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FeNO Testing

Just a minute! Why can’t I see an instant FeNO result?

Testing a patient’s level of fractional exhaled nitric oxide (FeNO) is a valuable tool in asthma diagnosis and management so it’s important to know you can rely on the results.1

Last updated: September 2024

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Achieving this level of accuracy requires care, which is why the analysis phase requires about a minute to provide a result.

Nitric oxide (NO) is a gas. Measuring the concentration of the composition of gas is an exact science, looking at minute molecules – that’s why it’s measured in parts per billion. It makes sense that it’s also crucial to ensure the technology you choose gets it right and, when it’s done properly, that takes a minute.

FeNO measurement devices like NIOX® are built with a sensor, a piece of technology which measures the NO in the exhaled breath of the patient. These sensors must convert the gas concentration of the breath into electrical signals to produce a FeNO value.

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Just a minute! Why can’t I see an instant FeNO result?

How does it work?

After the patient exhales into the NIOX® device, any excess humidity in the sample is removed by the specially rifled tubing before the chamber inside is filled with the breath. NIOX® has a pump, which extracts the sample from the chamber so the breath can be flushed over the sensor.

The recommendations on FeNO testing published by the European Respiratory Society and the American Thoracic Society state that ambient NO should be scrubbed from the measurement.2 NIOX® takes care of that too, with ambient nitric oxide removed during the inhalation phase of every test. NIOX® also calculates a baseline measurement for added accuracy.

Once the baseline is established, the device analyses the signal curve for both the patient’s breath sample and the zero measurement. NIOX® technology ensures both curves are correct and that there is a good NO plateau. The device then puts all of this data together to calculate and display the FeNO level. Quite remarkably, it manages to perform all these vital steps in just 70 seconds – no mean feat!

What is FeNO Testing?

Fractional exhaled nitric oxide (FeNO) testing is a simple, non-invasive, and rapid point-of-care test to measure airway inflammation associated with Type 2 asthma.*

FeNO testing involves inhaling then exhaling through the device to measure a patient’s FeNO level and can be used on adults and children.**

FeNO testing is a quick and easy way to diagnose and manage asthma.*

* Alving K et al. Validation of a new portable exhaled nitric oxide analyzer, NIOX VERO®: randomized studies in asthma. Pulm Ther. 2017;3:207-218. ** NIOX®. Product Labelling Summary NIOX VERO®. 2023.

To ensure you always receive an accurate, reliable and reproducible result, NIOX® is designed to ensure these processes happen with precision.3,4 Achieving this level of accuracy requires care, which is why the analysis phase requires about a minute to provide a result. It’s a minute worth waiting for so why settle for anything less?

If you’d like to know more about NIOX® technology, book a personal demonstration. You can try the device and really see how these smart features add value to your asthma treatment plans. You can also see NIOX® on your desk with our virtual reality tool by clicking here.

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References:

  1. Czubaj-Kowal M et al. Relationship between air pollution and the concentration of nitric oxide in the exhaled air (feno) in 8–9-year-old school children in Krakow. International Journal of Environmental Research and Public Health. 2021;18(13):6690.
  2. American Thoracic Society; European Respiratory Society. ATS/ERS recommendations for standardized procedures for the online and offline measurement of exhaled lower respiratory nitric oxide and nasal nitric oxide, 2005. Am J Respir Crit Care Med. 2005;171(8):912-30.
  3. Alving K et al. Validation of a new portable exhaled nitric oxide analyzer, NIOX VERO®: randomized studies in asthma. Pulm Ther. 2017;3:207-218.
  4. Gao J et al. Association between fractional exhaled nitric oxide, sputum induction and peripheral blood eosinophil in uncontrolled asthma. Allergy, Asthma & Clinical Immunology. 2018;1.

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