peak flow Flashcards
what does PEF measure
highest flow achieved on forced expiration from a position of maximum lung inflation
expressed in L/min
readings are subject to
individual variation depending on age, sex, ethnic origin and height
factors that determine pef
quality of large airways
vol of lungs
elastic properties of lungs
power and coordination of expiratory muscles
what could affect pef reliability in terms of factors that determine pef
any condition that altars the factors that determine pef
a reduction in one factor may be compensated for by an increase in one of the others
meaning pef may not altar
staff could underestimate severity of pts condition
pef may be impaired by
disorders that limit chest movement
resp musculoskeletal problems
obstruction of extra thoracic airways
impairment of nerves that supply resp system
rationale behind evidence based approaches with pef
simple, objective procedure used to measure degree of air flow limitation
doesnt give full representation of lung function
monitors efficacy of treatment and progression of a condition
indications for pef
confirms a diagnosis of asthma
determines severity of an asthma exacerbation
monitors severity of condition in patients with chronic severe asthma
identifies exacerbating factors
monitors progression of resp diseases
evaluates effectiveness of treatments
contraindications of pef
patients who are acutely breathless
patients with severe air flow obstructions
patients unable to take a full inspiration
young children or people with learning difficulties as they may not understand
method of pef
take pef in accordance with personal monitoring regimin even if symptom free
trends more important than isolated results
repeat procedure three times and document best result
when to take pef
`take and document on waking, afternoon and evening
