Under normal conditions, during the passage in the lungs, the red blood cells rich in hemoglobin are loaded or saturated with oxygen, which will then be transported and released to the various tissues of the body.
Oxygen saturation is measured with a transcutaneous electromedical instrument, called an oximeter (oximeter or pulse oximeter), with a shape similar to that of a clothespin.
This device is equipped with a probe and two photo-emitting diodes (sensors that emit light rays of different wavelengths and communicate with a photocell). The blood index is then estimated through the absorption of the light emitted by the oximeter applied to a finger of the hand or an earlobe (anatomical regions rich in capillaries).
The useful element for the evaluation of oxygen saturation is the color of the blood, which, when oxygenated, is of a bright red tint, vice versa, it is darker.
The oximeter or pulse oximeter is an extremely simple and small object. This is not surprising if you think that to use it it is generally sufficient to place the finger inside it and nothing more. The oximeter or pulse oximeter models are very similar to each other. Surely the most common is the finger one, but there are also wrist versions, essentially designed to detect other parameters during sleep and therefore with the need to be well fixed to the arm of the user.
The pulse oximeter allows you to accurately detect the SpO2 level and heart rate. The data is then displayed on an LED screen, both in the form of bars and with numerical expression. They consume very little energy, especially since they are designed to go to stand by or turn off when not in use.
