Tessa Davis. Are nebulisers or spacers better for managing acute asthma?, Don't Forget the Bubbles, 2013. Available at:
This Cochrane review was published this week and here’s my summary.
This review looks at the question:
Which is better for the delivery of salbutamol in acute asthma – spacers or nebulisers?
Why is this review useful?
It’s useful because, in my experience, different hospitals have different practices with regards to the initial management of asthma in PED. In my previous hospital we gave 3 back-to-back salbutamol nebulisers (2.5mg or 5mg depending on the age/size). In my current hospital we give 3 x 20 minutely salbutamol inhalers.
What type of patients were included?
The studies included children being managed in ED, or in the community, wih acute asthma.
People with life-threatening asthma were excluded.
How many patients were included?
This review looked at 39 studies which included 1897 children. The review also looked at the evidence in adults.
What were the outcomes?
Primary outcomes: admission to hospital; duration of inpatient hospital stay.
Secondary outcomes: time in ED; change in respiratory rate; blood gases; pulse rate; tremor; symptom score; lung function; use of steroids; relapse rates.
What were the findings for these outcomes in ED?
There was no significant benefit in using nebulisers rather than spacers to deliver beta agonists to prevent hospital admission. And, the time spent in ED was significantly shorter (mean 33 mins) with spacers.
Pulse rate after treatment was significantly lower in children who received treatment via a spacer and development of tremor was more common in children who received nebulised treatment.
There was no difference in lung function or oxygen saturation.
Other points to note…
The authors acknowledge the uncertainty of choosing the correct dose. The studies generally rely on titrating the treatment to the response of the patient and repeating doses as necessary. This is good advice for real life.
The type of spacer did not affect the outcome.
The studies compared inhalers to separate nebulisers (not continuous). In practice, many hospitals use continuous nebulisers which is thought to be more effective than separate nebuliserss as it avoids rebound bronchoconstriction.
“Metered-dose inhalers with a spacer can perform at least as well as nebulisation in delivering beta-agonists in children with acute asthma”
Salbutamol has systemic side effects – tremor and increased pulse rate were more common when using nebulisers.