Abstract: A blood pressure monitor for determining a patient's blood pressure comprises a processor attached to a first input device for receiving an initial input representing the patient's absolute blood pressure, and a noninvasive sensor attached to the patient for measuring at least one physiological function. The processor executes a procedure for evaluating the initial input and the sensed physiological function to determine the patient's blood pressure. A method for determining a patient's blood pressure comprises the steps of storing an initial input representing a patient's absolute blood pressure, noninvasively sensing at least one of the patient's physiological functions, and evaluating the initial input and the sensed input to determine the patient's blood pressure.