Multimodal neuromonitoring-guided cerebral protection and early neurocognitive outcomes after aortic arch surgery

Open aortic arch surgery exposes patients to hypothermic circulatory arrest, selective antegrade cerebral perfusion, rewarming, and arch-vessel manipulation. Postoperative delirium and early cognitive decline remain clinically important complications. Because single-modality cerebral oximetry cannot fully capture perioperative cerebral physiological burden, this study evaluated whether a multimodal neuromonitoring-guided cerebral-protection protocol was associated with lower cerebral physiological burden and improved early neurocognitive outcomes after aortic arch surgery.

This retrospective single-center cohort study screened consecutive adult patients who underwent open aortic arch surgery from January 1, 2021 to April 30, 2026. Patients treated from January 1, 2021 to December 31, 2023 formed the conventional cerebral-protection cohort, and patients treated from January 1, 2024 to April 30, 2026 formed the multimodal-guided cohort. The guided protocol used bilateral near-infrared spectroscopy, processed electroencephalography, transcranial Doppler, and cerebral oximetry index-derived autoregulation monitoring to trigger correction of perfusion pressure, selective antegrade cerebral perfusion flow, cannula position, PaCO₂, hemoglobin, anesthetic depth, and rewarming speed. The primary outcome was postoperative delirium within postoperative days 1-5. The main secondary cognitive outcome was MoCA-defined 30-day cognitive decline. Inverse probability weighting and multivariable regression were used to address baseline imbalance and calendar-period confounding. A patient-level segmented time-series model was also used to estimate the pre-implementation temporal slope, the immediate level change at protocol implementation, and the post-implementation slope change.

The final cohort included 186 patients, with 92 in the conventional cohort and 94 in the multimodal-guided cohort. The guided cohort had lower absolute rSO₂ burden, shorter EEG suppression burden, and shorter duration with impaired cerebral autoregulation. Postoperative delirium occurred in 36 of 92 patients in the conventional cohort and 14 of 94 patients in the guided cohort. MoCA-defined 30-day cognitive decline occurred in 31 of 83 patients with available follow-up in the conventional cohort and 10 of 90 patients in the guided cohort. In weighted adjusted models, the guided cohort was associated with lower odds of postoperative delirium (OR, 0.36; 95% CI, 0.17-0.77) and lower odds of 30-day cognitive decline (OR, 0.31; 95% CI, 0.13-0.75). The delirium association was attenuated after adding intraoperative cerebral physiological burden variables. In segmented analyses, neither outcome showed a significant pre-implementation trend; protocol implementation was associated with an immediate reduction in the odds of postoperative delirium (level-change OR, 0.20; 95% CI, 0.05-0.91) and 30-day cognitive decline (OR, 0.17; 95% CI, 0.03-0.92), without evidence of an additional post-implementation slope change.

In adult aortic arch surgery, implementation of a multimodal neuromonitoring-guided cerebral-protection protocol was associated with lower intraoperative cerebral physiological burden, lower postoperative delirium risk, and less MoCA-defined 30-day cognitive decline. These findings support the use of complementary neuromonitoring signals within a structured correction pathway rather than reliance on a single cerebral oxygenation threshold.