Autoregulation-Guided Blood Pressure Targets After Stroke Thrombectomy

Abstract

Background and Objectives – The optimal blood pressure (BP) target after endovascular thrombectomy (EVT) remains elusive. The aim of our study was to assess the relationship between individualized autoregulation-based BP thresholds, secondary brain injury, and functional outcomes.Methods – We conducted a prospective observational study of patients with acute ischemic stroke who underwent EVT. Simultaneous recordings of arterial BP and near-infrared spectroscopy were used to continuously monitor each patient's limits of autoregulation for up to 24 hours. Time outside limits of autoregulation was correlated with short-term clinical end points, radiographic biomarkers of secondary brain injury, and functional outcomes.Results – Personalized BP targets were successfully computed in 199 patients. Percent time outside limits of autoregulation was independently associated with early neurologic deterioration (OR 1.2, 95% CI 1.1–1.4, p < 0.001) and worse modified Rankin Scale scores at 90 days (OR 1.22, 95% CI 1.09–1.36, p < 0.001). Patients with hemorrhagic transformation and symptomatic intracranial hemorrhage spent significantly more time above the upper limit of autoregulation compared with those without (18.7% vs 11%, p = 0.02, and 24.9% vs 12.3%, p = 0.024, respectively). Furthermore, time above the upper limit of autoregulation was correlated with net water uptake, a radiographic biomarker of cerebral edema (β = 1.6, 95% CI 0.4–2.8, p = 0.009). In nonrecanalized patients, every 60 minutes below the lower limit of autoregulation was associated with an infarct progression of 16.2 mL (p < 0.001).Discussion – Deviations from personalized BP targets were associated with an increased risk of secondary brain injury and worse functional outcomes. The study proposes autoregulation-oriented BP management as a promising strategy for improving recovery after ischemic stroke.