Development of a continuous sphygmomanometer using electromagnetic induction

This paper proposes a novel palpable and non-invasive continuous sphygmomanometer, with which continuous arterial pressure can be measured based on electromagnetic induction. The proposed sensor can be attached to the measurer´s fingertip, and single-degree-of-freedom springs, which are interposed between the side of the measurer´s finger and the skin surface side, transmit the arterial pressure to the measurer. At the same time, displacements of the springs are measured by electromagnetic induction, and converted into a measurement of arterial pressure. This mechanism allows measurement of the continuous arterial pressure based on a tonometry approach. In the experiment, the conversion equations from the output voltage to arterial pressure values were verified by comparison with the arterial pressure measured using a commercial continuous sphygmomanometer. The experimental results showed that the determination coefficient of the regression line between arterial pressures measured using the sensors was 0.89 (p <; 0.01). Therefore we can conclude that the proposed sensor enables the non-invasive measurement of continuous arterial pressure.