Key message: Nebulisers don’t all perform the same. Some newer types such as adaptive aerosol delivery and vibrating mesh technology have advantages over conventional systems including significantly shorter treatment time
Nebulisers are devices that allow medicines to be breathed in as a mist. People with cystic fibrosis (CF) are amongst those living with chronic conditions who use them to take medicines which help control their symptoms. Taking medicines this way may take a few minutes or as much as forty minutes each time and nebulised treatment has been found to significantly add to the burden of treatment for people with CF.
There are lots of different types of nebulisers but which work best? A team from the Cochrane Cystic Fibrosis and Genetic Disorders Group has now done the first systematic review to look at the evidence on this. They wanted to know how effective and safe different types of nebulisers are, what impact they have in terms of treatment burden and how well people using them follow their prescribed treatment regime.
The nebuliser systems being compared were conventional systems, adaptive aerosol delivery (ADD) with and without vibrating mesh technology (VMT), VMT systems and ultrasonic nebuliser systems. The medicines were tobramycin, colistin, dornase alfa, hypertonic sodium chloride and other aerosolised medicines.
They found twenty studies to include, in which 1936 children and adults with CF had taken part, and results from all but two could be combined.
What did they find?
- Nebulisers using newer technologies such as AAD or VMT deliver the medicine faster and get more of it into the lungs than conventional systems
- The newer systems are safe when used with the correct priming dose, which may be different from the dose used in conventional systems
- People seem to stick to the treatment regime as well or better using the newer types of nebulisers
- Some systems using VMT may go wrong more often
How good was the evidence?
There are a number of gaps. There were only a few studies available for each type of system and medicine and some combinations (of system and medicine) where no evidence was found
In almost all the studies details of the way the studies were designed and run (such as how people were randomized to their treatment groups) were not described
Four studies were available only as abstracts and supply only limited detail of methods and results. The authors have been asked for more information but this is currently missing from the review; if provided it can be included in a later version of the review. Three other studies did not report on missing data. Missing data is a source of bias in reviews and we know that negative or unfavourable results are more likely to remain unpublished
What should future trials consider?
As is so often the case, the review team have identified a need for future trials to explore outcomes which matter to patients. Specifically they highlight the need for evidence on the impact of newer nebuliser systems on quality of life and burden of treatment for people with CF, as well as on safe and effective dosing levels, clinical outcomes such as hospital admissions and the need for antibiotics and an economic evaluation of their use.
If you are someone with CF using nebulisers, what matters most to you and what would you like to see researchers investigating? You might be interested in the comments left below one of our earlier blogs (here), which was about a review on antibiotics for COPD but prompted interesting responses from Oli Rayner, who has CF, and Nikki Jahnke, the Managing Editor of the Cochrane Cystic Fibrosis and Genetic Disorders Group.
Daniels T, Mills N, Whitaker P. Nebuliser systems for drug delivery in cystic fibrosis. Cochrane Database of Systematic Reviews 2013, Issue 4. Art. No.: CD007639. DOI: 10.1002/14651858.CD007639.pub2.