Comparability of a hand-held nitric oxide analyser with online and offline chemiluminescence-based nitric oxide measurement.
Practicability is crucial for successful implementation of fractional exhaled nitric oxide (FeNO) measurement into asthma management. The study aimed at comparing a conventional chemiluminescence NO analyser (EcoMedics) with a hand-held device (NIOX MINO) and offline FeNO measurement using a commercially available system in an unselected cohort of children aged 6-16 yr. A secondary objective was to confirm FeNO stability over time in 15 samples from adult volunteers obtained using the offline system. Sixty-six children (mean +/- s.d. age 11.8 +/- 3.0 yr) underwent single breath FeNO measurement in triplets with each device. Offline collected FeNO was measured after offline breath collection into a Mylar balloon and subsequent analysis using the chemiluminescence NO analyser. Variability and between-method agreement were assessed, and stability over time within the Mylar balloons was tested by repeated hourly measurements. FeNO levels ranged from 2 to 113 p.p.b. Intra-class correlation was excellent (r = 0.98, p < 0.001 for each pair). Bland-Altman plots and back-transformation of logarithmic mean differences revealed fair agreement between methods. Stability over time was confirmed over 10 h both at room temperature and when stored under cooling conditions. FeNO values obtained using the chemiluminescence NO analyser, the portable NIOX MINO system and the offline collection technique show between-method agreement within clinically acceptable range.
Schiller
Barbara
B
Division of Pediatric Intensive Care and Pulmonology, University Children's Hospital of Basel, Basel, Switzerland.
Hammer
Juerg
J
Barben
Juerg
J
Trachsel
Daniel
D
D000293:Adolescent; D001249:Asthma / Q000503:physiopathology*; D001944:Breath Tests / Q000295:instrumentation* / Q000379:methods; D002648:Child; D004563:Electrochemistry / Q000379:methods; D004867:Equipment Design; D045853:Exhalation; D005260:Female; D006801:Humans; D008163:Luminescent Measurements / Q000295:instrumentation* / Q000379:methods; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods; D009569:Nitric Oxide / Q000032:analysis*; D012016:Reference Values; D015203:Reproducibility of Results
D009569:Nitric Oxide