Bronchodilators delivered by nebuliser versus inhalers for lung attacks of chronic obstructive pulmonary disease

Review question

When someone is suffering from a lung attack due to chronic obstructive pulmonary disease (COPD), are inhalers with a spacer as good as nebulisers?


Someone experiencing a lung attack suffers from shortness of breath because the airways are narrowed. Bronchodilators are a type of drug that helps to open these airways, but the best way to deliver them to the body is unknown. We searched for the best delivery device during lung attacks, focusing on whether there is a difference between wet nebulisers, which allow people to breathe in medicine as a mist using a mask or mouthpiece, compared with inhalers.

What evidence did we find?

We found eight studies including 250 participants in a search of the available studies up to 1 July 2016. All of the studies took place in a hospital.

What do the studies tell us?

The primary outcomes of the review showed no difference between the inhaler with a spacer and the nebuliser. However, in our secondary outcomes, we found some evidence that nebuliser treatment improves lung function more than inhalers with a spacer, but the quality and quantity of the data is limited. We found no difference between the therapies in terms of side effects or for reducing breathlessness. There are no studies available testing dry powder inhalation against a nebuliser.


Due to the low quality and quantity of the data, it is not clear whether nebulisers or inhalers with spacers are better for lung attacks. We found no difference between an inhaler with a spacer and the nebuliser in lung function after one hour or in unwanted side effects during lung attacks of COPD. The secondary outcome for lung function did favour nebulisers over inhalers with a spacer.

Authors' conclusions: 

There is a lack of evidence in favour of one mode of delivery over another for bronchodilators during exacerbations of COPD. We found no difference between nebulisers versus pMDI plus spacer regarding the primary outcomes of FEV1 at one hour and safety. For the secondary outcome 'change in FEV1 closest to one hour after dosing' during an exacerbation of COPD, we found a greater improvement in FEV1 when treating with nebulisers than with pMDI plus spacers.

A limited amount of data are available (eight studies involving 250 participants). These studies were difficult to pool, of low quality and did not provide enough evidence to favour one mode of delivery over another. No data of sufficient quality have been published comparing nebulisers versus DPIs in this setting. More studies are required to assess the optimal mode of delivery during exacerbations of COPD.

Read the full abstract...

Bronchodilators are a central component for treating exacerbations of chronic obstructive pulmonary disease (COPD) all over the world. Clinicians often use nebulisers as a mode of delivery, especially in the acute setting, and many patients seem to benefit from them. However, evidence supporting this choice from systematic analysis is sparse, and available data are frequently biased by the inclusion of asthma patients. Therefore, there is little or no formal guidance regarding the mode of delivery, which has led to a wide variation in practice between and within countries and even among doctors in the same hospital. We assessed the available randomised controlled trials (RCTs) to help guide practice in a more uniform way.


To compare the effects of nebulisers versus pressurised metered dose inhalers (pMDI) plus spacer or dry powder inhalers (DPI) in bronchodilator therapy for exacerbations of COPD.

Search strategy: 

We searched the Cochrane Airways Group Trial Register and reference lists of articles up to 1 July 2016.

Selection criteria: 

RCTs of both parallel and cross-over designs. We included RCTs during COPD exacerbations, whether measured during hospitalisation or in an outpatient setting. We excluded RCTs involving mechanically ventilated patients due to the different condition of both patients and airways in this setting.

Data collection and analysis: 

Two review authors independently assessed studies for inclusion, extracted data and assessed the risk of bias. We report results with 95% confidence intervals (CIs).

Main results: 

This review includes eight studies with a total of 250 participants comparing nebuliser versus pMDI plus spacer treatment. We identified no studies comparing DPI with nebulisers. We found two studies assessing the primary outcome of 'change in forced expiratory volume in one second (FEV1) one hour after dosing'. We could not pool these studies, but both showed a non-significant difference in favour of the nebuliser group, with similar frequencies of serious adverse events. For the secondary outcome, 'change in FEV1 closest to one hour after dosing': we found a significant difference of 83 ml (95% CI 10 to 156, P = 0.03) in favour of nebuliser treatment. For the secondary outcome of adverse events, we found a non-significant odds ratio of 1.65 (95% CI 0.42 to 6.48) in favour of the pMDI plus spacer group.