Influence of baseline kidney dysfunction on perioperative renal outcomes after endovascular aneurysm repair with suprarenal fixation.

BACKGROUND: Conflicting evidence exists regarding the comparative effects of endovascular aneurysm repair (EVAR) with and without suprarenal fixation. We compare outcomes in patients treated by EVAR with baseline normal kidney function and moderate and severe chronic kidney disease. METHODS: Patients with normal kidney function (glomerular filtration rate [GFR] ≥60 mL/min/1.73 m2) or moderate (GFR = 30-59 mL/min/1.73 m2) or severe (GFR <30 mL/min/1.73 m2) kidney disease who underwent EVAR (N = 5534) were identified from the American College of Surgeons National Surgical Quality Improvement Program targeted database (2011-2015). Groups were determined by the presence (Cook Zenith [Cook Medical, Bloomington, Ind] or Medtronic Endurant [Medtronic, Minneapolis, Minn]) or absence (Gore Excluder [W. L. Gore & Associates, Flagstaff, Ariz]) of a suprarenal fixation system. Postoperative renal complications, defined as rise in creatinine concentration of >2 mg/dL without dialysis or new dialysis requirements, were analyzed within the first 30 days with results stratified by degree of kidney disease. RESULTS: A total of 5534 patients underwent EVAR, with 3225 (58.3%) receiving a device using a suprarenal fixation system. Suprarenal fixation systems were less commonly used for symptomatic patients (11.0% vs 13.7%; P = .002) and patients with ruptured abdominal aortic aneurysm (4.5% vs 6.3%; P = .01). There was no difference in baseline kidney function between groups. EVAR with suprarenal fixation was associated with more renal complications (1.40% vs 0.65%; P = .008). In subgroup analysis, patients with moderate kidney dysfunction (n = 1780) had more renal complications (2.2% vs 0.8%; P = .02) with suprarenal fixation systems. No differences were seen in patients with normal kidney function (0.4% vs 0.2%; P = .32; n = 3597) or severe kidney dysfunction (14.3% vs 10.2%; P = .45; n = 157). This difference was driven mostly by postoperative elevation of creatinine concentration (0.6% vs 0.2%; P = .03) without requirements for new dialysis (0.8% vs 0.4%; P = .08). After adjustments with multivariate logistic regression models, EVAR with suprarenal fixation was associated with more renal complications (odds ratio, 2.65; 95% confidence interval, 1.32-5.34). CONCLUSIONS: In our study, EVAR with suprarenal fixation devices was associated with more perioperative renal complications in patients with moderate kidney dysfunction. Long-term evaluation of these patients undergoing EVAR should be considered.

Economic burden and clinical impact of preoperative opioid dependence for patients undergoing lower extremity bypass surgery.

OBJECTIVE: Surgeons' prescription practices and the opioid epidemic have received significant attention in the media. Limited data exist, however, on the impact of prior or coexistent opioid use on vascular surgery outcomes. This study aimed to quantify the incidence, economic burden, and clinical impact of pre-existing opioid dependency in patients undergoing lower extremity bypass (LEB) surgery. METHODS: Data were collected from 1,132,645 weighted (230,858 unweighted) patient admissions for LEB in the National Inpatient Sample for the years 2002 to 2015. Patients with a concomitant diagnosis of opioid abuse or dependency were identified using International Classification of Diseases, Ninth Revision codes. Matched cohorts of patients with (n = 606 unweighted) and without (n = 32,343 unweighted) opioid dependence were created using coarsened exact matching to control for patient demographics. Linear regression was used to control for hospital-level factors and to identify differential outcomes for patients with opioid dependency. Our primary end points were hospital cost and length of stay. Our secondary end points were surgical complications and in-hospital mortality. RESULTS: There were 1,132,645 (230,858 unweighted) patient admissions for LEB in the National Inpatient Sample during 2002 to 2015. There were 3190 (0.3%) patients (643 unweighted) who had a diagnosis of pre-existing opioid dependency. The incidence of opioid dependency rose over time (2002, 0.13%; 2015, 0.63%; R2 = 0.90; P < .001). Before matching, opioid-dependent patients were younger (53.9 ± 12.3 years vs 66.7 ± 12.1 years; P < .001) and more likely to be male (65.2% vs 61.9%; P < .001), to be nonwhite (37.9% vs 24.1%; P < .001), to pay with Medicaid (29.6% vs 7.4%; P < .001), and to fall in the lowest income quartile based on ZIP code (39.6% vs 27.5%; P < .001). After matching, opioid-dependent patients (n = 606 unweighted vs n = 32,343 unweighted nonopioid-dependent patients) were at increased risk of surgical site infections (odds ratio [OR], 1.61; P = .006), major bleeding (OR, 1.56; P = .04), acute kidney injury (OR, 1.46; P = .02), and deep venous thrombosis (OR, 2.53; P = .005). Linear regression of matched cohorts revealed that opioid-dependent patients had an increased length of hospital stay (11.76 days vs 9.80 days; P < .001) and an increased mean inflation-adjusted in-hospital cost of U.S. $7032 ($37,522 vs $30,490; P < .001). CONCLUSIONS: The incidence of pre-existing opioid dependency in patients undergoing LEB continues to rise. Patients with opioid use disorder undergoing LEB surgery have substantial increases in length of hospital stay and costs. These findings highlight the importance of early preoperative recognition of this disorder in vascular surgery patients and open the opportunity for early intervention in that cohort.

Unenhanced Velocity-Selective MR Angiography (VS-MRA): Initial Clinical Evaluation in Patients With Peripheral Artery Disease.

BACKGROUND: Safe and accurate imaging of the peripheral arterial system is important for diagnosis and treatment planning of patients with peripheral artery disease (PAD). PURPOSE: To evaluate image quality and diagnostic performance of unenhanced magnetic resonance angiography (MRA) based on velocity-selective (VS) magnetization preparation (termed VS-MRA). STUDY TYPE: Prospective. POPULATION: Thirty-one symptomatic PAD patients underwent VS-MRA. Twenty-four of them underwent clinical digital subtraction angiography (DSA) examination, 18.8 ± 5.2 days after the MR scans. FIELD STRENGTH/SEQUENCE: 1.5T MRI that included VS-MRA (homemade research sequence) and phase-contrast flow imaging (clinical sequence). ASSESSMENT: Image quality (0: nondiagnostic, 3: excellent) and stenosis severity (0: normal, 3: occlusion) of VS-MRA images were assessed independently by three reviewers. Arterial signal-to-noise-ratio (SNR) and artery-to-muscle contrast-to-noise ratio (CNR) were calculated. STATISTICAL TESTS: The sensitivity and specificity of VS-MRA were calculated for the detection of significant stenosis (>50%) with DSA as the reference standard. Interobserver agreement among the three reviewers was evaluated by using Cohen κ-statistics. RESULTS: The image quality score of VS-MRA was 2.7 ± 0.5 for Reader 1, 2.8 ± 0.5 for Reader 2, and 2.8 ± 0.4 for Reader 3; SNR and CNR were 37.8 ± 12.5 and 30.5 ± 11.8, respectively. Segment-based analysis revealed that VS-MRA had sensitivities of 85.3%, 74.5%, and 78.4%, respectively, for the three reviewers, and specificities of 93.5%, 96.8%, and 95.2%. The interobserver agreement for the stenosis grading was good, as demonstrated by Cohen κ values of 0.76 (Reader 1 vs. Reader 2), 0.82 (Reader 1 vs. Reader 3), and 0.79 (Reader 2 vs. Reader 3). DATA CONCLUSION: Unenhanced VS-MRA allows clear depiction of the peripheral arteries and accurate stenosis grading, as evidenced by high image quality scores and strong agreement with DSA. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:744-751.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Not Yet Applicable for Widespread Out-of-Hospital Use: A Case of Nonsurvivable Complication from Prolonged REBOA Inflation.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is being considered for temporizing catastrophic hemorrhage before arriving at a specialty center for definitive surgical management. CASE: We describe the clinical case of a 72-year-old male with a ruptured infrarenal aortic abdominal aneurysm initially stabilized with REBOA at an outside facility and transferred to our care. Transport time was >100 minutes. Despite successful surgical repair of the ruptured aneurysm, the patient expired from multiple-organ failure likely related to ischemia-reperfusion injuries from prolonged balloon occlusion of the aorta. CONCLUSIONS: Ischemia-mitigating techniques and therapies need to improve drastically before the clinical application of REBOA can be effectively extended to outside the vicinity of specialty centers.

Motorized scooter injuries in the era of scooter-shares: A review of the national electronic surveillance system.

INTRODUCTION: There has been a spike in recent news regarding motorized scooter injuries due to the expansion of scooter sharing companies. Given the paucity of literature on this topic, the purpose of our study was to describe and quantify emergency department encounters associated with motorized scooter related injuries. METHODS: The National Electronic Injury Surveillance System (NEISS) was queried for motorized scooter related injuries from 2013 to 2017. Patient demographics, diagnosis, injury location, narrative description of incident, and disposition data were collected from emergency department encounters. RESULTS: There were an estimated 32,400 motorized scooter injuries from 2013 to 2017. The estimated incidence did not change significantly over time with 1.9 cases per 100,000 in 2013 and 2.6 cases per 100,000 in 2017. A 77.0% increase in scooter injuries was noted for millennials from 2016 to 2017. Head injuries were the most common body area injured (27.6%). Fractures or dislocations (25.9%) were the most common diagnosis. The most common site of fracture was the wrist and lower arm (35.4%). There were no deaths. Major orthopaedic injury and concussion were the strongest independent predictors of hospital admission. CONCLUSIONS: Head injuries were the most commonly injured body part, while fractures or dislocations were the most common diagnosis. These results highlight the importance of using protective equipment while riding motorized scooters, and lay a foundation for future policies requiring helmet use.

Continuous Flow Perfused Cadaver Model for Endovascular Training, Research, and Development.

BACKGROUND: Endovascular simulation employing computer, animal, and static models are common and useful adjuncts for teaching endovascular procedures and developing novel, complex endovascular techniques. Unfortunately, these models lack realistic haptic feedback and thus do not faithfully replicate many of the technical challenges associated with clinical endovascular procedures (e.g., arterial calcification, rigidity, and stenosis). We sought to develop a realistic and reproducible perfused cadaver model for endovascular training, device development, and research. METHODS: Fresh frozen, elderly (age 50-80 years) male cadavers were thawed and prepared for open dissection. The entire arterial tree (ascending aorta to femoral arteries) was dissected free and major branch vessels exposed. Sheaths were placed to allow outflow from selected vessels. A Dacron conduit was sewn to the ascending aorta to generate arterial inflow, which was provided by a centrifugal pump. Aortic aneurysms were created in the descending thoracic and abdominal aorta. Digital subtraction arteriography and various endovascular interventions were performed, including stent grafts and EndoAnchors deployment. RESULTS: Continuous antegrade flow was achieved in the thoracic, abdominal, iliac, and femoral segments. Open and percutaneous access at the femoral region was obtained with realistic back-bleeding and tactile feedback. Adequate, fluoroscopically documented flow was observed in both cannulated major and noncannulated smaller branches. We performed angiography with standard techniques via a pigtail catheter and contrast injector throughout the arterial system. Abdominal and thoracic endografts were deployed with appropriate angiographic guidance and realistic haptic feedback for both guidewire and stent grafts. Additional applications, including selective cannulation, aorto-iliac occlusive disease interventions, and anchor placement, were also successfully simulated. Finally, the model was used as a platform to test investigational devices. CONCLUSIONS: Our pressurized cadaver flow model successfully replicated multiple aspects of advanced endovascular procedures with haptic feedback. This novel human cadaver model allows for training and device development under clinically realistic conditions.

Flow Reduction-Aided Thrombin Injection for Complex Femoral Pseudoaneurysms: Case Series and Review of the Literature.

BACKGROUND: Peripheral pseudoaneurysms are a known complication of vascular access procedures. Complex lesions-those with short, wide necks or other complex arrangements-would conventionally require open repair, but we believe that even these lesions could be managed with an endovascular approach. METHODS: Four patients with complex pseudoaneurysms were offered an open repair or thrombin injection with the use of flow-reducing balloons. RESULTS: In our series of 4 patients with complex pseudoaneurysms, all were safely treated with percutaneous thrombin injection in conjunction with endovascular flow reduction. All patients recovered from their procedures without incident and are free from recurrence at follow-up. CONCLUSIONS: Flow reduction-aided thrombin injection may have particular utility in complex femoral pseudoaneurysms, especially in a patient population that may not tolerate open repair. High-risk lesions may merit special consideration for this technique, and further study is warranted.

Early Treatment at a Referral Center Improves Outcomes for Patients with Acute Vascular Disease.

BACKGROUND: Patients with acute vascular disease frequently need specialized management that may require transfer to a vascular referral center. Although transfer may be medically necessary, it can delay definitive care and is an indicator of incorrect triage to the initial hospital. Regionalization of acute vascular care could improve patient triage and subsequent outcomes. To evaluate the potential benefit from regionalization, we analyzed outcomes of patients treated for acute vascular disease at vascular referral centers. METHODS: Using a statewide database capturing all inpatient admissions in Maryland during 2013-2015, patients undergoing noncardiac vascular procedures on an acute basis were identified. Patients admitted to a vascular referral center were stratified by admission status as direct or transfer. The primary outcome was inpatient mortality, and the secondary outcome was resource use. Patient groups were compared by univariable analyses, and the effect of admission status on mortality was assessed by multivariable logistic regression. RESULTS: Of 4,873 patients with acute vascular disease managed at vascular referral centers, 2,713 (56%) were admitted directly, whereas 2,160 (44%) were transferred. Transfers to referral centers accounted for 71% of all interhospital transfers. The transfer-group patients were older, had more comorbidities, and higher illness severities. Patients who were transferred had higher mortality (14% vs. 9%, P < 0.0001), longer hospital lengths of stay, greater critical care-resource utilization, and higher costs. After adjusting for demographics, comorbidities, and illness severity, transfer status was independently associated with higher inpatient mortality. CONCLUSIONS: Primary treatment at a referral center is independently associated with improved outcomes for patients with acute vascular disease. Direct admission or earlier triage to a specialty center may improve patient and system outcomes and could be facilitated by standardization and regionalization of complex acute vascular care.

Management and outcomes of carotid artery extension of aortic dissections.

BACKGROUND: Aortic dissection (AD) is the most common aortic catastrophe. Carotid artery dissection due to extension of AD (CAEAD) is one severe complication of this condition. Despite years of refinement in the techniques for repair of AD, the optimal management strategy for CAEAD remains yet to be described. We hypothesized that CAEAD eventually resolves on antiplatelet therapy with a low but not insignificant risk of cerebrovascular accident (CVA). METHODS: This was a single-institution retrospective review of patients admitted with nontraumatic coincident aortic and carotid dissection between 2001 and 2013. RESULTS: CAEAD was present in 38 patients (24 men [53%]). The median age was 59.5 years (range, 25-85 years). A Stanford type A AD was diagnosed in 36 patients (95%). CVA or transient ischemic attack was identified in 11 patients (29%). Eight were potentially attributable to the carotid lesion. Two of these eight strokes resulted in death. Of the 11 CVAs and transient ischemic attacks, 8 were evident at presentation, 2 were diagnosed postoperatively during hospitalization, and 1 was diagnosed during early follow-up. Only one of these three postadmission strokes was attributable to the carotid lesion. Nonoperative management of aortic and carotid dissections was pursued in 9 patients (24%), 26 (68%) underwent open repair, and 4 (11%) had endovascular management of AD (2 thoracic endovascular aortic repair, 2 endovascular fenestrations), including 1 patient with a staged hybrid procedure (frozen elephant trunk). There were eight inpatient deaths (21%) and nine deaths in the follow-up period. Of the 30 patients who survived to discharge, 24 (80%) were managed with antiplatelet therapy. At a median follow-up of 14.5 months in 22 patients with follow-up computed tomography scans available, a minority of lesions had resolved, and only one CVA was reported. CONCLUSIONS: This study found that CAEAD was associated almost exclusively with type A AD, was typically unilateral, most often on the left, and usually persisted at follow-up. Many CAEAD patients presented with CVA and experienced significant early mortality. Notably, not all CVA events were attributable to the CAEAD. CVAs were not common after admission, and there appeared to be a low risk of new or subsequent stroke during follow-up with routine antiplatelet and antihypertensive therapy.

Functional status predicts major complications and death after endovascular repair of abdominal aortic aneurysms.

OBJECTIVE: Endovascular aneurysm repair (EVAR) is considered a lower risk option for treating abdominal aortic aneurysms and is of particular utility in patients with poor functional status who may be poor candidates for open repair. However, the specific contribution of preoperative functional status to EVAR outcomes remains poorly defined. We hypothesized that impaired functional status, based simply on the ability of patients to perform activities of daily living, is associated with worse outcomes after EVAR. METHODS: Patients undergoing nonemergent EVAR for abdominal aortic aneurysm between 2010 and 2014 were identified in the National Surgical Quality Improvement Program (NSQIP) database. The primary outcomes were 30-day mortality and major operative and systemic complications. Secondary outcomes were inpatient length of stay, need for reoperation, and discharge disposition. Using the NSQIP-defined preoperative functional status, patients were stratified as independent or dependent (either partial or totally dependent) and compared by univariate and multivariable analyses. RESULTS: Of 13,432 patients undergoing EVAR between 2010 and 2014, 13,043 were independent (97%) and 389 were dependent (3%) before surgery. Dependent patients were older and more frequently minorities; had higher rates of chronic pulmonary, heart, and kidney disease; and were more likely to have an American Society of Anesthesiologists score of 4 or 5. On multivariable analysis, preoperative dependent status was an independent risk factor for operative complications (odds ratio [OR], 3.1; 95% confidence interval [CI], 2.5-3.9), systemic complications (OR, 2.8; 95% CI, 2.0-3.9), and 30-day mortality (OR, 3.4; 95% CI, 2.1-5.6). Secondary outcomes were worse among dependent patients. CONCLUSIONS: Although EVAR is a minimally invasive procedure with substantially less physiologic stress than in open aortic repair, preoperative functional status is a critical determinant of adverse outcomes after EVAR in spite of the minimally invasive nature of the procedure. Functional status, as measured by performance of activities of daily living, can be used as a valuable marker of increased perioperative risk and may identify patients who may benefit from preoperative conditioning and specialized perioperative care.

Defining the burden, scope, and future of vascular acute care surgery.

OBJECTIVE: The paradigm of acute care surgery has revolutionized nonelective general surgery. Similarly, nonelective vascular surgery may benefit from specific management and resource capabilities. To establish the burden and scope of vascular acute care surgery, we analyzed the characteristics and outcomes of patients hospitalized for vascular surgical procedures in Maryland. METHODS: A retrospective analysis of a statewide inpatient database was performed to identify patients undergoing noncardiac vascular procedures in Maryland from 2009 to 2013. Patients were stratified by admission acuity as elective, urgent, or emergent, with the last two groups defined as acute. The primary outcome was inpatient mortality, and secondary outcomes were critical care and hospital resource requirements. Groups were compared by univariate analyses, with multivariable analysis of mortality based on acuity level and other potential risk factors for death. RESULTS: Of 3,157,499 adult hospital admissions, 154,004 (5%) patients underwent a vascular procedure; most were acute (54% emergent, 13% urgent), whereas 33% were elective. Acute patients had higher rates of critical care morbidity and required more hospital resource utilization. Admission for acute vascular surgery was independently associated with mortality (urgent odds ratio, 2.1; emergent odds ratio, 3.0). CONCLUSIONS: The majority of inpatient vascular care in Maryland is for acute vascular surgery, which is an independent risk factor for mortality. Acute vascular surgical care entails greater critical care and hospital resource utilization and-similar to emergency general surgery-may benefit from dedicated training and practice models.

Percutaneous Treatment of Multiple Recurrent Thromboembolization from a Descending Thoracic Aortic Intimal Sarcoma.

Aortic intimal sarcomas are rare tumors that may result in distal embolic ischemia. Here, we present a patient who presented with crescendo lower extremity and mesenteric ischemic events from malignant macroembolism. Management with percutaneous pharmacomechanical thromboembolectomy enabled restoration of distal perfusion and minimally invasive collection of tumor sample to confirm the suspected diagnosis of aortic sarcoma. The patient underwent definitive aortectomy and reconstruction and is recovering well.

Thoracic Endovascular Repair of Blunt Thoracic Aortic Injury in the Setting of an Aberrant Right Subclavian Artery.

Blunt thoracic aortic injury (BTAI) in a patient with an aberrant right subclavian artery (ARSA) presents unique challenges for patient management and aortic repair. Specific considerations include the need to treat coincidental ARSA, subclavian revascularization, and ARSA exclusion. Despite the rise of endovascular repair as the primary modality for aortic repair for BTAI, reports of this technique in the setting of ARSA are limited. Here we describe 3 patients with ARSA who underwent TEVAR for BTAI, and discuss critical management and technical issues in these patients.

Identification and reduction of image artifacts in non-contrast-enhanced velocity-selective peripheral angiography at 3T.

PURPOSE: To identify and reduce image artifacts in non-contrast-enhanced velocity-selective (VS) magnetization-prepared peripheral MR angiography (MRA) at 3T. METHODS: To avoid signal loss in the arteries, double and quadruple refocused VS excitation pulse sequences were designed that were robust to a wide range of B0 and B1 offset. To suppress stripe artifact and background signal variation, we successively applied two VS preparations with excitation profiles shifted by half the period of the stripes. VS-MRA using single, double, and quadruple refocused VS preparations was tested in healthy subjects and a patient. RESULTS: In the regions of large B0 and B1 offsets, arterial signal loss was yielded by single refocused VS preparation, but was avoided with double or quadruple refocused preparations. Compared with single VS preparation, the two consecutive preparations with shifted excitation profiles substantially reduced the stripe artifact and background signal variation, as demonstrated by increased mean and decreased standard deviation of relative contrast-to-noise ratio. The proposed VS-MRA identified multilevel disease in the femoral arteries of the patient, as validated by digital subtraction angiography. CONCLUSION: Two multiple refocused VS magnetization preparations with shifted excitation profiles yield artifact-free peripheral angiograms at 3T. Magn Reson Med 76:466-477, 2016. © 2015 Wiley Periodicals, Inc.

Noncontrast-enhanced peripheral venography using velocity-selective magnetization preparation and transient balanced SSFP.

PURPOSE: To develop a three-dimensional (3D) noncontrast-enhanced (NCE) peripheral magnetic resonance venography (MRV) method and demonstrate its feasibility in vivo. METHODS: The proposed MRV pulse sequence consisted of a velocity-selective (VS) inversion preparation module, inversion delay time (TI), fat inversion pulse, and 3D balanced steady-state free precession (bSSFP) dummy excitations and readout. The VS preparation module inverted arterial blood, which recovered close to zero magnetization during TI. The TI and the number of dummy excitations (Nnum ) were numerically optimized for maximizing vein-to-background contrast and tested in a healthy subject. The proposed MRV of the entire peripheral system, using four-station acquisition, was performed in six healthy subjects and three peripheral artery patients. RESULTS: The numerical optimization yielded TI = 350 ms and Ndum = 40, which was supported by the largest vein contrast among the parameters chosen around the optima on in vivo venograms. Four-station peripheral MRV using the optimized parameters well visualized all major deep veins with high vein-to-background contrast. The relative vein contrast ratios were 0.80 ± 0.08, 0.75 ± 0.07, and 0.84 ± 0.06 against the arteries, muscle, and fat, respectively. CONCLUSION: The proposed NCE MRV using VS preparation and transient bSSFP can generate high-contrast peripheral venograms directly with a single acquisition.

Ethyl pyruvate modulates delayed paralysis following thoracic aortic ischemia reperfusion in mice.

OBJECTIVE: Delayed paralysis is an unpredictable problem for patients undergoing complex repair of the thoracic/thoracoabdominal aorta. These experiments were designed to determine whether ethyl pyruvate (EP), a potent anti-inflammatory and antioxidant agent, might ameliorate delayed paralysis following thoracic aortic ischemia reperfusion (TAR). METHODS: C57BL6 mice were subjected to 5 minutes of thoracic aortic ischemia followed by reperfusion for up to 48 hours. Mice received either 300 mg/kg EP or lactated ringers (LR) at 30 minutes before ischemia and 3 hours after reperfusion. Neurologic function was assessed using an established rodent scale. Spinal cord tissue was analyzed for markers of inflammation (keratinocyte chemoattractant [KC], interleukin-6 [IL-6]), microglial activation (ionized calcium-binding adapter molecule-1 [Iba-1]), and apoptosis (Bcl-2, Bax, and terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL] staining) at 24 and 48 hours after TAR. Nissl body stained motor neurons were counted in the anterior horns sections from L1-L5 segments. RESULTS: Ninety-three percent of the LR mice developed dense delayed paralysis between 40 and 48 hours after TAR, whereas only 39% of EP mice developed delayed paralysis (P < .01). Bcl-2 expression was higher (P < .05) and Iba-1 expression was lower (P < .05) in the EP group only at 24 hours reperfusion. At 48 hours, the number of motor neurons was higher (P < .01) and the number and TUNEL-positive cells was lower (P < .001) in the EP-treated mice. EP decreased the expression of KC (P < .01) and IL-6 (P < .001) at 48 hours after TAR. CONCLUSIONS: The protection provided by EP against delayed paralysis correlated with preservation of motor neurons, higher expression of antiapoptotic molecules, decreased microglial cell activation, and decreased spinal cord inflammation. EP may be a treatment for humans at risk for delayed paralysis.

Evolution of lesion-specific management of blunt thoracic aortic injury.

Developments in diagnosis and treatment have transformed the management of blunt thoracic aortic injuries (BTAIs). For patients in stable condition, treatment practice has shifted from early open repair to nonoperative management for low-grade lesions and routine delayed endovascular repair for more significant injuries. However, effective therapy depends on accurate staging of injury grade and stability to select patients for appropriate management. Recent developments in BTAI risk stratification enable lesion-specific management tailored to the patient and aortic lesion. This review summarizes advances in lesion assessment and treatment and proposes an integrated scheme for the modern management of BTAI.

Repair of ruptured abdominal aortic aneurysm after cardiac arrest.

OBJECTIVE: Cardiac arrest in patients with ruptured abdominal aortic aneurysm (rAAA) is not uncommon and associated with significantly increased mortality. Although it has been suggested as a contraindication to aortic repair, the prognostic implications of preoperative cardiac arrest in the face of rAAA are controversial. The purpose of this structured review is to analyze the reported outcomes of patients with rAAA and preoperative cardiac arrest. METHODS: English language single- and multi-institutional series reporting outcomes of patients with rAAA and cardiac arrest were identified by systematic literature search and review. An aggregate analysis and structured review of outcomes after subsequent aortic repair was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. The primary outcome was short-term overall mortality. RESULTS: Sixteen studies involving 2669 patients with rAAA were analyzed, including 334 (13%) with preoperative cardiac arrest. Cardiac arrest was associated with significantly increased mortality compared with patients with rAAA without arrest (86% vs 44%; P < .0001), although cardiac arrest in isolation was poorly predictive of mortality. Four patients were treated by endovascular aortic repair, and all survived. Shorter resuscitation times and return of signs of life prior to aortic repair are associated with improved survival, and long-term functional outcomes among survivors have been reported. CONCLUSIONS: Mortality among patients with rAAA and preoperative cardiac arrest is high but not prohibitive. Aortic repair should not be withheld from such patients who are otherwise reasonable candidates for intervention, provided resources for emergent aortic repair are available.

Nonoperative Management of Traumatic Aortic Pseudoaneurysms.

BACKGROUND: Current blunt thoracic aortic injury (BTAI) guidelines recommend early repair of traumatic pseudoaneurysms (PSAs) due to risk for subsequent aortic rupture. Recent analyses indicate that early repair is required only in the setting of high-risk features, while delayed repair is safe and associated with lower morbidity and mortality in appropriately selected patients. To evaluate the appropriate indications for nonoperative management (NOM) of traumatic PSAs, we performed a systematic review of studies reporting outcomes for this management strategy. We hypothesized that NOM is safe in appropriately selected patients with traumatic aortic PSAs. METHODS: English language single- and multi-institutional series reporting NOM of traumatic thoracic aortic PSAs were identified by systematic literature search and review. A descriptive analysis was performed of NOM, with stratification by lesion size and patient follow-up. The primary outcomes were late aortic intervention, aortic-related death, and all-cause mortality. RESULTS: Eighteen studies, which included 937 patients with traumatic PSAs, were analyzed. One hundred ninety-one patients were managed nonoperatively. The primary indication for NOM was prohibitive risk for aortic repair due to severe comorbidities or concurrent injuries. Where reported, PSAs with <50% circumferential involvement accounted for 88% of lesions selected for NOM. Late interventions were required in 4% of patients. Inpatient aortic-related mortality was 2%, and all-cause inpatient mortality was 32%. Although survival at up to 4-7 years was reported, postdischarge follow-up after PSA NOM was limited to <1 year in most studies. CONCLUSIONS: NOM of traumatic aortic PSAs is a common practice in BTAI series reporting lesion-specific management, and is associated with low rates of treatment failure. These findings suggest that routine early repair may not be required for traumatic PSAs, particularly for lesions limited to <50% of the aortic circumference. Definitive repair can be delayed until patient stability and repair timing can be guided by assessment of lesion stability on follow-up imaging.

A new aortic injury score predicts early rupture more accurately than clinical assessment.

OBJECTIVE: The optimal timing for repair of a high-grade blunt thoracic aortic injury (BTAI) is uncertain. Delayed repair is common and associated with improved outcomes, but some lesions may rupture during observation. To determine optimal patient selection for appropriate management, we developed a pilot clinical risk score to evaluate aortic stability and predict rupture. METHODS: Patients presenting in stable condition with Society for Vascular Surgery grade III or IV BTAI diagnosed on computed tomography (CT) were retrospectively reviewed. To determine clinical and radiographic factors associated with aortic rupture, patients progressing to aortic rupture (defined by contrast extravasation on CT or on operative or autopsy findings) were compared with those who had no intervention ≤48 hours of admission. A model targeting 100% sensitivity for rupture was generated and internally validated by bootstrap analysis. Clinical utility was tested by comparison with clinical assessment by surgeons experienced in BTAI management who were provided with CT images and clinical data but were blinded to outcome. RESULTS: The derivation cohort included 18 patients whose aorta ruptured and 31 with stable BTAI. There was no difference in age, gender, injury mechanism, nonchest injury severity, blood pressure, or Glasgow Coma Scale on admission between patient groups. As dichotomous factors, admission lactate >4 mM, posterior mediastinal hematoma >10 mm, and lesion/normal aortic diameter ratio >1.4 on the admission CT were independently associated with aortic rupture. The model had an area under the receiver operator curve of .97, and in the presence of any two factors, was 100% sensitive and 84% specific for predicting aortic rupture. No aortic lesions ruptured in patients with fewer than two factors. In contrast, clinical assessment had lower accuracy (65% vs 90% total accuracy, P < .01). CONCLUSIONS: This novel risk score can be applied on admission using clinically relevant factors that incorporate patient physiology, size of the aortic lesion, and extent of the mediastinal hematoma. The model reliably identifies and distinguishes patients with high-grade BTAI who are at risk for early rupture from those with stable lesions. Although preliminary, because it is more accurate than clinical assessment alone, the score may improve patient selection for emergency or delayed intervention.