Cerebral Perfusion Variation During Blood Pressure Changes in ICU

"Measurement of cerebral blood velocity in the middle cerebral artery by transcranial pulsed Doppler (TCD) (Mean velocity, Vm, cm/s) (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. For neuro-injured patients with intracranial pressure monitoring (ICP), the lower limit of cerebral perfusion pressure (CPP = MAP - ICP) will be set at 50 mmHg"