Outcomes of prosthetic upper arm arteriovenous graft vs brachiobasilic fistula for hemodialysis access.

OBJECTIVE: Primary arteriovenous access such as radiocephalic and brachiocephalic fistulas are initial choices for creating vascular access in dialysis patients. When neither of these choices is an option, upper arm arteriovenous graft or brachiobasilic transposition is recommended. Although primary fistula is better than prosthetic graft for suitable patients, there is little data to guide the best treatment strategy in the absence of suitable vein for primary access creation. This study identifies factors that influence patency rates and compares outcomes of patients treated with brachiobasilic fistula vs upper arm graft in patients who have failed forearm access or are not candidates for primary access. METHODS: A prospectively maintained database of patients with dialysis-dependent renal failure from 2010 to 2022 was analyzed. Primary, primary assisted, and secondary patency rates were calculated. Incidence rates of complications and reinterventions were compared. RESULTS: There were 148 patients with brachiobasilic fistulas and 157 patients with upper arm grafts. The graft group was older (70.1 ± 14.7 vs 62.5 ± 14.6 years; P = .003) and had a higher incidence of pacemakers (11.9% vs 4.1%; P = .005). Brachiobasilic fistulas had higher 6-month (77.0% vs 64.3%; P = .02) and 1-year (68.2% vs 55.4%; P = .03) primary-assisted patency. Secondary patency rates were better for upper arm grafts at 1-year (82.2% vs 72.3%; P = .05). Access complications of non-maturation and aneurysm were higher in basilic vein transposition (21.6% vs 1.3%; P < .0001; 15.5% vs 6.4%; P = .017). Grafts had higher rates of occlusion (58.0% vs 25.7%; P < .0001). In terms of interventions, upper arm grafts had higher rates of thrombectomy (50.3% vs 18.9%; P < .0001), but there was no difference seen in angioplasty, stent, surgical revision, or steal procedures. Basilic vein transpositions had longer time to cannulation (104.6 ± 81.1 vs 32.5 ± 22.4 days; P < .0001), longer total catheter days (251.1 ± 181.7 vs 72.9 ± 56.3 days; P < .0001), and higher number of procedures to aid maturity (0.7 ± 0.7 vs 0.1 ± 0.3; P < .0001). CONCLUSIONS: In this retrospective analysis, when forearm access or primary arteriovenous access is not an option, basilic vein transposition and upper arm grafts have fairly equivalent primary patency. Primary assisted patency is slightly better in basilic vein fistulas, but secondary patency is better in upper arm grafts at 1 year. Basilic fistulas also had longer time to cannulation, longer total catheter days, and more procedures to aid maturity.

Postoperative Outcomes and One-Year Mortality of Patients on Chronic Anticoagulation Medications Undergoing Infrainguinal Bypass.

BACKGROUND: Patients requiring open infrainguinal bypass (IIB) frequently are taking chronic anticoagulation (AC) medications. Taking these medications in the preoperative setting may affect the outcomes of surgery. This study aims to evaluate postoperative outcomes and 1-year mortality of patients taking chronic AC medications that undergo IIB. METHODS: Using data obtained from the Vascular Quality Initiative from January 2011 to October 2021, patients on warfarin or any direct oral anticoagulants (DOAC) within 30 days of IIB were compared with patients not taking chronic AC medications. The primary outcomes were in-hospital, 30-day, and 1-year mortality. The secondary outcomes included total procedure time, need for perioperative packed red blood cell transfusion, prolonged length of hospital stay, postoperative myocardial infarction or stroke, and graft patency at discharge. A subgroup analysis was performed comparing patients taking warfarin with those taking DOACs. Univariate analyses and multivariate logistic regression, Kaplan Meier survival, and Cox regression analyses were used to analyze the data for postoperative and 1-year outcomes, respectively. RESULTS: A total of 55,076 patients underwent IIB during the study period, and 11,547 (20.97%) were on chronic AC prior to surgery. The 2 cohorts differed significantly in almost every demographic and clinical characteristic. Multivariate analyses adjusting for 45 potential confounders revealed that there was no significant difference in in-hospital, 30-day, and 1-year mortality. The total procedure time for the chronic AC cohort was on average 11.46 ± 2.16 min longer (P ≤ 0.001) and there was a greater risk of prolonged length of stay in the hospital (adjusted odds ratio [aOR]: 1.19, 95% confidence interval [CI]: 1.13-1.26, P < 0.001). These patients also returned to the operating room (OR) at a greater rate (aOR: 1.12, 95% CI: 1.05-1.19; P = 0.016) and demonstrated a significantly lower rate of graft patency at discharge (aOR: 0.73, 95% CI: 0.62-0.86, P = 0.001). On subgroup analysis, multivariate analysis demonstrated lower 30-day mortality for the DOAC group in comparison to the warfarin group (aOR: 0.74, 95% CI: 0.57-0.94, P = 0.015), but no significant differences in in-hospital and 1-year mortality. CONCLUSIONS: Patients taking AC medications within 30 days prior to IIBs may require more perioperative red blood cell transfusions, longer hospitalizations, and return to the OR at a greater rate. They are also at an increased risk for loss of graft patency at discharge. However, these patients are not at increased risk of in-hospital, 30-day, or 1-year mortality. IIB can, therefore, be performed safely in patients taking chronic AC medications.

Preoperative thrombolysis is associated with improved vein patency and functional outcomes after first rib resection in acute Paget-Schroetter syndrome.

INTRODUCTION: Most patients with acute Paget-Schroetter syndrome (PSS) present in one of two manners: (1) thrombosis managed initially with thrombolysis and anticoagulation and then referred for surgery, and (2) initial treatment with anticoagulation only and later referral for surgery. Definitive benefits of thrombolysis in the acute period (the first 2 weeks after thrombosis) over anticoagulation alone have not been well reported. Our goal was to compare patients managed with early thrombolysis and anticoagulation followed by first rib resection (FRR) and later postoperative venography with venoplasty (PTA) with those managed with anticoagulation alone followed by FRR and PTA using vein patency assessed with venography and standardized outcome measures. METHODS: We reviewed a prospectively collected database from 2000 to 2019. Two groups were compared: those managed with early thrombolysis at our institution (Lysis) and those managed with anticoagulation alone (NoLysis). All patients underwent FRR. Venography was routinely performed before and after FRR. Standardized outcome measures included Quick Disability of Arm, Shoulder, and Hand (QuickDASH) scores and Somatic Pain Scale. RESULTS: A total of 50 Lysis and 50 NoLysis patients were identified. Pre-FRR venography showed that thrombolysis resulted in patency of 98% of veins, whereas 78% of NoLysis veins were patent. After FRR, postoperative venography revealed that 46 (92%) patients in the Lysis group and 37 (74%) patients in the NoLysis group achieved vein patency. Thrombolysis was significantly associated with final vein patency (odds ratio: 17 [4-199]; P < .001). Lysis patients had a trend toward lower QuickDASH scores from pre-FRR to post-FRR compared with NoLysis patients with a mean difference of -16.4 (±19.7) vs -5.2 (±15.6) points (P = .13). The difference in reduction of Somatic Pain Scale scores was not statistically significant. CONCLUSIONS: Thrombolysis as initial management of PSS, combined with anticoagulation, followed by FFR and VenoPTA resulted in improved final vein patency and may lead to an improved functional outcome measured with QuickDASH scores. Therefore, clinical protocols using thrombolysis as initial management should be considered when planning the optimal treatment strategy for patients with acute PSS.

In-situ bypass is associated with superior infection-free survival compared with extra-anatomic bypass for the management of secondary aortic graft infections without enteric involvement.

OBJECTIVE: The optimal revascularization modality following complete resection of aortic graft infection (AGI) without enteric involvement remains unclear. The purpose of this investigation is to determine the revascularization approach associated with the lowest morbidity and mortality using real-world data in patients undergoing complete excision of AGI. METHODS: A retrospective, multi-institutional study of AGI from 2002 to 2014 was performed using a standardized database. Baseline demographics, comorbidities, and perioperative variables were recorded. The primary outcome was infection-free survival. Descriptive statistics, Kaplan-Meier survival analysis, and univariate and multivariable analyses were performed. RESULTS: A total of 241 patients at 34 institutions from seven countries presented with AGI during the study period (median age, 68 years; 75% male). The initial aortic procedures that resulted in AGI were 172 surgical grafts (71%), 66 endografts (27%), and three unknown (2%). Of the patients, 172 (71%) underwent complete excision of infected aortic graft material followed by in situ (in-line) bypass (ISB), including antibiotic-treated prosthetic graft (35%), autogenous femoral vein (neo-aortoiliac surgery) (24%), and cryopreserved allograft (41%). Sixty-nine patients (29%) underwent extra-anatomic bypass (EAB). Overall median Kaplan-Meier estimated survival was 5.8 years. Perioperative mortality was 16%. When stratified by ISB vs EAB, there was a significant difference in Kaplan-Meier estimated infection-free survival (2910 days; interquartile range, 391-3771 days vs 180 days; interquartile range, 27-3750 days; P < .001). There were otherwise no significant differences in presentation, comorbidities, or perioperative variables. Multivariable Cox regression showed lower infection-free survival among patients with EAB (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.6-3.6; P < .001), polymicrobial infection (HR, 2.2; 95% CI, 1.4-3.5; P = .001), methicillin-resistant Staphylococcus aureus infection (HR, 1.7; 95% CI, 1.1-2.7; P = .02), as well as the protective effect of omental/muscle flap coverage (HR, 0.59; 95% CI, 0.37-0.92; P = .02). CONCLUSIONS: After complete resection of AGI, perioperative mortality is 16% and median overall survival is 5.8 years. EAB is associated with nearly a two and one-half-fold higher reinfection/mortality compared with ISB. Omental and/or muscle flap coverage of the repair appear protective.

Midterm Results of the Supera Stent for the Treatment of Femoropopliteal Occlusive Disease.

BACKGROUND: The Supera (Abbott Vascular, Santa Clara, CA) stent is an interwoven nitinol, shape-memory stent with high strength and flexibility characteristics which are purported to increase resistance to kinking and compression. The purpose of this study was to review single-center outcomes of the use of this stent in the femoropopliteal segment. METHODS: We performed a single-center, retrospective analysis of patients who underwent Supera stent placement for femoropopliteal occlusive disease from 2016-2019. Data was collected on patient demographics and procedural details. Follow-up imaging data, including duplex imaging and ankle-brachial indices, and clinical data were abstracted from encounter notes. RESULTS: Sixty-two patients with 72 unique Supera stent placements were identified. Mean age was 76 and 69% were male. 56% of patients had severe calcification and 11% had moderate calcification. 48% of lesions were Trans-Atlantic Inter-Society Consensus Document C or D lesions. Primary patency rates at 12, 24, and 36 months were 85%, 82%, and 75%, respectively. Primary patency was not affected significantly by lesion length, degree of calcification, number of outflow vessels, concomitant interventions, or stent size. CONCLUSIONS: These results demonstrate sustained primary patency with the Supera stent over a 3-year interval in treatment of patients with femoropopliteal occlusive disease, including in the setting of severely calcified vessels.

Nationwide comparison of the medical complexity of patients by surgical specialty.

OBJECTIVE: Intuitively, the chronic disease burden of surgical patients varies considerably by surgical specialty, although sparse evidence in the literature supports this notion. We sought to characterize the medical complexity of surgical patients by surgical specialty and to quantify the association between medical complexity and outcomes. METHODS: The National Inpatient Sample, an all-payer inpatient database representative of 97% of all U.S. hospitalizations, was used to identify adults undergoing surgery between 2005 and 2014. The most commonly performed operations that constituted 80% of each surgical specialty's practice were abstracted. The previously validated Elixhauser Comorbidity Index (ECI) was calculated per year by surgical specialty as a measure of medical complexity. Outcomes and resource utilization were assessed by comparing mortality rate, length of stay, and cost. RESULTS: An estimated 53,232,144 patients underwent operations in one of nine surgical specialty categories. Surgical specialties were ranked by ECI, with cardiac surgery (3.56), vascular surgery (3.49), and thoracic surgery (2.86) having the highest mean ECI (all P values <.0001 compared with vascular surgery). Whereas the high ECI scores in cardiac surgery were driven by arrhythmias and hypertension, vascular patients had a more uniform distribution of comorbidities. The average ECI for all surgical patients increased during the study period from 2.03 in 2005 to 2.65 in 2014 (P < .001), with a similar trend for all specialties considered. Unlike the two specialties with the lowest burden of comorbidities (orthopedic surgery and endocrine surgery), cardiac surgery and vascular surgery exhibited significantly higher inpatient mortality, LOS, and costs. CONCLUSIONS: Although all surgical patients have exhibited an increase in comorbidities during the past decade, candidates for cardiac and vascular operations appear to carry the largest burden of chronic conditions. Despite caring for patients with the highest burden of comorbidities for emergent operations, vascular surgery did not have the highest mortality, inpatient costs, or length of stay compared with some of the other specialties. The intensity of care and assumed risk in treating medically complex vascular patients should be taken into consideration in deciding health policy, reimbursement, and hospital resource allocation.

Trainee Experience in Simulation-Based Education of Open Vascular Surgery.

BACKGROUND: Simulation continues to be an important adjunct to vascular surgery training, yet the optimal implementation of simulation to complement conventional surgical training continues to evolve. This study aims to find areas for improvement in current simulation-based training of open vascular skills by characterizing the experience of vascular trainees attending a national simulation-based course. METHOD: This was a survey study conducted at the simulation course of the Annual UCLA/SVS Symposium: A Comprehensive Review and Update of What's New in Vascular and Endovascular Surgery, a national vascular surgery meeting. The survey consisted of 17 questions and was administered on paper or electronically via the Audience Response System, before the start of the course. The survey assessed the participants' experience in formal training, simulation training, and comfort with open surgical procedures. RESULTS: Between 2013 and 2018, the survey was completed by 150 participants of which 65% were vascular fellows. Only 48% of the participants had formal training in suturing and surgical instruments. Most participants had formal training in basic vascular techniques and advanced vascular operations. In 71%, simulation was incorporated into basic technique training and 60% in open surgical training. Simulation training was most commonly utilized in learning anastomotic techniques and open abdominal aortic aneurysm repair. Simulation skills were deemed translatable to the operating room by 59% of participants. Most participants were comfortable performing open vascular procedures. However, 68% of participants were uncomfortable performing an abdominal aortic aneurysm repair. CONCLUSIONS: There continues to be a significant portion of trainees who do not undergo a simulation-based education. Current simulation training is being targeted to meet trainee needs in open vascular surgery, specifically open aneurysm repair. Nonetheless, trainees continue to have doubts regarding applicability of simulation-based skills to the operating theater. Further studies investigating access to simulation education as well as its translatability are needed.

Investigating uncommon vascular diseases using the Vascular Low Frequency Disease Consortium.

BACKGROUND: Standardized databases such as the Vascular Quality Initiative and National Surgical Quality Improvement Project assess the quality of care related to common vascular surgery procedures, but are not designed for uncommon vascular diseases. We describe a method of assessing uncommon vascular diseases using a multi-institutional collaboration, the Vascular Low Frequency Disease Consortium (VLFDC). METHODS: Uncommon vascular diseases are identified through a systematic literature review. A disease-specific database is developed and tested at a single institution, then refined and circulated to participating VLFDC investigators. Detailed inclusion and exclusion criteria and data point definitions are provided, allowing for standardized data collection across institutions. Each participating institution identifies all patients over a specific time period and enters the data into a VLFDC-provided database. The data are then de-identified and transmitted to our centralized data center for analysis. RESULTS: Since 2003, the VLFDC has conducted and published nine studies and enrolled 4532 patients, involving 232 institutions and 271 investigators. The studies include renal artery aneurysms, isolated femoral artery aneurysms, spontaneous mesenteric dissection, adventitial cystic disease, carotid body tumors, and vascular Ehlers-Danlos syndrome. Each published study reported on a minimum of 10 times the number of patients collected in previously published studies over the same time period, allowing stronger conclusions to be drawn from the larger sample size. Each study both confirmed previous management principles, which were based on small single-institution experiences, and challenged conventional management paradigms. CONCLUSIONS: When only small clinical series exist to provide guidance in managing uncommon vascular diseases, and/or where conflicting recommendations are made on the treatment of uncommon vascular diseases, a multi-institutional consortium can provide high-volume standardized data that either confirm or changes prior management principles.

Caval Reconstruction with Undersized Ringed Graft after Resection of Inferior Vena Cava Leiomyosarcoma.

BACKGROUND: The en bloc resection of inferior vena cava (IVC) leiomyosarcoma often necessitates IVC reconstruction. The objective of this study is to examine outcomes after IVC reconstruction and determine optimal graft sizing. METHODS: A retrospective review was conducted of all IVC reconstructions after IVC leiomyosarcoma resection at a single institution. Cross-sectional dimensions at the IVC resection margins were measured on preoperative imaging. The tumor location was based on the most superiorly involved region of the IVC and was classified as infrarenal, between hepatic and renal veins, or superior to the hepatic veins. Perioperative details and long-term outcomes including graft sizing, graft patency, morbidity, and mortality were recorded. RESULTS: Between 2007 and 2017, 12 patients (6 females, mean age: 64.5 years, age range: 46-80 years) underwent IVC leiomyosarcoma resection and reconstruction. All reconstructions were performed with ringed polytetrafluoroethylene (PTFE); graft sizes ranged from 12 mm to 16 mm. The tumor location was exclusively infrarenal in seven patients, between the renal and hepatic veins in two patients, and involved multiple segments in three patients. Larger graft sizes were utilized in reconstructing more superior segments of the IVC. Grafts were typically undersized and based on the diameter of the superior resection margin with 12 mm grafts approximately correlating to a 20 mm diameter, 14 mm to 25 mm, and 16 mm to 30 mm. The average undersizing ratio was 0.6. At a mean follow-up time of 43 ± 27 months, radiographic graft patency was 92%, overall survival was 83%, and disease-free survival was 25%. CONCLUSIONS: After en bloc resection of IVC leiomyosarcoma, caval reconstruction with an undersized ringed PTFE has acceptable patency. Grafts sizes should be based on the IVC diameter superior to the tumor and undersizing by approximately 40% appears to be associated with acceptable patency rates. Further multiinstitutional studies should be performed to best determine the optimal treatment of this rarely encountered tumor.

Comparison of one-stage and two-stage upper arm brachiobasilic arteriovenous fistula in the Vascular Quality Initiative.

OBJECTIVE: An upper arm brachiobasilic arteriovenous fistula (BBAVF) is a reliable autogenous hemodialysis access created with a one-stage or two-stage technique. Although both techniques are variably used, the optimal approach is uncertain. In this study, we compared the outcomes of one-stage and two-stage BBAVF procedures. METHODS: We identified 2648 patients who had received BBAVFs within the Vascular Quality Initiative data set (2010-2016) and compared those created using the one-stage and two-stage technique. The primary outcome measures were primary and secondary patency rates at 12 months. Other outcomes assessed were wound infection, steal, and swelling at 3 months. The log-rank test was used to evaluate patency by Kaplan-Meier analysis. Cox proportional hazards models were used to examine the adjusted association between surgical technique and outcomes. RESULTS: There were 1234 (47%) one-stage and 1414 (53%) two-stage BBAVFs in the study cohort, including 1848 (70%) patients who were on dialysis at the time of surgery and 1795 (68%) patients with a history of previous access. Patients who underwent a one-stage BBAVF were more likely to be male (54% vs 45%; P < .001), to be white (60% vs 41%; P < .001), and to have a history of coronary artery disease (22% vs 17%; P = .001). Patients undergoing one-stage BBAVFs have larger vein diameters (4.1 vs 3.4 mm; P < .001) and have the procedure in an inpatient setting (21% vs 13%; P < .001) compared with patients undergoing a two-stage procedure. The 12-month primary patency rate was higher for the one-stage BBAVF (49.1% vs 40.4%; P = .005), although the secondary patency rate was comparable (80.0% vs 77.9%; P = .54). Postoperative bleeding (4% vs 1.5%; P < .001), wound infection (1.01% vs 0.4%; P = .047), and arm swelling (2.1 % vs 0.8%; P = .006) were higher for one-stage BBAVFs. In multivariable analysis, although loss of primary patency at 12 months (adjusted hazard ratio [aHR], 1.12; 95% confidence interval [CI], 0.97-1.30; P = .12) and 3-month wound infection (aHR, 0.42; 95% CI, 0.14-1.25, P = .12) were similar between the two approaches, the risk of 3-month arm swelling was significantly lower for two-stage BBAVFs (aHR, 0.35; 95% CI, 0.16-0.77; P = .009). CONCLUSIONS: Whereas surgeons were more likely to perform a two-stage BBAVF in patients with a history of previously failed access and smaller basilic vein, our data show no difference in primary or secondary patency of one-stage and two-stage BBAVFs at 12 months.

Risk stratification for the development of respiratory adverse events following vascular surgery using the Society of Vascular Surgery's Vascular Quality Initiative.

OBJECTIVE: Postoperative respiratory adverse events (RAEs) are associated with high rates of morbidity and mortality in general surgery, however, little is known about these complications in the vascular surgery population, a frail subset with multiple comorbidities. The objective of this study was to describe the contemporary incidence of RAEs in vascular surgery patients, the risk factors for this complication, and the overall impact of RAEs on patient outcomes. METHODS: The Vascular Quality Initiative was queried (2003-2014) for patients who underwent endovascular abdominal aortic repair, open abdominal aortic aneurysm repair, thoracic endovascular aortic repair, suprainguinal bypass, or infrainguinal bypass. A mixed-effects logistic regression model determined the independent risk factors for RAEs. Using a random 85% of the cohort, a risk prediction score for RAEs was created, and the score was validated using the remaining 15% of the cohort, comparing the predicted to the actual incidence of RAE and determining the area under the receiver operating characteristic curve. The independent risk of in-hospital mortality and discharge to a nursing facility associated with RAEs was determined using a mixed-effects logistic regression to control for baseline patient characteristics, operative variables, and other postoperative adverse events. RESULTS: The cohort consisted of 52,562 patients, with a 5.4% incidence of RAEs. The highest rates of RAEs were seen in current smokers (6.1%), recent acute myocardial infarction (10.1%), symptomatic congestive heart failure (9.9%), chronic obstructive pulmonary disease requiring oxygen therapy (11.0%), urgent and emergent procedures (6.4% and 25.9%, respectively), open abdominal aortic aneurysm repairs (17.6%), in situ suprainguinal bypasses (9.68%), and thoracic endovascular aortic repairs (9.6%). The variables included in the risk prediction score were age, body mass index, smoking status, congestive heart failure severity, chronic obstructive pulmonary disease severity, degree of renal insufficiency, ambulatory status, transfer status, urgency, and operative type. The predicted compared with the actual RAE incidence were highly correlated, with a correlation coefficient of 0.943 (P < .0001) and a c-statistic = 0.818. RAEs had a significantly higher rates of in-hospital mortality (25.4% vs 1.2%; P < .0001; adjusted odds ratio, 5.85; P < .0001), and discharge to a nursing facility (57.8% vs 19.0%; P < .0001; adjusted odds ratio, 3.14; P < .0001). CONCLUSIONS: RAEs are frequent and one of the strongest risk factors for in-hospital mortality and inability to be discharged home. Our risk prediction score accurately stratifies patients based on key demographics, comorbidities, presentation, and operative type that can be used to guide patient counseling, preoperative optimization, and postoperative management. Furthermore, it may be useful in developing quality benchmarks for RAE following major vascular surgery.

Comparative effectiveness of anticoagulation on midterm infrainguinal bypass graft patency.

OBJECTIVE: Therapeutic anticoagulation (AC) is used clinically for prolongation of infrainguinal bypass patency, but evidence for the efficacy of this practice is conflicting. The objective of our study was to determine the association of AC with bypass graft primary patency. METHODS: Clinical and comorbid data of patients undergoing infrainguinal bypass grafts to a below-knee target with at least 1 year of follow-up performed from 2003 to 2015 were obtained from the Society for Vascular Surgery Vascular Quality Initiative. Inverse propensity of treatment-weighted Cox regression was used to assess the effect of AC on patency in the total cohort while adjusting for clinical, operative, and comorbid differences between treatment groups. Subgroup analyses of distal targets and conduit type were performed. Perioperative complications were analyzed using propensity-weighted logistic regression. RESULTS: We identified 7612 bypass grafts with intact 1-year follow-up information from 2003 to 2015. The mean age was 67.5 ± 11.2 years; 30.5% (n = 2320) were female, and 28.6% (n = 2165) were discharged on therapeutic AC. The anticoagulated group had a higher rate of tibial, ankle, and pedal targets (52.1% [n = 1127] vs 47.6% [n = 2269]; P < .001), had a greater use of non-single-segment vein conduits (44.3% [n = 951] vs 26.5% [n = 1426]; P < .001), and was more likely to have had a previous ipsilateral bypass (27.2% [n = 589] vs 14.7% [n = 794]; P < .001) or stent (25.4% [n = 550] vs 20.9% [n = 1130]; P < .001). Estimated unadjusted primary patency was 70.8% ± 0.6% at 1 year and lower for anticoagulated bypasses (66.9% ± 1.2% vs 72.4% ± 0.7%; P < .001). Propensity-weighted analysis showed no significant association of AC with primary patency in the overall cohort (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.86-1.11; P = .8) but demonstrated a trend toward improvement of primary patency in those with a non-single-segment vein conduit to a below-knee popliteal target (HR, 0.85; 95% CI, 0.80-1.02; P = .09). AC was associated with significantly improved secondary patency in those with prosthetic bypass grafts (HR, 0.77; 95% CI, 0.62-0.96; P = .02) or prosthetic bypasses to an infrapopliteal target (HR, 0.72; 95% CI, 0.54-0.97; P = .02). Odds of postoperative wound complications were significantly higher in those receiving AC (odds ratio, 1.33; 95% CI, 1.11-1.61; P = .002). CONCLUSIONS: This study does not demonstrate a significant impact of therapeutic AC on primary patency for infrainguinal bypass grafts. Treatment with AC may benefit secondary patency in those with a prosthetic bypass, especially to an infrapopliteal target, but at an increased risk of postoperative wound complications.

Early extubation is associated with reduced length of stay and improved outcomes after elective aortic surgery in the Vascular Quality Initiative.

OBJECTIVE: Timing of extubation after open aortic procedures varies across hospitals. This study was designed to examine extubation timing and determine its effect on length of stay (LOS) and respiratory complications after elective open aortic surgery. METHODS: We studied extubation timing for 7171 patients undergoing elective open abdominal aortic aneurysm repair (2687 [37.5%]) or suprainguinal bypass for aortoiliac occlusive disease (4484 [62.5%]) from October 2010 to April 2015 in hospitals participating in the Vascular Quality Initiative (VQI). Our primary outcome was prolonged LOS (>7 days), and the secondary outcome was respiratory complications (pneumonia or reintubation). The association between extubation timing and outcomes was assessed using multivariable logistic regression mixed-effects models that adjusted for confounding factors at the patient and procedure level. A variable importance analysis was conducted using a chi-pie framework to identify factors contributing to the variability of extubation timing. RESULTS: The 7171 patients undergoing abdominal aortic surgery were a mean age of 65.4 (standard deviation, 10.2) years, and 63% were male. Extubation occurred (1) in the operating room (76.3%), (2) <12 hours (10.9%), (3) 12 to 24 hours (7.2%), or (4) >24 hours (5.6%) after surgery. Hospitals in the top quartile for case volume had the highest percentage of patients extubated in the operating room (82.8%). Patients least likely to be extubated in the operating room were older, more likely to have chronic obstructive pulmonary disease, require vasopressors, have higher estimated blood loss (EBL), and longer procedure times. After adjustment for patient, procedure, and institutional factors, delayed extubation was associated with prolonged LOS (<12 hours: odds ratio [OR], 1.4; 95% confidence interval [CI], 1.2-1.7; 12-24 hours: OR, 2.1; 95% CI, 1.7-2.7; >24 hours: OR, 5.3; 95% CI, 4.0-6.9), and pulmonary complications (<12 hours: OR, 1.9; 95% CI, 1.4-2.6; 12-24 hours: OR, 2.6; 95% CI, 1.8-3.6; >24 hours: OR, 9.6; 95% CI, 7.1-13.0) compared with those extubated in the operating room. Subset analysis of patients extubated in the operating room or <12 hours showed that extubation out of the operating room was associated with prolonged LOS (OR, 1.4; 95% CI, 1.2-1.7) and pulmonary complications (OR, 1.8; 95% CI, 1.3-2.5). The variable importance analysis demonstrated that EBL (26%) and procedure time (24%) accounted for half of the variation in extubation timing. CONCLUSIONS: Extubation in the operating room is associated with shorter LOS and morbidity after open aortic surgery. EBL, procedure time, and center variation account for variability in extubation timing. These data advocate for standardized perioperative respiratory care to reduce variation, improve outcomes, and reduce LOS.

Contemporary outcomes of open complex abdominal aortic aneurysm repair.

OBJECTIVE: The recent commercial availability of fenestrated stent grafts is likely to result in increasing endovascular repair of complex (juxtarenal and suprarenal) abdominal aortic aneurysms (cAAAs). Whereas most studies providing benchmarking for outcomes after open repair have been from high-volume centers, we sought to evaluate outcomes after elective open cAAA repair vs infrarenal AAA repair at a regional level. METHODS: We used the Vascular Study Group of New England registry, which recorded 1875 open AAA repairs in New England from 2003 to 2011. Data from 14 hospitals performing both AAA and cAAA repair were used to assess the impact of clinical and technical factors on outcomes of cAAA repair. RESULTS: There were 443 patients who had elective cAAA repair as defined by use of a suprarenal (n = 340; 77%) or supraceliac (n = 103; 23%) clamp, with median survival follow-up of 35 months (interquartile range, 47 months). Compared with AAA repair, patients undergoing cAAA repair were more likely to be female; to have hypertension, congestive heart failure, or chronic obstructive pulmonary disease; and to have a higher baseline creatinine concentration. cAAA cases were repaired through a retroperitoneal incision in 40% of cases, with hypothermic renal perfusion use in 15%, mannitol in 73%, and renal bypass in 13%, with wide variability in the application of these adjuncts. Complex aneurysm repair vs routine AAA repair was associated with a higher independent risk of 30-day mortality (3.6% vs 1.2%; P = .002), respiratory complications (19% vs 10%; P < .001), and renal complications (21% vs 8.7%; P < .001). Among all patients, the only independent clinical or technical predictors of 30-day mortality were preoperative coronary artery disease (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.1-5.4; P = .02) and amount of intraoperative blood transfusion (OR, 2.8; 95% CI, 1.3-6.2; P = .01). In the subgroup undergoing cAAA repair, there were no predictors of operative mortality. Renal or visceral ischemia time was the only technical factor during cAAA repair that independently predicted cardiac (OR, 1.01; 95% CI, 1.00-1.03; P = .04), respiratory (OR, 1.03; 95% CI, 1.01-1.04; P < .001), and renal (OR, 1.03; 95% CI, 1.02-1.05; P < .001) complications. Long-term survival for cAAA patients was 91% ± 1% at 1 year and 71% ± 3% at 5 years and not different from that of patients undergoing infrarenal AAA repair. Risk-adjusted predictors of late mortality after cAAA repair included age (hazard ratio [HR], 1.08; 95% CI, 1.04-1.11; P < .001), chronic obstructive pulmonary disease (HR, 1.9; 95% CI, 1.2-3.0; P = .008), and preoperative creatinine concentration (per mg/dL; HR, 1.8; 95% CI, 1.05-2.9; P = .03). CONCLUSIONS: These data highlight excellent operative outcomes for open cAAA repair across the New England region despite significant variation in operative conduct across hospitals. Patients tolerating cAAA repair have durable long-term survival.

Contemporary Management of Acute Aortic Occlusion Has Evolved but Outcomes Have Not Significantly Improved.

BACKGROUND: Most existing series of acute aortic occlusion (AAO) predate the changes in surgical and endovascular therapy of the last 2 decades. We examined the contemporary management and outcomes of AAO. METHODS: We reviewed consecutive patients with AAO at a tertiary referral center from 2004 to 2012. Outcomes were stratified and compared according to etiology and procedure performed. RESULTS: AAO in 29 patients was due to in situ thrombosis in 21 (72%) and embolism in 8 (28%) patients. Vascular patients with embolism were on average older (77 ± 7 vs. 66 ± 12 years, P = 0.02) and had higher rates of atrial fibrillation (100% vs. 20%, P = 0.0002) and congestive heart failure (75% vs. 0%, P = 0.0001) in comparison with those with in situ thrombosis. Neurologic deficit was present in 16 (55%) patients. Six patients (21%) presented with bilateral paresis/paralysis secondary to spinal cord or lumbosacral plexus ischemia, and primary neurologic etiology was investigated before vascular consultation was obtained in 4 of these 6 patients. Of the 29 patients, 28 (97%) underwent revascularization including transfemoral embolectomy (n = 6), transperitoneal aortoiliac thrombectomy (n = 2), axillobifemoral bypass (n = 10), aortobifemoral bypass (n = 6), and endovascular therapy including thrombolysis, angioplasty ± stenting (n = 4). In-hospital mortality was 31% and did not vary significantly according to etiology (embolism 38% vs. in situ thrombosis 29%, P = 0.67). In-hospital mortality varied widely according to procedure (transfemoral embolectomy 50%, aortoiliac thrombectomy 100%, axillobifemoral bypass 30%, aortobifemoral bypass 0%, and endovascular therapy 25%, P = 0.08). Major morbidity (59%), length of stay (8.6 ± 8.0 days), and discharge to a rehabilitation facility (50%) did not vary by etiology or procedure. At a media follow-up of 361 ± 460 days (range 3-2014), overall survival was 42%. There were no amputations among 20 survivors of initial hospitalization. CONCLUSIONS: AAO is now more commonly caused by in situ thrombosis rather than embolism. A high index of suspicion for AAO is required for prompt diagnosis and treatment, particularly when patients present with profound lower extremity neurologic deficit. In comparison with previous reports, the contemporary management of AAO includes increased use of axillobifemoral bypass and now involves endovascular revascularization, although a variety of open surgical procedures are utilized. However, the in-hospital mortality and morbidity of AAO has not decreased significantly over the last 2 decades and mid-term survival remains limited. Further study is required to identify strategies that improve outcomes after AAO.

Risk Factors for Long-Term Mortality and Amputation after Open and Endovascular Treatment of Acute Limb Ischemia.

BACKGROUND: Acute limb ischemia (ALI) is a highly morbid and fatal vascular emergency with little known about contemporary, long-term patient outcomes. The goal was to determine predictors of long-term mortality and amputation after open and endovascular treatment of ALI. METHODS: A retrospective review of ALI patients at a single institution from 2005 to 2011 was performed to determine the impact of revascularization technique on 5-year mortality and amputation. For each main outcome 2 multivariable models were developed; the first adjusted for preoperative clinical presentation and procedure type, the second also adjusted for postoperative adverse events (AEs). RESULTS: A total of 445 limbs in 411 patients were treated for ALI. Interventions included surgical thrombectomy (48%), emergent bypass (18%), and endovascular revascularization (34%). Mean age was 68 ± 15 years, 54% were male, and 23% had cancer. Most patients presented with Rutherford classification IIa (54%) or IIb (39%). The etiology of ALI included embolism (27%), in situ thrombosis (28%), thrombosed bypass grafts (32%), and thrombosed stents (13%). Patients treated with open procedures had significantly more advanced ischemia and higher rates of postoperative respiratory failure, whereas patients undergoing endovascular interventions had higher rates of technical failure. Rates of postprocedural bleeding and cardiac events were similar between both treatments. Excluding Rutherford class III patients (n = 12), overall 5-year mortality was 54% (stratified by treatment, 65% for thrombectomy, 63% for bypass, and 36% for endovascular, P < 0.001); 5-year amputation was 28% (stratified by treatment, 18% for thrombectomy, 27% for bypass, and 17% for endovascular, P = 0.042). Adjusting for comorbidities, patient presentation, AEs, and treatment method, the risk of mortality increased with age (hazard ratio [HR] = 1.04, P < 0.001), female gender (HR = 1.50, P = 0.031), cancer (HR = 2.19, P < 0.001), fasciotomy (HR = 1.69, P = 0.204) in situ thrombosis or embolic etiology (HR = 1.73, P = 0.007), cardiac AEs (HR = 2.25, P < 0.001), respiratory failure (HR = 2.72, P < 0.001), renal failure (HR = 4.70, P < 0.001), and hemorrhagic events (HR = 2.25, P = 0.003). Risk of amputation increased with advanced ischemia (Rutherford IIb compared with IIa, HR = 2.57, P < 0.001), thrombosed bypass etiology (HR = 3.53, P = 0.002), open revascularization (OR; HR = 1.95, P = 0.022), and technical failure of primary intervention (HR = 6.01, P < 0.001). CONCLUSIONS: After the treatment of ALI, long-term mortality and amputation rates were greater in patients treated with open techniques; OR patients presented with a higher number of comorbidities and advanced ischemia, while also experiencing a higher rate of major postoperative complications. Overall, mortality rates remained high and were most strongly associated with baseline comorbidities, acuity of presentation, and perioperative AEs, particularly respiratory failure. Comparatively, amputation risk was most highly associated with advanced ischemia, thrombosed bypass, and failure of the initial revascularization procedure.

Bio-absorbable antibiotic impregnated beads for the treatment of prosthetic vascular graft infections.

OBJECTIVE: There is limited investigation into the use of bio-absorbable antibiotic beads for the treatment of prosthetic vascular graft infections. Our goal was to investigate the rates of infection eradication, graft preservation, and limb salvage in patients who are not candidates for graft explant or extensive reconstruction. METHODS: A retrospective review of patients implanted with antibiotic impregnated bio-absorbable calcium sulfate beads at a major university center was conducted. RESULTS: Six patients with prosthetic graft infections were treated with bio-absorbable antibiotics beads from 2012-2014. Grafts included an aortobifemoral, an aorto-hepatic/superior mesenteric artery, and four extra-anatomic bypasses. Pathogens included Gram-positive and Gram-negative bacteria. Half of the patients underwent graft explant with reconstruction and half debridement of the original graft, all with antibiotic bead placement around the graft. Mean follow-up was 7.3 ± 8.3 months; all patients had infection resolution, healed wounds, and 100% graft patency, limb salvage, and survival. CONCLUSION: This report details the successful use of bio-absorbable antibiotic beads for the treatment prosthetic vascular graft infections in patients at high risk for graft explant or major vascular reconstruction. At early follow-up, we demonstrate successful infection suppression, graft preservation, and limb salvage with the use of these beads in a subset of vascular patients.

The increased use of computed tomography angiography and magnetic resonance angiography as the sole imaging modalities prior to infrainguinal bypass has had no effect on outcomes.

BACKGROUND: Angiography remains the gold standard imaging modality before infrainguinal bypass. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have emerged as noninvasive alternatives for preoperative imaging. We sought to examine contemporary trends in the utilization of CTA and MRA as isolated imaging modalities before infrainguinal bypass and to compare outcomes following infrainguinal bypass in patients who underwent CTA or MRA versus those who underwent conventional arteriography. METHODS: Patients undergoing infrainguinal bypass within the Vascular Study Group of New England were identified (2003-2012). Patients were stratified by preoperative imaging modality: CTA/MRA alone or conventional angiography. Trends in utilization of these modalities were examined and demographics of these groups were compared. Primary end points included primary patency, secondary patency, and major adverse limb events (MALE) at 1 year as determined by Kaplan-Meier analysis. Multivariable Cox proportional hazards models were constructed to evaluate the effect of imaging modality on primary patency, secondary patency, and MALE after adjusting for confounders. RESULTS: In 3123 infrainguinal bypasses, CTA/MRA alone was used in 462 cases (15%) and angiography was used in 2661 cases (85%). Use of CTA/MRA alone increased over time, with 52 (11%) bypasses performed between 2003 and 2005, 189 (41%) bypasses performed between 2006 and 2009, and 221 (48%) bypasses performed between 2010 and 2012 (P < 0.001). Patients with CTA/MRA alone, compared with patients with angiography, more frequently underwent bypass for claudication (33% vs. 26%, P = 0.001) or acute limb ischemia (13% vs. 5%, P < 0.0001), more frequently had prosthetic conduits (39% vs. 30%, P = 0.001), and less frequently had tibial/pedal targets (32% vs. 40%, P = 0.002). After adjusting for these and other confounders, multivariable analysis demonstrated that the use of CTA/MRA alone was not associated with a significant difference in 1 year primary patency (hazard ratio [HR] 0.95, 95% confidence interval [CI] 0.78-1.16), secondary patency (HR 1.30, 95% CI 0.99-1.72), or MALE (HR 1.08, 95% CI 0.89-1.32). CONCLUSIONS: CTA and MRA are being increasingly used as the sole preoperative imaging modality before infrainguinal bypass. This shift in practice patterns appears to have no measurable effect on outcomes at 1 year.

Trends in the incidence, treatment, and outcomes of acute lower extremity ischemia in the United States Medicare population.

OBJECTIVE: Acute lower extremity ischemia (ALI) is a common vascular surgery emergency associated with high rates of morbidity and mortality. The purpose of this study was to assess contemporary trends in the incidence of ALI, the methods of treatment, and the associated mortality and amputation rates in the U.S. Medicare population. METHODS: This was an observational study using Medicare claims data between 1998 and 2009. Outcomes examined included trends in the incidence of ALI; trends in interventions for ALI; and trends in amputation, mortality, and amputation-free survival rates. RESULTS: Between 1998 and 2009, the incidence of hospitalization for ALI decreased from 45.7 per 100,000 to 26.0 per 100,000 (P for trend < .001). The percentage of patients undergoing surgical intervention decreased from 57.1% to 51.6% (P for trend < .001), whereas the percentage of patients undergoing endovascular interventions increased from 15.0% to 33.1% (P for trend < .001). In-hospital mortality rates decreased from 12.0% to 9.0% (P for trend < .001), whereas 1-year mortality rates remained stable at 41.0% and 42.5% (P for trend not significant). In-hospital amputation rates remained stable at 8.1% and 6.4% (P for trend not significant), whereas 1-year amputation rates decreased from 14.8% to 11.0% (P for trend < .001). In-hospital amputation-free survival after hospitalization for ALI increased from 81.2% to 85.4% (P for trend < .001); however, 1-year amputation-free survival remained unchanged. CONCLUSIONS: Between 1998 and 2009, the incidence of ALI among the U.S. Medicare population declined significantly, and the percentage of patients treated with endovascular techniques markedly increased. During this time, 1-year amputation rates declined. Furthermore, although in-hospital mortality rates declined after presentation with ALI, 1-year mortality rates remained unchanged.