Understanding Pulse Oximetry

Introduction

The concept of monitoring hemoglobin oxygen saturation by optical means has been known for over 40 years. It is, however, only very recently that real time oximeter monitors have become commercially available – mainly due to discovery of the pulse oximeter technique and the revolutionary development in electronic computer technology.

The Pulse oximeter extracts the pulsatile arterial blood signal from an in vivo measurement, and therefore needs only 2 wavelengths to measure oxygen saturation – in contrast to earlier ear oximeters that used up to 8 wavelengths to filter out signals from tissue and venous blood.

This has significantly simplified the instrument, the probes, and the oxygen saturation calculations, and made development of a small, inexpensive clinical monitor possible.

The Pulse oximeter’s simple, convenient technique for continuous monitoring of arterial oxygen saturation fulfills the clinician’s goal of patient monitoring – to provide early warning of undetected hypoxemia during anesthesia, post-operative recovery, and intensive care. The simplicity of this monitor has also made it possible to review home care of chronically in patients.

Oxygen saturation measurement can now be done continuously and noninvasively using the Radiometer Pulse oximeter.