PT  - JOURNAL ARTICLE
AU  - Jenny Jagers
AU  - Michael Ji
AU  - Malcolm Johnson
AU  - Eric Wilde
AU  - Paul Easton
TI  - Inhaled vilanterol trifenatate/fluticasone furoate increases maximum diaphragm contraction in severe COPD
DP  - 2014 Sep 01
TA  - European Respiratory Journal
PG  - P3538
VI  - 44
IP  - Suppl 58
4099  - http://erj.ersjournals.com/content/44/Suppl_58/P3538.short
4100  - http://erj.ersjournals.com/content/44/Suppl_58/P3538.full
SO  - Eur Respir J2014 Sep 01; 44
AB  - Inhaled vilanterol trifenatate/fluticasone furoate (VFF), an ultra long acting beta2 agonist/ICS combination (Relvar) may change respiratory muscle activation and diaphragm contractility. Beta agonist effects on respiratory muscle activity have been shown in normal mammals and COPD patients (Resp Phys 2008 161:253-60,Chest 2010 137:558-65). Magnetic supra maximal phrenic nerve stimulation (MagStim) was utilized to assess diaphragm contraction via measurement of mouth pressure. 6 patients with severe COPD (mean FEV1 0.68), very minimally reversible (no change in FRC, IC or lung volumes) were studied before and 2 hrs after 2 puffs of VFF while breathing quietly, recording mouth pressure, and airflow through a pneumotach. MagStim was discharged at FRC (end expiratory zero airflow) and at selected points in inspiration and expiration, unanticipated by the subject. For all subjects, pressure from maximum diaphragm contraction by MagStim increased significantly after VFF (p<0.01). Similarly at matching points during the breathing cycle, lengths shorter than FRC, maximal contraction pressure increased after VFF (p<0.01). In severe COPD subjects, diaphragm contraction at matching lengths is increased after vilanterol trifenatate/fluticasone furoate (Relvar).