A blood pressure monitoring system is disclosed for monitoring blood pressure during stress testing or other physical activity as well as when quiescent. The blood pressure monitoring system of the present invention includes an inflatable cuff utilized in conjunction with a controllable electric air pump and deflation valve. Audio transducers are utilized to detect pulse sound at the proximal and distal edges of the inflatable cuff and pulse sound amplitudes as well as the time delay between pulse sounds proximal to the cuff and distal to the cuff are determined. Pulse sound amplitudes are then multiplied by time delay values for selected cuff pressures to generate a greatly enhanced blood pressure evaluation curve. In a preferred mode of the present invention digital filters and statistical analysis are then employed to determine systolic and diastolic blood pressure from the evaluation curve. Further novel features of the blood pressure monitoring system of the present invention include the ability of the system to select a trigger signal from multiple electrocardiographic leads by selecting the particular electrocardiographic lead with the least amount of noise present and the capability of modifying the inflation pressure and deflation rate of the cuff to permit either maximum accuracy or minimum measurement time during operation.
Harry H. Peel;John S. Brisco;Mark E. Moczygemba;Robert L. Neatherlin;Brenda A. Sargent