Risk factors for spinal cord injury and complications of cerebrospinal fluid drainage in patients undergoing fenestrated and branched endovascular aneurysm repair

Objective: Spinal cord injury (SCI) is one of the most devastating complications of thoracoabdominal aortic aneurysm (TAAA) repair. Cerebrospinal fluid drainage (CSFD) is routinely used to prevent and to treat SCI during open TAAA repair. However, the risks and benefits of CSFD during fenestrated-branched endovascular aneurysm repair (F/B-EVAR) are unclear. This study aimed to determine the risk of SCI after F/B-EVAR and to assess the risks and benefits of CSFD. Methods: We analyzed 106 consecutive patients with TAAAs treated with F/B-EVAR from 2014 to 2019 in a prospective physician-sponsored investigational device exemption study (G130193). Data were collected prospectively and audited by an independent external monitor. All patients were treated with Cook manufactured patient-specific F/B-EVAR devices or the Cook t-Branch devices (Cook Medical, Bloomington, Ind). CSFD was used at the discretion of the principal investigator. Risk factors for SCI were identified, and CSFD complications were assessed. Results: Prophylactic CSFD was used in 78 patients (73.6%), and 28 patients (26.4%) underwent F/B-EVAR without CSFD. Four patients (3.8%) with prophylactic CSFD developed SCI, including two patients (1.9%) with permanent paraplegia (Tarlov grade 1-2) and two patients (1.9%) with paraparesis (Tarlov grade 3). Multivariate analysis revealed that greater extent of thoracic aortic coverage (odds ratio, 1.06; 95% confidence interval, 1.00-1.11; P = .02) and intraoperative blood loss (odds ratio, 1.00; 95% confidence interval, 1.00-1.002; P = .04) were the significant risk factors for SCI. Six patients (7.6% [6/78]) experienced major CSFD-related complications, including subarachnoid hemorrhage in 2.6% (2), spinal hematoma in 2.6% (2), cerebellar hemorrhage in 1.3% (1), and spinal drain fracture requiring surgical laminectomy in 1.3% (1). Minor CSFD-related complications occurred in 20 patients (25.6% [20/78]), including paresthesia during CSFD insertion (10), minimal bloody cerebrospinal fluid (7), drain malfunction (2), and reflex hypotension (1). Technical difficulties during CSFD catheter placement were noted in seven patients (9.0%). Excluding four patients with SCI, intensive care unit stay was 3.3 +/- 4.0 days in the CSFD group vs 1.2 +/- 0.9 days in the no-CSFD group (P = .007). Total hospital length of stay was 6.0 +/- 4.9 days in the CSFD group vs 3.5 +/- 1.9 days in the no-CSFD group (P = .01). Conclusions: The incidence of SCI after F/B-EVAR with selective CSFD was low, and risk factors for SCI were greater with extent of thoracic aortic coverage and intraoperative blood loss. However, the incidence of major CSFD-related complications exceeded the incidence of SCI, and CSFD significantly increased both intensive care unit and total hospital length of stay. Therefore, routine prophylactic CSFD may not be justified, and a prospective randomized trial of CSFD in patients undergoing F/B-EVAR seems appropriate.