The three most important are: 1  SaO2. Itâs a percentage that shows how saturated your arterial blood is with oxygen. 2  PaO2. Itâs the partial pressure of arterial oxygen. . 3  Itâs the same as SaO2, although itâs estimated by pulse oximetry. A normal value is 95-98%, although 90% or better is usually considered acceptable.
A peak flow meter is a portable, inexpensive, hand-held device used to measure how air flows from your lungs in one âfast blast.â In other words, the meter measures your ability to push air out of your lungs.
Your peak flow meter can help warn you of an asthma attack, even before you notice symptoms. If your score shows that your breathing is getting worse, you should take your quick-relief medicines the way your asthma action plan directs. Then you can use the peak flow meter to check how well the medicine worked.