Comparing performance of three oscillating positive expiratory pressure devices at similar amplitude and frequencies of oscillations on displacement of mucus inside trachea during cough.

Background: Performance of Flutter® (Axcan Scandipharm Inc, Birmingham, AL), Acapella® (Smiths Medicals Inc, Rockland, MA) and Quake® (Thayer Medical, Tucson, AZ) were compared at similar frequencies and amplitudes of oscillations at nine angles of the device in clearing simulated mucus inside a tracheal model (trachea) oriented at three angles with or without simulated constrictions in airway upstream of trachea.

Methods: Displacement of 0.4mL of simulated mucus prepared with viscoelastic properties similar to healthy individuals (syrup-like) or patients with COPD (gel-like) using locust bean gum(LBG) solution (0.

Interactions of airflow oscillation, tracheal inclination, and mucus elasticity significantly improve simulated cough clearance.

Background: Viscoelastic properties of simulated mucus, angle of tracheal inclination (theta), and high-frequency airflow oscillations on median displacement of simulated mucus during simulated cough were investigated in this study.

Methods: Mucus simulants with viscoelastic properties similar to healthy individuals and patients with COPD were prepared using locust bean gum (LBG)-water solution (0.38 g LBG in 100 mL water) cross-linked with 3-mL and 12-mL borax-water solution (0.