RT Journal Article
SR Electronic
T1 Simultaneous sulfur hexafluoride and nitrogen multiple-breath washout (MBW) to examine inherent differences in MBW outcomes
JF ERJ Open Research
JO erjor
FD European Respiratory Society
SP 00234-2018
DO 10.1183/23120541.00234-2018
VO 5
IS 4
A1 Katie J. Bayfield
A1 Alex Horsley
A1 Eric Alton
A1 Samantha Irving
A1 Andrew Bush
A1 Jane C. Davies
YR 2019
UL http://openres.ersjournals.com/content/5/4/00234-2018.abstract
AB Multiple-breath washout (MBW) can be performed with different gases (sulfur hexafluoride (SF6­) and nitrogen (N2)) and different devices, all of which give discrepant results. This study aimed to confirm previously reported differences and explore factors influencing discrepant results; equipment factors or the physical properties of gases used.Methods Healthy controls (HCs) and participants with cystic fibrosis (CF) completed MBW trials on two commercially available devices (Exhalyzer D (N2) and Innocor (SF6)). Simultaneous washout of both gases at the same time on the commercial equipment and simultaneous washouts using a respiratory mass spectrometer (RMS) were completed in subsets. Primary outcomes were lung clearance index (LCI), breath number and time required to washout.Results Breath number was higher with N2 washout than SF6 in both HCs and patients with CF, whether washouts were completed individually or simultaneously. The difference was greater in more advanced disease, largely caused by differences in the final part of the washout. Results from commercial devices were similar to those obtained with the RMS.Conclusions N2 MBW results were higher than SF6 MBW, with some of the largest differences reported to date being observed. The biggest impact was at the end of the washout and this was even the case when gases were washed out simultaneously. N2 and SF6 MBW results are inherently different and should be considered as independent measurements.Inherent differences in simultaneous SF6 and N2 washout on the mass spectrometer show why results are never comparable http://bit.ly/34k52Oo