Does consumption of ethanol distort measurements of exhaled nitric oxide?
BACKGROUND
Measuring FE(NO) is a novel and non-invasive way to monitor airway inflammation (e.g. asthma). This clinical study was designed to investigate whether drinking ethanol might distort FE(NO) measurements.


METHODS
Twenty healthy subjects drank 0.40 g ethanol/kg body weight in 15 min. Measurement of FE(NO) started approximately 30 min before drinking and at various times afterwards for 4 h post-dosing. Ethanol concentrations were determined in venous blood by gas chromatography and in end-exhaled breath by infra-red spectrometry.


RESULTS
The within subject standard deviation for determination of FE(NO) was 1.3 ppb, corresponding to a CV of 7.7%. The mean change in FE(NO) from pre-drinking levels during the 4h testing was statistically significant (P<0.001) according to repeated measures ANOVA. In absolute units the mean change was small, -2.01 and -1.94 ppb at 3 and 4h post-dosing, respectively (P<0.013, P<0.005).


CONCLUSIONS
FE(NO) measurements were reproducible even in subjects with moderate concentrations of ethanol in blood and breath. The small decrease in FE(NO) observed at 3 and 4 h post-drinking was less than the intra-subject variations in FE(NO) measurements. The breath-alcohol concentrations in this study exceed all other endogenous volatiles, thus making it unlikely that other substances in human breath will bias the FE(NO) measurements.
Jones
A Wayne
AW
Department of Forensic Toxicology, University Hospital, SE-581 85 Linköping, Sweden. wayne.jones@rmv.se
Fransson
Monika
M
Maldonado-Holmertz
Elisa
E
D000328:Adult; D000428:Alcohol Drinking; D000704:Analysis of Variance; D001249:Asthma / Q000175:diagnosis*; D001944:Breath Tests / Q000379:methods; D000431:Ethanol / Q000032:analysis* / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D009569:Nitric Oxide / Q000032:analysis* / Q000097:blood; D012119:Respiration / Q000187:drug effects
D009569:Nitric Oxide; D000431:Ethanol