Lumbar Cerebrospinal Fluid Drainage for Thoracoabdominal Aortic Surgery

How Would I Treat My Own Thoracoabdominal Aortic Aneurysm: Perioperative Considerations From the Anesthesiologist Perspective

A thoracoabdominal aortic aneurysm (TAAA) can be potentially life-threatening due to its associated risk of rupture. Thoracoabdominal aortic aneurysm repair, performed as endovascular repair and/or open surgery, is the recommended therapy of choice. Hemodynamic instability, severe blood loss, and spinal cord or cerebral ischemia are some potential hazards the perioperative team has to face during these procedures. Therefore, preoperative risk assessment and intraoperative anesthesia management addressing these potential hazards are essential to improving patients' outcomes. Based on a presented index case, an overview focusing on anesthetic measures to identify perioperatively and manage these risks in TAAA repair is provided.

Anesthesia management for thoracoscopic resection of a huge intrathoracic meningocele: a case report

BACKGROUND

Diagnosed intrathoracic meningocele is an uncommon complication of neurofibromatosis type 1. We report an anesthesia management for a rare case undergoing thoracoscopic resection of a huge intrathoracic meningocele.

CASE PRESENTATION

A 51-year-old woman was scheduled for thoracoscopic meningectomy under general anesthesia. We monitored intrathecal pressure during anesthesia to prevent a decrease in intrathecal pressure. During surgery, the intrathecal pressure occasionally increased by around 5 cmH2O immediately after the insertion of the drainage tube and occasionally decreased by up to 10 cmH2O during the careful slow aspiration of the cerebrospinal fluid (CSF). The pressure rapidly recovered after the interruption of the procedures. She was discharged on postoperative day 4 without major complications.

CONCLUSIONS

The CSF pressure was fluctuated by procedures during thoracoscopic resection of a huge meningocele. A CSF pressure monitoring was useful to detect the sudden change of CSF pressure immediately, which can cause intracranial hemorrhage.

How We Would Treat Our Own Thoracoabdominal Aortic Aneurysm

This manuscript is intended to provide a comprehensive review of the current state of knowledge on endovascular repair of thoracoabdominal aortic aneurysms (TAAAs). The management of these complex aneurysms requires an interdisciplinary and patient-specific approach in high-volume centers. An index case is used to discuss the diagnosis and treatment of a patient undergoing fenestrated-branched endovascular aneurysm repair for a TAAA.

Retrospective investigation of >400 patients undergoing thoracic endovascular aortic repair with or without cerebrospinal fluid drainage

OBJECTIVES

The aim of this study was to analyse the risks and benefits of cerebrospinal fluid drainage (CSFD) placement in patients undergoing thoracic endovascular aortic repair.

METHODS

Between 2009 and 2020, 411 patients underwent thoracic endovascular aortic repair in 1 institution where 236 patients (57%) received a preoperative CSFD. Patient and outcome characteristics were retrospectively analysed and compared between patients with and without preoperative CSFD placement.

RESULTS

Preoperative CSFD was performed significantly more frequently in elective patients, especially those undergoing distal stent graft extension following frozen elephant trunk-stent placement (P < 0.001). Significantly fewer CSFD was placed in patients with acute aortic injury (P < 0.001). The incidence of permanent spinal cord ischaemia (SCI) was higher in patients without preoperative CSFD [10 patients (2%) vs 1 patient (0.2%), P = 0.001]. Postoperative CSFD was placed in 3 patients (0.7%). Severe CSFD-associated complications affected 2 patients (0.5%) namely, a subdural spinal haematoma causing permanent paraplegia in one of those 2 patients.

CONCLUSIONS

CSFS placement is associated with low procedural risk and can potentially help to prevent SCI. However, the SCI incidence is most likely also associated with other preoperative factors including the patient's haemodynamics. Hence, a general recommendation for placing a preoperative CSFD cannot be made when relying on the present evidence.

Cerebrospinal Fluid Diversion for Refractory Intracranial Hypertension in Traumatic Brain Injury: A Single Center Experience

BACKGROUND

Diversion of cerebrospinal fluid (CSF) is a common neurosurgical procedure for control of intracranial pressure (ICP) in the acute phase after traumatic brain injury (TBI), where medical management is insufficient. CSF can be drained via an external ventricular drain (EVD) or, in selected patients, via a lumbar (external lumbar drain [ELD]) drainage catheter. Considerable variability exists in neurosurgical practice on their use.

METHODS

A retrospective service evaluation was completed for patients receiving CSF diversion for ICP control after TBI, from April 2015 to August 2021. Patients were included whom fulfilled local criteria deeming them suitable for either ELD/EVD. Data were extracted from patient notes, including ICP values pre/postdrain insertion and safety data including infection or clinically/radiologically diagnosed tonsillar herniation.

RESULTS

Forty-one patients were retrospectively identified (ELD = 30 and EVD = 11). All patients had parenchymal ICP monitoring. Both modalities affected statistically significant decreases in ICP, with relative reductions at 1, 6, and 24 hour pre/postdrainage (at 24-hour ELD P < 0.0001, EVD P < 0.01). Similar rates of ICP control failure, blockage and leak occurred in both groups. A greater proportion of patients with EVD were treated for CSF infection than with ELD. One event of clinical tonsillar herniation is reported, which may have been in part attributable to ELD overdrainage, but which did not result in adverse outcome.

CONCLUSIONS

The data presented demonstrate that EVD and ELD can be successful in ICP control after TBI, with ELD limited to carefully selected patients with strict drainage protocols. The findings support prospective study to formally determine the relative risk-benefit profiles of CSF drainage modalities in TBI.

Unusual presentation of acute ruptured penetrating aortic ulcer of descending thoracic aorta with right hemothorax

Right-sided hemothorax is a rare presentation of ruptured penetrating aortic ulcers. A 72-year-old female presented to the hospital with a penetrating aortic ulcer of the mid-thoracic aorta and a right-sided hemothorax. The patient was taken for thoracic endovascular aortic repair and right-sided tube thoracostomy. The diagnosis was complicated by the patient's history of pacemaker placement causing prominent venous collaterals in the mediastinum. The postoperative course was complicated by lower extremity weakness, requiring lumbar cerebrospinal fluid drain placement. The patient regained full function of her lower extremities. This case illustrates that patients with ruptured acute aortic syndromes may present with right hemothorax, so index of suspicion should remain high in this population.

Practice of neuromonitoring in open and endovascular thoracoabdominal aortic repair-an international expert-based modified Delphi consensus study

OBJECTIVES

Spinal cord injury is detrimental for patients undergoing open or endovascular thoracoabdominal aortic aneurysm (TAAA) repair. The aim of this survey and of the modified Delphi consensus was to gather information on current practices and standards in neuroprotection in patients undergoing open and endovascular TAAA.

METHODS

The Aortic Association conducted an international online survey on neuromonitoring in open and endovascular TAAA repair. In a first round an expert panel put together a survey on different aspects of neuromonitoring. Based on the answers from the first round of the survey, 18 Delphi consensus questions were formulated.

RESULTS

A total of 56 physicians completed the survey. Of these, 45 perform open and endovascular TAAA repair, 3 do open TAAA repair and 8 do endovascular TAAA repair. At least 1 neuromonitoring or protection modality is utilized during open TAAA surgery. Cerebrospinal fluid (CSF) drainage was used in 97.9%, near infrared spectroscopy in 70.8% and motor evoked potentials or somatosensory evoked potentials in 60.4%. Three of 53 centres do not utilize any form of neuromonitoring or protection during endovascular TAAA repair: 92.5% use CSF drainage; 35.8%, cerebral or paravertebral near infrared spectroscopy; and 24.5% motor evoked potentials or somatosensory evoked potentials. The utilization of CSF drainage and neuromonitoring varies depending on the extent of the TAAA repair.

CONCLUSIONS

The results of this survey and of the Delphi consensus show that there is broad consensus on the importance of protecting the spinal cord to avoid spinal cord injury in patients undergoing open TAAA repair. Those measures are less frequently utilized in patients undergoing endovascular TAAA repair but should be considered, especially in patients who require extensive coverage of the thoracoabdominal aorta.

Invasive Pressure Monitors: Leveling the Playing Field

Invasive pressure monitors are ubiquitous in cardiothoracic and vascular anesthesia. This technology allows beat-to-beat assessment of central venous, pulmonary, and arterial blood pressures during surgery, procedural interventions, and critical care. Education is commonly focused on the procedural aspects and the complications associated with the initial placement of these monitors without instruction on the technical concepts required for obtaining accurate data. Anesthesiologists must understand the fundamental concepts on which measurements are made to effectively use invasive pressure monitors, including pulmonary artery catheters, central venous catheters, intra-arterial catheters, external ventricular drains, and spinal or lumbar drains. This review will address important gaps in knowledge surrounding leveling and zeroing of invasive pressure monitors, emphasizing the impact of varied practice patterns on patient care.

Effect of cerebrospinal fluid drainage pressure in descending and thoracoabdominal aortic repair: a prospective multicenter observational study

PURPOSE

Cerebrospinal fluid drainage (CSFD) is recommended during open or endovascular thoracic aortic repair. However, the incidence of CSFD complications is still high. Recently, CSF pressure has been kept high to avoid complications, but the efficacy of CSFD at higher pressures has not been confirmed. We hypothesize that CSFD at higher pressures is effective for preventing motor deficits.

METHODS

This prospective observational study included 14 hospitals that are members of the Japanese Society of Cardiovascular Anesthesiologists. Patients who underwent thoracic and thoracoabdominal aortic repair were divided into four groups: Group 1, CSF pressure around 10 mmHg; Group 2, CSF pressure around 15 mmHg; Group 3, CSFD initiated when motor evoked potential amplitudes decreased; and Group 4, no CSFD. We assessed the association between the CSFD group and motor deficits using mixed-effects logistic regression with a random intercept for the institution.

RESULTS

Of 1072 patients in the study, 84 patients (open surgery, 51; thoracic endovascular aortic repair, 33) had motor deficits at discharge. Groups 1 and 2 were not associated with motor deficits (Group 1, odds ratio (OR): 1.53, 95% confidence interval (95% CI): 0.71-3.29, p = 0.276; Group 2, OR: 1.73, 95% CI: 0.62-4.82) when compared with Group 4. Group 3 was significantly more prone to motor deficits than Group 4 (OR: 2.56, 95% CI: 1.27-5.17, p = 0.009).

CONCLUSION

CSFD is not associated with motor deficits in thoracic and thoracoabdominal aortic repair with CSF pressure around 10 or 15 mmHg.

Anaesthesia for vascular emergencies - a state of the art review

In this state-of-the-art review, we discuss the presenting symptoms and management strategies for vascular emergencies. Although vascular emergencies are best treated at a vascular surgical centre, patients may present to any emergency department and may require both immediate management and safe transport to a vascular centre. We describe the surgical and anaesthetic considerations for management of aortic dissection, aortic rupture, carotid endarterectomy, acute limb ischaemia and mesenteric ischaemia. Important issues to consider in aortic dissection are extent of the dissection and surgical need for bypasses in addition to endovascular repair. From an anaesthetist's perspective, aortic dissection requires infrastructure for massive transfusion, smooth management should an endovascular procedure require conversion to an open procedure, haemodynamic manipulation during stent deployment and prevention of spinal cord ischaemia. Principles in management of aortic rupture, whether open or endovascular treatment is chosen, include immediate transfer to a vascular care centre; minimising haemodynamic changes to reduce aortic shear stress; permissive hypotension in the pre-operative period; and initiation of massive transfusion protocol. Carotid endarterectomy for carotid stenosis is managed with general or regional techniques, and anaesthetists must be prepared to manage haemodynamic, neurological and airway issues peri-operatively. Acute limb ischaemia is a result of embolism, thrombosis, dissection or trauma, and may be treated with open repair or embolectomy, under either general or local anaesthesia. Due to hypercoagulability, there may be higher numbers of acutely ischaemic limbs among patients with COVID-19, which is important to consider in the current pandemic. Mesenteric ischaemia is a rare vascular emergency, but it is challenging to diagnose and associated with high morbidity and mortality. Several peri-operative issues are common to all vascular emergencies: acute renal injury; management of transfusion; need for heparinisation and reversal; and challenging postoperative care. Finally, the important development of endovascular techniques for repair in many vascular emergencies has improved care, and the availability of transoesophageal echocardiography has improved monitoring as well as aids in surgical placement of endovascular grafts and for post-procedural evaluation.

External Lumbar Drainage for Refractory Intracranial Hypertension in Traumatic Brain Injury: A Systematic Review

Considerable variation exists in the clinical practice of cerebrospinal fluid diversion for medically refractory intracranial hypertension in patients with acute traumatic brain injury (TBI), which is achievable via lumbar or ventricular drainage. This systematic review sought to compile the available evidence for the efficacy and safety of the use of lumbar drains for intracranial pressure (ICP) control.

A systematic review of the literature was performed with the search and data extraction performed by two reviewers independently in duplicate. Nine independent studies were identified, enrolling 230 patients, 159 with TBI. Efficacy for ICP control was observed across all studies, with immediate and sustained effect, reducing medical therapy requirements. Lumbar drainage with medical therapy appears effective when used alone and as an adjunct to ventricular drainage. Safety reporting varied in quality. Clinical or radiological incidents of cerebral herniation (with an unclear relationship to lumbar drainage) were observed in 14/230 patients resulting in one incident of morbidity without adverse patient outcome.

The available data is generally poor in quality and volume, but supportive of the efficacy of lumbar drainage for ICP control. Few reports of adverse outcomes are suggestive of, but are insufficient to confirm, the safety of use in the appropriate patient and clinical setting. Further large prospective observational studies are required to generate sufficient support of an acceptable safety profile.

Prevention of Spinal Cord Injury during Thoracoabdominal Aortic Aneurysms Repair: What the Anaesthesiologist Should Know

Thoraco-abdominal aortic repair is a high-risk surgery for both mortality and morbidity. A major complication is paraplegia-paralysis due to spinal cord injury. Modern thoracic and abdominal aortic aneurysm repair techniques involve multiple strategies to reduce the risk of spinal cord ischemia during and after surgery. These include both surgical and anaesthesiologic approaches to optimize spinal cord perfusion by staging the procedure, guaranteeing perfusion of the distal aorta through various techniques (left atrium–left femoral artery by-pass) by pharmacological and monitoring interventions or by maximizing oxygen delivery and inducing spinal cord hypothermia. Lumbar CSF drainage alone or in combination with other techniques remains one of the most used and effective strategies. This narrative review overviews the current techniques to prevent or avoid spinal cord injury during thoracoabdominal aortic aneurysms repair.

Cerebrospinal Fluid Diversion for Refractory Intracranial Hypertension: A United Kingdom and Ireland Survey on Practice Variation

Introduction

Diversion of cerebrospinal fluid (CSF) in a traumatic brain injury (TBI) is an established means for achieving control of intracranial pressure (ICP), aimed at improving intracranial homeostasis. The literature and anecdotal reports suggest a variation in practice between neurosurgical centres internationally, with current guidelines advocating ventricular drainage over lumbar drainage. We sought to establish the current neurosurgical practice in the United Kingdom regarding the methods of ICP control in TBI.

Methods

A 20-point survey was distributed electronically to British and Irish neurosurgeons after ratification by the Society of British Neurological Surgeons. Questions were directed at the clinician’s opinion and experience of lumbar drain usage in patients with TBI: frequency, rationale, and experience of complications. Questions on lumbar drain usage in neurovascular patients were asked for practice comparison.

Results

Thirty-six responses from 21 neurosurgical centres were returned. Twenty-three per cent (23%) of responders reported using lumbar drains for refractory ICP in TBI patients: six units use lumbar drains and 15 do not. Three units showed partial usage, with mixed “yes/no” responses between consultants. Concerns of tonsillar herniation and familiarity with EVD were commonly given reasons against the usage of lumbar drains. Fifty-six per cent (56%) reported use in neurovascular patients.

Conclusion

This contemporary practice survey demonstrates mixed practice across the UK and within some centres. Responses and survey feedback demonstrate that the use of lumbar drains in TBI is a polarising topic. The variety of practice between and within neurosurgical units supports consideration of the prospective study of CSF diversion methods for control of refractory ICP in patients with TBI.

Preoperative and postoperative complications of cerebrospinal fluid drainage in descending thoracic and thoraco-abdominal aortic aneurysm surgery: a single-center retrospective study

PURPOSE

Cerebrospinal-fluid drainage (CSFD) has been performed to prevent paraplegia in descending thoracic or thoraco-abdominal aortic aneurysm (DTA/TAAA) surgery; however, CSFD itself has a risk of severe complications. We retrospectively investigated the incidence rates of CSFD-related preoperative and postoperative complications.

METHODS

Patients who underwent DTA/TAAA surgery with a CSFD catheter that was inserted on the day before surgery were enrolled. The incidence rates of complications from spinal puncture until DTA/TAAA surgery were investigated as preoperative CSFD complications, and the incidence rates from DTA/TAAA surgery to postoperative day 7 were investigated as CSFD-related postoperative complications.

RESULTS

Preoperative CSFD complications were analyzed in 123 cases. DTA/TAAA surgery was postponed due to bloody cerebrospinal fluid (2.5%) and due to meningitis (1.7%). The incidence rate of mild preoperative complications was 32.4%. Postoperative CSFD complications were analyzed in 108 cases. Intracranial hemorrhage occurred in 3.9% of cases in open surgery and other postoperative severe CSFD complications did not occur. The incidence rates of moderate/mild complications in open surgery were 2.6%/14.3% and those in TEVAR were 3.2%/19.4%.

CONCLUSION

Bloody cerebrospinal fluid and meningitis, which are severe complications associated with spinal puncture, occurred within 1 day after spinal puncture. The incidence rates of moderate/mild complications were high in both the preoperative and postoperative periods. These results showed that CSFD catheter insertion and management should be performed carefully with consideration given to the risks and benefits of CSFD.

Safety of Cerebrospinal Fluid Drainage for Spinal Cord Ischemia Prevention in Thoracic Endovascular Aortic Repair

Objective

Spinal cord ischemia (SCI) after thoracic endovascular aortic repair (TEVAR) is associated with permanent neurologic deficit and decreased survival. Prophylactic cerebrospinal fluid (CSF) drainage (CSFD) in TEVAR is controversial. We evaluated the usage of CSFD in TEVAR at our tertiary aortic center.

Methods

Our institutional TEVAR database was reviewed to determine the frequency of CSFD usage/complications. Complications were categorized as mild (headache/CSF leak not requiring intervention, urinary retention), moderate (headache/CSF leak requiring intervention, drain malfunction requiring replacement), or severe (intrathecal hemorrhage, CSFD-attributable neurologic deficit). The relationships between CSFD complications and patient/procedural characteristics, CSFD placement timing, and survival were analyzed.

Results

Nine hundred thirty-six TEVAR procedures were performed in 869 patients from 2011 to 2020. Three hundred ninety CSFD drains were placed in 373 (41.7%) TEVAR patients. Most CSFD drains (89.5%) were pre-TEVAR. Most post-TEVAR drains were placed for new SCI symptoms (n = 21). Twenty-five patients (6.4%) suffered 32 CSFD complications. Most (n = 17) were mild in severity. Severe CSFD complications occurred in 5/432 (1.1% CSF drains) patients. No patient/procedural characteristics were predictive of CSFD complications. Post implant CSFD placement for new SCI symptoms conferred an increased risk of CSFD complication (odds ratio, 6.9; 95% CI, 2.42-19.6; P < .01). The long-term survival of the CSFD complication cohort did not differ from the overall population.

Conclusions

Post-TEVAR CSFD placement for new SCI symptoms was associated with substantially greater risk of CSFD complications. Avoidance of post-implant therapeutic drain placement might be the key to prevention of CSFD complications, favoring a strategy of selective pre-implant drain placement in patients at higher risk for SCI.

Early awaking of patients following FET allows early recognition of paraplegia with prospects for complete recovery using prompt spinal drainage

We report a patient who presented with paraplegia after ascending aorta and arch replacement using the frozen elephant trunk technique. Immediate postoperatively cerebrospinal fluid drainage allowed successful reversal of spinal cord injury. Early awakening of patients following a frozen elephant trunk technique is mandatory because it allows recognition and treatment of this complication by prompt cerebrospinal liquor drainage.

Paraplegia After Open Surgical Repair Versus Thoracic Endovascular Aortic Repair for Thoracic Aortic Disease: A Retrospective Analysis of Japanese Administrative Data

OBJECTIVES

To comparatively examine the risk of postoperative paraplegia between open surgical descending aortic repair and thoracic endovascular aortic repair (TEVAR) among patients with thoracic aortic disease.

DESIGN

Retrospective cohort study.

SETTING

Acute-care hospitals in Japan.

PARTICIPANTS

A total of 6,202 patients diagnosed with thoracic aortic disease.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The main outcome of this study was the incidence of postoperative paraplegia. Multiple logistic regression models, using inverse probability of treatment weighting and an instrumental variable (ratio of TEVAR use to open surgical repair and TEVAR uses), showed that the odds ratios of paraplegia for TEVAR (relative to open surgical descending aortic repair) were 0.81 (95% confidence interval: 0.42-1.59; p = 0.55) in the inverse probability of treatment-weighted model and 0.88 (0.42-1.86; p = 0.75) in the instrumental-variable model.

CONCLUSIONS

There were no statistical differences in the risk of paraplegia between open surgical repair and TEVAR in patients with thoracic aortic disease. Improved perioperative management for open surgical repair may have contributed to the similarly low incidence of paraplegia in these two surgery types.

Spinal Cord Protection for Thoracoabdominal Aortic Surgery

Open and endovascular repairs of the descending thoracic and thoracoabdominal aorta are associated with a substantial risk of spinal cord injury, namely paraplegia. Endovascular repairs seem to have a lower incidence of spinal cord injury, but there have been no randomized trials comparing outcomes of open and endovascular repairs. Paraplegia occurs when collateral blood supply to the anterior spinal artery is impaired. The risk of spinal cord injury can be mitigated with perioperative protocols that include drainage of cerebrospinal fluid, avoidance of hypotension and anemia, intraoperative neurophysiologic monitoring, and advanced surgical techniques. Drainage of cerebrospinal fluid using a spinal drain decreases the risk of spinal cord ischemia by improving spinal cord perfusion pressure. However, cerebrospinal fluid drainage has risks including neuraxial and intracranial bleeding, and these risks need to be carefully weighed against its potential benefit. This review discusses current surgical management of descending thoracic and thoracoabdominal aortic disease, incidence of and risk factors for spinal cord injury, and elements of spinal cord protection protocols that pertain to anesthesiologists, with a focus on cerebrospinal fluid drainage.

Acute Myelopathy: Vascular and Infectious Diseases

Vascular and infectious causes are rare but important causes of spinal cord injury. High suspicion for these processes is necessary, as symptoms may progress over hours to days, resulting in delayed presentation and diagnosis and worse outcomes. History and clinical examination findings can assist with localization of the affected vascular territory and spinal level, which will assist with focusing spinal imaging. Open and/or endovascular surgical management depends on the associated vascular abnormality. Infectious myelopathy treatment consists of targeted antimicrobial therapy when possible, infectious source control, and again, close monitoring for systemic complications.

The Evolution and Future of Spinal Drain for Thoracic Aortic Aneurysm Repair: A Review

For decades, spinal drains for cerebrospinal fluid (CSF) pressure monitoring and drainage have been used as adjuncts to protect against spinal cord injury resulting from thoracic aortic aneurysm repair. There are many different approaches to placement and management of CSF drains, with no true consensus on best practice. Furthermore, the incidence of complications resulting from spinal drains largely has been stagnant. This review describes the history and rationale behind placement of CSF drains, explore various considerations, techniques, and equipment, and discuss potential considerations for developing more comprehensive protocols.

Clinical features and outcomes after endovascular therapy for penetrating aortic ulcer and intramural hematoma

OBJECTIVES

To identify the differences between clinical features and outcomes after endovascular therapy for penetrating aortic ulcer (PAU) and intramural hematoma (IMH).

METHODS

From January 2009 to March 2020, patients who underwent endovascular therapy for PAU and IMH were enrolled. Information on patient demographics, presentation, PAU and IMH morphology, laboratory examination, and clinical follow-up information was collected and analyzed. Univariate analysis was performed to identify the differences between IMH and PAU, and Kaplan-Meier was used to calculate the cumulative survival rate and freedom from reintervention.

RESULTS

A total of 114 patients were enrolled; 80 (70.2%) of them were diagnosed with PAU. Compared with PAU, patients with IMH were younger (p = 0.006), more likely to be admitted emergently (p = 0.001), had longer hospital stay (p = 0.028), and had higher levels of C-reactive protein (p = 0.030). Meanwhile, patients with IMH were more likely to be associated with hypertension (p = 0.020) and pleural effusion (p < 0.001) and less likely to have a history of acute coronary syndrome (p = 0.019) and prior cardiovascular intervention (p = 0.017). The five-year freedom from reintervention and cumulative survival rate were 94.2% (95% confidential interval, 88.9%-99.9%) and 87.8% (95% confidential interval, 79.5%-96.9%) in PAU patients and 89.6% (95% confidential interval, 75.8%-99.9%) and 85.1% (95% confidential interval, 68.0%-99.9%) in IMH patients, respectively. There was no significant difference in freedom from reintervention (p = 0.795) or cumulative survival rate (p = 0.817).

CONCLUSIONS

IMH appeared to occur in younger patients with hypertension and usually had an acute onset, while PAU was more likely to be found incidentally in older patients with atherosclerosis. Endovascular therapy was effective in both IMH and PAU patients with encouraging outcomes.

Spinal cord protection in thoracoabdominal aortic aneurysm surgery: a multimodal approach

Spinal cord injury (SCI) is one major complication of open and endovascular thoracic and thoracoabdominal aortic aneurysm repair. Despite numerous neuroprotective adjuncts, the incidence of SCI remains high. This review article discusses established and novel adjuncts for spinal cord protection, including priming and preconditioning of the paraspinal collateral network, intraoperative systemic hypothermia, distal aortic perfusion, motor- and somatosensory evoked potentials and noninvasive cnNIRS monitoring as well as peri- and postoperative drainage of cerebrospinal fluid. Regardless of the positive influence of many of these strategies on neurologic outcome, to date no strategy assures definitive preservation of spinal cord integrity during and after aortic aneurysm repair.

Point-of-Care Thromboelastography for Intrathecal Drain Management in Patients With Coagulopathy and Thoracic Aorta Surgery: A Case Report

Spinal drain placement to prevent spinal cord ischemia during thoracic aorta surgery is a necessary yet complex undertaking in patients with coagulopathies. Thromboelastography (TEG) can be used as a point-of-care management tool to monitor coagulation status before drain placement and removal. We present 2 cases: a case of a patient with factor VII deficiency and a case of a patient with thrombocytopenia for whom TEG was an important procedural adjunct during coagulopathy reversal. TEG parameters are also discussed to encourage more frequent TEG use as an adjunct during these complex cases.

Prevention and management of spinal cord ischemia following aortic surgery: A survey of contemporary practice

OBJECTIVE

Spinal cord ischemia (SCI) is a devastating complication of thoracoabdominal aortic aneurysm repair. We aim to characterize current practices pertaining to SCI prevention and treatment across Canada.

METHODS

Two questionnaires were developed by the Canadian Thoracic Aortic Collaborative and the Canadian Cardiovascular Critical Care Society targeting aortic surgeons and intensivists. A list of experts in the management of patients at risk of SCI was developed, with representation from each of the Canadian centers that perform complex aortic surgery.

RESULTS

The response rate was 91% for both intensivists (21/23), and from cardiac and vascular surgeons (39/43). Most surgeons agreed that staging is important during endovascular repair of extent II thoracoabdominal aortic aneurysm (60%) but not for open repair (34%). All of the surgeons felt prophylactic lumbar drains were effective in reducing SCI, whereas only 66.7% of intensivists felt that lumbar drains were effective (P < .001). There was consensus among surgeons over when to employ lumbar drains. A majority of surgeons preferred to keep the hemoglobin over 100 g/L if the patient demonstrated loss of lower-extremity function, whereas most intensivists felt a target of 80 g/L was adequate (P < .001). Management of perioperative antihypertensives, use of intraoperative adjuncts, and management of venous thromboembolism prophylaxis in the presence of a lumbar drain, were highly variable.

CONCLUSIONS

We observed some consensus but considerable variability in the approach to SCI prevention and management across Canada. Future studies focused on the areas of variability may lead to more consistent and improved care for this high-risk population.

In vitro and numerical simulation of blood removal from cerebrospinal fluid: comparison of lumbar drain to Neurapheresis therapy

BACKGROUND

Blood removal from cerebrospinal fluid (CSF) in post-subarachnoid hemorrhage patients may reduce the risk of related secondary brain injury. We formulated a computational fluid dynamics (CFD) model to investigate the impact of a dual-lumen catheter-based CSF filtration system, called Neurapheresis™ therapy, on blood removal from CSF compared to lumbar drain.

METHODS

A subject-specific multiphase CFD model of CSF system-wide solute transport was constructed based on MRI measurements. The Neurapheresis catheter geometry was added to the model within the spinal subarachnoid space (SAS). Neurapheresis flow aspiration and return rate was 2.0 and 1.8 mL/min, versus 0.2 mL/min drainage for lumbar drain. Blood was modeled as a bulk fluid phase within CSF with a 10% initial tracer concentration and identical viscosity and density as CSF. Subject-specific oscillatory CSF flow was applied at the model inlet. The dura and spinal cord geometry were considered to be stationary. Spatial-temporal tracer concentration was quantified based on time-average steady-streaming velocities throughout the domain under Neurapheresis therapy and lumbar drain. To help verify CFD results, an optically clear in vitro CSF model was constructed with fluorescein used as a blood surrogate. Quantitative comparison of numerical and in vitro results was performed by linear regression of spatial-temporal tracer concentration over 24-h.

RESULTS

After 24-h, tracer concentration was reduced to 4.9% under Neurapheresis therapy compared to 6.5% under lumbar drain. Tracer clearance was most rapid between the catheter aspiration and return ports. Neurapheresis therapy was found to have a greater impact on steady-streaming compared to lumbar drain. Steady-streaming in the cranial SAS was ~ 50× smaller than in the spinal SAS for both cases. CFD results were strongly correlated with the in vitro spatial-temporal tracer concentration under Neurapheresis therapy (R² = 0.89 with + 2.13% and - 1.93% tracer concentration confidence interval).

CONCLUSION

A subject-specific CFD model of CSF system-wide solute transport was used to investigate the impact of Neurapheresis therapy on tracer removal from CSF compared to lumbar drain over a 24-h period. Neurapheresis therapy was found to substantially increase tracer clearance compared to lumbar drain. The multiphase CFD results were verified by in vitro fluorescein tracer experiments.

Surgical strategies for primary malignant tumors of the thoracic and lumbar spine

BACKGROUND

Primary malignant tumors of the thoracic and lumbar spine are rare. They are mainly hematologic malignancies and more rarely sarcomas or chordomas. Giant-cell tumors and osteoblastomas, while benign, are locally very aggressive and their excision should be discussed as an option. Other possibilities are tumors from nearby organs invading the spine, which are actually carcinomas, but may benefit from radical excision in select cases.

METHODS

Excision of these tumors is complex and must be integrated in the diagnostic and therapeutic strategy established by a specific multidisciplinary tumor board at a designated cancer center. Surgical resection must combine tumor excision with long-lasting reconstruction of the spine and neighboring soft tissues. The initial excision must be as complete as possible as the possibilities of repeat excision are nearly impossible if the first resection is not complete.

RESULTS

An exhaustive preoperative imaging workup is essential for determining the tumor's spread and for determining the best surgical strategy. This will often require participation of other surgical specialties, which are well versed in teamwork. Thanks to this multidisciplinary care, especially the participation of thoracic and plastic surgeons, significant progress has been made recently. The first is the possibility of doing very extensive tumor excisions at the spine and in the neighboring organs, thus expanding the surgical indications to patients who were previously considered as being inoperable. We will discuss the surgical strategy and surgical approaches by spine level. Bone and soft tissue reconstruction is more effective thanks to the introduction of new spinal instrumentation and coverage flaps, which have drastically reduced the intra- and postoperative complications. Lastly, the risk factors for neurological complications are better understood, making them easier to prevent and to treat, if they were to occur.

CONCLUSION

These advances have translated to better cancer outcomes, especially better control of the tumor with neoadjuvant therapies (targeted chemotherapy) and preoperative conformal radiotherapy.

Repeat Subdural Hematoma After Uncomplicated Lumbar Drain Discontinuation: A Case Report

Lumbar drains are commonly placed to monitor spinal cerebrospinal fluid (CSF) pressures and drain CSF to augment spinal cord perfusion. Excessive CSF drainage or persistent leakage through the dural puncture site can lead to cerebral hypotension and creation of an intracranial subdural hematoma. Anesthesia providers need to be aware of the risk of subdural hematoma development after major thoracoabdominal surgery where placement and subsequent removal of a lumbar drain have occurred. We present a patient who had recurrent subdural hematoma secondary to persistent undiagnosed CSF leak from the dural puncture site after uncomplicated placement and removal of a lumbar drain.

A practical guide for anesthetic management during intraoperative motor evoked potential monitoring

Postoperative motor dysfunction can develop after spinal surgery, neurosurgery and aortic surgery, in which there is a risk of injury of motor pathway. In order to prevent such devastating complication, intraoperative monitoring of motor evoked potentials (MEP) has been conducted. However, to prevent postoperative motor dysfunction, proper understanding of MEP monitoring and proper anesthetic managements are required. Especially, a variety of anesthetics and neuromuscular blocking agent are known to attenuate MEP responses. In addition to the selection of anesthetic regime to record the baseline and control MEP, the measures to keep the level of hypnosis and muscular relaxation at constant are crucial to detect the changes of MEP responses after the surgical manipulation. Once the changes of MEP are observed based on the institutional alarm criteria, multidisciplinary team members should share the results of MEP monitoring and respond to check the status of monitoring and recover the possible motor nerve injury. Prevention of MEP-related adverse effects is also important to be considered. The Working Group of Japanese Society of Anesthesiologists (JSA) developed this practical guide aimed to help ensure safe and successful surgery through appropriate anesthetic management during intraoperative MEP monitoring.

Early Outcomes After Thoracoabdominal Aortic Aneurysm Repair With Hypothermic Circulatory Arrest

BACKGROUND

A variety of intraoperative strategies are currently used for organ protection during open operations on the thoracoabdominal aorta. We report our experience with cardiopulmonary bypass and hypothermic circulatory arrest as the primary modality for organ protection, focusing on the early outcomes.

METHODS

During a 30-year interval, 285 patients underwent thoracoabdominal aortic aneurysm repair with the use of cardiopulmonary bypass with an interval of circulatory arrest (72 Crawford extent I, 107 extent II, 104 extent III, and 2 extent IV). Degenerative aneurysms were present in 72.6% and aortic dissections in 26.4% of patients. Emergent operations for rupture or acute dissection were required in 6.7% of the patients.

RESULTS

Thirty-day mortality was 7.4% and was highest for the Crawford extent II and extent III patients (10.3% and 6.7%, respectively). Permanent paralysis or paraplegia occurred in 15 patients (5.3%). The rates were highest for the extent II and extent III patients (6.5% and 6.7%, respectively). Cerebrospinal fluid drainage had no impact on the development of spinal cord injury, and implantation of intercostal/lumbar arteries had a protective effect only in patients with extent II repair. Stroke occurred in 4.2% of patients and renal failure that required dialysis occurred in 6.2%. One-year actual survival was 90.4%.

CONCLUSIONS

Our extended experience with this technique confirms its safety and effectiveness when used on a routine basis. The rates of spinal cord injury and permanent renal failure are among the lowest reported in the literature. Particularly favorable outcomes were observed in younger patients and patients undergoing elective operations.

Risk of spinal cord ischemia after thoracic endovascular aortic repair

Background

Spinal cord ischemia (SCI) is a recognized grave complication after thoracic endovascular aortic repair (TEVAR). The present study aimed to evaluate the incidence and investigate risk of SCI after TEVAR based on current prophylactic strategies designed against established risk factors.

Methods

The study retrospectively reviewed a prospectively maintained database to investigate patients who underwent TEVAR successfully between January 2009 and December 2012 in a single cardiovascular center. Detailed assessment of SCI risk was routinely performed for all patients before TEVAR was carried out. Prophylactic measures, including left subclavian artery (LSA) revascularization, blood pressure augmentation and cerebrospinal fluid (CSF) pressure control after TEVAR, were employed in high-risk patients and physical neurological examinations were regularly done to evaluate SCI after TEVAR. Patients were further divided into SCI group and non-SCI group.

Results

A total of 650 patients were enrolled in the study. Eleven patients (1.69%) developed SCI after TEVAR. Baseline level of hemoglobin was significantly lower in the SCI group (113.00 vs. 128.50, P=0.023). More patients in the SCI patients in the SCI group underwent TEVAR under general anesthesia (45.5% vs. 17.7%, P=0.033). A significantly higher incidence of post TEVAR hypotension was found in the SCI group (2.7% vs. 27.3%, P=0.004). Logistic regression analysis revealed that post-TEVAR hypotension (OR, 8.379; 95% CI, 1.833-38.304; P=0.006) was strongly associated with development of SCI and high normal baseline hemoglobin was a protective factor (OR, 0.969; CI, 0.942-0.998; P=0.037). The mortality in hospital and mortality at 1 year were not significant different between the SCI and the non-SCI group (0% vs. 1.6% P=1.000; 9.1% vs. 3.0%, P=0.294, respectively). While length of post-TEVAR stay (13.00 vs. 7.00 days, P=0.000) and length of hospital stay (20.00 vs. 13.00 days, P=0.001) were significantly greater in the SCI group.

Conclusions

Our study revealed that, based on current prophylactic measures to curtail SCI, including LSA revascularization, blood pressure augmentation and CSF pressure control after TEVAR, post-TEVAR hypotension remains a major and independent risk factor for SCI and high normal baseline hemoglobin level is protective. SCI results in longer post-TEVAR stay and hospital stay, but not associated with increased mortality. Robust precautions should be taken against underlying causes for post-TEVAR hypotension and low level of hemoglobin should be avoided.

Risk of spinal cord ischemia after fenestrated or branched endovascular repair of complex aortic aneurysms

OBJECTIVE

The aim of our study was to analyze the incidence of spinal cord ischemia (SCI) in patients presenting with complex aortic aneurysms treated with endovascular aneurysm repair (EVAR) and to identify risk factors associated with this complication.

METHODS

A retrospective study was undertaken of prospectively collected data including patients presenting with complex aortic aneurysm (pararenal abdominal aortic aneurysm and thoracoabdominal aortic aneurysm) treated with fenestrated EVAR (F-EVAR) or branched EVAR (B-EVAR). The primary end point was the incidence of SCI and the assessment of any associated factors.

RESULTS

Between January 2011 and August 2017, a total of 243 patients (mean aneurysm diameter, 65.2 ± 15.3 mm; mean age, 72.4 ± 7.5 years; 73% male) were treated with F-EVAR or B-EVAR. Asymptomatic patients were treated in 73% of the cases (177/243, in contrast to 27% urgent), and 52% (126/243) were treated for thoracoabdominal aortic aneurysm (in contrast to 48% for pararenal abdominal aortic aneurysm). F-EVAR (mean number of fenestrations, 3.3/case) and B-EVAR (mean number of branches, 3.7/case) were undertaken in 67% (164/243) and 33% (79/243), respectively. The total incidence of SCI was 17.7% [43/243; paraplegia in 4% (10/243) and paraparesis in 13.7% (33/243)]. Most of the patients with SCI presented with immediate postoperative symptoms (72% [31/43]). A spinal drain was preoperatively placed in 53% (130/243) and was associated with the prevention of SCI (SCI with spinal drainage, 12% [16/130]; SCI without spinal drainage, 24% [27/113]; P = .018). The 30-day mortality rate was 9% (21/243). After multiple logistic regression analysis, SCI was associated with preoperative renal function (SCI with preoperative glomerular filtration rate <60 mL/min/1.73 m²: odds ratio [OR], 2.43; 95% confidence interval [CI], 1.18-4.99; P = .016) and the number of vertebral segments covered (SCI with higher position of proximal stent in terms of vertebra: OR, 1.2; 95% CI, 1.1-1.3; P = .000). A similar outcome was derived when the height of the proximal end of the stent graft was replaced by the total length of aortic coverage (SCI with preoperative glomerular filtration rate <60 mL/min/1.73 m²: OR, 2.36 [95% CI, 1.11-5.00; P = .025]; SCI with longer length of aortic coverage: OR, 1.01 [95% CI, 1.003-1.009; P = .000]).

CONCLUSIONS

The majority of SCI incidence after F-EVAR or B-EVAR of complex aortic aneurysms is manifested immediately postoperatively. The use of preoperative spinal drainage may prevent SCI. Patients with GRF <60 mL/min/1.73 m² and with longer aortic stent graft coverage are at higher risk of SCI.

It Is Not Always the Epidural: A Case Report of Anterior Spinal Artery Ischemia in a Trauma Patient

Motor vehicle collisions impact millions of people annually resulting in multiinjury trauma. Anesthesiologists are consulted for rib fracture analgesia to improve respiratory mechanics and prevent intubation. This report describes a trauma patient who developed hypotension and lower extremity weakness after epidural placement for multiple rib fractures. Initially, hypotension was attributed to neuraxial sympathectomy. However, physical examination also indicated anterior spinal artery ischemia. Regional anesthesia and acute pain teams must be able to both identify contraindications and complications of regional techniques and discern when complications are not a result of regional interventions to initiate prompt management and definitive care.

Outcomes of Stentless Thoracic Endovascular Aortic Repair for Chronic DeBakey IIIb Aneurysms

BACKGROUND

We introduce a new endovascular procedure for favorable aortic remodeling in patients with chronic DeBakey IIIb (CDIIIb) aneurysms and present outcomes.

METHODS

This study included 19 patients who underwent stentless thoracic endovascular aortic repair (TEVAR) for CDIIIb aneurysms between 2014 and 2016. Stentless TEVAR is defined as an endovascular procedure involving closure of communicating channels or obliteration of the false lumen itself using various materials. Thoracic false lumen thrombosis was defined as there was no flow in the false lumen of the thoracic aorta. Aortic diameter was measured at 3 levels (left subclavian artery, pulmonary artery bifurcation, and celiac axis).

RESULTS

Fifteen of 19 (78.9%) patients demonstrated thoracic false lumen thrombosis. There was no mortality, and the mean follow-up duration was 16.8 months. False and true lumen diameters at the left subclavian and pulmonary artery levels significantly changed after the procedure (false lumen: 22.6 ± 16.6 versus 16.1 ± 14.4 mm, 23.2 ± 14.6 versus 18.0 ± 13.2 mm, p = 0.001 and p = 0.002, respectively; true lumen: 22.7 ± 8.7 versus 27.9 ± 6.3 mm, 19.0 ± 8.3 versus 24.3 ± 6.7 mm, p = 0.001 and p = 0.001, respectively). The number of visceral stent grafts and preoperative true lumen diameter at the pulmonary artery were independent predictors for thoracic false lumen thrombosis (hazard ratio, 3.445, 95% confidence interval, 1.494 to 7.946; p = 0.004; and hazard ratio, 1.106; 95% confidence interval, 1.029 to 1.189; p = 0.006, respectively).

CONCLUSIONS

Stentless TEVAR seems to be a safe procedure and enables favorable aortic remodeling. Thus, this technique can be useful in a selected group of patients with CDIIIb aneurysms.

Spinal cord protection in aortic endovascular surgery

A persistent neurological deficit, such as paraplegia or paraparesis, secondary to spinal cord injury remains one of the most feared complications of surgery on the descending thoracic or abdominal aorta. This is despite sophisticated advances in imaging and the use of less invasive endovascular procedures. Extensive fenestrated endovascular aortic graft prostheses still carry a risk of spinal cord injury of up to 10%; thus, this risk should be identified and strategies implemented to protect the spinal cord and maintain perfusion. The patients at highest risk are those undergoing extensive thoracic aortic stenting including thoracic, abdominal, and pelvic vessels. Although many techniques are available, lumbar cerebrospinal fluid drainage remains the most frequent intervention, along with maintenance of perfusion pressure and possibly staged procedures to allow collateral vessel stabilization. Many questions remain regarding other technical aspects, spinal cord monitoring and cooling, pharmacological protection, and the optimal duration of interventions into the postoperative period.

A Seizure and Hemiplegia following Contrast Exposure: Understanding Contrast-Induced Encephalopathy

Contrast-induced encephalopathy is a rare, reversible phenomenon known to occur after intravenous or intra-arterial contrast exposure. This report describes a case involving a 73-year-old female admitted for an elective thoracic aortic aneurysm repair. During the procedure, a large volume of nonionic iodinated contrast was necessary for arteriography. Postoperatively, the patient developed seizure activity followed by left-sided hemiplegia. Computed tomography (CT) of the brain without contrast and magnetic resonance imaging (MRI) were negative for acute stroke but did show residual contrast surrounding the brain. Antiepileptic medications were administered with resolution of the seizure activity. The patient was treated with supportive management and improved to baseline over the next seven days. This case demonstrates a rare, nonionic iodinated contrast-induced encephalopathy with seizure activity and transient hemiplegia. The unique imaging findings differentiate it from other neurologic conditions.

Cerebrospinal fluid drains reduce risk of spinal cord injury for thoracic/thoracoabdominal aneurysm surgery: A review

Background

The risk of spinal cord injury (SCI) due to decreased cord perfusion following thoracic/thoracoabdominal aneurysm surgery (T/TL-AAA) and thoracic endovascular aneurysm repair (TEVAR) ranges up to 20%. For decades, therefore, many vascular surgeons have utilized cerebrospinal fluid drainage (CSFD) to decrease intraspinal pressure and increase blood flow to the spinal cord, thus reducing the risk of SCI/ischemia.

Methods

Multiple studies previously recommend utilizing CSFD following T/TL-AAA/TEVAR surgery to treat SCI by increasing spinal cord blood flow. Now, however, CSFD (keeping lumbar pressures at 5-12 mmHg) is largely utilized prophylactically/preoperatively to avert SCI along with other modalities; avoiding hypotension (mean arterial pressures >80-90 mmHG), inducing hypothermia, utilizing left heart bypass, and employing intraoperative neural monitoring [somatosensory (SEP) or motor evoked (MEP) potentials]. In addition, preoperative magnetic resonance angiography (MRA) and computed tomographic angiography (CTA) scans identify the artery of Adamkiewicz to determine its location, and when/whether reimplantation/reattachment of this critical artery and or other major segmental/lumbar arterial feeders are warranted.

Results

Utilizing CSFD for 15-72 postoperative hours in T/TL-AAA/TEVAR surgery has reduced the risks of SCI from a maximum of 20% to a minimum of 2.3%. The major complications of CSFD include; spinal and cranial epidural/subdural hematomas, VI nerve palsies, retained catheters, meningitis/infection, and spinal headaches.

Conclusions

By increasing blood flow to the spinal cord during/after T/TL-AAA/TEVAR surgery, CSFD reduces the incidence of permanent SCI from, up to 10-20% down to down to 2.3-10%. Nevertheless, major complications, including spinal/cranial subdural hematomas, still occur.