A method of evaluating patients suspected of suffering from an acute stroke, the method comprising: a) obtaining signals of impedance plethysmography (IPG), photoplethysmography (PPG) or both, in the patient b) processing the one or more signals to obtain one or more measures of cerebral hemodynamics comprising an estimate of cerebral blood flow, of the patient and c) notifying medical personnel if the estimate of cerebral blood flow increases by a predetermined relative or absolute amount.
