Real time analysis of fingerpulse plethysmographic signal and its application on pulse oximetry

Abstract

Pulse oximetry is an innovative technique for continuous noninvasive monitoring of arterial blood oxygen saturation value. It has proved to be very useful for many applications such as clinical management of critically ill infants with cardiac and pulmonary diseases and patient monitoring during surgery. Signal processing algorithm on plethysmographic fingerpulse signal is typically completed in time domain utilizing moving average and peak detection technique. However, it suffers from false detection and errors due to motion artifacts. In this paper, we present an improved method by computing the scaling factor between the red and infrared ac signal. Real-time computer programs are implemented on a personal computer to process the optical sensor output and estimate the desired parameters. Experimental results are provided to illustrate the dramatic improvement.