BACKGROUND Nitric oxide is released from pulmonary endothelial cells and contributes to the low pulmonary vascular resistance. The resistance pulmonary arteries are in close anatomical proximity to membranous airways, so it is likely that some pulmonary endothelial nitric oxide will enter the airspace to allow its measurement in the exhaled breath. METHODS Exhaled air was collected from a sin...

Nitric oxide (NO) is produced at different sites in the human airways and may have several physiological effects. Orally-produced NO seems to contribute to the levels found in exhaled air. Autoinhalation of nasal NO increases oxygenation and reduces pulmonary artery pressure in humans. The aim of this study was to measure the concentration and output of NO during nasal, oral and tracheal contro...

There is evidence that genetic factors affect nitric oxide formation and that sequence variants in the nitric oxide synthase genes contribute to the observed variance of nitric oxide levels in exhaled air (fraction of expired nitric oxide, FENO) in subjects with asthma. We identified a strong association between a known functional NOS3 missense sequence variant in the endothelial nitric oxide g...

The concentration of nitric oxide in exhaled air, a marker of airway inflammation, depends critically on the flow of exhalation. Therefore, the aim of this study was to determine the effect of varying the flow on end-expiratory NO concentration and NO output in children with asthma or cystic fibrosis (CF) and in healthy children. Nineteen children with stable asthma, 10 with CF, and 20 healthy ...

1. Wang Z, Pianosi P, Keogh K, et al. The Clinical Utility of Fractional Exhaled Nitric Oxide (FeNO) in Asthma Management. Agency for Healthcare Research and Quality (US); 2017. Comparative Effectiveness Review Number 197. doi:10.23970/AHRQEPCCER197 CrossRef Google Scholar

Considerable confusion exists about the clinical use of exhaled nitric oxide measurement in general, and its bronchial and alveolar contributions in particular, for instance in response to treatment. An additional effect needs to be factored in when considering the degree of alveolar nitric oxide abnormality and its response to therapeutic interventions that may or may not be targeted to the lu...

Airways inflammation has been associated with increased nitric oxide (NO) in the exhaled breath. It was, therefore, questioned whether exhaled NO could act as an indicator of the severity of airways inflammation in the chronic suppurative lung diseases cystic fibrosis (CF) and bronchiectasis. NO levels in a single exhalation were measured using a chemiluminescence analyser. Thirty-six patients ...