Pulse Oximeters (Pulse Ox)

Pulse oximetry is a non-invasive method for monitoring a patient's O2 saturation. A sensor is placed on a thin part of the patient's body, usually a fingertip or earlobe, or in the case of an infant, across a foot. Light of two wavelengths is passed through the patient to a photodetector. The changing absorbance at each of the wavelengths is measured, allowing determination of the absorbances.