Outcomes of a Spinal Drain and Intraoperative Neurophysiologic Monitoring Protocol in Thoracic Endovascular Aortic Repair

Systematic Review of the Effect of Cerebrospinal Fluid Drainage on Outcomes After Endovascular Descending Thoracic/Thoraco-Abdominal Aortic Aneurysm Repair

OBJECTIVE

This study aimed to investigate whether prophylactic use of cerebrospinal fluid (CSF) drainage in endovascular descending thoracic aortic aneurysm (DTAA) and thoraco-abdominal aortic aneurysm (TAAA) repair contributes to a lower rate of post-operative spinal cord ischaemia (SCI).

DATA SOURCES

MEDLINE, Embase, and CINAHL.

REVIEW METHODS

A literature review was conducted in accordance with PRISMA guidelines (PROSPERO registration no. CRD42021245893). Risk of bias was assessed through the Newcastle-Ottawa scale (NOS), and the certainty of evidence was graded using the GRADE approach. A proportion meta-analysis was conducted to calculate the pooled rate and 95% confidence interval (CI) of both early and late onset SCI. Pooled outcome estimates were calculated using the odds ratio (OR) and associated 95% CI. The primary outcome was SCI, both early and lateonset. Secondary outcomes were complications of CSF drainage, length of hospital stay, and peri-operative (30 day or in hospital) mortality rates.

RESULTS

Twenty-eight observational, retrospective studies were included, reporting 4 814 patients (2 599 patients with and 2 215 without CSF drainage). The NOS showed a moderate risk of bias. The incidence of SCI was similar in patients with CSF drainage (0.05, 95% CI 0.03 ‒ 0.08) and without CSF drainage (0.05, 95% CI 0.00 ‒ 0.14). No significant decrease in SCI was found when using CSF drainage (OR 0.67, 95% CI 0.29 ‒ 1.55, p = .35). The incidence rate of CSF drainage related complication was 0.10 (95% CI 0.04 ‒ 0.19). The 30 day and in hospital mortality rate with CSF drainage was 0.08 (95% CI 0.05 ‒ 0.12). The 30 day and in hospital mortality rate without CSF drainage and comparison with late mortality and length of hospital stay could not be determined due to lack of data. The quality of evidence was considered very low.

CONCLUSION

Pre-operative CSF drainage placement was not related to a favourable outcome regarding SCI rate in endovascular TAAA and DTAA repair. Due to the low quality of evidence, no clear recommendation on pre-operative use of CSF drainage placement can be made.

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.

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.

A Systematic Review of Spinal Cord Ischemia Prevention and Management After Open and Endovascular Aortic Repair

OBJECTIVE

Spinal cord ischemia (SCI) is one of the most devastating complications after descending thoracic aortic (DTA) and thoracoabdominal aortic (TAA) repairs. Patients who develop SCI have a poor prognosis with mortality rates reaching 75% within the first year after surgery. Many factors have been shown to increase the risk of this complication, including extent of TAA repair, length of aortic and collateral network coverage, embolization, and reduced spinal cord perfusion pressure. As a result, a variety of treatment strategies have evolved. We aimed to provide an up-to-date review of SCI rates with associated treatment algorithms from open and endovascular DTA and TAA repairs.

METHODS

Using PRISMA guidelines, a literature review with the Medical Subject Headings (MeSH) terms "spinal cord ischemia; spinal cord ischemia prevention and mitigation strategies; spinal cord ischemia rates; spinal cord infarction" was performed in the Cochrane and PubMed databases to seek all peer-reviewed studies of DTA and TAA repairs with SCI complications, limited to 2012-2021 and the English language. MeSH subheadings including diagnosis, complications, physiopathology, surgery, mortality, and therapy were used to further restrict the articles. Studies were excluded if they were not in humans, not pertaining to SCI in DTA/TAA operative repairs, and if the study primarily discussed neuromonitoring techniques. Additionally, studies with <40 patients or limited information regarding SCI protection strategies were excluded. Each study was individually reviewed by two researchers to assess for type and extent of aortic pathology, operative technique, SCI protection or mitigation strategies, rates of overall and permanent SCI symptoms, associations with SCI on multivariate analysis, and mortality.

RESULTS

Of 450 studies returned by the MeSH search strategy, 41 met inclusion criteria and were included in the final analysis. For endovascular DTA repair patients, overall SCI rates ranged from 0-10.6% with permanent SCI symptoms ranging from 0-5.1%. Endovascular and open TAA repairs had rates of overall SCI of 0-35%. Permanent SCI symptom rate was reported by only one open study at 1.1% while endovascular TAA repairs had between 2-20.5%.

CONCLUSION

This review provides an up-to-date review of current rates of SCI as well as prevention and mitigation strategies for DTA and TAA repairs. We find that a multimodal approach, including a bundled institutional protocol, staging of multiple repairs, preservation of collateral blood flow network, augmented spinal cord perfusion, selective cerebrospinal fluid drainage, and distal aortic perfusion in open TAA repairs, appears to be important in reducing the risk of SCI.

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.

Staged total arch replacement, followed by fenestrated-branched endovascular aortic repair, for patients with mega aortic syndrome

OBJECTIVE

The aim of the present study was to review the clinical outcomes of a staged approach using total arch replacement (TAR) with an elephant trunk or a frozen elephant trunk, followed by fenestrated-branched endovascular aortic repair (F-BEVAR) for patients with mega aortic syndrome.

METHODS

We reviewed the clinical data and outcomes of 11 consecutive patients (8 men; mean age, 71 ± 7 years) treated by staged TAR and F-BEVAR from January 2014 to December 2018. The F-BEVAR procedures were performed under a prospective, nonrandomized, physician-sponsored investigational device exemption protocol. All patients had had mega aortic syndrome, defined by an ascending aorta, arch, and extent I-II thoracoabdominal aortic aneurysm. The endpoints were 30-day mortality, major adverse events (MAE), patient survival, freedom from reintervention, and freedom from target vessel instability.

RESULTS

Of the 11 patients, 6 had developed chronic postdissection aneurysms after previous Stanford A (three A₁₁, two A₁₀, one A₉) dissection repair and 5 had had degenerative aneurysms with no suitable landing zone in the aortic arch. The thoracoabdominal aortic aneurysms were classified as extent I in four patients and extent II in seven. One patient had died within 30 days after TAR (9.0%). However, none of the remaining 10 patients who had undergone F-BEVAR had died. First-stage TAR resulted in MAE in three patients (27%), including one spinal cord injury. The mean length of stay was 12 ± 6 days. The mean interval between TAR and F-BEVAR was 245 ± 138 days with no aneurysm rupture during the interval. Second-stage F-BEVAR was associated with MAE in two patients (20%), including spinal cord injury in one patient from spinal hematoma due to placement of a cerebrospinal fluid drain. The mean follow-up period was 14 ± 10 months. At 2 years postoperatively, patient survival, primary patency, secondary patency, and freedom from renal-mesenteric target vessel instability was 80% ± 9%, 94% ± 6%, 100%, and 86% ± 8%, respectively. No aortic-related deaths occurred during the follow-up period. Four patients had required reintervention, all performed using an endovascular approach.

CONCLUSIONS

A staged approach to treatment of mega aortic syndrome using TAR and F-BEVAR is a feasible alternative for selected high-risk patients. Larger clinical experience and longer follow-up are needed.

Complications associated with lumbar drain placement for endovascular aortic repair

OBJECTIVE

We reviewed the complications associated with perioperative lumbar drain (LD) placement for endovascular aortic repair.

METHODS

Patients who had undergone perioperative LD placement for endovascular repair of thoracic and thoracoabdominal aortic pathologies from 2010 to 2019 were reviewed. The primary endpoints were major and minor LD-associated complications. Complications that had resulted in neurological sequelae or had required an intervention or a delay in operation were defined as major. These included intracranial hemorrhage, symptomatic spinal hematoma, cerebrospinal fluid (CSF) leak requiring intervention, meningitis, retained catheter tip, arachnoiditis, and traumatic (or bloody) tap resulting in delayed operation. Minor complications were defined as a bloody tap without a delay in surgery, asymptomatic epidural hematoma, and CSF leak with no intervention required. Isolated headaches were recorded separately owing to the minimal clinical impact.

RESULTS

A total of 309 LDs had been placed in 268 consecutive patients for 222 thoracic endovascular aortic repairs, 85 complex endovascular aortic repairs (EVARs; fenestrated branched EVAR/parallel grafting), and 2 EVARs (age, 65 ± 13 years; 71% male) for aortic pathology, including aneurysm (47%), dissection (49%), penetrating aortic ulcer (3%), and traumatic injury (0.6%). A dedicated neurosurgical team performed all LD procedures; most were performed by the same individual, with a technical success rate of 98%. Radiologic guidance was required in 3%. The reasons for unsuccessful placement were body habitus (n = 2) and severe spinal disease (n = 3). Most were placed prophylactically (96%). The overall complication rate was 8.1% (4.2% major and 3.9% minor). Major complications included spinal hematoma with paraplegia in 1 patient, intracranial hemorrhage in 2, meningitis in 2, arachnoiditis in 3, CSF leak requiring a blood patch in 3, bloody tap delaying the operation in 1, and a retained catheter tip in 1 patient. Patients who had undergone previous LD placement had experienced significantly more major LD-related complications (12.2% vs 3%; P = .019). The rate of total LD-associated complications did not differ between prophylactic and emergent therapeutic placements (8.1% vs 7.7%; P = 1.00) nor between major or minor complications. On multivariate analysis, previous LD placement and an overweight body mass index were the only independent predictors of major LD-related complications.

CONCLUSIONS

The complications associated with LD placement can be severe even when performed by a dedicated team. Previous LD placement and overweight body mass index were associated with a significantly greater risk of complications; however, emergent therapeutic placement was not. Although these risks are justified for therapeutic LD placement, the benefit of prophylactic LD placement to prevent paraplegia should be weighed against these serious complications.

Aneurysms and dissections - What is new in the literature of 2019/2020 - a European Society of Vascular Medicine annual review

More than 6,000 publications were found in PubMed concerning aneurysms and dissections, including those Epub ahead of print in 2019, printed in 2020. Among those publications 327 were selected and considered of particular interest.

Permissive Hypertension and Collateral Revascularization May Allow Avoidance of Cerebrospinal Fluid Drainage in Thoracic Endovascular Aortic Repair

BACKGROUND

The utility of cerebrospinal fluid drainage (CSFD) for prevention of spinal cord ischemia (SCI) after thoracic endovascular aortic repair (TEVAR) remains unclear. We previously published our institutional algorithm restricting preoperative CSFD to patients deemed high risk for SCI. Since that publication, our algorithm has evolved with preoperative CSFD avoided in all patients undergoing isolated descending TEVAR with or without arch involvement (+/- arch TEVAR). This study evaluated the updated algorithm in a contemporary cohort.

METHODS

Patients who underwent TEVAR for descending aortic +/-arch pathology between February 2012 and September 2018 at a single center were identified from an institutional aortic surgery database. The algorithm includes left subclavian artery (LSA) revascularization in cases of coverage with no preservation of antegrade flow, permissive hypertension, and use of evoked potential monitoring. The primary end points were SCI or postoperative CSFD.

RESULTS

During the study interval, 225 patients underwent descending +/- arch TEVAR. CSFD was used before TEVAR in 2 patients (0.9%) in violation of the algorithm, and they were excluded from the study cohort. Endograft coverage below T6 occurred in 81%. The LSA was fully covered in 100 patients (47%), all of whom underwent LSA revascularization. Following the updated algorithm, the incidence of temporary or permanent SCI was 0%. No patient required postoperative CSFD.

CONCLUSIONS

A restrictive lumbar CSFD algorithm, including permissive hypertension and LSA revascularization in the setting of descending +/- arch TEVAR, appears safe, with a 0% incidence of SCI in 223 consecutive patients treated during a 6.5-year interval. We recommend consideration of further prospective study to evaluate this algorithm.