TY - JOUR T1 - Expiratory muscle activity and nasal expiratory pressure during reverse sniff JF - European Respiratory Journal JO - Eur Respir J VL - 40 IS - Suppl 56 SP - P3519 AU - Tsuyoshi Ichikawa AU - Masanori Yokoba AU - Naohito Ishii AU - Akira Takakura AU - Atsuhiko Matsunaga AU - Masahiko Kimura AU - Tadashi Abe AU - Noriyuki Masuda AU - Paul Easton AU - Masato Katagiri Y1 - 2012/09/01 UR - http://erj.ersjournals.com/content/40/Suppl_56/P3519.abstract N2 - The evaluation of expiratory muscle strength is of clinical importance in patients with neuromuscular respiratory disease. Maximal expiratory pressure (MEP) has achieved wide acceptance as a simple non-invasive measurement of expiratory muscle strength. However, MEP measurement is difficult for neuromuscular disease patients. In this study, we measured expiratory muscle activity during reverse sniff, a maneuver akin to “blowing your nose”, and we analyzed the relationship between expiratory muscle activity and reverse sniff nasal expiratory pressure (RSNEP).In 5 healthy subjects, mean age 21.2 yrs, weight 69.2 kg, height 176.6 cm, we inserted fine wire electrodes into transversus abdominis muscle (TA) using high-resolution ultrasound. RSNEP was measured through a catheter that occluded one nostril, while the contralateral nostril remained open. Subjects performed short, sharp, maximum and variable intensity of reverse sniff, beginning from FRC while standing. TA EMG activity was expressed as percent of maximum EMG (%EMGmax) throughout respiratory and non-respiratory maneuvers.Mean MEP was 80.8±0.6 cmH2O. Mean maximum RSNEP was 34.9±18.7 cmH2O, and mean TA EMG activity at maximum RSNEP was 73.9±23.6 %EMGmax. TA EMG activity increased with stepwise increments in RSNEP. In every subject, the linear relationship between RSNEP and TA EMG activity was significant (r = 0.56-0.98, p<0.05).We conclude that RSNEP corresponds to the activity of the expiratory muscle transversus abdominis, and that this simple maneuver may be useful for assessment of expiratory muscle strength.This study was approved by Kitasato university human ethics committee. This work was supported by MEXT of Japan KAKENHI (2350061). ER -