Assessment of the impact of collection temperature and sampler design on the measurement of exhaled breath condensate pH in healthy horses.
The pH measurement of exhaled breath condensate (EBC) may provide a non-invasive method of assessing the lower airways of horses but the methodology used may influence findings. The aim of this study was to investigate the effect of two sampling devices and three methods of condensation surface cooling (ethanol slush, -100°C; dry ice, -75°C; water ice, 0°C) on EBC pH. Each method was tested 30 times using six healthy ponies. Sample pH was determined before and after de-aeration with argon for 10 min. Sampler design was found to significantly affect pH. Samples collected as a liquid had a significantly higher pH than samples frozen during collection (P<0.05). De-aeration resulted in significantly higher pH (P<0.05) with less variation. This study has shown that device design and condensation surface temperature will influence EBC pH, which will prevent a direct comparison of results when different methodologies are used.
Weipers Centre for Equine Welfare, School of Veterinary Medicine, College of Medicine, Veterinary Medicine and Life Sciences, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK.
Andrew G
AG
Whittaker
Sandy
S
Love
Timothy D H
TD
Parkin
Marco
M
Duz
Michael
M
Cathcart
Kristopher J
KJ
Hughes
D000818:Animals; D001944:Breath Tests / Q000295:instrumentation*; D045853:Exhalation; D006736:Horses / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D012137:Respiratory System / Q000378:metabolism*; D013048:Specimen Handling / Q000295:instrumentation*; D013696:Temperature