Abstract DP033: Temporal Dynamics of Cerebral Autoregulation After Thrombectomy and Association With Functional Outcomes

Introduction: Impaired cerebral autoregulation in large vessel occlusion (LVO) stroke has been associated with poor functional outcomes. However, the evolution of autoregulatory function in the immediate post-mechanical thrombectomy (MT) period has not been well defined. Methods: We conducted a prospective observational study of patients with anterior circulation LVO undergoing MT. To track patients’ cerebral autoregulatory function, cerebral oximetry index (COx)—a rolling correlation between mean arterial pressure and near-infrared spectroscopy–derived regional oxygen saturation—was continuously recorded for 24 hours post-procedure. Associations between mean COx and dichotomized 3-month functional outcomes (modified Rankin Scale mRS 0-2 vs > 2) were assessed using multivariable logistic regression and adjusted for relevant confounders. Temporal trajectories of COx were compared between hemispheres and stratified by outcome. Results: Among 196 patients (mean age 70.5 ± 16.1 years; admission NIHSS 13.7 ± 6.4), higher mean COx was independently associated with unfavorable outcomes (adjusted OR 1.29 per 0.1 increase; 95% CI 1.03–1.63; p < 0.05). Post-reperfusion, COx values were elevated in both outcome groups. Approximately 4 hours post-MT, patients with favorable outcomes exhibited a significant decline in COx in both hemispheres, whereas those with unfavorable outcomes maintained elevated COx levels. Over 24 hours, COx remained lower in patients with better recovery (Figure 1). Conclusions: Impaired autoregulation, indicated by higher mean COx, is associated with poor functional recovery following MT. Every 0.1 increase in mean COx during the first 24 hours correlates with a 29% higher likelihood of unfavorable outcome. Dysfunction emerges early post-reperfusion and involves both hemispheres, though less severely contralaterally. Tracking autoregulatory recovery may support individualized blood pressure targets and guide interventions to optimize stroke outcomes.