Prospective randomized pilot trial comparing prophylactic and therapeutic cerebrospinal fluid drainage during complex endovascular thoracoabdominal aortic aneurysm repair.

BACKGROUND: Endovascular techniques have transformed the management of thoracoabdominal aortic aneurysms (TAAAs). However, spinal cord ischemia (SCI) remains a prevalent and devastating complication. Prophylactic drainage of cerebrospinal fluid (CSF) is among the proposed strategies for prevention of SCI. Although prophylactic CSF drainage is widely used and conceptually attractive, prophylactic CSF drains have not been demonstrated to definitively prevent the occurrence nor mitigate the severity of SCI in endovascular TAAA repair. Whether or not outcomes of prophylactic drains are superior to therapeutic drains remains unknown. This pilot study was performed to determine the feasibility of a randomized clinical trial designed to investigate the role of prophylactic vs therapeutic CSF drains in the prevention of SCI in patients undergoing endovascular TAAA repair using branched and fenestrated endovascular aortic repair (FBEVAR). METHODS: This was a prospective multicenter randomized pilot clinical trial conducted at The University of Alabama at Birmingham and The University of Massachusetts. Twenty patients were enrolled and randomized to either the prophylactic drainage or therapeutic drainage groups, prior to undergoing FBEVAR for extensive TAAAs and arch aortic aneurysms. This was a pilot feasibility study that was not powered to detect statistical differences in clinical outcomes. The primary outcome was feasibility of randomization and compliance with a shared lumbar drain protocol. Secondary outcomes included rate of drain complications and SCI. RESULTS: Twenty patients were enrolled and successfully randomized, without any crossovers, to either the control cohort (n = 10), without prophylactic drains, or the experimental cohort (n = 10), with prophylactic drains. There were no differences in age, comorbidities, or history of prior aortic surgery across the cohorts. All patients were treated with FBEVAR. Aneurysm classifications were as follows: Extent I (10%), Extent II (50%), Extent III (35%), and Extent IV (5%). The average length of aortic coverage was 207 ± 21.6 mm. The length of aortic coverage did not vary across cohorts, nor did procedural times or blood loss volume. Compliance with the SCI prevention protocol was 100% across both groups. Within the prophylactic drain cohort, one patient experienced an adverse event related to lumbar drain placement, manifested as an epidural hematoma requiring laminectomy, without neurologic deficit (n = 1/10; 10%). There was one SCI event (n = 1/20; 5%), which occurred in the prophylactic drain cohort on postoperative day 9 following an episode of hypotension related to a gastrointestinal bleed. CONCLUSIONS: The role of prophylactic CSF drains for the prevention of SCI following endovascular TAAA repair is a topic of ongoing research, with many current practices based on expert opinion and experience, rather than rigorous scientific data. This study demonstrates the feasibility of a multicenter randomized clinical trial to evaluate the role of prophylactic vs therapeutic CSF drains in the prevention of SCI in patients undergoing endovascular TAAA repair.

Predictors and outcomes of spinal cord injury following complex branched/fenestrated endovascular aortic repair in the US Aortic Research Consortium.

OBJECTIVE: Spinal cord ischemia (SCI) is a well-known complication of thoracoabdominal aortic aneurysm repair and is associated with profound morbidity and mortality. The purpose of this study was to describe predictors for the development of SCI, as well as outcomes for patients who develop SCI, after branched/fenestrated endovascular aortic repair in a large cohort of centers with adjudicated physician-sponsored investigational device exemption studies. METHODS: We used a pooled dataset from nine US Aortic Research Consortium centers involved in investigational device exemption trials for treatment of suprarenal and thoracoabdominal aortic aneurysms. SCI was defined as new transient weakness (paraparesis) or permanent paraplegia after repair without other potential neurological etiologies. Multivariable analysis was performed to identify predictors of SCI, and life-table analysis and Kaplan-Meier methodologies were used to evaluate survival differences. RESULTS: A total of 1681 patients underwent branched/fenestrated endovascular aortic repair from 2005 to 2020. The overall rate of SCI was 7.1% (3.0% transient and 4.1% permanent). Predictors of SCI on multivariable analysis were Crawford Extent I, II, and III distribution of aortic disease (odds ratio [OR], 4.79; 95% confidence interval [CI], 4.77-4.81; P < .001), age ≥70 years (OR, 1.64; 95% CI, 1.63-1.64; P = .029), packed red blood cell transfusion (OR, 2.00; 95% CI, 1.99-2.00; P = .001), and a history of peripheral vascular disease (OR, 1.65; 95% CI, 1.64-1.65; P = .034). The median survival was significantly worse for patients with any degree of SCI compared with those without SCI (any SCI, 40.4 vs no SCI, 60.3 months; log-rank P < .001), and also worse in those with a permanent deficit (24.1 months) vs those with a transient deficit (62.4 months) (log-rank P < .001). The 1-year survival for patients who developed no SCI was 90.8%, compared with 73.9% in patients who developed any SCI. When stratified by degree of deficit, survival was 84.8% at 1 year for those who developed paraparesis and 66.2% for those who developed permanent deficits. CONCLUSIONS: The overall rates of any SCI at 7.1% and permanent deficit at 4.1% observed in this study compare favorably with those reported in contemporary literature. Our findings confirm that increased length of aortic disease is associated with SCI and those with Crawford Extent I to III thoracoabdominal aortic aneurysms are at highest risk. The long-term impact on patient mortality underscores the importance of preventive measures and rapid implementation of rescue protocols if and when deficits develop.