Validation Study of Fractional Exhaled Nitric Oxide Measurements Using a Handheld Monitoring Device

Abstract

We tested reproducibility of exhaled nitric oxide (FE_NO) and inter-operator handling when measured with a handheld device, NIOX MINO®. We enrolled 20 volunteers using a priori goals of acceptable reproducibility to be mean within-subject standard deviation less than 3 parts per billion (ppb) for FE_NO measurements less than 30 ppb, and mean coefficient of variation less than 10% for FE_NO measurements more than 30 ppb. Seventeen subjects with measurements less than 30 ppb displayed a mean standard deviation of 1.15, and 3 subjects with FE_NO more than 30 ppb had a mean coefficient of variation of 2.4%. We conclude that NIOX MINO demonstrates excellent reproducibility for all ranges of FE_NO.

Keywords:

• asthma
• exhaled nitric oxide
• airway inflammation
• point of care