TAA 6. Staging Procedures, Cerebrospinal Fluid Drainage, Selective Neuromonitoring, and Use of Conduits During Complex Endovascular Aortic Repair in Patients With High Risk of Spinal Cord Injury

Abstract

Spinal cord ischemia (SCI) after thoracic endovascular aortic repair (TEVAR) and thoracoabdominal aortic aneurysm (TAAA) repair is a devastating complication. Outcomes improved significantly after 2015, when we revised our spinal cord protection strategy. This study describes a single experience of SCI prevention in patients who have had endovascular repair. A prospectively maintained database of patients having repair using standard, branched/fenestrated stent grafts at a single university center was reviewed. We optimized the implantation procedure, including the early restoration of pelvic and lower limb perfusion by precannulated devices and temporal conduits. The left subclavian artery was routinely revascularized before coverage. Procedures for extent thoracic and II and III TAAAs were staged. The aim was also to maintain controlled perfusion to the sac before complete exclusion. In cases of TEVAR, the first step was subclavian revascularization, then endograft deployment, and the next step was proximal occlusion of the left subclavian artery with a plug. For the TAAA, strategies used for staging included placement of the thoracic component; branch/fenestration device deployment, maintaining perfusion to the sac by delayed completion of either one of the stent graft side branches, perfusion branches, or contralateral iliac limb extension; and complete exclusion after side branch occlusion test and motor and somatosensory evoked potential monitoring (Fig). The current policy was to place a spinal drain; the mean arterial pressure is raised to >90 to 100 mm Hg, and the hemoglobin level is maintained at 10 g/dL. Twenty-nine patients (median age, 73 years; 24 male patients; 20 TEVARs and 9 branched/fenestrated endovascular aneurysm repairs) underwent endovascular repair. No death or neurologic symptoms or signs related to SCI were registered at 30 days. Temporary iliofemoral conduits were used in 16 limbs in 14 patients. One patient had a ≥75% decrease in motor and somatosensory evoked potential amplitude, and the complete exclusion of the sac was delayed for 2 more weeks. No patients developed late SCI or mortality. This series illustrates the importance of a dedicated institutional protocol aimed at ensuring the intraoperative maneuvers to avoid perioperative paraplegia. This study aimed to demonstrate the possible protective effects of ischemic preconditioning on the preservation of spinal cord function after segmental and sequential artery occlusion.