Exhaled nitric oxide concentration upon acute exposure to moderate altitude

Abstract

The purpose of this study was to assess immediate changes in the partial pressure of nitric oxide (NO) in exhaled gas (PE NO ) in healthy trained subjects who were acutely exposed to moderate altitude. One group of nine and another group of 20 healthy subjects were exposed to an ambient pressure of 728 hPa (546 mmHg) corresponding to an altitude of 2800 m for 5 and 90 min, respectively, in an altitude chamber. PE NO was measured offline by sampling exhaled gas in tight metal foil bags at 5, 30, 60, and 90 min. A correction for increased expiratory flow rate due to gas density effects at altitude was performed (PE NO corr). PE NO was significantly decreased by 13-16%, while the fraction of NO in exhaled gas (FE NO) was increased by 16-19% compared to sea level. There was no significant change in PE NO corr after exposure to altitude for 5, 30, 60, and 90 min. We conclude that there was no change in PENO upon arrival at altitude after correcting for gas density effects on expiratory flow rate. Corrections for altitude effects must be done before comparing measurements performed at different altitudes when using measurements of FENO to monitor athletes who have asthma during training at altitude.

Exhaled nitric oxide after high‐intensity exercise at 2800 m altitude

“…Furthermore, PE NO was corrected for differences in expiratory flow rate between 180 and 2800 m (PE NOcorr ) due to differences in gas density as described by Caspersen et al . ().…”

“…Partial pressure of exhaled nitric oxide FE NO was converted to PE NO (mPa) to express the molar concentration of NO (PE NO =FE NO •(P B -P H2O ). Furthermore, PE NO was corrected for differences in expiratory flow rate between 180 and 2800 m (PE NOcorr ) due to differences in gas density as described by Caspersen et al (2013).…”

Electrochemical monitoring of bronchial inflammation in pediatric athletes: A prospective study

“…Monitoring the inflammation in various sports may be a valuable tool in diagnosing a wide range of diseases and to predict the imminence of exacerbation (i.e. asthma attack) (23)(24)(25)(26).…”

The effect of high altitude on nasal nitric oxide levels

“…Also, there are studies about genetic adaptation of highlanders to the hA, such as tibetans and Andeans [6,7,[11][12][13][14][15][16]. however, we have little data about the effect of hA on nnO levels and the change of nnO levels, during acclimatization has not been studied sufficiently.…”