PEF Flashcards
PEF stand for?
Peak Expiratory Flow
Define PEF
Its the maximal Flow taken During FVC maneuvers
If PEF reported from FVC maneuvers, it’s expressed in?
L/sec
If PEF reported from Peak flow meter, it’s expressed in?
L/min
3 ways to obtain PEF?
1) FVC maneuver
2) a device that directly measures flow
3) volume displacement spirometer and driving flow from volume change
PEF Technique
1) set the device or zeroed as required
2) positions
*Standing position for peak flow meter
*setting upright position for FVC maneuvers
3) maximal inhalation ( rapid but not forced)
4) rapid maximal exhalation asa soon as teeth and lips around mouthpiece ( 1 to 2 sec )
5) neck in natural position
6) no more than 1sec for hesitation
Why the neck should be in natural position during PEF?
To avoid tracheal compression because it will reduce PEF
PEF depends on?
Effort dependent
How to report PEF?
at least three performed and recorded with the order in which the values were obtained
Why all readings of PEF should be recorded?
To detect induced bronchospasm
List the criteria of acceptability of PEF
1) position ( standing or setting upright
2) maximum inhalation bu not force, maximum exhalation without holding breath
3) at least 3 trials performed amd recorded in order
4) Two of the 3 should be repeatable ( within 0.67l/sec or 40l/min )
5) largest PEF reported
What is more important in Peak flow meter ( precision or accuracy) and why?
Precision
To detect changes from serial measurements
What ranges should PEF have?
For children
60 - 400 l/min
For Adults
100 - 850 l/min
PEF measurements are particularly useful For who? and when?
Monitoring asthmatic patients at home
Why daily monitoring of asthmatic patients is useful?
For early detection of asthmatic episodes