Perioperative Cerebrospinal Fluid Drain Placement Does Not Increase Venous Thromboembolism Risk After Thoracic and Fenestrated Endovascular Aortic Repair.

BACKGROUND: Venous thromboembolism (VTE) incidence after thoracic and fenestrated endovascular aortic repair (TEVAR/FEVAR) is high (up to 6-7%) relative to other vascular procedures; however, the etiology for this discrepancy remains unknown. Notably, patients undergoing TEVAR/FEVAR commonly receive cerebrospinal fluid drains (CSFDs) for neuroprotection, requiring interruption of perioperative anticoagulation and prolonged immobility. We hypothesized that CSFDs are a risk factor for VTE after TEVAR/FEVAR. METHODS: Consecutive TEVAR/FEVAR patients at a single center were reviewed (2011-2020). Cerebrospinal fluid drains (CSFDs) were placed based on surgeon preference preoperatively or for spinal cord ischemia (SCI) rescue therapy postoperatively. The primary end-point was VTE occurrence, defined as any new deep venous thrombosis (DVT) or pulmonary embolism (PE) confirmed on imaging within 30 days postoperatively. Routine postoperative VTE screening was not performed. Patients with and without VTE, and subjects with and without CSFDs were compared. Logistic regression was used to explore associations between VTE incidence and CSFD exposure. RESULTS: Eight hundred ninety-seven patients underwent TEVAR/FEVAR and 43% (n = 387) received a CSFD at some point during their care (preoperative: 94% [n = 365/387]; postoperative SCI rescue therapy: 6% [n = 22/387]). CSFD patients were more likely to have previous aortic surgery (44% vs. 37%; P = 0.028) and received more postoperative blood products (780 vs. 405 mL; P = 0.005). The overall VTE incidence was 2.2% (n = 20). 70% (14) patients with VTE had DVT, 50% (10) had PE, and 20% (4) had DVT and PE. Among TEVAR/FEVAR patients with VTE, 65% (n = 13) were symptomatic. Most VTEs (90%, n = 18) were identified inhospital and the median time to diagnosis was 12.5 (interquartile range 7.5-18) days postoperatively. Patients with VTE were more likely to have nonelective surgery (95% vs. 41%; P < 0.001), had higher American Society of Anesthesiologists classification (4.1 vs. 3.7; P < 0.001), required longer intensive care unit admission (24 vs. 12 days; P < 0.001), and received more blood products (1,386 vs. 559 mL; P < 0.001). Venous thromboembolism (VTE) incidence was 1.8% in CSFD patients compared to 3.5% in non-CSFD patients (odds ratio 0.70 [95% confidence interval 0.28-1.78, P = 0.300). However, patients receiving CSFDs postoperatively for SCI rescue therapy had significantly greater VTE incidence (9.1% vs. 1.1%; P = 0.044). CONCLUSIONS: CSFD placement was not associated with an increased risk of VTE in patients undergoing TEVAR/FEVAR. Venous thromboembolism (VTE) risk was greater in patients undergoing nonelective surgery and those with complicated perioperative courses. Venous thromboembolism (VTE) risk was greater in patients receiving therapeutic CSFDs compared to prophylactic CSFDs, highlighting the importance of careful patient selection for prophylactic CSFD placement.

Descending thoracic aortic mural ulceration is associated with postoperative spinal cord ischemia after branched endovascular aortic aneurysm repair.

OBJECTIVE: Paraplegia is one of the most feared complications after thoracoabdominal aortic aneurysm repair. The purpose of this study is to determine whether aortic thrombus characteristics are associated with spinal cord ischemia (SCI) after branched endovascular aneurysm repair (BEVAR). METHODS: From April 2011 to April 2020, 62 patients underwent elective BEVAR for thoracoabdominal aortic aneurysm and pararenal aortic aneurysms using a low-profile device and had a complete preoperative computed tomography angiography of the aorta from the sinotubular junction to the aortic bifurcation. Aortic thrombus was evaluated for thrombus thickness ≥5 mm, thrombus >2/3 of aortic circumference, and the presence of an ulcer-like thrombus. One point was assigned at each 5 mm axial image if all 3 criteria were met, resulting in a total "shaggy score" for the entire aorta. Data on demographics, procedural details, and outcomes were collected prospectively. All patients underwent a standard spinal cord protection protocol, including routine cerebrospinal fluid drainage. In July 2016, an insulin infusion protocol (IIP) was initiated to maintain postoperative blood glucose levels <120 mg/dL for 48 hours. The primary clinical end point was postoperative SCI. RESULTS: 10 (16%) patients developed postoperative SCI: 6 with transient paraparesis, 2 with persistent paraparesis, and 2 with persistent paraplegia. Patients with SCI were older, had higher shaggy scores, and were less likely to have been on an IIP. There were no significant differences in demographics, aneurysm type, or operative parameters. In a logistic multivariate regression model for SCI, age (odds ratio [OR]: 1.2 [1.1-1.4], P = .02) and shaggy score (OR: 1.2 [1.1-1.4], P = .02) were independently associated with increased risk of SCI, whereas treatment with the IIP was associated with lower risk of SCI (OR: 0.04 [0.006-0.50], P = .05). Of the individual components of the shaggy score, higher descending thoracic aortic ulcer scores were the most strongly associated with postoperative SCI (P = .009). CONCLUSIONS: Preoperative characterization of aortic wall thrombus is an important adjunctive tool for individualized clinical decision-making and patient counseling about the risk of SCI after BEVAR.

Clinical signs, causes, and outcome of central cord syndrome in 22 cats.

OBJECTIVE: To describe the signalment, clinical findings, presumptive or definitive diagnosis, and outcome in cats with central cord syndrome (CCS). ANIMALS: 22 cats. CLINICAL PRESENTATION: Cats evaluated for CCS at 7 referral hospitals between 2017 and 2021 were included. Information retrieved from medical records included signalment, physical and neurological examination findings, diagnostic investigations, definitive or presumptive diagnosis, treatment, and follow-up. RESULTS: Median age at presentation was 9 years. Two neuroanatomical localizations were associated with CCS: C1-C5 spinal cord segments in 17 (77.3%) cats and C6-T2 spinal cord segments in 5 (22.7%) cats. Neuroanatomical localization did not correlate with lesion location on MRI in 8 (36.3%) cats. The most common lesion location within the vertebral column was over the C2 and C4 vertebral bodies in 6 (27.2%) and 5 (22.7%) cats, respectively. Peracute clinical signs were observed in 11 (50%) cats, acute in 1 (4.5%), subacute in 4 (18%), and chronic and progressive signs were seen in 6 (40.9%) cats. The most common peracute condition was ischemic myelopathy in 8 (36.3%) cats, whereas neoplasia was the most frequently identified chronic etiology occurring in 5 (22.7%) cats. Outcome was poor in 13 (59%) cats, consisting of 4 of 11 (36.6%) of the peracute cases, 3 of 4 (75%) of the subacute cases, and 6 of 6 of the chronic cases. CLINICAL RELEVANCE: Central cord syndrome can occur in cats with lesions in the C1-C5 and C6-T2 spinal cord segments. Multiple etiologies can cause CCS, most commonly, ischemic myelopathy and neoplasia. Prognosis depends on the etiology and onset of clinical signs.

Adjunctive hyperbaric oxygen therapy for spinal cord ischemia after complex aortic repair.

OBJECTIVE: Spinal cord ischemia (SCI) with paraplegia or paraparesis is a devastating complication of complex aortic repair (CAR). Treatment includes cerebrospinal fluid drainage, maintenance of hemoglobin concentration (>10 g/L), and elevating mean arterial blood pressure. Animal and human case series have reported improvements in SCI outcomes with hyperbaric oxygen therapy (HBOT). We reviewed our center's experience with HBOT as a rescue treatment for spinal cord ischemia post-CAR in addition to standard treatment. METHODS: A retrospective review of the University Health Network's Hyperbaric Medicine Unit treatment database identified HBOT sessions for patients with SCI post-CAR between January 2013 and June 2021. Mean estimates of overall motor function scores were determined for postoperative, pre-HBOT, post-HBOT (within 4 hours of the final HBOT session), and at the final assessment (last available in-hospital evaluation) using a linear mixed model. A subgroup analysis compared the mean estimates of overall motor function scores between improvement and non-improvement groups at given timepoints. Improvement of motor function was defined as either a ≥2 point increase in overall muscle function score in patients with paraparesis or an upward change in motor deficit categorization (para/monoplegia, paraparesis, and no deficit). Subgroup analysis was performed by stratifying by improvement or non-improvement of motor function from pre-HBOT to final evaluation. RESULTS: Thirty patients were treated for SCI. Pre-HBOT, the motor deficit categorization was 10 paraplegia, three monoplegia, 16 paraparesis, and one unable to assess. At the final assessment, 14 patients demonstrated variable degrees of motor function improvement; eight patients demonstrated full motor function recovery. Seven of the 10 patients with paraplegia remained paraplegic despite HBOT. The estimated mean of overall muscle function score for pre-HBOT was 16.6 ± 2.9 (95% confidence interval [CI], 10.9-22.3) and for final assessment was 23.4 ± 2.9 (95% CI, 17.7-29.1). The estimated mean difference between pre-HBOT and final assessment overall muscle function score was 6.7 ± 3.1 (95% CI, 0.6-16.1). The estimated mean difference of the overall muscle function score between pre-HBOT and final assessment for the improved group was 16.6 ± 3.5 (95% CI, 7.5-25.7) vs -4.9 ± 4.2 (95% CI, -16.0 to 6.2) for the non-improved group. CONCLUSIONS: HBOT, in addition to standard treatment, may potentially improve recovery in spinal cord function following SCI post-CAR. However, the potential benefits of HBOT are not equally distributed among subgroups.

Perioperative Blood Transfusion Is Associated with Worse 30-Day Mortality and Complications After Thoracic Endovascular Aortic Repair.

BACKGROUND: It is not uncommon for patients requiring vascular surgery, and in particular aortic surgery, to have increased requirements for blood transfusion. However, studies examining the effects of perioperative transfusion for thoracic endovascular aortic repair (TEVAR) are limited. Using large multicenter data, we aimed to study the impact of perioperative blood transfusion on 30-day mortality and complications after TEVAR. METHODS: A total of 9,263 patients who underwent TEVAR were included in this retrospective study from the multicenter Vascular Quality Initiative cohort spanning 2010-2022. We excluded patients who were post-traumatic, anemic (World Health Organization criteria: hemoglobin < 12 g/dl and < 13 g/dl for females and males respectively), who underwent open conversions or presented with ruptured aneurysms. Primary outcomes were 30-day mortality and stroke. Secondary outcomes were postop congestive heart failure (CHF), respiratory complications, spinal cord ischemia (SCI), myocardial infarction (MI) and any postop complications (composite variable). Poisson regression with robust variance was performed to determine the risk of post op outcomes comparing patients who received red blood cells (RBCs) to those who did not. RESULTS: Comparing patients without any transfusion (n = 8,223), perioperative transfusion of 1-3 units (n = 735) was associated with 3-fold increased risk of 30-day mortality (adjusted relative risk [aRR] 3.30, 95% confidence interval [CI] 2.39,4.57, P < 0.001), almost 2-fold increased risk of stroke (aRR 1.98, 95% CI 1.24,3.15, P = 0.004), 2.7-fold increased risk of SCI (aRR 2.66, 95% CI 1.87-3.77, P < 0.001), 3-fold increased risk of MI (aRR 3.40, 95% CI 2.30, 5.03, P < 0.001), 2-fold increased risk of CHF (aRR 2.04, 95% CI 1.09, 3.83, P = 0.03), 3.5-fold increased risk of respiratory complications (aRR 3.49, 95% CI 2.67, 4.56, P < 0.001), and 2-fold increased risk of any postop complication (aRR 2.36, 95% CI 2.04, 2.73, P < 0.001). These effects were even higher in patients transfused 4 or more units (n = 305) than seen in the effects seen in those transfused 1-3 units; comparing each group to patients who received none. CONCLUSIONS: In hemodynamically stable patients undergoing TEVAR for nonemergent/emergent and nontraumatic indications, transfusion of any amount perioperatively is associated with worse 30-day mortality, stroke, SCI, MI, CHF, and respiratory complications. A conservative transfusion approach and multidisciplinary care to identify complications and rescue TEVAR patients who receive any amount of RBCs perioperatively might help improve outcomes. Future studies to understand the mechanisms of outcomes for transfused patients are needed.

Incidence and risk factors for interval aortic events during staged fenestrated-branched endovascular aortic repair.

OBJECTIVE: Staged endovascular repair of complex aortic aneurysms with first-stage thoracic endovascular aortic repair may decrease the risk of spinal cord ischemia (SCI) associated with fenestrated-branched endovascular aortic repair (FB-EVAR) of thoracoabdominal aortic aneurysms or optimize the proximal landing zone in the cases requiring total aortic arch repair. However, a limitation of multistaged procedures is the risk of interval aortic events (IAEs) including mortality from a ruptured aneurysm. We aim to identify the incidence of and risk factors associated with IAEs during staged FB-EVAR. METHODS: This was a single-center, retrospective review of patients who underwent planned staged FB-EVAR from 2013 to 2021. Clinical and procedural details were reviewed. End points were the incidence of and risk factors associated with IAEs (defined as rupture, symptoms, and unexplained death) and outcomes in patients with or without IAEs. RESULTS: Of 591 planned FB-EVAR patients, 142 underwent first-stage repairs. Twenty-two did not have a planned second stage because of frailty, preference, severe comorbidities, or complications after the first stage and were excluded. The remaining 120 patients (mean age: 73 ± 6 years, 51% female) were planned for second-stage completion FB-EVAR and comprised our cohort. The incidence of IAEs was 13% (16 of 120). This included confirmed rupture in 6 patients, possible rupture in 4, symptomatic presentation in 4, and early unexplained interval death with possible rupture in 2. The median time to IAEs was 17 days (range: 2-101 days), and the median time to uncomplicated completion repairs was 82 days (interquartile range: 30-147 days). Age, sex, and comorbidities were similar between the groups. There were no differences in familial aortic disease, genetically triggered aneurysms, aneurysm extent, or presence of chronic dissection. Patients with IAEs had significantly larger aneurysm diameters than those without IAEs (76.6 vs 66.5 mm, P ≤ .001). This difference persisted with indexing for body surface area (aortic size index: 3.9 vs 3.5 cm/m2, P = .04) and height (aortic height index: 4.5 vs 3.9 cm/m, P ≤ .001). IAE mortality was 69% (11 of 16) compared with no perioperative deaths for those with uncomplicated completion repairs. CONCLUSIONS: The incidence of IAEs was 13% in patients planned for staged FB-EVAR. This represented a notable morbidity, including rupture, which must be balanced with SCI and landing zone optimization when planning repair. Larger aneurysms, especially when adjusted for body surface area, are associated with IAEs. Minimizing time between stages vs single-stage repairs for larger (>7 cm) complex aortic aneurysms in patients with reasonable SCI risk should be considered when planning repair.

Spinal cord ischemia rates and prophylactic spinal drainage in patients treated with fenestrated/branched endovascular repair for thoracoabdominal aneurysms.

OBJECTIVE: Spinal cord ischemia (SCI) is a devastating complication after thoracoabdominal aortic aneurysm (TAAA) repair. The benefit of prophylactic cerebrospinal fluid drainage (pCSFD) to prevent SCI is still under investigation. The aim of this study was to evaluate the SCI rate and the impact of pCSFD following complex endovascular repair (fenestrated or branched endovascular repair [F/BEVAR]) for type I to IV TAAA. METHODS: The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement was followed. A single-center retrospective study was conducted, including all consecutive patients, managed for TAAA type I to IV using F/BEVAR, between January 1, 2018, and November 1, 2022, for degenerative and post-dissection aneurysms. Patients with juxta- or pararenal aneurysms were excluded, as well as cases managed urgently for aortic rupture or acute dissection. After 2020, pCSFD in type I to III TAAAs was abandoned and replaced by therapeutic CSFD (tCSFD), performed only in patients presenting SCI. The primary outcome was the perioperative SCI rate for the entire cohort and the role of pCSFD for type I to III TAAAs. RESULTS: In total, 198 patients were included (mean age, 71.1±3.4 years; 81.8% males), including 50.5% with type I to III TAAA. The primary technical success was 94.9%. The perioperative mortality was 2.5%. and the major adverse cardiovascular event (MACE) rate was 10.6%; 4.5% presented SCI of any type (2.5% paraplegia). When comparing the SCI group with the remaining cohort, patients with SCI presented higher MACE (66.7% vs 7.9%; P < .001) rate and longer intensive care unit stay (3.5 vs 1 day; P = .002). Following type I to III repair, similar SCI, paraplegia, and paraplegia with no recovery rates were reported in the pCSFD and tCSFD groups (7.3% vs 5.1%; P = .66; 4.8% vs 3.3%; P = .72; and 2% vs 0%; P = .37). CONCLUSIONS: The incidence of SCI after TAAA I to IV endovascular repair was low. SCI was associated with significantly increased MACE and intensive care unit stay. The prophylactic use of CSFD in type I to III TAAAs was not associated with lower SCI rates and may not be justified routinely.

Spinal drain-related complications after complex endovascular aortic repair using a prophylactic automated volume-directed drainage protocol.

OBJECTIVE: A common measure to lower the risk for spinal cord ischemia (SCI) during complex endovascular aortic repair (cEVAR) is prophylactic cerebrospinal fluid drainage (CSFD). This method has caused controversy because of drain-related complications. Spinal drains are usually pressure directed. The objective of this study was to evaluate the risk of CSFD-related complications and SCI within the context of an automated volume-directed drain protocol. METHODS: This is a retrospective, single-center study of all cEVARs with CSFD at a tertiary vascular center between January 2014 and December 2020. Demographics, complications, and spinal drain data were recorded. All drainages were volume based using an automatic drainage system (LiquoGuard7; Möller Medical GmbH). Spinal drain complications were categorized as disabling and nondisabling according to the modified Rankin scale. The primary end point was any CSFD-related complication. RESULTS: A total of 448 cEVAR patients were identified, of whom 147 (32.8%) had prophylactic CSFD. The mean age was 69 years (63% male). The most common pathology (61%) was thoracoabdominal aortic aneurysm, and the most common procedure was branched EVAR (55.1%). Eighteen (12.2%) patients developed a CSFD-related complication, whereof three (2%) were disabling. Nineteen (13%) patients developed SCI: 12 (8.4%) paraparetic, 5 (3.4%) paraplegic, and 2 (1.4%) paresthesias. Of these, 13 (68%) had full reversal of symptoms, whereas 6 patients (4%) had residual symptoms and were deemed disabling. Drain-related complications were more common in patients with SCI (31.6%) compared with those without (9.4%, P = .014). In the latter group, only two patients (1.6%) developed a disabling drain-related complication. CONCLUSIONS: Selective use of prophylactic, automated volume-directed CSFD in patients at high risk for SCI was associated with a high incidence of complications and should be used with caution. Among those developing SCI, reversal was achieved frequently with increased CSFD volume, but at the price of more bleeding complications.

Cancer-associated spinal cord infarction: A systematic review and analysis of survival predictors.

OBJECTIVE: The association between spinal cord infarction (SCI) and cancer is an infrequent condition but requires an accurate diagnosis to establish the appropriate treatment. Clinical features and prognosis of cancer-associated SCI have never been assessed. The aim of this systematic review is to describe the characteristics and outcomes of patients with cancer-associated SCI. Illustratively, a case of ovarian cancer-related SCI is presented. MATERIAL AND METHODS: Two authors independently analysed three different bibliographic databases looking for cancer-associated SCI case reports and case series. Data regarding age, sex, cardiovascular risk factors (CVRF), history of known cancer, infarction localization, spinal cord syndrome, Zalewski criteria classification, mechanism of ischemia, diagnostic tests, treatment and functional outcome were registered. A statistical analysis was carried out to identify factors related to mortality and survival time. RESULTS: A total of 48 articles met the inclusion criteria and 52 patients were identified. The median age was 62 years. The most frequent neoplasm was intravascular large B-cell lymphoma. The median survival time was 17.4 weeks and the cumulative probability of survival at 12 months was 16.3%. In the group of deceased patients there was a higher proportion of malignant neoplasms than in those who survived (94.7% vs. 5.3%, p < 0.01). There were no statistically significant differences in terms of mortality or survival time depending on age, previously known cancer or CVRF. CONCLUSION: Cancer-associated SCI entails a poor outcome. Mortality is increased in patients with malignant neoplasm. No other prognosis factors could be identified.

Risk Factors Associated with Spinal Cord Ischemia During Aortic Aneurysm Repair.

BACKGROUND: The risk of spinal cord ischemia (SCI) with aortic aneurysm repair can cause significant neurological morbidity. Prevention of SCI is critical. We sought to identify risk factors that predispose to SCI that may guide strategies to mitigate the occurrence of SCI during and following these procedures. METHODS: This study includes all adults who underwent atraumatic, unruptured, thoracic, and suprarenal aortic aneurysm repairs (endovascular or open) at our institution over 11 years (2010-2020). Our database included patient demographics, aneurysm anatomic features, and operative characteristics and an extreme gradient boost (XGB) machine method was used to develop a predictive model for SCI. The model was trained on an 80% randomly stratified cohort of the data and tested on the remaining 20% testing cohort. Shapley values were used to determine the most important predictive factors of SCI and decision trees were used to identify risk factor threshold values and highest risk factor combinations. RESULTS: Information was collected for 174 adult patients undergoing thoracic and suprarenal aortic repair from 2010 to 2020. Fifty eight percent of the patients were male. Ninety seven (55.7%) patients had open aortic repair and 87 (44.3%) had endovascular repair. Twenty seven (15%) of all patients had major complications and were considered to have SCI. The XGB model converged over the training cohort with a testing cohort accuracy of 0.841 [Sensitivity = 75%, Specificity = 68%] and area under the curve of receiver operating characteristic of 0.774. The XGB model identified older age (> 65 years), history of neurologic disease, hyperlipidemia, diabetes, coronary artery disease, heart failure, poor renal function, < 6 months since last aortic repair, chronic anticoagulant use, preoperational anemia (Hemoglobin < 9), thrombocytopenia (platelet < 90,000), coagulopathy (prothrombin time > 15s and activated partial thromboplastin time > 40s), hypotension (mean arterial pressure < 70 mm Hg), longer operations (> 100 min), aneurysms longer than 5 cm, and anatomic location of aneurysm caudal to T-11 as risk factors for SCI in all types of aortic repair. Diabetic and heart failure patients undergoing longer operations (> 100 min) with thrombocytopenia or aneurysms longer than 5 cm were at the highest risk. CONCLUSIONS: The XGB model accurately identified risk factors of SCI with aortic aneurysm repair that may guide patient selection, timing of surgery, and strategies to minimize the risk of SCI.

Reappraisal of the role of motor and somatosensory evoked potentials during open distal aortic repair.

OBJECTIVE: Intraoperative motor and somatosensory evoked potentials have been applied to monitor spinal cord ischemia during repair. However, their predictive values remain controversial. The purpose of this study was to evaluate the impact of motor evoked potentials and somatosensory evoked potentials on spinal cord ischemia during open distal aortic repair. METHODS: Our group began routine use of both somatosensory evoked potentials and motor evoked potentials at the end of 2004. This study used a historical cohort design, using risk factor and outcome data from our department's prospective registry. Univariate and multivariable statistics for risk-adjusted effects of motor evoked potentials and somatosensory evoked potentials on neurologic outcome and model discrimination were assessed with receiver operating characteristic curves. RESULTS: Both somatosensory evoked potentials and motor evoked potentials were measured in 822 patients undergoing open distal aortic repair between December 2004 and December 2019. Both motor evoked potentials and somatosensory evoked potentials were intact for the duration of surgery in 348 patients (42%). Isolated motor evoked potential loss was observed in 283 patients (34%), isolated somatosensory evoked potential loss was observed in 18 patients (3%), and both motor evoked potential and somatosensory evoked potential loss were observed in 173 patients (21%). No spinal cord ischemia occurred in the 18 cases with isolated somatosensory evoked potential loss. When both signals were lost, signal loss happened in the order of motor evoked potentials and then somatosensory evoked potentials. Immediate spinal cord ischemia occurred in none of those without signal loss, 4 of 283 (1%) with isolated motor evoked potential loss, and 15 of 173 (9%) with motor evoked potential plus somatosensory evoked potential loss. Delayed spinal cord ischemia occurred in 12 of 348 patients (3%) with intact evoked potentials, 24 of 283 patients (8%) with isolated motor evoked potentials loss, and 27 of 173 patients (15%) with motor evoked potentials + somatosensory evoked potentials loss (P < .001). Motor evoked potentials and somatosensory evoked potentials loss were each independently associated with spinal cord ischemia. For immediate spinal cord ischemia, no return of motor evoked potential signals at the conclusion of the surgery had the highest odds ratio of 15.87, with a receiver operating characteristic area under the curve of 0.936, whereas motor evoked potential loss had the highest odds ratio of 3.72 with an area under the curve of 0.638 for delayed spinal cord ischemia. CONCLUSIONS: Somatosensory evoked potentials and motor evoked potentials are both important monitoring measures to predict and prevent spinal cord ischemia during and after open distal aortic repairs. Intraoperative motor evoked potential loss is a risk for immediate and delayed spinal cord ischemia after open distal aortic repair, and somatosensory evoked potential loss further adds predictive value to the motor evoked potential.

Strategies for prevention and treatment of spinal cord ischemia during F/BEVAR.

Spinal cord ischemia (SCI) after endovascular aortic repair is associated with significant morbidity and mortality. Understanding of the pathogenesis and physiologic mechanisms of SCI dictates prevention and treatment when neurologic deficits occur. Currently used or proposed preventive modalities include staged repair, temporary aneurysm sac perfusion, segmental artery embolization, and management of hemodynamic parameters based on decades of experience with open thoracoabdominal and thoracic endovascular aortic repair. The role of cerebrospinal fluid drainage in prevention of SCI remains an area of clinical equipoise. "Rescue maneuvers" when neurologic deficits develop are generally consistent and include cerebrospinal fluid drainage, hemodynamic management, and elevated hemoglobin goals. The role of team communication and education in expedient recognition and treatment initiation in SCI is paramount. Advances in spinal cord protective practices and new therapies in spinal cord injury may play a role in future prevention and treatment protocols. Additional research is needed to further define the optimal use of currently accepted and emerging therapies, and current management practices, to improve patient outcomes with regard to SCI after branched and fenestrated endovascular aortic repair.

Staging Endovascular Thoracic and Thoracoabdominal Aortic Aneurysm Repairs and the Risk of Post-operative Spinal Cord Ischemia.

OBJECTIVE: Staged aortic aneurysm repair is one method used to decrease the risk of spinal cord ischemia (SCI) following endovascular aortic intervention. Sequential sacrifice of arteries perfusing the spine may allow for improved spinal perfusion through the development of collateral networks over time. To evaluate the impact of staging endovascular aortic aneurysm repairs on SCI, we conducted a conservative analysis of Vascular Quality Initiative (VQI) data. METHODS: De-identified VQI data were queried for cases of endovascular thoracic and thoracoabdominal aneurysm repairs from year 2014 to 2019. Cases were selected based on inclusion criteria: aneurysmal disease, no ruptures, no prior aortic surgeries, no retreatments, and only cases with complete data on aortic zones and SCI. Chi-square, Student's t-tests, and Mann-Whitney U tests were used for univariable analyses, as appropriate. Logistic regression analyses were used to identify independent predictors of outcome. RESULTS: There were 116 staged aortic repairs (SARs) (8.2%) performed out of a total of 1421 endovascular aortic repairs that fit study criteria. The overall rate of SCI within the study cohort was 3.4% (n = 48). The distribution of SARs and SCI events according to aortic zone coverage are displayed in Table 1. Patients who underwent staged endovascular aortic repairs had higher rates of SCI, pre-op spinal drain placement, non-African-American race, COPD, smoking history, positive stress tests, aspirin and statin use, increased estimated blood loss, physician-modified endografts, number of aortic zones covered, lower pre-op hemoglobin levels, larger aneurysm sac size, fusiform aneurysms, and longer total procedure times, Table 2. After adjusting for factors associated with SCI, a priori, and factors with a P < 0.1 univariable analysis, SAR was not associated with SCI (odds ratio [OR] = 1.86, 95% confidence interval [CI] = 0.77-4.50, P = 0.17). Of the six factors associated with SCI on univariable analysis, only procedure time ≥6 hours (OR = 2.49, 95% CI = 1.09-5.70, P = 0.031) and the number of aortic zones covered (OR = 1.15, 95% CI = 1.00-1.32, P = 0.047) were predictive of SCI. Staged repairs had a lower proportion of permanent SCI (38%, 3 of 8 cases) compared with repairs that were not staged (68%, 27 of 40 cases), with a relative risk reduction of 44% for those who developed SCI, P = 0.21. CONCLUSIONS: In a large national data set, SARs were performed for patients with more extensive aortic disease. SARs were only performed in about 8% of cases and the rate of SCI remained low. After adjusting for baseline comorbidities, extent of aortic disease, and other factors that may potentiate SCI, staged aortic aneurysm repair had a similar risk of SCI compared with non-staged repairs. However, there was a trend toward decreased permanent SCI risk in the SAR group.

Acute to Subacute Spinal Cord Infarction Mimicking Acute Multiple Sclerosis: Usefulness of Diffusion-weighted MRI for Diagnosis.

BACKGROUND: Spinal Cord Infarction (SCI) is difficult to diagnose because of its rarity, unknown etiology, and unestablished diagnostic criteria. Additionally, the timeline of SCI has not been studied in detail, as few studies using Diffusion-Weighted Image (DWI) sequences of the spine of a small target population have been previously conducted. CASE STUDY: A 56-year-old male with underlying arrhythmia suddenly developed visual field defects on the right side, pain in the left upper extremity, and a tingling sensation in the left hand. Brain Magnetic resonance imaging (MRI) revealed acute to subacute stages of multifocal brain infarction. On additional cervical spinal MRI, it showed atypical MRI findings of SCI, considered late acute to early subacute phase, which were similar to those seen in the acute phase of multiple sclerosis (MS). Additional DWI revealed restricted diffusion. From these findings, it could be inferred that the patient's SCI occurred at the same time as the multifocal brain infarctions caused by atrial fibrillation. CONCLUSION: A DWI sequence of spine MRI could be helpful in the diagnosis of acute to subacute phase SCI and in differentiating with acute MS.

Mapping the collateral network: Optimal near-infrared spectroscopy optode placement.

BACKGROUND: Paraplegia after extensive aortic procedures is a disastrous complication, and maintenance of adequate spinal cord perfusion/oxygenation is pivotal to its prevention. Collateral network (CN) near-infrared spectroscopy (cnNIRS) has been introduced as a noninvasive method for indirect spinal cord oxygenation monitoring. However, the CN has not been investigated in its entirety using this monitoring modality. This study aimed to identify the optimal cnNIRS positioning in an acute large animal model for routine clinical use. METHODS: The paraspinous CN was measured from the high thoracic region to the low lumbar region (T4-L5) using cnNIRS in 10 juvenile pigs (plus reference data from 7 animals) during aortic ischemia and reperfusion. These data were compared with data on direct regional tissue perfusion of the CN and the spinal cord. RESULTS: After aortic cross-clamping, cnNIRS at the mid-thoracic to the low lumbar level decreased rapidly to a nadir at 10 minutes of distal ischemia (mean difference, 18.3 ± 11% to 44.5 ± 9%; P < .001 to .045), with more pronounced changes in the caudal regions. High thoracic cnNIRS remained stable (mean difference, 4.3 ± 4%; P = .915). Measurements of cnNIRS, CN, and spinal cord regional perfusion demonstrated comparable curve progressions starting from the mid-thoracic region (r = 0.5-0.7; P < .001). CONCLUSIONS: cnNIRS is capable of detecting relevant changes during ischemia and reperfusion from the mid-thoracic level downward with characteristic oxygenation patterns corresponding to CN and spinal cord regional perfusion. For extensive aortic procedures, noninvasive cnNIRS placement appears to be useful from the mid-thoracic level (T7-T9) to the lower lumbar level (L3-L5) and also may serve as a versatile monitoring method for procedures limited to the proximal thoracic aorta.

A systematic review and meta-analysis of the occurrence of spinal cord ischemia after endovascular repair of thoracoabdominal aortic aneurysms.

OBJECTIVE: The rate of endovascular repair of thoracoabdominal aortic aneurysms (TAAA-ER) has increased considerably in recent years. Although the mortality and morbidity rates have improved, the incidence of spinal cord ischemia (SCI) has not declined significantly. The aim of the present systematic review and meta-analysis was to examine the SCI rates with respect to the efficacy of the different approaches. METHODS: Cohort studies and case series (>20 patients) reporting SCI rates after TAAA-ER were eligible for inclusion. The primary outcome measure was the evaluation of SCI. The moderators considered were primarily the staged vs nonstaged approach, the use of cerebrospinal fluid drainage (CSFD), and TAAA extension. The permanent SCI and mortality rates were extracted. RESULTS: A total of 27 studies with 2333 patients were included in the meta-analysis. The pooled estimate for SCI was 11% (95% confidence interval [CI], 8%-15%; I2, 79%). For extent I, II, III, and V TAAA, the pooled SCI rate was 13% (95% CI, 10%-17%; I2, 69%). For extent IV TAAA, the pooled SCI rate was 6% (95% CI, 3%-10%; I2, 62%). A staged TAAA-ER approach was used in 20 studies and a nonstaged approach in 8 (1 study had included both). A lower pooled SCI rate was identified after staged than after nonstaged TAAA-ER (9% vs 18%, respectively; P = .02). Staging was accomplished in >1 month in nine studies and ≤1 month in two studies, leading to similar SCI rates (7% vs 11%, respectively; P = .26). The method of staging (thoracic endoprosthesis or temporary aortic sac perfusion) did not affect the SCI rates. Symptomatic CSFD was associated with a similar pooled rate of SCI compared with prophylactic CSFD (10% vs 10%, respectively; P = .99). The pooled permanent SCI rate was 6% (6% for extent I, II, III, and V TAAA; and 3% for extent IV TAAA). The pooled rate of 30-day mortality was 7%, with a similar incidence for the staged and nonstaged approaches (6% vs 9%, respectively). Interstage mortality was reported in 9 studies, with a pooled estimate rate of 1.6%. CONCLUSIONS: SCI had occurred in 11% of TAAA-ER, and one half of these cases were permanent. A staged approach can reduce SCI rates independently of the timing and method adopted. The overall mortality rate for staged TAAA-ER was 7%, with one fifth of the deaths (1.6%) occurring between stages.

Is Surfer's myelopathy an acute hyperextension-induced myelopathy? A systematic synthesis of case studies and proposed diagnostic criteria.

BACKGROUND: Surfer's myelopathy is a rare complication of spinal hyperextension originally described in novice surfers. However, reports from patients practicing different activities had risen. AIM: To systematically synthesize the epidemiological and clinical evidence on acute hyperextension-induced myelopathy ("Surfer's myelopathy") and propose new diagnostic criteria. METHODS: We systematically searched four databases for all observational and case studies on the topic. We performed a narrative synthesis to propose diagnostic criteria and tested the criteria retrospectively on the included cases. A case report is also presented. RESULTS: Forty-two articles reporting 104 cases (median age 19 years, slightly male predominance) were included. All cases reported a nontraumatic hyperextension event (58% after surfing). All of the cases presented pain of hyperacute onset. The most frequent clinical feature was bladder or bowel dysfunction (84%). The thoracic region was the most frequently affected (87%) with longitudinal involvement until the conus (67%). At discharge or follow-up, 52% partially recovered. We propose five diagnostic criteria with three levels of certainty (definite, probable, and possible): (1) nontraumatic spine hyperextension activity (in individuals with no pre-existent spinal disease); (2) hyperacute onset (with acute pain onset); (3) spinal cord injury clinic (motor, sensory, or autonomic deficit); (4) MRI findings with central spinal cord abnormalities (multiple segments); and (5) no other alternative diagnosis. We identified 88% definite and 12% probable/possible cases. CONCLUSION: The acute hyperextension-induced myelopathy could occur not only during surfing but also during other activities. Therefore, increased awareness and education among sports communities and general physicians are needed.

Optimization of factors for the prevention of spinal cord ischemia in thoracic endovascular aortic repair.

OBJECTIVES: Spinal cord ischemia following thoracic endovascular aortic repair (TEVAR) is a devastating complication. This study seeks to demonstrate how a standardized protocol to prevent spinal cord ischemia affects incidence in patients undergoing TEVAR. METHODS: Using CPT codes 33880 and 33881, all TEVAR procedures performed at a single tertiary care center from January 2017 to December 2018 were examined. Patients who had concomitant ascending aortic repairs or a TEVAR for traumatic indications were excluded from analysis, leaving 130 TEVAR procedures. Comorbid conditions, procedural characteristics, extent of coverage, peri-procedural management strategies, and post-operative outcomes were collected and analyzed retrospectively. RESULTS: One hundred thirty patients undergoing TEVAR were examined for four perioperative variables: postoperative hemoglobin greater than 10 g/dL, subclavian revascularization, preoperative spinal drain placement, and somatosensory evoked potential monitoring (SSEP). All conditions were met in 46.2% (60/130) of procedures; 37.8% (28/74) in emergent/urgent cases and 61.5% (32/52) in elective cases. Of patients who required subclavian coverage, 87.1% (54/62) underwent subclavian revascularization; 70.8% (92/130) of patients received spinal drains preoperatively; 68.5% (89/130) of patients had SSEP monitoring; 73.8% (93/130) of patients obtained a postoperative hemoglobin of >10 g/dL. Out of all patients, two (1.5%) developed spinal cord ischemia. CONCLUSION: Incidence of spinal cord ischemia in our cohort was low at 1.5% (2/130). Individual and bundled interventions for the prevention of spinal cord ischemia were unable to demonstrate a statistically significant effect given the low rate. Nonetheless, we advocate for a proactive approach for the prevention of spinal cord ischemia given our experience in this complex population.

Prior infrarenal aortic surgery is not associated with increased risk of spinal cord ischemia after thoracic endovascular aortic repair and complex endovascular aortic repair.

OBJECTIVE: Patients with prior infrarenal aortic intervention represent an increasing demographic of patients undergoing thoracic endovascular aortic repair (TEVAR) and/or complex EVAR. Studies have suggested that prior abdominal aortic surgery is a risk factor for spinal cord ischemia (SCI). However, these results were largely based on single-center experiences with limited multi-institutional and national data that had assessed the clinical outcomes for these patients. The objective of the present study was to evaluate the effect of prior infrarenal aortic surgery on the occurrence of SCI. METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was retrospectively reviewed to identify all patients aged ≥18 years who had undergone TEVAR and/or complex EVAR from January 2012 to June 2020. Patients with previous thoracic or suprarenal aortic repair were excluded. The baseline and procedural characteristics and postoperative outcomes were compared between TEVAR and/or complex EVAR with and without previous infrarenal aortic repair. The primary outcome was postoperative SCI. The secondary outcomes included postoperative hospital length of stay, bowel ischemia, renal ischemia, and 30-day mortality. Multivariate regression was used to determine the independent predictors of postoperative SCI. Additional analysis was performed of the patients who had undergone isolated TEVAR. RESULTS: A total of 9506 patients met the inclusion criteria: 8691 (91.4%) had not undergone prior infrarenal aortic repair and 815 (8.6%) had undergone previous infrarenal aortic repair. Patients with previous infrarenal repair were older with an increased prevalence of chronic kidney disease (P = .001) and cardiovascular risk factors, including hypertension, chronic obstructive pulmonary disease, and positive smoking history (P < .001). These patients also presented with a larger maximal aortic diameter (6.06 ± 1.47 cm vs 5.15 ± 1.76 cm; P < .001) and required more stent-grafts (P < .001) with increased intraoperative blood transfusion requirements (P < .001), and longer procedure times (P < .001). Univariate analysis demonstrated no differences in postoperative SCI, postoperative hospital length of stay, bowel ischemia, or renal ischemia between the two groups. The 30-day mortality was significantly higher in patients with prior infrarenal repair (P = .001). On multivariate regression, prior infrarenal aortic repair was not a predictor of postoperative SCI. In contrast, aortic dissection (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.26-2.16; P < .001), number of stent-grafts deployed (OR, 1.45; 95% CI, 1.30-1.62; P < .001), and units of packed red blood cells transfused intraoperatively (OR, 1.33; 95% CI, 1.03-1.73; P = .032) were independent predictors of postoperative SCI. CONCLUSIONS: Although the patients in the TEVAR and/or complex EVAR group with prior infrarenal aortic repair constituted a sicker cohort with higher 30-day mortality, the rate of SCI was comparable to that of the patients without prior repair. Previous infrarenal repair was not associated with the risk of SCI.