Near-Infrared Spectroscopy for Monitoring Spinal Cord Ischemia During Hybrid Thoracoabdominal Aortic Aneurysm Repair

Abstract

Purpose:

To describe a simple, noninvasive technique to detect changes in oxygen saturation at the level of the spinal cord and to suggest its suitability for individualized blood pressure management during and after thoracoabdominal aneurysm repair.

Case Report:

A 53-year-old man with a history of multiple arch and thoracic aortic procedures underwent staged hybrid treatment of a large TAAA due to chronic dissection from the distal aortic arch into the iliac arteries. During the procedures, near-infrared spectroscopy (NIRS) sensors were applied over the 10th thoracic vertebra for continuous monitoring of tissue oxygen saturation (S_sO₂) during endovascular repair. After stent-graft deployment, mean S_sO₂ decreased significantly. Moreover, the relationship between S_sO₂ and arterial blood pressure became linear, reflecting pressure dependency of spinal cord perfusion after stent deployment. Conclusion: These data show that NIRS monitors post-endograft changes in S_sO₂ that were strongly related to arterial blood pressure. Regional NIRS monitoring at the vertebral level may function as a valuable noninvasive guide to the management of blood pressure during thoracoabdominal aneurysm repair, both intra- and postoperatively.