Fractional Exhaled Nitric Oxide (FeNO)

What is it?

FeNO devices are a novel medical technology used to aid in the diagnosis of asthma. FeNO measures 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 have 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. The toolkit is open for anyone to access.

What are the benefits?

  • FeNO can improve patient care and outcomes through aiding more accurate and effective diagnosis of asthma.
  • FeNO can be used to confirm diagnosis improving misdiagnosis rates for asthma and leading to more appropriate referral to secondary care
  • The possibility of using FeNO for dose adjustments and monitoring purposes could result in a reduction in inappropriate inhaler prescribing.
  • The simplicity of FeNO testing means that anyone can use a FeNO device. This would reduce dependency on GPs within primary care as FeNO testing could be conducted by a practice nurse or other healthcare professional.
  • FeNO increases patient understanding of their condition as they can relate to their FeNO score.

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