A novel method for the measurement of oxygen saturation in arterial blood

Abstract

A novel and noninvasive method of estimation of oxygen saturation in arterial blood (SpO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> ), employing the popular photoelectric plethysmographic (PPG) principle, is presented here. Based on a refined model for the attenuation of light in a PPG sensor, a simple method of computation of SpO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> that is not influenced by interfering parameters of a patient such as skin colour and quantum of intervening tissue between the source and the detector in a PPG sensor as well as sensor dependent parameters such as source intensity and detector sensitivity is identified. Preliminary results obtained on a prototype pulse oximeter, built and tested, demonstrate the practicality of the proposed method.