Is the “instant flow” option on the NIOX® analyser needed?

Malik, G.; Turner, S.W.

doi:10.1016/j.medengphy.2006.02.002

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Volume 29, Issue 1 , Pages 72-75, January 2007

Is the “instant flow” option on the NIOX^® analyser needed?

Department of Child Health, Royal Aberdeen Children's Hospital, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZG, United Kingdom

Received 12 November 2005; received in revised form 25 January 2006; accepted 1 February 2006. published online 13 March 2006.

Abstract

Asthmatics have increased gaseous nitric oxide in their exhaled breath. Measurements of the fraction of nitric oxide in exhaled breath (FE_NO) are used for the diagnosis and management of asthma. One analyser (the NIOX^® chemiluminescence analyser) has a feature (restriction of instant flow, IF) which we suspected was responsible for reducing the success rate for obtaining FE_NO measurements whilst not affecting the measurement itself. In a study involving 38 children, median age 10 years, we observed that FE_NO values taken in the same individual with and without IF restriction did not differ. We also observed that the success in obtaining a FE_NO measurement was higher (57%) when IF was not restricted and was lower (41%) when IF was restricted, p=0.002. Our findings do not support the use of restriction of IF on the NIOX^® analyser.