An introduction to the factors that influence spacer performance in everyday respiratory care.
Spacers are a familiar part of asthma and chronic obstructive pulmonary disease (COPD) care. Their effectiveness, however, involves more than the device alone. The medication being delivered, the way a person breathes and the technique they use all play a part.
In this monthly series, we’ll explore these factors and their relevance to healthcare professionals. We begin with three connected topics: inhalation technique, device design and the interpretation of research evidence.
Understanding the role of spacers
Valved holding chambers, commonly called spacers, are used with pressurised metered dose inhalers, or “puffers”. They help reduce the need to coordinate pressing the inhaler with breathing in and can reduce the amount of medication deposited in the mouth and throat.
Understanding their performance means considering how the device, medication and user work together. A spacer’s characteristics matter, but so does the support a person receives to use it correctly.
Technique in everyday use
Preparing an inhaler, releasing the medication and breathing through a spacer can all influence medication delivery. Even when someone has received initial instruction, correct technique may need reinforcement.
Practical demonstration and repeated assessment are therefore important parts of inhaler education. Asking someone to show how they use their device gives healthcare professionals an opportunity to identify difficulties, provide guidance and check understanding.
This makes technique an ongoing conversation within respiratory care.
The contribution of device design
Spacer design can also influence performance. Valve characteristics and antistatic properties affect how medication moves through the chamber, while some devices include features intended to guide inhalation.
These features need to be considered alongside the evidence supporting them. An improvement in technique or laboratory performance does not necessarily establish an improvement in clinical outcomes. Findings for one spacer model also cannot automatically be applied to another.
Making sense of the evidence
Laboratory testing provides useful information about medication delivery under controlled conditions. However, results can be influenced by the medication tested, the breathing pattern simulated and the methods used.
Considering these details helps healthcare professionals interpret comparisons and understand what a study can tell them about everyday use.
Together, these topics provide a foundation for looking beyond individual product features and considering spacer use more broadly: the device, the medication, the person and the education that supports them.
Reference
Hall, G. (2026). Spacer effectiveness: Review of evidence and identification of key messages. Synergy Health Solutions. August 2026.