A system for determining onset of an acute hypotensive episode, the system includes a plurality of collectors configured to determine heart rate, mean arterial pressure, stroke volume, total peripheral resistance, and/or age of a patient, an estimate model configured to receive data from the collectors, a simulate model configured to receive information from the estimate model to simulate operation of an effector portion and a neural portion of an arterial baroreceptor reflex pathway, and a prediction model configured predict onset of an acute hypotensive episode based on results from the simulate model. A method and a computer software code for determining onset of an acute hypotensive episode are also disclosed.