Inhaler technique – the why and the how

Inhaler technique

Inhaled medications – Inhaled medications are essential for treating and asthma and COPD amongst other respiratory conditions. The big advantage of using inhaled medication is that the drug targets the lungs directly to where it is needed with little systemic absorption thereby lowering the risk of side effects when compared with oral or intravenous administration. On the other hand, inhaled medication is not suitable for everyone particularly those with poor inspiratory effort, poor dexterity, learning difficulties or cognitive impairment.

A systematic review of inhaler technique involving 54,354 adults and children with either asthma or COPD investigated the extent and prevalence of inhaler use (Sanchis et al, 2016). The review assessed the most common errors made by patients, the percentage demonstrating correct, acceptable or poor technique and thirdly the change in outcomes over time. The overall results demonstrated a prevalence of correct inhaler technique in 31% of adults and children, acceptable technique in 41% and poor technique in 31%. The most frequent errors reported were incorrect preparation of the device, errors in co-ordination, incorrect speed or depth of inspiration and not holding the breath after inhalation (Sanchis et al, 2016). In the same study, there were difficulties reported in firing the MDI and breathing from the chamber.

Each inhaled device has specific characteristics for its use and care and therefore can be confusing for patients on more than one different device. Every effort should be made to ensure that patients are prescribed the same device for all their inhaled medications. However, this may not be possible depending on the drugs required to be delivered. In recent times, this has proved easier as there has been a surge of inhaler devices to the market which can be used as combination therapies.

Good inhaler technique is essential

• to optimize drug deposition into the lungs
• to manage treatment failure
• to improve symptoms which may result in de-escalation of treatment
• to prevent inappropriate escalation of treatment
• to avoid local side effects eg dysphonia, oral candidiasis

Poor inhaler technique is associated with poor asthma control, frequent emergency department and GP visits, increased admission to hospital, increase in the levels of morbidity and mortality, increase costs, and inappropriate escalation of treatment (Hamdan et al, 2013). In COPD, poor inhaler technique can lead to poorly controlled COPD. In a study by Rogliani et al (2017), it was demonstrated each device has its pros and cons with age, cognitive status, visual acuity, manual dexterity, manual strength and ability to co-ordinate the inhaler all having an influence on whether the patient can use the inhaler (Rogliani et al, 2017)

Types of inhaled medication

Basically, there are 5 ways to deliver inhaled medication – meter dose inhalers (MDIs), breath activated devices, soft mist inhalers (SMIs), ) dry powder devices (DPIs) and nebuliser. For the purpose of this article, aerosol devices, breath actuated devices, DPIs and the soft mist inhaler will be addressed. The technique for each group will be discussed later in the article.

Inhaler dose vs delivered dose

Drug deposition within the lungs is dependent on the size of the drug particles. Particle size of more than 5 microns are deposited in the mouth and oropharynx. Particles measuring 2-5 microns are deposited in the upper and central airways and particles less than 2 microns are deposited in the peripheral airways and alveoli (Education for Health, 2015)

The drug dose stated on the label is not the dose that is delivered to the lungs. The nominal dose is the dose that is stated on the label. The emitted dose is the amount released from the mouthpiece and the fine particle dose is the amount of drug released that is 5 microns or less in diameter that is deposited in the lungs.

Considerations when choosing a device…

Several considerations need to be considered when deciding on the appropriate device for a patient. Experience and research have shown that involving the patient in choosing the device aids better adherence (Lenney et al, 2000). What the patient wants from their inhaler, the drug formulary, the range of devices, the range of therapies and the cost of the medication are all considerations which health professionals should consider. From the patient’s perspective, the medication needs to fit into their lifestyle, their ability to use the device and the presence of physical or sensory impairment all can impact on the patient’s ability or willingness to use the device.

The environmental impact of inhaled medication has become a concern for both patients and health care professionals. GINA (2023) addresses the issue in their most recent guidelines.

Propellants in the current pMDIs have 25x global warming potential than DPIs. New propellants are currently in development and are awaiting approval (GINA, 2023).

Inspiratory effort

For the drug to be optimally delivered to the lungs, adequate inspiratory effort is required. This can be checked by using an in-check dial device (Figure 1) to ensure the patient has sufficient inspiratory effort for the drug to reach the airways. A minimum inspiratory effort of 30 litres/min is required for optimal deposition. Some devices require higher inspiratory effort. Poor inspiratory effort will result in poor control of symptoms and an increased risk of side effects as the drug is deposited in the mouth and oropharynx.

Starting inhaled medication –a check list…

• Inhaler should not be prescribed unless the patient has been shown how to use it
• If the medication is to be repeated, inhaler technique should be reassessed
• Demonstrate inhaler technique using placebo devices which are available from all pharmaceutical companies
• Do not switch inhaler unless the patient’s technique has been reviewed and assessed
• Advise patient re storage and maintenance of inhaler device
• Does the inhaler suit the patient, their lifestyle and the environment

Common errors in inhaler technique

The errors with inhaler technique can be categorised as follows: errors with the device, errors with patient, and errors with the health professional (Price et al 2012). Cultural barriers also exist with inhaler use. In some population, the use of an inhaler is seen as improper or impolite and oral medications may be preferred (Griffiths et al, 2004).

Errors with the device include:

• Incorrect preparation of the device
• Poor inspiratory effort
• Using different devices to deliver different drugs – where possible the devices should be the same
• Poor dexterity – inhaler aid devices are available to assist patients with reduced dexterity
• Poor co-ordination of actuation and inspiration

Errors with the patient include:

• Reduced dexterity which may affect the patient’s ability to actuate the device
• Learning difficulties or cognitive impairment
• Inhaling too fast or too slow for the device
• Inappropriate device for the patient’s lifestyle

Errors with the health professional include:

• Not explaining to the patient how to use the device
• Not demonstrating the inhaler technique
• Not checking inhaler technique at every opportunity
• Inadequate assessment of the patient’s inspiratory effort to ensure the device is appropriate
• Inadequate assessment of the patient’s ability to use the device correctly

Evidence indicates that patients who express a preference for a particular device are more likely to use their inhaler correctly and are easier to teach correct inhaler technique (Lenney et al, 2000).

Inhaler Technique

Basically, there are 2 inhalation techniques for using inhaled

devices – slow and steady for MDIs, breath actuated devices and soft mist devices and quick ad deep for DPIs.

Inhaler technique –Meter Dose Inhaler

1. Remove the cap

2. Shake the inhaler

3. Breathe out gently away from the device

4. Put the mouthpiece in the mouth and at the start of inspiration press the canister down

5. Breathe in steadily and deeply

6. Hold the breath for 10 seconds or as long as possible

7. Wait a few seconds before repeating steps 2-6

8. Replace the cap

To increase the deposition of the drug in the lungs with the MDI, a spacer can be used. This will also make actuation of the device easier for the patient.

Inhaler technique using a spacer device

All spacers have static charge which attracts the medication to the spacer walls thus reducing the amount of medication available for deposition to the lungs. The static charge can be reduced by washing the spacer in warm soapy water, soaking it for a few minutes and letting the spacer to “dripdry”. This will last for 4 weeks and the spacer does not need to be washed more frequently unless the patient experiences a respiratory tract infection. Then it should be washed more frequently.

Spacers can be large Volumatic (eg Volumatic™) or small volume (eg Aerochamber™ or Free Breath spacer™). Spacers can used by using either the multiple breath technique (tidal breathing for 5-6 breaths) or the single breath technique (a single breath is inhaled after actuation of the device and the breath is held for 10 seconds). Spacer devices need to changed according to the manufacturer’s instructions.

Inhaler technique – Breath actuated devices

1. Shake the inhaler

2. Hold the inhaler upright and open the cap

3. Breathe out gently away from the device. Keep the inhaler upright

4. Put the mouthpiece in the mouth and close the lips and teeth around the mouthpiece taking care not to block the air holes on the top of the inhaler

5. Breathe in steadily through the mouthpiece and continue to inhaler when the medication is released

6. Hold the breath for about 10 seconds

7. After use hold the inhaler upright and close the cap

8. For a second dose, wait a few seconds before repeating steps 1-6.

Inhaler technique –Dry Powder devices

Each dry powder device (easyhaler, diskus, elipta, breezhaler, turbohaler, genuair) all have specific preparation prior to use. For the inhalation of the drug, the patient:

1. Breathes out fully away from the device

2. Puts the mouthpiece fully into the mouth closing the lips around the mouthpiece

3. Takes a breath in deeply and quickly

4. Holds the breath for 10 seconds

5. Repeats these steps if a second dose is required

Inhaler technique –Soft Mist Device

This device requires loading and priming by the pharmacist prior to dispensing to the patient. For daily use the patient:

1. Holds the soft mist inhaler upright with the cap closed

2. Turn the base in the direction of the red arrows until the inhaler clicks

3. Open the cap

4. Breathe out fully away from the device and

5. Close lips around the mouthpiece without covering the air vents.

6. Point the inhaler to the back of the throat

7. While taking a slow deep breath through the mouth, press the dose release button and continue to breath for as long as possible

8. Hold breath for 10 seconds or for as long as possible

Written instructions on inhaler technique are readily available for all inhalers which should be given to patients. Inhaler technique videos are available on www.asthma.ie or by sending a message to the Asthma Society of Ireland WhatsApp messaging service on 086 0590132. All inhalers have specific care and maintenance and patients need to be educated regarding this to ensure medication is delivered in its optimum state. Information regarding care and maintenance is provided by the manufacturers.

Conclusion

This article has reviewed the importance of assisting the patient in the appropriate choice of inhaler device to optimally manage their condition whilst considering the environmental impact. The concepts of inhaled medication and optimal inspiratory effort have been explored. Common errors in inhaler technique have been discussed. Finally, inhaler technique for MDI, breath actuated devices, soft mist inhalers and dry power devices has been addressed.

Useful Resource:

Scullion J., Fletcher M., 2016, Inhaler standards and competency document. UK Inhaler Group https:// www.ukinhalergroup.co.uk/uploads/ iYf51ixS/ukig-inhaler-standardsjanuary-2017.pdf

References available on request

Written by Ruth Morrow, Respiratory Nurse Specialist, Asthma Society of Ireland

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