A pulse oximeter is a medical device which fundamentally measures the arterial oxygen saturation of haemoglobin (Hb) of a patient, with a probe attached to his/her body where the blood flow is excellent for more concise results. The ideal spots are finger, toe or ear lobe which is then linked to a computerized unit. This method of measuring oxygen in blood is known as Pulse Oximetry.
How Does A Pulse Oximeter Work?
A pulse oximeter uses red and infrared light to detect oxygen in the patient’s blood stream. Infrared light would be absorbed more by hemoglobin which carries the oxygen, but red light will be allowed to pass through. On the other hand, red light would be absorbed more by hemoglobin without much oxygen but infrared light will be allowed to pass through. Once the information are gathered and transmitted to the machine or device, the ratios of red to infrared light are calculated and compared to a model table to determine the results. A good reading usually ranges between 90 to 100 saturation.
Conventional And Newer Generation Of Pulse Oximeters
Conventional pulse oximeters have some disadvantages. Whenever there are movements or poor blood circulation, the accuracy of the readings will be affected. As a result, it makes it very difficult to make medical decisions. To overcome this, an additional arterial blood gas test is usually required to validate pulse oximeter readings. “Newer Generation” of pulse oximeters on the market have significantly improved the ability to read through motion and low perfusion issues.
My next article will explain more in details on how to choose a pulse oximeter.