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.

Interwoven nitinol stents for the treatment of infrainguinal peripheral arterial disease.

Endovascular treatment of peripheral arterial disease has emerged as a minimally-invasive alternative to surgical intervention and has often become the first-line therapy. The patency of these interventions has shown promise but has remained variable depending upon the location, length of lesion and device used for a particular treatment. Specifically, one of the most common locations that is treated with endovascular means for chronic-limb threatening ischemia is the femoropopliteal region. This area of the arterial tree is highly exposed to movements such as flexion, extension, and rotational torque; as such, placing metallic stents can result in kinking and damage to the stent, and subsequently the artery, over time. Stent characteristics are defined according to the metal property that composes them. Nitinol has been experimented with for use in the arterial tree since the 1980s namely because of its uniquely elastic mechanical properties, which were ideal for sustaining its shape within an anatomic area prone to positional variability. More recently, nitinol stents were introduced in an interwoven fashion, the design of which creates a scaffold of structure for the elastic property of the metal to remain reinforced within highly flexible arteries. This review article discusses the available literature and evidence behind the use of these interwoven nitinol stents in lower extremity peripheral arterial interventions.

Arterial spin labeling magnetic resonance imaging quantifies tissue perfusion around foot ulcers.

Objective: Tools that quantify tissue perfusion of the foot are deficient, contributing to the uncertainty in predicting ulcer healing potential. This pilot study aims to quantify peri-wound foot perfusion at various tissue depths using a novel application of pseudo-continuous arterial spin labeling magnetic resonance imaging. Methods: Ten diabetic patients with neuropathic wounds and 20 healthy volunteers without wounds were recruited. Wounds were graded according to the Wound, Ischemia, Foot Infection (WIfI) system. All subjects underwent a noncontrasted ASL MRI of the foot for perfusion measurements. For healthy volunteers, perfusion was compared at rest and during sustained toe flexion between four regions: lateral plantar, medial plantar, lateral calcaneal, and medial calcaneal. Evaluations of diabetic volunteers compared perfusion between four zones: wound, near border, far border, and remote. Remote zone perfusion in diabetics was compared with perfusion in the plantar foot of healthy volunteers. Results: There were 11 wounds, which were located over the metatarsal heads in five, the stump of a transmetatarsal amputation in three, the heel in two, and the mid foot in one. The median WIfI stage was 2. One patient had a WIfI ischemia grade of 1; the remaining patients' grades were 0. The mean ankle-brachial index was 1.0 ± 0.3. There were two patients with a WIfI foot infection grade of 1; the remaining patients' grades were 0. In healthy volunteers, plantar foot perfusion with sustained toe flexion was 43.9 ± 1.7 mL/100g/min and significantly higher than perfusion at rest (27.3 ± 2.7 mL/100g/min; P < .001). In diabetic patients, perfusion at the wound, near border, far border, and remote regions was 96.1 ± 10.7, 92.7 ± 9.4, 73.4 ± 8.2, and 62.8 ± 2.7 mL/100g/min. Although this perfusion pattern persisted throughout the depth of the wound, perfusion decreased with tissue depth. In the near border, perfusion at 20% of the wound depth was 124.0 ± 35.6 mL/100g/min and 69.9 ± 10.1 mL/100g/min at 100% (P = .006). Lastly, remote perfusion in diabetics was 2.3 times the plantar perfusion in healthy volunteers (27.3 ± 2.7 mL/100g/min; P < .001). Conclusions: The pattern of resting tissue perfusion around nonischemic diabetic foot ulcers was successfully quantified with arterial spin labeling magnetic resonance imaging. Diabetic patients with wounds were hyperemic compared with healthy volunteers. There was a 1.5-fold increase in peri-wound tissue perfusion relative to the rest of the foot. This study is the first step in developing a tool to assess the perfusion deficit in ischemic wounds.

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.

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.

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.

Adjunctive techniques to minimize thrombotic complications following microfoam sclerotherapy of saphenous trunks and tributaries.

OBJECTIVE: Thrombus extension into the deep venous system following superficial vein chemical ablation with Varithena polidocanol microfoam has been reported. The objective of this study was to assess the effect of intraoperative improved techniques during treatment for patients with symptomatic varicose veins and their impact on extension of thrombus into deep veins. METHODS: A retrospective review of a prospectively maintained database was performed. All patients who underwent endovenous chemical ablation with polidocanol microfoam (Varithena, Boston Scientific, Marlborough, Mass) for symptomatic superficial axial and tributary vein reflux were identified. Patients had postoperative duplex (48-72 hours) scanning after the procedure; those who did not adhere to the recommended follow-up were excluded. Demographic data, CEAP Classification, Venous Clinical Severity Score, procedure details, and follow-up data were abstracted. RESULTS: Between April 2018 and August 2020, 157 limbs in 122 patients were treated with Varithena microfoam; 129 limbs in 99 patients met our inclusion criteria. Veins treated included the great saphenous vein (n = 89), anterior accessory saphenous vein (n = 15), small saphenous vein (n = 14), and tributary veins (n = 56). Adjunctive techniques during treatment included intraoperative elevation of the limb to greater than 45°, ultrasound mapping and digital occlusion of large perforator veins, limitation of foam volume per session, injection of sterile saline before treatment, and compression of the limb in the elevated position. The preoperative Venous Clinical Severity Score was 11.4 and decreased after treatment to 9.7. The immediate closure rate was 95% with 81% overall symptomatic relief at last follow-up. The mean follow-up was 113.5 days for the entire cohort; two limbs (1.5%) required postoperative anticoagulation for thrombus extension into the deep venous system (common femoral vein n = 1; popliteal vein n = 1) postoperatively for a mean of 22 days. Both resolved with anticoagulation. One asymptomatic limb developed a femoral vein deep venous thrombosis and one symptomatic late deep venous thrombosis was noted 4 months after the procedure. Postoperative pain and phlebitis were reported in 15.6% and 14.8% of patients, respectively, and all had resolved at last follow-up. No pulmonary emboli were noted and no neurologic or visual adverse events were recorded. CONCLUSIONS: Adjunctive techniques during microfoam ablation decreased thrombotic complications in our series compared with those reported in earlier phase III clinical trials. Excellent early closure and symptomatic improvement were also noted. Endovenous microfoam ablation with Varithena is a safe and effective nontumescent, nonthermal alternative to laser and radiofrequency ablation.

Aortoesophageal fistula treated with staged aortic stent graft and subsequent homograft interposition.

Aortoesophageal fistula (AEF) is a rare complication of esophageal interventions. We present a 49-year-old woman who underwent Roux-en-Y gastric bypass with a recurrent gastrojejunal anastomotic leak requiring covered esophageal stent placement. She presented 1 month later with abdominal pain, leukocytosis, and hematemesis. A computed tomography scan demonstrated migration of the esophageal stent with aortic erosion concerning for AEF. She underwent emergent endovascular exclusion of an AEF to the descending thoracic aorta with subsequent esophageal resection and diversion and aortic endograft explant, resection, and homograft repair on postoperative day 6 allowing for staged removal of prosthetic material and maintenance of inline flow.

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.

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.

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.

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.

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.