A report of the safety of prophylactic spinal fluid drainage in open and endovascular thoracic and thoracoabdominal aortic aneurysm patients.

Abstract

Spinal cord injury (SCI) is a complication of open and endovascular thoracic aortic aneurysm (TAA) and thoracoabdominal aortic aneurysm (TAAA) repair. Spinal fluid drainage (SFD) is used to reduce SCI risk in open surgery; however, many question the safety of SFD in endovascular repair. The objective of this retrospective study was to review the risks of prophylactic SFD in 1445 patients undergoing open and endovascular TAA and TAAA repair from 1987 to 2023. Spinal drains were placed in open TAAA repairs and endovascular repairs planning >12 cm aortic coverage. Cardiac anesthesiologists placed and managed all drains. From 2000 to 2023, spinal drains for elective surgery were placed using fluoroscopic guidance. SF was drained to <5 to 8 mm Hg depending on SCI risk. If bloody fluid appeared, drainage was stopped and a computed tomography (CT) can of the head was obtained. Drainage was stopped when patient demonstrated normal leg strength; drains were removed at 48 hours if leg strength was normal. A post-SFD headache was treated with a blood patch. We tracked intraoperative fluid drained, neurological complications from SFD (any neurological deficit from intracranial or spinal hematoma), bloody SF, intracranial blood on head CT without neurological deficit, headache requiring blood patch, transient SCI (paraparesis/paraplegia), and permanent SCI (paraparesis/paraplegia). Of the 1445 patients (1029 open, 416 endovascular) undergoing TAA/TAAA repair, 1007 (777 open, 230 endovascular) had SFD. Before 2000, 263 open repairs done with smaller drains had an average of 125 mL of fluid drained intraoperatively to achieve pressure goals. From 2000 to 2023, intraoperative SFD to achieve pressure goals averaged 132 mL in open and 81 mL in endovascular repairs. Six patients (0.6%) had neurological complications from SFD; five of these (0.77%) occurred in open patients. Only one patient undergoing endovascular repair had a neurological complication from SFD (0.43%). From 2000 to 2023, other events not resulting in neurological deficit included bloody SF (20.7% open; 21.7% endovascular), intracranial blood on CT without neurological deficit (9.9% open; 6.1% endovascular), and headache requiring blood patch (7.6% open; 11.7% endovascular). From 2000 to 2023, 5.6% of open patients had transient SCI, 4.2% had permanent SCI. 3.6% of endovascular patients had transient SCI, and 1.2% had permanent SCI. Prophylactic SFD can be performed with acceptable risk in both endovascular and open TAAA repairs. We advocate that prophylactic SFD be used to reduce risk of SCI in both endovascular and open TAAA repairs.