An apparatus used for reducing the incidence of aspiration in patients using a two-axis inclinometer is disclosed. The apparatus uses a two-axis inclinometer that is attached in the region of the patient's upper body to measure the absolute angular elevation of the patient's upper body, which is then transmitted to a display or other output device. In one embodiment, the instrument can be mounted to the head of a bed in a plurality of orientations and accurately measure the absolute angular elevation of the patient's upper body. In other embodiments the absolute angular elevation of the patient's upper body information is processed and transmitted to the nurses' station or to a data recorder. The disclosure also relates to a method for measuring the physical orientation of a patient, using such two-axis inclinometer apparatus.