Last week’s article on the relationship between oxygen and shortness of breath may have left some questions unanswered, such as what are the oxygen levels that require oxygen therapy and what are the best ways to check them and if oxygen therapy does not usually relieve shortness of breath why use it. So, let me backtrack and try to answer some of these questions. Those of you who listened to my radio show on WRTA last Tuesday already know the answers to some of these questions but here goes.
A safe oxygen level is determined in part by what technique is used to test you. If you are using a pulse oximeter on your finger the absolute cut off would be 85%, however, the pulse oximeter has a range of plus or minus 3 so we will tell the patient that their safe level is 88% or above. If you are using a blood gas technique, which is a blood sample taken usually from an artery in the wrist, then the oxygen level should be above 55 mmHg. These findings do not take into account your levels with activity or at night when you are sleeping. They also do not take into accounts other diseases you may have such as heart disease and since you need an adequate amount of hemoglobin to carry the oxygen to your tissues you need to have a reasonably normal blood count.
Oxygen use is more complicated than most people think.
