oximetry

(physiology) Optical measurement of the degree of oxygen saturation of the blood hemoglobin by determining the variation in the color of the blood.

A technique that employs an oximeter, a photoelectric photometer, to measure the oxygenated fraction of the hemoglobin. This fraction is usually expressed in percent, which is referred to as the “oxygen saturation of blood.”

One type of oximeter is designed to measure the oxygen saturation of blood circulating in a particular tissue of an intact animal or human. The tissue most commonly studied is the cartilaginous pinna of the ear, and the instrument used for this purpose is called an ear oximeter.

Another type of oximeter is designed to measure the oxygen saturation of blood during, or shortly after, its withdrawal from various sites in the vascular system. Such a device usually is designated a cuvette oximeter.

The measurement of the oxygen saturation of hemoglobin in a sample of blood with the use of an oximeter.

Measurement of the oxygen content of arterial blood.

• pulse o. — use of a spectrophotoelectric instrument applied to the skin which measures pulse rate and the percentage of oxygenated and reduced hemoglobin.