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.

Measuring oxygen saturation.

The pulse oximeter may be incorporated into a multiparameter patient monitor. A measurement of your blood oxygen is called your oxygen saturation level. 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. If the level is below 90 percent it is considered low and called hypoxemia. 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. 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.

However oxygen saturation may be lower if you have a respiratory disease or congenital heart disease. Oxygen saturation is the fraction of oxygen saturated hemoglobin relative to total hemoglobin unsaturated saturated in the blood the human body requires and regulates a very precise and specific balance of oxygen in the blood. Normal arterial blood oxygen saturation levels in humans are 95 100 percent.