Asthma pre-work (+COPD) Flashcards
Draw the lung volume graph and label
What is spirometry?
- Forced expiration
- Breathing out as quickly as possible from maximum inspiratory level
Define spirometry values
- FVC - volume breathed out during forced expiration
- FEV1 - volume breathed out during first second
- FEV1/FVC - proportion of FVC that is breathed out in the first second
- PEFR - peak expiratory flow rate - gradient of the graph at time 0, corresponds to the highest rate of flow of air from lungs
Four patterns of spirometry
- Normal - normal FEV1, FVC and FEV1/FVC ratio
- Restrictive - reduced FVC but with normal FEV1/FVC ratio
- Obstructive - normal FVC but reduced FEV1 so reduced FEV1/FVC ratio, PEFR also reduced
- Mixed - FVC reduced AND FEV1/FVC is reduced
Bronchodilator reversibility and spirometry
- Involves repeating spiro testing 20-30 mins after administering dose of bronchodilator (eg salbutamol 2x 200mcg puffs ideally via large volume spacer)
- If reversible - improvement in FEV1/FVC ratio
What is PEFR?
- PEFR measures the maximum flow of air during expiration
- Happens at the beginning of expiration
- Is the gradient of the spirometry volume-time graph at time 0
How often do we ask patients to do peak flow with asthma?
- Twice daily for 2-4 weeks initially while diagnosing
- Then asked to check regularly to monitor asthma
How to do peak flow
- Set the arrow to 0
- Hold with fingers at edge of device, not obstructing the arrow
- Take the deepest breath in you can
- Seal mouth around mouthpiece
- Blow out as hard as fast as you can
- Note the reading where the arrow is pointing
- Record in peak flow diary - available at asthma.org website
What is FENO?
- Newer test used in primary care
- Fraction exhaled nitric oxide test
- Measures nitric oxide exhaled in breath
- These levels are elevated when inflammation within lungs (eg in asthma)
What can affect FENO?
- Smoking
- Inhaled corticosteroids
- Not always raised in people with asthma - NICE says 1 in 5 people with positive result will not have asthma, 1 in 5 with a negative result will have asthma
Specialist tests for asthma
Direct bronchial challenge - used if there is doubt of diagnosis
How to do spirometry?
- Sit comfortably
- Wear a clip on your nose to make sure all the air from your lungs goes into the mouthpiece.
- First do a relaxed breath - it is often described as a big sigh into the machine.
- Then take a deep breath in and breathe out as fast and as hard as you can, for as long as you can, through the mouthpiece.
- You will need to blow a few times, and put as much effort into the test as you can, to get an accurate result.
Advice for before FeNO test
Leave enough time to get to your appointment, so you’re not rushed and tired before the test.
* You should avoid too much physical activity or exercise for at least an hour before the test.
* If you smoke, avoid smoking at least an hour before the test.
* Hot drinks, caffeine and alcohol can all affect the result, so avoid these at least an hour before the test.
* Foods such as green leafy vegetables and beetroot can also affect the result, because they are rich in nitrates. Avoid eating these for at least three hours before the test.
* You can take your regular medicines as usual before the test. But let the person doing the test know about any medicines you’ve taken.
How to do FeNO test?
- breathing into a mouthpiece attached to a hand-held monitor. The reading shows up on the monitor screen .
- First, you need to breathe in deeply, with your mouth open.
- Then you’ll be asked to breathe out slowly and steadily into the mouthpiece until your lungs are empty.
- May need to do a few times
3 different types of inhaler
- MDI’s - pressurised metered dose inhalers, generates aerosol which is inhaled
- DPI’s - dry powder inhaler, dry powder is inhaled
- SMI’s - soft mist inhalers, soft mist is inhaled
5 drug groups of inhaler
- ICS
- SABA - agonist
- LABA - agonist
- SAMA - antagonist
- LAMA - antagonist
Combination inhalers
- ICS + LABA (used in asthma and COPD)
- LABA + LAMA (mainly COPD)
- ICS + LABA + LAMA (COPD)
When should spacers be considered?
- In anyone struggling with inhaler
How to use pMDI?
- When first get or not used for 5 days or more, need to test it
- Take cap off, shake well, point away from you and press cannister to release puff into air - how many test sprays depends on inhaler, check instructions
- If dose counter, check not empty
- Take cap off, check nothing inside mouthpiece
- Shake well
- Sit or stand up straight
- Tilt chin up slightly
- Breathe out gently and slowly away from inhaler until lungs empty and ready to breathe in
- Lips around mouthpiece to make tight seal
- Breathe in slowly and steadily
- Press cannister on inhaler once at same time
- Breathe in slowly until lung feel full
- Hold breath off mouthpiece for up to 10seconds or as long as can
- Breathe gently away from inhaler
- If need 2 puffs, wait 30s, shake inhaler and repeat
- Replace cap
- If steroids, rinse mouth out and spit it out
Using spacer with pMDI - two techniques
- Single breath and hold
- Tidal breathing/multiple breath
Using spacer with pMDI technique
- Remove cap and shake inhaler well, check mouthpiece is clean and nothing in it
- If spacer has valve, check this is facing upwards
- Put inhaler into hole at back of spacer
- Take cap off spacer if it has one
- Sit or stand straight and slightly tilt chin up
- Breathe out gently and slowly away from spacer until empty lungs
- Put lips around spacer mouthpiece and create tight seal
- Press cannister on inhaler once
- Breathe in slowly and steadily untul lungs feel full
- Hold breathe up to 10s or as long as comfortable
- Breathe out slowly
- Spacers can make noise if breathing in too fast
- If second puff needed, wait 30s to 1 minute, shake inhaler and repeat
- Replace caps
- If steroid containing, rinse mouth with water and spit out
Good videos for inhaler technique
Asthma and Lung UK
Spacer and tidal breathing/multiple breathe technique technique with pMDI
- Used in asthma attack or if cannot hold breath for 5 seconds after inhaler
- Can have spacer with mouthpiece/mask if cannot get tight seal
- Hold inhaler upright and take cap off, check mouthpiece is empty
- Shake well
- If spacer has valve, check is upwards
- Put inhaler into hole at back of spacer
- If mouthpiece is capped, remove this
- Sit or stand up straight
- Slightly tilt chin up
- Lips around mouthpiece and tight seal
- Press cannister on inhaler once
- Breathe in and out slowly and steadily into spacer 5 times
- Remove inhaler and spacer from mouth
- If need second puff, wait 1 minute, shake inhaler and rpt
- Some make whistling sound if breathing in too fast
- Can use with large volume spacer too
- Valve should make clicking noise with tidal breathing as it opens and closes
- Remove inhaler from spacer and replace caps
- If steroid containing, rinse with water and spit out
How to use turboinhaler
- Dry powder device
- When first get, need to get ready to use
- Twist off cover and hold upright with coloured base at bottom
- Turn coloured base as far as it will go in one direction and then all the way back again
- Doesn’t matter which way you turn it first
- Should hear click on one of these turns
- Do this once more
- You won’t need to do this again - it is now ready to use
- To use, twist off top cover
- Check mouthpiece is clean
- Check dose counter isn’t empty - when 20 doses, red strip will appear in window, when to bottom of window is empty
- Twist coloured base as far to right as will go and then to left until you hear a click
- Dose is now ready
- Sit or stand up straight and slighty tilt chin up
- Breathe out gently and slowly away from inhaler iuntul lungs empty
- Hold inhaler horizontally - not upside down as powder can fall out
- Create tight seal around mouthpiece
- Inahler quickly and deeply
- Hold breath up to 10s or as long as can
- Breathe out gently away from inhaler.
- Repeat if need 2nd puff
- Replace cover