Cerebral Perfusion Variation During Blood Pressure Changes Under General Anesthesia

"Continuous measurement of blood velocity in the middle cerebral artery by transcranial pulsed Doppler (TCD) Atys Medical TCD-X®. The probe attachment system on the patient's head looks like a pair of glasses; it is light and comfortable. The orientation of the robotic probe is automatically readjusted to ensure stable recording quality over time. (recorded on Data Warehouse Connect).~For all patients Vm in (cm/s) will be collected during the adjustment of the mean arterial pressure level between 90% and 70% of the baseline value, without ever going below 60 mmHg for the patients at low risk and 80 mmHg for the patients at high cardiovascular risk."