RT Journal Article
SR Electronic
T1 Plethysmography Derived Gas Trapping Lacks Utility in Predicting Response to Bronchial Thermoplasty
JF ERJ Open Research
JO erjor
FD European Respiratory Society
SP 00690-2021
DO 10.1183/23120541.00690-2021
A1 Ashwin Rajan
A1 Kim Bennetts
A1 David Langton
YR 2022
UL http://openres.ersjournals.com/content/early/2022/03/10/23120541.00690-2021.abstract
AB There is a paucity of literature on measurable baseline parameters predicting response and guiding selection for bronchial thermoplasty (BT). This study examines whether baseline gas trapping, as assessed by plethysmography is associated with a response to BT at 12 months.Forty three consecutive patients with severe asthma (57.6±13.3 years) were evaluated at baseline and 12 months post BT. Data collected at both time points included spirometry, body plethysmography, and four clinical outcome measures, namely Asthma Control Questionnaire score (ACQ), annual exacerbation frequency, maintenance oral corticosteroid requirement and short acting beta agonist use).At baseline, participants had severe airflow obstruction (FEV1 49.1±15.8%) with marked gas trapping (RV 150.3±40.8%, RV/TLC 51.3±10.5%), poor symptom control (ACQ 3.3±1.0) and frequent exacerbations (4 (8)). Twelve months after BT, significant improvements were observed in all four clinical outcome measures. However, baseline RV and RV/TLC were not significantly associated with changes in ACQ nor any other clinical outcome measure, and changes in RV and RV/TLC did not significantly correlate with a change in any clinical outcome measure.Plethysmography derived gas trapping does not demonstrate utility in predicting response and guiding selection for BT. An improvement in gas trapping was not associated with positive clinical outcomes, suggesting this may not the dominant mode of action of BT in generating clinical improvement.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Dr. Rajan has nothing to disclose.Conflict of interest: Dr. Bennetts has nothing to disclose.Conflict of interest: Dr. Langton has nothing to disclose.