Measuring Oxygen Saturation

Normal arterial blood oxygen saturation levels in humans are 95 100 percent.

Measuring oxygen saturation.

In critically ill clients a more invasive and continuous monitoring system is used to measure arterial blood gases through an arterial line. However oxygen saturation may be lower if you have a respiratory disease or congenital heart disease. An estimate of your oxygen level can be easily measured with a pulse oximeter a non invasive device that attaches to the end of your finger a more accurate method of measuring oxygen levels is with an arterial blood gas abg study a blood test that is performed by taking a blood sample from an artery usually. If the level is below 90 percent it is considered low and called hypoxemia.

Oxygen saturation should always be above 95 percent. Oxygen saturation is a term used to define how much oxygen your blood is carrying. See figure 4 1 for a pulse oximeter. A pulse oximeter is a medical device that indirectly monitors the oxygen saturation of a patient s blood as opposed to measuring oxygen saturation directly through a blood sample and changes in blood volume in the skin producing a photoplethysmogram that may be further processed into other measurements.

The pulse oximeter may be incorporated into a multiparameter patient monitor. You can measure the blood s percentage of oxygen saturation using a pulse oximeter a clip like sensor device that is placed on a thin part of your body such as an earlobe or nose. A measurement of your blood oxygen is called your oxygen saturation level.