ventilation and pulmonary function Flashcards
1
Q
pulmonary function testing
A
- used to identify general breathing difficulties at rest and during exercise
- commonly assessed with a spirometer
- measures volumes (static) and flow (dynamic) while inhaling and exhaling
2
Q
increased ventilation
A
- with exercise you breath faster and deeper
- during maximal exercise, healthy individuals retain a ventilatory reserve
- reserve is normally %30 in normal individuals
- fittest women have less of a reserve because of smaller lungs and surrounding accessories
- uses many accessory muscles to breathe like the diaphragm, intercostals, sternocleidomastoid, etc.
3
Q
dynamic ventilation chart
A
- flows and volumes
- chart is smaller at rest and bigger during exercise
- need faster air flow to more volume of air
4
Q
spirometry
A
- in “normal” individuals, greater than 70% of FVC can be inhaled in 1s
- remaining 30% depends on how you move air through the airways
- uses the resting forced vital capacity test (FVC and FEV1)
- is a measure of expiratory ability and general resistance to expiration, expressed as a percent
5
Q
dynamic forced ventilation
A
- effort independent = small airways and troubles with resistance
- PL, Ppl, alveolar pressure, and transairway pressure
6
Q
PL
A
- pressure generated by lung recoil
7
Q
Ppl
A
- pleural pressure generated by active inspiration or expiration
8
Q
alveolar pressure
A
- the sum of PL and Ppl and expressed relative to atmospheric pressure
9
Q
transairway pressure
A
- the difference between Ppl and local alveolar pressure
10
Q
effort dependent and independent flow
A
- dependent : pressure differential pushes air out , lungs and ribs = more pressure b/c they recoil together
- independent: as lungs recoil, pressure decreases and returns to normal, balances pressure and compression
- see pics for more details*
11
Q
basic spirometry
A
- uses the resting forced vital capacity test
- maximal exhalation (preceded by a max inhalation ) around 6 sec
- should be done in a sitting position (obese people will have better values standing )
- nose-clips should be used
- participant should exhale as forcefully as possible and for as long as possible
- ratio of FEV1/FVC should be greater than or equal to 85%
- if it is less than %70 it represents some pulmonary obstruction (like asthma)
- a bunch of prediction equations to compare against norms
12
Q
end of test criteria for basic spirometry
A
- when participant can no longer exhale or plateau in exhaled flow (less than 0.025L/s)
- test should be repeated at least 3x (2-3 min of recovery between)
- two best performances should be within 150ml
- if not continue with additional tests to look for maximal values
- take highest values
13
Q
exercise spirometry
A
- used to investigate breathing difficulties during exercise
- influences O2 uptake
- perform a resting FVC test, want people to breathe hard
- perform a single stage exercise test of 6-8 min duration at 80-90% of HR max or predicted
- perform post-exercise FVC tests at 5, 10, and 15, and 20 min
- see how FVC test changes and if it changes
- onset of these conditions can happen late not not immediately after exercise
14
Q
Eucapnic voluntary hyperventilation test
A
- also used to assess breathing difficulties
- mimics an exercise challenge
- perform resting FVC test
- perform of 6 min of hyperventilation (air + 5% CO2)
- tidal volume fixed at 85% of TCL or FEV1
- breathing rate fixed at 30 bpm
- perform post-exercise FVC tests at 5, 10, and 15, and 20 min
- dries and cools airways = bronchoconstriction
15
Q
Exercised induced bronchoconstriction
A
- a drop in FEV1 10% from pre-exercise values
- narrowing of bronchi due to smooth muscle contraction that can be induced by exercise, heavy breathing, cold dry air, and or “bad air”
