alexa Effect of measurement conditions on measured levels of peak exhaled nitric oxide.
Materials Science

Materials Science

Journal of Nanomedicine & Nanotechnology

Author(s): Byrnes CA, Dinarevic S, Busst CA, Shinebourne EA, Bush A

Abstract Share this page

Abstract BACKGROUND: It is possible to measure nitric oxide (NO) levels in exhaled air. The absolute concentrations of exhaled NO obtained by separate workers in similar patient groups and normal subjects with apparently similar techniques have been very different. A study was undertaken to determine whether changes in measurement conditions alter the concentration of exhaled NO. METHOD: NO concentrations measured by a chemiluminescence analyser (Dasibi Environmental Corporation) and carbon dioxide (CO2) measured by a Morgan capnograph were analysed in single exhalations from total lung capacity in healthy volunteers (mean age 35.9 years). Ten subjects performed five exhalations at four different expiratory flow rates, at four different expiratory mouth pressures, and before and after drinking hot (n = 5) or cold (n = 5) water. Three subjects performed five exhalations on a day of high background NO (mean NO level 134 ppb) before and after a set of five exhalations made while both the subject and analysers were sampling from a low NO/NO-free reservoir system. RESULTS: The mean peak concentration of NO decreased by 35 ppb (95\% CI 25.7 to 43.4) from a mean (SE) of 79.0 (15.5) ppb at an expiratory flow rate of 250 ml/min to 54.1 (10.7) ppb at 1100 ml/min. The mean peak concentration of NO did not change significantly with change in mouth pressure. The mean (SE) peak NO concentration decreased from 94.4 (20.8) ppb to 70.8 (16.5) ppb (p = 0.002, 95\% CI 12.9 to 33.1) with water consumption. The mean NO concentration with machine and subject sampling from the low NO reservoir was 123.1 (19.4) ppb, an increase from results obtained before (81.9 (10.2) ppb, p = 0.001, 95\% CI -19.9 to -62.7) and after (94.2 (18.3) ppb, p = 0.017, 95\% CI 6.0 to 51.8) sampling with high ambient NO. CONCLUSIONS: The measurement of exhaled NO must be performed in a carefully standardised manner to enable different teams of investigators to compare results.
This article was published in Thorax and referenced in Journal of Nanomedicine & Nanotechnology

Recommended Conferences

  • Nano Congress for Next Generation
    August 31-September 01, 2017 Brussels,Belgium
  • Graphene & 2D Materials
    September 14-15, 2017 Edinburgh, Scotland
  • Graphene & 2D Materials
    November 6-7, 2017 Frankfurt, Germany
  • World Congress on Nanoscience and Nano Technology
    October 16-17, 2017 Dubai, UAE
  • World Medical Nanotechnology Congress
    October 18-19, 2017 Osaka, Japan
  • Nanoscienceand Molecular Nanotechnology
    Nov 06-08, 2017 Frankfurt, Germany
Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version