Spinal cord monitoring using collateral network near-infrared spectroscopy during extended aortic arch surgery with a frozen elephant trunk

The true incidence of spinal cord injury associated with modern hybrid extended arch/descending aortic procedures utilizing a frozen elephant trunk (fET) remains unclear, and it is estimated with ~5-8%. Prolonged distal arrest without sufficient hypothermic protection as well as extended coverage of segmental arteries have been suggested to cause this complication, previously uncommon in open arch surgery. Recently, extensive clinical and experimental research led to the implementation of a new method of collateral network near-infrared spectroscopy (cnNIRS) to non-invasively monitor spinal cord oxygenation in the setting of extensive thoracoabdominal aortic repair. To date, limited experience with this method during arch procedures exists. Based on recent experiments regarding the optimal cnNIRS optode placement, we used this method for the first time during an fET procedure to document mid-thoracic paraspinous oxygenation levels.