COPD Diagnostic Tests: Pulmonary Function, Spirometry, and More
Pulse Oximetry continued...
Oximetry can be used to help evaluate low oxygen levels in the blood. It can also help in deciding if there is a need for oxygen therapy. However, in patients with severe COPD, an arterial blood gas test is often preferred for making these decisions. An arterial blood gas test is more accurate and gives more information on the PaCO2 and pH values in the body. Pulse oximetry is very useful for measuring oxygen levels while walking, exercising or during sleep. These measurements can provide important information for deciding the earliest need for oxygen therapy. Pulse oximetry can also help determine how well the oxygen therapy is working. However, pulse oximetry can undervalue oxygen levels. This is especially true if the pulse is rapid and harder to gauge.
If you have your own oximeter, talk with your health care provider to decide how to use it correctly. It is not always a good idea to constantly monitor your oxygen levels with every activity you do. Overuse of an oximeter can lead to unnecessary fear and anxiety.

