Cannabis use disorder and perioperative outcomes in vascular surgery.

BACKGROUND: Heavy cannabis use is known to have an adverse impact on cardiovascular and cerebrovascular outcomes in the general population and in patients presenting for surgery. However, there have been no studies that have focused on patients undergoing vascular surgical procedures. The objective of this study was to determine the perioperative risk of cannabis use disorder (CUD), primarily cardiovascular risk, in perioperative vascular surgery patients. METHODS: Using the National Inpatient Sample from 2006 to 2015, we conducted a retrospective cohort study involving those undergoing one of six elective and emergent vascular surgical procedures (carotid endarterectomy [CEA], infrainguinal bypasses, open abdominal aortic aneurysm repair, aortobifemoral bypass, endovascular aortic aneurysm repair, or peripheral arterial endovascular procedures). Patients with CUD identified by the International Classification of Diseases, 9th edition, were matched with patients without CUD in a 1:1 ratio using propensity scores. The primary outcome was perioperative myocardial infarction (MI). Secondary outcomes include stroke, sepsis, deep vein thrombosis, pulmonary embolus, acute kidney injury requiring dialysis, respiratory failure, in-hospital mortality, total cost, and length of stay. RESULTS: We identified a total cohort of 510,007 patients. Over the study period, the recorded prevalence of CUD increased from 1.3/1000 to 10.3/1000 admissions (P < .001). After propensity score matching the cohort consisted of 4684 patients. Those with CUD had a higher incidence of perioperative MI (3.3% vs 2.1%; odds ratio [OR], 1.56; 95% confidence interval [CI], 1.09-2.24; P = .016) and perioperative stroke (5.5% vs 3.5%; OR, 1.59; 95% CI, 1.20-2.12; P = .0013) than patients without CUD. In a sensitivity analysis, where the risk was evaluated separately by type of procedure, the higher incidence of perioperative stroke was primarily seen among those undergoing CEA. Patients with CUD had a lower incidence of sepsis (3.3% vs 5.1%; OR, 0.64; 95% CI, 0.47-0.85; P = .0024). We obtained similar results in a sensitivity analysis that included all patients in the complete unmatched cohort and adjusted for confounding using logistic regression models accounting for the survey design, although the findings of sepsis and stroke failed to reach statistical significance after correcting for multiple testing (MI P = .001; stroke P = .031; sepsis P = .009). CONCLUSIONS: CUD was associated with a significantly higher incidence of perioperative MI in vascular surgery patients. Those with CUD had a greater incidence of diagnosis of acute perioperative stroke when undergoing CEA. Owing to limitations in administrative data, it is unclear if this represents a true effect or selection bias. These findings warrant further investigation in a prospective cohort.

A Systematic Review of Economic Evaluations in Vascular Surgery.

BACKGROUND: With increasing healthcare costs and the emergence of new technologies in vascular surgery, economic evaluations play a critical role in informing decision-making that optimizes patient outcomes while minimizing per capita costs. The objective of this systematic review is to describe all English published economic evaluations in vascular surgery and to identify any significant gaps in the literature. METHODS: We conducted a comprehensive English literature review of EMBASE, MEDLINE, The Cochrane Library, Ovid Health Star, and Business Source Complete from inception until December 1, 2018. Two independent reviewers screened articles for eligibility using predetermined inclusion criteria and subsequently extracted data. Articles were included if they compared 2 or more vascular surgery interventions using either a partial economic evaluation (cost analysis) or full economic evaluation (cost-utility, cost-benefit, and/or cost-effectiveness analysis). Data extracted included publishing journal, date of publication, country of origin of authors, type of economic evaluation, and domain of vascular surgery. RESULTS: A total of 234 papers were included in the analysis. The majority of the papers included only a cost analysis (183, 78%), and there were only 51 papers that conducted a full economic analysis (22%). The 51 papers conducted a total of 69 economic analyses. This consisted of 32 cost-effectiveness analyses, 29 cost-utility analyses, and 8 cost-benefit analyses. The most common domains studied were aneurysmal disease (89, 38%) and peripheral vascular disease (50, 21%). Economic evaluations were commonly published in the Journal of Vascular Surgery (83, 35%) and Annals of Vascular Surgery (32, 14%), with most study authors located in the United States (127, 54%). There was a trend of economic evaluations being published more frequently in recent years. CONCLUSIONS: The majority of vascular surgery economic evaluations used only a cost analysis, rather than a full economic evaluation, which may not be ideal in pursuing interventions that simultaneously optimize cost and patient outcomes. The literature is lacking in full economic evaluations-a trend persistent in other surgical specialties-and there is a need for full economic evaluations to be conducted in the field of vascular surgery.

Factors relating to the publication rate of abstracts presented from 2012 to 2015 at the Society for Vascular Surgery Annual Meeting.

OBJECTIVE: The Society for Vascular Surgery's Annual Meeting acts as a means of disseminating research findings among vascular surgeons through the presentation of research abstracts. Following presentation at the meeting, research is often compiled into a full-text manuscript and submitted to a peer-reviewed journal. However, not all abstracts accepted to the Vascular Annual Meeting (VAM) eventually have a corresponding full-text publication. The objectives of this study were to establish the publication rate of abstracts presented between 2012 and 2015 to the VAM and to identify factors correlating with publication status. METHODS: Abstracts presented at the VAM were available through the Journal of Vascular Surgery. Data extracted from eligible abstracts included level of evidence according to the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence scheme, type of study (prognostic, therapeutic/harm, diagnostic), sample size, and status of outcome (positive, negative, or descriptive findings). Publication status of the abstracts was determined through a comprehensive literature review of PubMed (MEDLINE), Ovid (MEDLINE), and Embase. A multivariable logistic regression was conducted to determine factors correlating with publication status. RESULTS: The publication rate during the study period was 43.0% with a median time to publication of 9 months, with 412 of the 958 abstracts having a corresponding full-text publication in 48 journals with weighted mean impact factor of 3.40. Eleven journals collectively published 372 (90.3%) of the articles, with the Journal of Vascular Surgery publishing 280 (68.0%) of the manuscripts. Our logistic regression model demonstrated that factors positively affecting publication status were a positive status of outcome (odds ratio, 2.59; 95% confidence interval, 1.56-4.28) and a logarithmic increase in the sample size of the study (odds ratio, 1.35; 95% confidence interval, 1.13-1.60). In addition, studies with a corresponding full-text publication had a greater median sample size (250) compared with those without one (143; P < .001). CONCLUSIONS: From 2012 to 2015, 43.0% of VAM abstracts had a corresponding full-text publication, with greater sample size and a positive status of outcome positively correlating with likelihood of publication. Studies with negative findings made up a small proportion of conference abstracts (9.6%) and were the least likely to be published. Given the relatively small size of the specialty of vascular surgery, it may be particularly important to be mindful of publication bias. It may be worthwhile to give additional consideration to acceptance of abstracts or publication of studies with negative results that meaningfully contribute to the literature.

Use of the National Surgical Quality Initiative Program in Vascular Surgery Research.

BACKGROUND: The National Surgical Quality Improvement Program (NSQIP) is a prospectively collected database that collects 30-day patient outcome data, and analyzes these data for risk adjusted comparisons. The purpose of this review is to determine how this database is used in vascular surgery literature. METHODS: With the assistance of a librarian, a comprehensive search string was developed to survey the NSQIP vascular surgery literature in PubMed, EMBASE, MEDLINE, and CINAHL. Two reviewers independently reviewed the articles. To be included in the study articles had to relate to one of the domains of vascular surgery and utilize the NSQIP database. RESULTS: One hundred fifty-six articles were included in this review. All studies were retrospective and the most common study type was retrospective cohort studies (65.4%). Although 2016 was the year with the most published articles (22.4%), 2014 and 2015 stand out as going against the upward trend of number of published articles in respect to year. The most prominent aims of the studies were to find preoperative predictors of adverse outcomes (50.6%). There were a minority of studies investigating quality improvement following implementation of the NSQIP (5.1%) or validation and examination of risk predicting tools (3.8%). Of the surgical domains investigated by studies, the use of aneurysm repair data was most common (33.3%) followed by lower extremity revascularization or amputation (28.2%). Within these surgical domains, majority of studies were interested specifically in open cases (51.9%). Although there was some range in outcomes investigated, mortality and morbidity were one of the primary outcomes in majority of the studies (mortality 65.0%, morbidity 57.3%). CONCLUSIONS: Since its inception, the NSQIP has grown in both hospital implementation and vascular surgery literature. Although a variety of literature exists that uses said NSQIP data to predict and compare adverse events, not much literature exists surrounding the translation of implementing these findings into the hospital setting. Additionally, despite the size of the database, many existing studies investigate similar aims and outcomes to each other.

Myocardial Injury After Noncardiac Surgery (MINS) in Vascular Surgical Patients: A Prospective Observational Cohort Study.

OBJECTIVE: To determine the prognostic relevance, clinical characteristics, and 30-day outcomes associated with myocardial injury after noncardiac surgery (MINS) in vascular surgical patients. BACKGROUND: MINS has been independently associated with 30-day mortality after noncardiac surgery. The characteristics and prognostic importance of MINS in vascular surgery patients are poorly described. METHODS: This was an international prospective cohort study of 15,102 noncardiac surgery patients 45 years or older, of whom 502 patients underwent vascular surgery. All patients had fourth-generation plasma troponin T (TnT) concentrations measured during the first 3 postoperative days. MINS was defined as a TnT of 0.03 ng/mL of higher secondary to ischemia. The objectives of the present study were to determine (i) if MINS is prognostically important in vascular surgical patients, (ii) the clinical characteristics of vascular surgery patients with and without MINS, (iii) the 30-day outcomes for vascular surgery patients with and without MINS, and (iv) the proportion of MINS that probably would have gone undetected without routine troponin monitoring. RESULTS: The incidence of MINS in the vascular surgery patients was 19.1% (95% confidence interval (CI), 15.7%-22.6%). 30-day all-cause mortality in the vascular cohort was 12.5% (95% CI 7.3%-20.6%) in patients with MINS compared with 1.5% (95% CI 0.7%-3.2%) in patients without MINS (P < 0.001). MINS was independently associated with 30-day mortality in vascular patients (odds ratio, 9.48; 95% CI, 3.46-25.96). The 30-day mortality was similar in MINS patients with (15.0%; 95% CI, 7.1-29.1) and without an ischemic feature (12.2%; 95% CI, 5.3-25.5, P = 0.76). The proportion of vascular surgery patients who suffered MINS without overt evidence of myocardial ischemia was 74.1% (95% CI, 63.6-82.4). CONCLUSIONS: Approximately 1 in 5 patients experienced MINS after vascular surgery. MINS was independently associated with 30-day mortality. The majority of patients with MINS were asymptomatic and would have gone undetected without routine postoperative troponin measurement.

Level of clinical evidence presented at the Society for Vascular Surgery Annual Meeting during a 5-year period (2012-2016).

OBJECTIVE: During the past decades, there has been an increasing emphasis on the use of high-quality evidence to inform clinical decision-making. The purpose of our study was to assess trends in the level of evidence (LOE) of abstracts presented at the Vascular Annual Meeting from 2012 to 2016. METHODS: All Vascular Annual Meeting abstracts for 2012 to 2016 were obtained through the Journal of Vascular Surgery. Two reviewers independently screened abstracts for eligibility. Research with a nonclinical focus was excluded from the study. Data extracted from eligible abstracts included study type (therapeutic, prognostic, diagnostic), study size, country of academic institution of primary author, presentation type, and whether the sample was recruited or from a database. Abstracts were assigned an LOE using the 2011 Oxford Centre for Evidence-Based Medicine classification scheme based on study design (eg, case series, randomized controlled trial). A χ2 test and analysis of variance test were conducted to assess nonrandom changes in LOE during the study period. RESULTS: Of the 1403 abstracts screened, 1147 were included. Inter-rater agreement was high (κ value for abstract screening was 0.93; κ value for data extraction was 0.89). Therapeutic studies were the most common study type (58%), followed by prognostic studies (37%), then diagnostic studies (5%). The majority of abstracts (75.0%) were submitted from North American institutions. Overall, 0.35% of the presentations were level I evidence, 3.1% level II, 52.8% level III, 38.0% level IV, and 5.7% level V. The average LOE per year fluctuated between 3.54 and 3.32, with a mean LOE of 3.45. The proportion of high-quality evidence (level I and level II) increased in the years 2015 and 2016, representing 78% of all level I and level II abstracts presented in the 5-year period. A χ2 test between LOE and year yielded a P value of .0084, indicating significant nonrandom change in LOE between 2012 and 2016. The majority of high LOE research was presented in poster sessions (37.5%), plenary sessions (27.5%), and international forum sessions/talks (25%) at the meeting. CONCLUSIONS: Overall, average LOE remained relatively consistent between 2012 and 2016, with most abstracts classified as level III or level IV. There was a gradual, albeit minor, increase in the proportion of level I and level II evidence in 2015 and 2016, potentially indicating the increasing commitment to producing and disseminating high-level research in vascular surgery. Furthermore, a lack of a classification tool specific to vascular surgery research occasionally presented a challenge in assigning LOE, perhaps indicating a need for such a tool in this specialty.

Evaluating the Effectiveness of Internal Iliac Artery Branched Endovascular Stent Grafts.

BACKGROUND: The aim of this study is to describe our institutional experience using iliac branch grafts (IBGs) in aortoiliac aneurysm repair. METHODS: From October 2009 to April 2016, 41 consecutive patients (all men), mean age 71.7 years (range 55-87), underwent IBG implantation. Abdominal aortic aneurysm with common iliac artery involvement (n = 21) or bilateral common iliac artery aneurysms (n = 20) were indications. Computed tomography was used to evaluate patency and postoperative endoleaks within 1 month of implantation and after 1 year. RESULTS: A total of 42 IBGs were deployed in 41 patients successfully. One hundred percent of grafts implanted were patent at 1 month and at annual follow-up. There was 1 mortality at 30 days, due to acute renal failure. Sixteen type II and 1 type Ib endoleaks were found, for which 3 reinterventions were performed and the remainder treated conservatively. Five patients had complications which required reintervention. CONCLUSIONS: IBG placement has excellent short-term outcomes and potential to limit buttock claudication in the treatment of abdominal aortic aneurysms involving the iliac arteries.

Risk Factors for Hospital Readmission Following Noncardiac Surgery: International Cohort Study.

Objective: To determine timing and risk factors associated with readmission within 30 days of discharge following noncardiac surgery. Background: Hospital readmission after noncardiac surgery is costly. Data on the drivers of readmission have largely been derived from single-center studies focused on a single surgical procedure with uncertainty regarding generalizability. Methods: We undertook an international (28 centers, 14 countries) prospective cohort study of a representative sample of adults ≥45 years of age who underwent noncardiac surgery. Risk factors for readmission were assessed using Cox regression (ClinicalTrials.gov, NCT00512109). Results: Of 36,657 eligible participants, 2744 (7.5%; 95% confidence interval [CI], 7.2-7.8) were readmitted within 30 days of discharge. Rates of readmission were highest in the first 7 days after discharge and declined over the follow-up period. Multivariable analyses demonstrated that 9 baseline characteristics (eg, cancer treatment in past 6 months; adjusted hazard ratio [HR], 1.44; 95% CI, 1.30-1.59), 5 baseline laboratory and physical measures (eg, estimated glomerular filtration rate or on dialysis; HR, 1.47; 95% CI, 1.24-1.75), 7 surgery types (eg, general surgery; HR, 1.86; 95% CI, 1.61-2.16), 5 index hospitalization events (eg, stroke; HR, 2.21; 95% CI, 1.24-3.94), and 3 other factors (eg, discharge to nursing home; HR, 1.61; 95% CI, 1.33-1.95) were associated with readmission. Conclusions: Readmission following noncardiac surgery is common (1 in 13 patients). We identified perioperative risk factors associated with 30-day readmission that can help frontline clinicians identify which patients are at the highest risk of readmission and target them for preventive measures.

Mortality and reintervention following elective abdominal aortic aneurysm repair.

BACKGROUND: The objective of this study is to provide an up-to-date meta-analysis on the short- and long-term mortality rates of elective repair of abdominal aortic aneurysms (AAAs) via the open and endovascular approaches. METHODS: MEDLINE, EMBASE, and Cochrane Central Register of Controlled trials, conference proceeding from major vascular meetings were searched for randomized trials comparing open vs elective endovascular aneurysm repair (EVAR) of AAAs. A random-effects model was used for analysis. Risk ratio (RR) and 95% confidence intervals (CIs) of open vs EVAR were calculated for short- and long-term mortality and reintervention rates. RESULTS: The analysis encompassed four randomized controlled trials with a total of 2783 patients. The open repair group resulted in significantly increased 30-day postoperative all-cause mortality compared with EVAR repair group (3.2% vs 1.2%; RR, 2.81; 95% CI, 1.60-4.94); however, there is no statistical difference in the long-term all-cause mortality between both groups (RR, 0.97; 95% CI, 0.86-1.10). Interestingly, fewer patients underwent reintervention procedures in the open repair group compared with those who had EVAR repair (9.3% vs 18.9%; RR, 0.49; 95% CI, 0.40-0.60), but this finding is doubtful due to the large heterogeneity. Lastly, no statistical difference in long-term mortality rates attributable to cardiovascular disease (CVD), aneurysm related, or stroke were found between the two types of repair. CONCLUSIONS: Results of this meta-analysis demonstrate that the 30-day all-cause mortality rate is higher with open than with EVAR repair; however, there is no statistical difference in the long-term all-cause and cause-specific mortality between both groups. The reintervention rate attributable to procedural complication was higher in the EVAR group. Because of the equivalency of long-term outcomes and the short-term benefits of EVAR, an endovascular-first approach to AAAs can be supported by the meta-analysis.

Aortic dissection and accelerated aneurysmal degeneration in a patient with giant cell arteritis.

Giant cell arteritis (GCA) is associated with nonatheromatous aortic pathology. Here we present a case in which a 76-year-old woman with a biopsy-proven history of GCA and a previous repair of her ascending aortic aneurysm presents with an acute dissection of a 4-cm aneurysm in the descending thoracic aorta. It was treated using endovascular techniques. This report adds to a growing body of evidence that GCA is a risk factor for aortic dissection and nonatheromatous aortic aneurysms.

A comparison of duplex ultrasound findings after cyanoacrylate embolization versus endovenous laser ablation of the great saphenous vein.

BACKGROUND: Whereas numerous studies have demonstrated noninferiority of cyanoacrylate embolization (CAE) relative to endovenous laser ablation (EVLA), little is known about the natural history of the vein or the glue that is implanted. This study provides the first description of duplex ultrasound changes of the great saphenous vein (GSV) after CAE relative to EVLA as well as a pragmatic view of outcomes in clinical practice. METHODS: Patients treated with CAE and EVLA at our institution were matched by time of procedure and vein size. GSV diameter was measured at the saphenofemoral junction, midthigh, and knee. Duplex ultrasound imaging was repeated after treatment in the same noninvasive laboratory with an identical protocol. Clinical data were collected by retrospective chart review. RESULTS: Of 481 eligible patients, 119 underwent postoperative duplex ultrasound imaging. Although there was a trend toward decreased vein diameter over time in CAE patients relative to their preoperative vein diameter, this failed to reach statistical significance at the midthigh (P = .32) or at the knee (P = .511). In EVLA patients, as follow-up interval increased, the vein was less frequently visualized on ultrasound at the midthigh (P = .046) and knee (P = .038). At >2 years of follow-up, >80% of EVLA patients had no visible vein segment. Anatomic recurrence was observed in 10.5% of CAE patients and 8.2% of EVLA patients, which was not statistically significantly different (P = .60). The majority of recurrence was observed in the presence of incompetent tributaries. CONCLUSIONS: After CAE of the GSV, our results indicate that the glue cast remains for at least 3 years. Although our results suggest that the glue is broken down over time, this process is much slower than expected. In contrast, after EVLA, the vein tissue is remodeled and is no longer visible with time. In our study, which represents a pragmatic clinical population with a large (median, 9.2 mm) vein diameter, we again demonstrate no statistically significant difference in recurrence rates. Whereas CAE offers an attractive treatment option for GSV incompetence, the glue cast remains for a prolonged time, and longer follow-up studies than those currently available are indicated.

Blunt innominate artery trauma requiring repair and carotid ligation.

Traumatic dissection of the innominate artery is a rare clinical entity. Management of a patient with motorsensory compromise and dissection extending to the subclavian and right common carotid arteries is quite rare and can be quite involved. Here we present such a case and discuss the unique peri-operative decision-making in the context of what is reported in the literature. Restoration of motorsensory function is critical and in this case, requiring a multi-disciplinary team.

Anaconda endovascular limbs for the treatment of isolated iliac artery aneurysms.

The purpose of this article is to report the feasibility and preliminary results of the treatment of isolated iliac artery aneurysms (IAAs) with Anaconda limbs (Vascutek Ltd., Inchinnan, Renfrewshire, Scotland). A prospective cohort is reported of consecutive IAAs treated by two senior surgeons from May to December 2006. One or more Anaconda limbs were used, and internal iliac arteries were embolized if necessary. Twelve IAAs in 11 patients were treated. The average IAA diameter was 4.3 +/- 1.1 cm, and the average diameter of stent used was 14 +/- 2.5 mm, with an average total length of 97 +/- 25 mm. At a mean follow-up of 12 +/- 4 months, there were no graft-related complications, graft occlusions, or requirements for reintervention. Endovascular treatment for isolated IAAs under local anesthesia using Anaconda limbs is feasible, safe, and effective. However, as with all new technology, longer follow-up data are necessary.

Impact of lymph node retrieval and pathological ultra-staging on the prognosis of stage II colon cancer.

BACKGROUND AND OBJECTIVES: A minimum number of lymph nodes must be assessed for accurate diagnosis of stage II colon cancer. We assessed number of lymph nodes retrieved, pathological ultra-staging, and outcome in stage II colon cancer. MATERIALS AND METHODS: Consecutively treated patients with stage II colon cancer were identified. Baseline and outcome data were collected. Retrospective ultra-staging using lymphovascular invasion (LVI) and nodal micrometastases was performed. Patients were divided into two groups: group I had 6 nodes retrieved. Survival was analyzed. RESULTS: One hundred and fifteen patients were included in the study. The 5 year overall survival was worse in group I versus II (P = 0.03). LVI and micrometastases were identified but neither predicted survival. Disease failure in group I was due to distant metastases rather than local recurrence. CONCLUSIONS: Inadequate retrieval and assessment of lymph nodes is associated with worse outcome in stage II colon cancer patients. Recurrence patterns support the hypothesis that disease recurrence occurred due to inaccurate staging. In this small study, LVI or nodal micrometastases did not predict survival. Maximal attention should be paid to the total number of lymph nodes retrieved before embarking on potentially more resource intensive staging methods.