Fractional Exhaled Nitric Oxide (FeNO)

What is it?

FeNO devices are a novel medical technology used to aid in the diagnosis of asthma. FeNO devices measure fractional exhaled nitric oxide in the breath of patients. Nitric oxide is a biomarker for asthma which provides an indication of the level of inflammation in the lungs. FeNO testing produces a FeNO score which gives a value to the level of inflammation and can therefore be used to aid in the diagnosis of asthma. Although FeNO is primarily a diagnostic tool, it has an additional use in the ongoing monitoring of chronic asthma.

Wessex Academic Health Science Network has created a FeNO rapid uptake product delivery toolkit, which provides downloadable tools and resources to support NHS organisations with the adoption and implementation of FeNO testing to improve the outcome for people with suspected and confirmed asthma. Anyone can access the toolkit and it also contains case studies of best practice identified through the programme.

The toolkit has a dedicated ‘help with your business case’ page filled with resources to support a strategic case for investing in FeNO testing. This includes a ‘Case for Change Template’ for clinical teams looking to implement FeNO testing at scale, and an ‘Interactive Data Dashboard’ to identify the impact and cost associated with asthma across clinical commissioning groups in England and also estimates the cost of procuring FeNO equipment.

A patient leaflet has been developed by the FeNO Rapid Uptake Product Working Group to explain what FeNO testing is to patients, its importance, how the test is performed and ways to prepare for it. It is important that patients have a good understanding of what to expect from their FeNO test appointment. The leaflet – Fractional Exhaled Nitric Oxide (FeNO): Your asthma inflammation test explained also sign-posts patients to other relevant patient information resources. This includes the FeNO patient video that has been collaboratively produced with Asthma UK and is available on their ‘tests to diagnose and monitor asthma’ webpage.

What are the benefits?

  • Improved accuracy of diagnosis forpatients suspected of having asthma
  • Improved effectiveness of patient care through better understanding of an individual’s condition
  • Improved patient outcomes, reducing the risk of exacerbations and admissions to hospital
  • Reduction in inappropriate prescribing, including corticosteroid prescribing
  • Reduction in the number of inappropriate referrals to secondary care clinics.

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