A Pulse oximeter is a unit that monitors oxygenation of blood by measuring the percentage of haemoglobin saturated with O2. It is attached to the finger or ear lobe and measures the blood flow past a computerized probe in the meter. A sound or graph is usually displayed to show each pulse beat.

650nm & 805nm are the wavelengths of light usually utilized in an oximeter’s probe to record absorption and saturation of the haemoglobin in a patient’s blood. Oxygenation in the blood is measured by this saturation level measured. Slow blood flow may introduce problems in normal pulse oximeter functions due to the units mechanism of measuring blood flow.

Several situations may cause a pulse oximeter to become inaccurate. Vasoconstriction and Venous congestion have been known to negatively affect readings. Some more less scientific causes of bad readings are due to bright overhead lights and nail varnish. Another cause of mis-readings can come in the form of there being carbo-xyhamoglobin (methaemglobin) in the blood being metered; because a pulse oximeter is unable to distinguish between types of haemoglobin.

When under anaesthesia, pulse oximeters are used to monitor oxygenation and pulse rates. During mechanical ventilation and other intensive care situations, pulse oximeters have been used to great success in the detection of oxygenation related problems before they are physically realized. Additionally, oximetry is used to analyze whether oxygen therapy is necessary in a patient. Alerting users of a state of hypoxia is also another helpful usage.

Again, monitoring oxygenation is the main purpose of a pulse oximeter. These devices, however, are not able to detect metabolism of oxygen. Oxygen metabolism measuring needs critical data regarding carbon dioxide levels.

Pilots flying in a non-pressurized airplanes use portable pulse oximeters to measure the amount of supplemental oxygen that is required, if required. In situations where oxygen levels may decrease, such as high altitudes and vigorous exercise, portable pulse oximeters have been very useful. People like mountain climbers and professional athletes have utilized these portable oximeters for this purpose.

New uses have been found for pulse oximeters. One such use is the detection of blood loss. There has been the discovery of an algorithm that correlates blood volume and oxygen absorption changes in the blood.

Household pulse oximeter units can now be found at a variety of places and at prices that normal families can afford. Brand names like Nellcor, Checkmate, and Nonin have finger pulse oximeters for sale like portable oximeter and finger pulse oximeter.