Physiological effects of Simeox Airway Clearance Device in healthy adults

Abstract

Introduction: Airway clearance devices (ACDs) assist in mobilizing retained secretions in lung diseases by increasing the velocity of expiratory flow. Aim: Aim of this study was to characterize oscillatory flow and negative expiratory pressure pulses generated by a new ACD in healthy subjects. Methods: 10 healthy adults activated a device (Simeox, PhysioAssist) generating intermittent pulses of intrapulmonary negative air pressure during relaxed exhalations. The procedure was repeated twice with 4 settings (25% or 100% power at 6 or 12 Hz frequency). Oscillatory flow and pressure pulses were measured at the mouth with a flow sensor (TSI, Certifier FA plus) to assess Maximal expiratory flow (MEF), maximal mid-expiratory flow (MMEF), Mean expiratory flow (EFmean), maximal expiratory flow amplitude (MEFamp), peak of negative expiratory pressure (NEPpeak) and maximal expiratory pressure amplitude (MEPamp). Results: 60% male, 34±12y, FEV1/FVC 90±14%. Data are presented in table 1. MEF (60 to 120 l/min) and MEFamp (70 to140 l/min) rates supported generation of high airflow velocity during exhalation over power range. Oscillatory flow was maintained at mid-exhalation. Low variability of data showed high reproducibility of flow and negative pressure pulses generated with Simeox during procedure. Range of pressure was safe (-10 to -60 mbar). Conclusions: These data suggest that Simeox may be an efficient and secure technology for airway clearance therapy.