Inhaler technique is an essential skill for patients and nurses to ensure optimum and accurate delivery of medication to the lungs. Ever since the development of the metered dose inhaler (MDI) 40 years ago, errors have been reported with technique.¹

Over the years, multiple devices have been developed in an attempt to overcome these errors and improve drug deposition to the lungs. Both the GOLD (2017) and GINA (2016) guidelines strongly recommend educating, assessing and reviewing the patient’s inhaler technique at every opportunity.^2,3 This article seeks to explore issues with inhaler technique including common errors and the different techniques for MDIs, dry powder devices (DPIs), breath actuate devices and soft mist inhalers. 

Inhaled medications

Inhaled medications are essential for treating asthma and COPD, among other respiratory conditions such as fibrosis. The big advantage of using inhaled medication is that the drug reaches 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 recent systematic review of inhaler technique involving 54,354 adults and children with either asthma or COPD investigated the extent and prevalence of inhaler use.¹ 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.¹ 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 it can be confusing for patients if they are on different devices. 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 inhaled devices on the market that can be used in combination. 

Good inhaler technique is essential:

• To optimise drug deposition into the lungs

• To manage treatment failure

• To improve symptoms

• To prevent inappropriate escalation of treatment

• To avoid side effects, such as hoarseness or dysphonia.

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, increased costs, and inappropriate escalation of treatment.⁴ In COPD, poor inhaler technique can lead to poorly controlled COPD. In a study by Rogliani et al 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.⁵

Types of inhaled medication

Basically, there are five ways to deliver inhaled medication: aerosol devices, breath activated devices, DPIs, soft mist inhalers, 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.⁶

The drug dose stated on the label is not the dose that is actually 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

A number of issues need to be considered when deciding on the appropriate device for a patient. Experience and research has shown that involving the patient in choosing the device aids better adherence.⁷ 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 take into account. 

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 can impact on a patient’s ability or willingness to use a device. 

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 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 in side effects as the drug is deposited in the mouth and oropharynx. 

Starting inhaled medication – 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 about storage and maintenance of inhaler device.

Common errors in inhaler technique

The errors with inhaler technique can be categorised as: errors with the device, errors with patient, and errors with the health professional.⁸ Cultural barriers also exist with inhaler use. In some populations, the use of an inhaler is seen as improper or impolite, and oral medications may be preferred.⁹

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.⁶

Inhaler technique

Basically, there are two inhalation techniques for using inhaled devices – slow and steady for MDIs, breath actuated devices and soft mist devices, and quick and deep for DPIs .

Meter dose inhaler – step by step

1. Remove the cap

2. Shake the inhaler

3. Breathe out gently

4. Put the mouthpiece in the mouth and at the start of inspiration and 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 two to six

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 ‘drip-dry’. This will last for four weeks and the spacer does not need to be washed more frequently.

Spacers can be large volume (eg. Volumatic) or small volume (eg. Aerochamber or Free Breath spacer). Spacers can be used by either the multiple breath technique (tidal breathing for five to six 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 be changed according to the manufacturer’s instructions. 

Breath actuated devices – step by step

1. Shake the inhaler

2. Hold the inhaler upright and open the cap

3. Breathe out gently. Keep 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 inhale 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 one to six.

Dry powder devices

Each dry powder device (Diskus, Elipta, Breezhaler, Turbohaler, Genuair) all have specific instructions 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.

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. Turns the base in the direction of the red arrows until the inhaler clicks

3. Opens the cap

4. Breathes out fully and closes lips around the mouthpiece without covering air vents 

5. Points the inhaler to back of the throat

6. While taking a slow deep breath through the mouth, presses the dose release button and continues to breathe for as long as possible

7. Holds 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. All inhalers have specific care and maintenance and patients need to be educated about this to ensure medication is delivered in its optimum state. Information with regard to care and maintenance is provided by the manufacturers.

Conclusion

This article has reviewed the importance of choosing the appropriate inhaler device for the patient. 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 powder devices has been addressed.

References 

1. Sanchis J., Gich, I. & Pedersen, S. (2016) Systematic review of errors in inhaler use: Has patient technique improved over time? Chest, 150(2), 394-406.
2. Global Strategy for the Diagnosis, Management and Prevention of COPD, Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017. Available from: http://www.goldcopd.org/.
3. Global Initiative for Asthma, 2016, Global Strategy for Asthma Management and Prevention.
4. Al-Jahdali, H., Ahmed, A., Al-Harbi, A., Khan, M., Baharoon, S., Bin Salih, S., Halwani, R. & Al-Muhsen, S., 2013, Improper inhaler technique is associated with poor asthma control and frequent emergency department visits. Allergy, Asthma, and Clinical Immunology: Official Journal of the Canadian Society of Allergy and Clinical Immunology, 9(1), 8-8.
5. Rogliani, P., Calzetta, L., Coppola, A., Cavalli, F., Ora, J., Puxeddu, E., Matera, M.G. & Cazzola, M. 2017, Optimizing drug delivery in COPD: The role of inhaler devices. Respiratory Medicine, 124, 6-14.Scullion J., Fletcher M., 2016, Inhaler standards and competency document. UK Inhaler Group
6. Education for Health, 2015, Simply devices
7. Lenney, J., Innes, J.A. & Crompton, G.K. (2000) Inappropriate inhaler use: assessment of use and patient preference of seven inhalation devices. Respiratory Medicine, 94(5), 496-500.
8. Price, D., Bosnic-Anticevich, S., Briggs, A., Chrystyn, H., Rand, C., Scheuch, G. & Bousquet, J. 2012, Inhaler competence in asthma: Common errors, barriers to use and recommended solutions. Respiratory Medicine, 107(1), 37-46.
9. Griffiths, C., Foster, G., Barnes, N, Eldridge, S., Tate, H., Begum, S., et al., 2004, Specialist nurse intervention to reduce unscheduled asthma care in a deprived multi-ethnic area: the east London randomised controlled trial for high risk asthma (ELECTRA) BMJ, 328 (7432)  p. 144