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.
Due to the wide range of ânormal' values and high degree of variability, peak flow is not the recommended test to identify asthma. However, it can be useful in some circumstances. A small portion of people with asthma may benefit from regular peak flow monitoring.rom Wikipedia, the free encyclopedia. The peak expiratory flow (PEF), also called peak expiratory flow rate (PEFR) is a person's maximum speed of expiration, as measured with a peak flow meter, a small, hand-held device used to monitor a person's ability to breathe out air.