitus, hypertension, hyperlipidemia, chronic obstructive pulmonary disease, tobacco use, and family history of aortic aneurysm. Forty concomitant AAAs and TAAs were detected, for an overall prevalence of 18.3%, with no significant difference between men and women (15% vs. 24%, P = 0.07). Women were diagnosed with AAA at an older age than men (76 vs. 73 years, P = 0.01) and had lower body mass index (23 vs. 26, P = 0.01), smaller maximum AAA diameter (36.5 vs. 40 mm, P = 0.03), and larger TAA (47 vs. 41 mm, P = 0.01). TAAs were classified by location: 47.5% (19/40), ascending; 32.5% (13/40), descending; and 20% (8/40), ascending and descending. Six patients had thoracoabdominal aortic aneurysms: 2 patients with extent II, 2 with extent III, and 2 with extent V. These patients were included in the overall analysis; excluding them resulted in a rate of concomitant AAA/TAA of 16%. No significant differences were noted in comorbidities or AAA size between the TAA/AAA and AAA only groups. CONCLUSIONS: TAAs appear to occur concomitantly with AAAs with significant frequency. Women appear to have larger TAA diameter than men, despite smaller sized AAA at diagnosis. These data support creating guidelines for obtaining a screening chest CT scan in all patients diagnosed with an AAA.

Outcomes for concomitant common iliac artery aneurysms after endovascular abdominal aortic aneurysm repair.

OBJECTIVE: This study evaluated the morbidity of endovascular abdominal aortic aneurysm repair (EVAR) in patients with concomitant common iliac artery aneurysm (CCIAA). METHODS: This was a retrospective review of all patients who underwent elective EVAR from June 2006 through June 2012 at a single institution. Demographics, comorbidities, preoperative presentation, intraoperative details, and postoperative complications were tabulated. Patients with CCIAA were categorized into three groups according to the distal extent of their iliac limb: iliac limb extension into the external iliac artery with internal iliac artery coil embolization (EE); flared iliac limb ≥20 mm in diameter to the iliac bifurcation (FL); and iliac limb ≤20 mm ending proximal to the CCIAA (no-FL). RESULTS: During this period, 627 consecutive patients underwent elective EVAR and preoperative computed tomographic angiograms were available for 523 patients to evaluate the presence of CCIAA. Of these, 211 patients (40.2%) had a CCIAA in at least one common iliac artery, with a total of 307 aneurysmal arteries. Of these 307 aneurysmal arteries, 62 (20.2%) were treated with EE, 132 (43.0%) were treated with FL, and 113 (36.8%) had a sufficient landing zone in the proximal common iliac artery to use an iliac limb ≤20 mm in diameter (no-FL). The overall reintervention rate was 12.4% of patients, with a higher reintervention rate between patients with CCIAA compared with those without (15.2% vs 10.9%; P = .039). There were no significant differences in reintervention rates between the EE, FL, and no-FL techniques (4.5% vs 4.8% vs 6.2%; P = .802) over a mean 59.8 months follow-up. The FL and EE techniques had a lower risk of distal endoleak than the no-FL technique, but the difference was not statistically significant (3.2% vs 2.3% vs 5.3% compared with 4.23% in the entire cohort). CONCLUSIONS: Patients with CCIAA had a higher reintervention rate after EVAR for abdominal aortic aneurysm compared with non-CCIAA patients. Of the techniques studied (EE, FL, and no-FL), there was no significant difference in reintervention rates between the three. All three techniques remain viable options for the endovascular repair of CCIAA.

Predictors of readmission in nonagenarians: analysis of the American College of Surgeons National Surgical Quality Improvement Project dataset.

BACKGROUND: Increased longevity has led to more nonagenarians undergoing elective surgery. Development of predictive models for hospital readmission may identify patients who benefit from preoperative optimization and postoperative transition of care intervention. Our goal was to identify significant predictors of 30-d readmission in nonagenarians undergoing elective surgery. METHODS: Nonagenarians undergoing elective surgery from January 2011 to December 2012 were identified using the American College of Surgeons National Surgical Quality Improvement Project participant use data files. This population was randomly divided into a 70% derivation cohort for model development and 30% validation cohort. Using multivariate step-down regression, predictive models were developed for 30-d readmission. RESULTS: Of 7092 nonagenarians undergoing elective surgery, 798 (11.3%) were readmitted within 30 d. Factors significant in univariate analysis were used to develop predictive models for 30-d readmissions. Diabetes (odds ratio [OR]: 1.51, 95% confidence interval [CI]: 1.24-1.84), dialysis dependence (OR: 2.97, CI: 1.77-4.99), functional status (OR: 1.52, CI: 1.29-1.79), American Society of Anesthesiologists class II or higher (American Society of Anesthesiologist physical status classification system; OR: 1.80, CI: 1.42-2.28), operative time (OR: 1.05, CI: 1.02-1.08), myocardial infarction (OR: 5.17, CI: 3.38-7.90), organ space surgical site infection (OR: 8.63, CI: 4.04-18.4), wound disruption (OR: 14.3, CI: 4.80-42.9), pneumonia (OR: 8.59, CI: 6.17-12.0), urinary tract infection (OR: 3.88, CI: 3.02-4.99), stroke (OR: 6.37, CI: 3.47-11.7), deep venous thrombosis (OR: 5.96, CI: 3.70-9.60), pulmonary embolism (OR: 20.3, CI: 9.7-42.5), and sepsis (OR: 13.1, CI: 8.57-20.1), septic shock (OR: 43.8, CI: 18.2-105.0), were included in the final model. This model had a c-statistic of 0.73, indicating a fair association of predicted probabilities with observed outcomes. However, when applied to the validation cohort, the c-statistic dropped to 0.69, and six variables lost significance. CONCLUSIONS: A reliable predictive model for readmission in nonagenarians undergoing elective surgery remains elusive. Investigation into other determinants of surgical outcomes, including social factors and access to skilled home care, might improve model predictability, identify areas for intervention to prevent readmission, and improve quality of care.

Rupture of Abdominal Aortic Aneurysm in Patients with and without Antecedent Endovascular Repair.

BACKGROUND: Reported results of ruptured abdominal aortic aneurysm (rAAA) in patients with antecedent endovascular aneurysm repair (EVAR) to those presenting with de novo rupture show a similar or slightly improved outcome. The aim of this study was to compare differences in the presentation and outcomes of rAAA with and without prior EVAR. METHODS: A retrospective review of 121 patients with rAAA, ruptured identified 2 groups. Group A included 17 patients (rAAA n = 17) with antecedent EVAR and group B consisted of 104 patients (rAAA n = 104) with de novo ruptures, from January 2001 to March 2015 in 3 teaching hospitals. Patient characteristics and perioperative variables were compared; Fisher's exact test was used for categorical variables. For continuous variables, Student's t-test and Mann-Whitney U test were used. RESULTS: Both groups were similar in age, gender, the incidence of hypertension, coronary artery disease, diabetes mellitus, chronic obstructive pulmonary disease, and nicotine abuse. Mean time of presentation from EVAR to rupture in group A was 42 ± 22 months. Mean preoperative transverse or anteroposterior diameter of AAA was 6.6 cm in group A and 7.1 cm in group B. Three patients of 17 (17.6%) in group A were hemodynamically unstable as compared to 47 of 104 patients (45.1%) in group B (P = 0.03). Mean red blood cells, fresh frozen plasma, and platelet transfusion were similar in both groups. Thirty-day mortality was 8 of 17 (44.7%) in group A and 44 of 104 (42.3%) in group B (P = 1.0). Postoperative complications were also similar in both groups except the incidence of postoperative respiratory failure was higher in group B (38%) as compared with 11.1% in group A (P = 0.001). CONCLUSIONS: Patients presenting with rAAA with antecedent EVAR are hemodynamically more stable as compared with patients with de novo rupture of AAA. Postoperative respiratory failure is more common in patients with de novo rupture. rAAA carry high mortality with and without prior EVAR.

Process for Managing and Optimizing Radiology Work Flow in the Electronic Heath Record Environment.

Electronic health record (EHR) implementation has dramatically impacted all facets of radiology workflow. Many departments find themselves unprepared for the multiple issues that surface following EHR deployment and the ongoing need for workflow optimization. This paper reviews the structure and processes utilized by the team, developed at the University of Colorado Hospital to evaluate, prioritize, and implement requests for workflow repairs and improvements within the EHR. The evolution of this team as the academic hospital formed a health system with two community hospital sites is also described. This structure may serve as a useful template for others considering EHR deployment or struggling to manage radiology workflow within an existing EHR environment.

Incidence of venous thromboembolism in patients with sickle cell disease undergoing noncardiovascular surgery.

OBJECTIVE: Patients with sickle cell disease (SCD) will have a baseline hypercoagulable state and an increased risk of venous thromboembolism (VTE). Few data are available regarding the efficacy of standard prophylaxis in preventing VTE after noncardiovascular surgery for patients with SCD. Our objective was to investigate the incidence of VTE in patients with SCD who had undergone noncardiovascular surgery. METHODS: We performed a retrospective medical record review of 352 patients with SCD who had undergone noncardiovascular surgery from August 2009 to August 2019 at Beaumont Hospitals. An equal number of control patients without SCD were propensity matched for age, sex, race, body mass index, and specific surgery. The data collected included demographics, comorbidities, VTE prophylaxis used, occurrence of deep vein thrombosis (DVT) and pulmonary embolism (PE), hospital length of stay, and 30-day mortality. RESULTS: We found no differences in age, race, sex, ethnicity, operative time, or hospital length of stay between the SCD and propensity-matched control patients. DVT prophylaxis was used more frequently for the SCD patients than for the controls (96.0% vs 88.6%; P < .001). Four SCD patients (1.1%) had developed DVT vs five control patients (1.4%; P > .999). One patient in each group had developed PE (0.3%; P > .999). No difference was found in 30-day mortality between the SCD group and the control group (1 [0.3%] vs 3 [0.9%]; P = .312). Of those with a diagnosis of VTE ≤30 days postoperatively, no differences were present in age, sex, race, BMI, or procedure type. DVT had been diagnosed significantly later in the SCD patients than in the controls (median, postoperative day 12 vs 5; P = .014). None of the five SCD patients with VTE was a smoker compared with four of the six non-SCD patients with VTE, who were current or former tobacco users (P = .061). All the patients who had developed VTE had received DVT prophylaxis at surgery. CONCLUSIONS: We found no differences in the perioperative rates of DVT, PE, or mortality between the SCD patients and matched control patients after noncardiovascular surgery. Vigilant attention to routine VTE prophylaxis seemed to effectively reduce the VTE risk for these hypercoagulable patients. SCD patients might need VTE prophylaxis for a longer period postoperatively compared with those without SCD.

Evaluation of potential responses to invasive non-native species with structured decision making.

In managing invasions and colonizations of non-native species, eradication or control efforts must proceed quickly. There are 2 challenges in taking such quick action. First, managers frequently have to choose among complex and often competing environmental, social, and economic objectives. Second, the effects are highly uncertain. We applied participatory structured decision making (SDM) to develop a response plan for the recent invasion of non-native myrtle rust (Uredo rangelii) in Australia. Structured decision making breaks a complex decision process into 5 steps: identify problems (i.e., decisions to be made), formulate objectives, develop management alternatives, estimate consequences of implementing those alternatives, and select preferred alternatives by evaluating trade-offs among alternatives. To determine the preferred mid- to long-term alternatives to managing the rust, we conducted 2 participatory workshops and 18 interviews with individuals to elicit stakeholders' key concerns and convert them into 5 objectives (minimize management cost, minimize economic cost to industry, minimize effects on natural ecosystems and landscape amenities, and minimize environmental effects associated with use of fungicide) and to identify the 5 management alternatives (full eradication, partial eradication, slow spread, live with it [i.e., major effort invested in mitigation of effects], and do nothing). We also developed decision trees to graphically represent the essence of the decision by displaying the relations between uncertainties and decision points. In the short term or before local expansion of myrtle rust, the do-nothing alternative was not preferred, but an eradication alternative was only recommended if the probability of eradication exceeded about 40%. After the expansion of myrtle rust, the slow-the-spread alternative was preferred regardless of which of the short-term management alternatives was selected at an earlier stage. The participatory SDM approach effectively resulted in informed and transparent response plans that incorporated multiple objectives in decision-making processes under high uncertainty.

Deliberative disjunction: expert and public understanding of outcome uncertainty.

Many environmental and risk management decisions are made jointly by technical experts and members of the public. Frequently, their task is to select from among management alternatives whose outcomes are subject to varying degrees of uncertainty. Although it is recognized that how this uncertainty is interpreted can significantly affect decision-making processes and choices, little research has examined similarities and differences between expert and public understandings of uncertainty. We present results from a web-based survey that directly compares expert and lay interpretations and understandings of different expressions of uncertainty in the context of evaluating the consequences of proposed environmental management actions. Participants responded to two hypothetical but realistic scenarios involving trade-offs between environmental and other objectives and were asked a series of questions about their comprehension of the uncertainty information, their preferred choice among the alternatives, and the associated difficulty and amount of effort. Results demonstrate that experts and laypersons tend to use presentations of numerical ranges and evaluative labels differently; interestingly, the observed differences between the two groups were not explained by differences in numeracy or concerns for the predicted environmental losses. These findings question many of the usual presumptions about how uncertainty should be presented as part of deliberative risk- and environmental-management processes.

When experts disagree (and better science won't help much): using structured deliberations to support endangered species recovery planning.

Progress on recovery plans to conserve endangered species is often blocked due to the lack of an effective framework that technical experts and other knowledgeable stakeholders can use to examine areas of agreement or disagreement about the anticipated effects of management actions. Multi-party, multi-interest resource management deliberations, although increasingly common, are difficult in the context of recovery planning due to the range of potentially affected environmental, economic, and social concerns. These deliberations are further complicated by frequent disagreements among technical experts about how to identify and address various sources of biological uncertainty. We describe the development of a decision-aiding framework as part of an inter-agency plan to assist recovery of endangered Gulf of Maine Atlantic salmon (Salmo salar), using a structured decision making approach that encouraged constructive deliberations based on rigorous analysis. Results are summarized in terms of developing an explicit set of management objectives, clarifying and prioritizing hypotheses concerning barriers to recovery, comparing alternative management initiatives in light of biological uncertainty, and incorporating resource constraints to generate preferred sets of actions. Overall, the use of a structured approach to making recovery decisions improved inter-agency cooperation and facilitated dialogue, understanding, and agreement among participating experts. It also helped to create a defensible basis for further internal discussions as well as for communicating with external stakeholders, including resource users and political decision makers.

Contemporary management and outcomes of peripheral venous aneurysms: A multi-institutional study.

OBJECTIVE: Extremity venous aneurysms result in the risk of pulmonary embolism (PE) and chronic venous insufficiency. At present, owing to the rarity of these aneurysms, no consensus for their treatment has been established. The purpose of the present study was to review the presentation, natural history, and contemporary management of extremity venous aneurysms. METHODS: We performed a retrospective, multi-institutional review of all patients with extremity venous aneurysms treated from 2008 to 2018. A venous aneurysm was defined as saccular or fusiform with an aneurysm/vein ratio of >1.5. RESULTS: A total of 66 extremity aneurysms from 11 institutions were analyzed, 40 of which were in a popliteal location, 14 iliofemoral, and 12 in an upper extremity or a jugular location. The median follow-up was 27 months (range, 0-120 months). Of the 40 popliteal venous aneurysms, 8 (20%) had presented with deep vein thrombosis (DVT) or PE, 13 (33%) had presented with pain, and 19 had been discovered incidentally. The mean size of the popliteal venous aneurysms presenting with DVT or PE was larger than that of those presenting without thromboembolism (3.8 cm vs 2.5 cm; P = .003). Saccular aneurysm morphology in the lower extremity was associated with thromboembolism (30% vs 9%; P = .046) and fusiform aneurysm morphology with a thrombus burden >25% (45% vs 3%). Patients presenting with thromboembolism were more likely to have had a thrombus burden >25% in their lower extremity venous aneurysm compared with those who had presented without thromboembolism (70% vs 9%). Approximately half of all the patients underwent immediate intervention, and half were managed with observation or antithrombotic regimen. In the non-operative cohort, three patients subsequently developed a DVT. Eight patients in the medically managed cohort went on to require surgical intervention. Of the 12 upper extremity venous aneurysms, none had presented with DVT or PE, and only 2 (17%) had presented with pain. Of the 66 patients in the entire cohort, 41 underwent surgical intervention. The most common indication was the absolute aneurysm size. Nine patients had undergone surgery because of a DVT or PE, and 11 for pain or extremity swelling. The most common surgery was aneurysmorrhaphy in 21 patients (53%), followed by excision and ligation in 14 patients (35%). Five patients (12%) had undergone interposition bypass grafting. A postoperative hematoma requiring reintervention was the most common complication, occurring in three popliteal vein repairs and one iliofemoral vein repair. None of the patients, treated either surgically or medically, had reported post-thrombotic complications during the follow-up period. CONCLUSIONS: Large lower extremity venous aneurysms and saccular aneurysms with thrombus >25% of the lumen are more likely to present with thromboembolic complications. Surgical intervention for lower extremity venous aneurysms is indicated to reduce the risk of venous thromboembolism (VTE) and the need for continued anticoagulation. Popliteal aneurysms >2.5 cm and all iliofemoral aneurysms should be considered for repair. Upper extremity aneurysms do not have a significant risk of VTE and warrant treatment primarily for symptoms other than VTE.

Open vs. endovascular repair of isolated iliac artery aneurysms: A 12-year experience.

OBJECTIVE: To examine contemporary operative techniques and outcomes for repair of isolated iliac artery aneurysms. METHODS: We retrospectively reviewed the charts of all patients who underwent repair of an isolated iliac artery aneurysm from February 1995 to June 2007. Mycotic aneurysms and patients with concurrent infrarenal abdominal aortic aneurysms greater than 3.5 cm in diameter were excluded from analysis. Patients with prior abdominal aortic aneurysm repair were not excluded. RESULTS: Fifty-six patients (96% male; mean age, 72 +/- 10 years) had either open (n = 24) or endovascular (n = 32) repair with median follow-up of 36 months. Seven patients were treated for rupture, six with open repair, and one with an endograft. Average aneurysm size for patients in the open and endovascular repair cohorts was 4.5 +/- 2.4 cm and 4.0 +/- 1.1 cm, respectively (P = .35). One episode of endograft limb thrombosis at five months was treated with catheter-directed thrombolytic therapy and stent placement. Thirty-day mortality for patients undergoing elective and emergent open repair was 1/18 (6%) and 1/6 (17%), respectively. There was no 30-day mortality for the endovascular group. Median length of stay was 10.5 days in the open group and one day in the endovascular elective group (P < .01). There was no mid-term aneurysm-related mortality in either group. Primary patency rates were similar between the open and endovascular groups at five years (100% vs. 96%, P = .07). Aneurysm sac diameter decreased in 67% (21/28) of patients that underwent endovascular repair. One patient with a Type III endoleak required relining of the endograft with a second endograft at 72 months. CONCLUSION: These data demonstrate that in appropriately selected patients, endovascular repair of isolated iliac artery aneurysms is a safe, effective alternative to open repair with mid-term follow-up. Endovascular repair is associated with a significantly reduced hospital length of stay and may be associated with decreased need for transfusion and mortality when compared with open repair.

Clostridium septicum aortitis: Report of two cases and review of the literature.

Clostridium septicum aortitis is a rare infection that has a strong association with occult colonic malignancy. To our knowledge, we report the 25th and 26th cases of C septicum aortitis in the English literature and make recommendations for its management. The first patient was a 75-year-old man who presented with abdominal pain. Computed tomography showed the presence of periaortic gas. He underwent aortic débridement and extra-anatomic bypass after blood cultures revealed C septicum. Four months after the initial presentation, he was readmitted with lethargy, found to have recurrent periaortic gas, and died. The second patient was a 76-year-old woman who presented with a 5-cm abdominal aortic aneurysm with surrounding retroperitoneal gas. She underwent emergency aortic ligation and retroperitoneal débridement. Her blood and intraoperative tissue cultures also grew C septicum. She had a prolonged postoperative course and ultimately died on hospital day 94. Both patients were found to have concurrent colon adenocarcinomas. C septicum aortitis is a lethal disease that necessitates prompt surgical intervention and appropriate antibiotic therapy. The strong association of C septicum with occult malignancy should prompt the astute clinician to undertake an exhaustive search for a neoplastic process.

Using structured decision making to help implement a precautionary approach to endangered species management.

Endangered species protection is a significant risk management concern throughout North America. An extensive conceptual literature emphasizes the role to be played by precautionary approaches. Risk managers, typically working in concert with concerned stakeholders, frequently cite the concept as key to their efforts to prevent extinctions. Little has been done, however, to evaluate the multidimensional impacts of precautionary frameworks or to assist in the examination of competing precautionary risk management options as part of an applied risk management decision framework. In this article we describe how decision-aiding techniques can assist in the creation and analysis of alternative precautionary strategies, using the example of a multistakeholder committee charged with protection of endangered Cultus Lake salmon on the Canadian west coast. Although managers were required to adopt a precautionary approach, little attention had been given to how quantitative analyses could be used to help define the concept or to how a precautionary approach might be implemented in the face of difficult economic, social, and biological tradeoffs. We briefly review key steps in a structured decision-making (SDM) process and discuss how this approach was implemented to help bound the management problem, define objectives and performance measures, develop management alternatives, and evaluate their consequences. We highlight the role of strategy tables, employed to help participants identify, alternative management options. We close by noting areas of agreement and disagreement among participants and discuss the implications of decision-focused processes for other precautionary resource management efforts.

Diagnosis of total internal carotid occlusions with duplex ultrasound and ultrasound contrast.

It remains a significant technical challenge for duplex ultrasound to accurately differentiate between total and near total internal carotid artery (ICA) occlusions. We have evaluated the efficacy of an ultrasound contrast agent combined with improved imaging techniques in patients with suspected carotid artery occlusions. Patients identified by conventional duplex ultrasound between January and August 2003 as having a possible ICA occlusion were eligible for study. A 1 mL bolus of ultrasound contrast agent was injected into a 50 mL bag of normal saline and given intravenously at a rate of approximately 4-5 mL/minute. Ultrasound imaging and spectral Doppler analysis were done using tissue harmonic imaging for optimum contrast agent to soft tissue discrimination, or with the direct B-mode imaging of blood flow to maximize the brightness of the circulating contrast agent. Ten patients were identified, 6 men and four women with a mean age of 68.3 years. Nine suspected total ICA occlusions were unilateral and 1 was bilateral. Imaging with contrast agent confirmed occlusion of the ICA in 7 of 10 patients; 3 patients had near-total occlusion with flow detected in the distal ICA by spectral and color Doppler. All 3 of these near-total occlusions were ultimately confirmed by either conventional or magnetic resonance carotid angiography. The contrast agent was most beneficial in improving the detection of minimal flow beyond a severe stenosis and in evaluating flow dynamics in the presence of severely calcified plaque. We conclude that the use of an ultrasound contrast agent with newer duplex ultrasound imaging techniques can reliably distinguish total from near-total internal carotid artery occlusions. Future prospective studies should be able to define the efficacy of ultrasound contrast agents in improving the overall diagnostic accuracy of duplex ultrasound in technically difficult cases and in patients with complex peripheral vascular disease.