What do you need to explain?
This is quite a common examination station as it not only tests your understanding of how a 'metered dose inhaler' (MDI) works, but also tests communication skills. The main areas to cover in your explanation, are:
-see what the patient already knows and explain the basics of how the inhaler works
-demonstrate how to use the inhaler
-ask patient to perform procedure (supervised)
-give feedback on their performance and explain commonly encountered mistakes/problems
-ask patient to repeat procedure 'post-feedback'
-answer any questions and check the patients understanding of the key points
The explanation
1. Introduce yourself to the patient, confirm their identity, and explain you are going to teach them how to use an inhaler.
2. Explain what the purpose of the bronchodilator medication within the inhaler is. You can use a statement like ?this medication relaxes the air passages in your lungs, making it easier for you to breathe?. Highlight the fact that for maximal effects, the inhaled medication needs to reach as 'deep into' the patient's lungs as possible. Also mention that even with a 'good' technique, only around 15% of the contents actually reach their target. For this reason, a poor technique is likely to not provide adequate administration of the drug.
3. Work through the individual steps of the procedure:
remove the plastic mouthpiece cover
shake the inhaler
hold the inhaler vertically (ideally in their dominant hand) with the index finger over the top of the canister, and the mouthpiece close to their mouth
breathe all the way out
put the mouthpiece into the mouth with close lips tightly round it, forming a tight seal
press firmly down on the canister (releasing the medication) just as you begin to breathe in
take in a deep breath slowly so that the medication goes 'deep' into your lungs
hold your breath for around 10 seconds (count in your head)
relax and breathe normally
rinse out your mouth with water (particularly for steroid inhalers)
4. Then ask the patient to go through the process in their head, step-by-step. Once they are happy with the sequence of events, ask the patient to perform the procedure, with you observing their technique.
5. Correct any errors in the patient's technique, and get them to repeat it again once these have been discussed.
6. Explain common problems that other patients encounter:
difficulty in holding the inhaler in one hand
not breathing all the way out beforehand
not triggering the spray at right time (has to be timed as inspiration begins)
not breathing in/holding their breath for long enough
explain that spacer devices are available for young patients/if they continue to experience difficulty in using the inhaler - alternatively, self-triggering metered dose inhalers are available to automatically do the 'pressing the canister and releasing drug' part of the process
7. Ask patient if they have any questions or concerns, and resolve these. Thank the patient and conclude the consultation.
Commonly used drugs
-Salbutamol: beta-2 adrenoreceptor agonist (short-acting bronchodilator - useful in acute attacks, side-effect = tachycardia)
-Salmeterol: beta-2 adrenoreceptor agonist (long-acting bronchodilator)
-Ipratropium bromide: muscarinic antagonist (anticholinergic) ? bronchodilator (used more in COPD)
-Sodium cromoglycate: stabilises mast cells and reduces de-granulation
-Beclomethasone/fluticasone: inhaled corticosteroid (can be low or high dose - not useful acutely)
-Prednisolone/methotrexate: oral corticosteroids
