Which are better – spacers or nebulizers?

Take a look at this recent Cochrane review.

Cates, C.J., Welsh, E.J. and Rowe, B.H., 2013. Holding chambers (spacers) versus nebulisers for beta‐agonist treatment of acute asthma. Cochrane Database of Systematic Reviews (9).

It looks at the question Are spacers or nebulisers better in managing acute asthma?

Why is this review useful?

In my experience, different hospitals handle asthma differently. 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 via spacer.

What type of patients were included?

The studies included children being managed in the ED or in the community with acute asthma.

Children with life-threatening asthma were excluded.

How many patients were included?

This review examined 39 studies, including 1897 children.  It also looked at the evidence for the use of spacers 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?

There was no significant benefit in using nebulisers rather than spacers to deliver beta agonists in preventing hospital admission. 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 the 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 in selecting the appropriate salbutamol dose.  The studies generally rely on titrating the treatment to the patient’s response 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 are thought to be more effective than separate nebulisers as they avoid rebound bronchoconstriction.

Bottom line

Metered-dose inhalers with a spacer can perform at least as well as nebulisers when delivering beta-agonists in children with acute asthma

Salbutamol does have systemic side effects – tremor and increased pulse rate were more common when using nebulisers