Cerebro‑Cardiovascular Coupling During Extracorporeal Membrane Oxygenation Using Cerebral Oxygenation, Doppler Flow, and Echocardiography

Cerebral injury remains a major contributor to morbidity and mortality in VA‑ECMO patients. Disruption of cerebral autoregulation during extracorporeal support may predispose to neurological damage. This prospective study evaluated cerebral hemodynamics in 17 adults with cardiogenic shock supported by femoro‑femoral VA‑ECMO using transcranial Doppler (TCD) and regional cerebral oxygen saturation (rSO ₂ ), correlating these measurements with echocardiographic and clinical outcomes. Bilateral middle cerebral artery (MCA) velocities, peak systolic (PSV), mean flow (MFV), end‑diastolic (EDV), and pulsatility index (PI) were recorded and compared with ejection fraction (EF), left ventricular outflow tract velocity time integral (LVOT VTI), and cardiac index (CI). Pulsatile flow was detected in 85.9% of MCA readings, with mild left‑sided dominance and minimal rSO ₂ variation. A U‑shaped correlation emerged between rSO ₂ and PI, indicating optimal oxygenation at mid‑range PI values (0.6–1.2). Lower and higher PI values were associated with increased mortality. Transcranial Doppler‑derived indices, particularly PSV and MFV, correlated strongly with EF ( p = 0.022) and LVOT VTI ( p = 0.044), outperforming rSO ₂ in prognostic value. Ejection fraction < 10%, LVOT VTI < 3.08 cm, and CI < 0.52 L/min/m ² predicted nonpulsatile flow with high accuracy. Combined TCD and rSO ₂ monitoring offers bedside insight into cerebral perfusion and cardiac performance during VA‑ECMO. These exploratory findings are hypothesis‑generating and require confirmation in larger, prospective cohorts.