Correlation Between Intraoperative Near-infrared Spectroscopy Values and Neurologic Outcomes in Patients Undergoing Total Aortic Arch Replacement Using the Frozen Elephant Trunk Technique.

OBJECTIVE

To correlate intraoperative near-infrared spectroscopy (NIRS) values with neurologic outcomes in patients undergoing total aortic arch replacement using the frozen elephant trunk (FET) technique.

DESIGN

Retrospective, single-center registry study using a two-way repeated-measures analysis of variance.

SETTING

Between November 2013 and December 2023, 427 patients were treated for acute and chronic aortic pathologies using the FET procedure.

PARTICIPANTS

A total of 166 patients with complete NIRS data at all predefined time points were included and retrospectively divided into two groups: patients diagnosed by experienced radiologists and clinicians with stroke and without stroke after FET.

MEASUREMENTS: Bilateral NIRS values were recorded continuously and at seven critical time points in each patient, and correlations were made between left- and right-sided NIRS values and stroke.

MAIN

RESULTS

A total of 23 patients (13.9%) were diagnosed with stroke. There was a significantly higher in-hospital mortality in patients with stroke (21.7%) compared with patients without stroke (7.7%, p = 0.037). Left-sided regional cerebral oxygenation did not show significant difference in patients with versus without stroke (p = 0.550). Differences were detected in right-sided regional cerebral oxygenation trends (p < 0.001) and interhemisphere NIRS at specified time points (p = 0.009). The interaction, time × stroke, however, did not show significant results in any analysis (p > 0.05).

CONCLUSION

NIRS is a reliable tool to monitor intraoperative frontal lobe cerebral oxygen saturation. However, its use to predict postoperative stroke remains limited. Further refinements are needed to develop the technique into a prediction tool.