The Science Journal of the American Association for Respiratory Care
BACKGROUND: High frequency ventilation has been used in devices to create intrapulmonary percussive effects and promote airway clearance. Two percussive devices were evaluated, and the flow and volume waveform characteristics were compared for high frequency oscillation. The parameters important for intrapulmonary percussive type ventilation are: f - oscillation frequency (Hz), proximal PIP - Peak Inspiratory Pressure (cm-H2O), OTV - Oscillatory Tidal Volumes (ml), and MV - Minute Volume (Liters) during inhalation and exhalation.
Methods: Each device was connected to a pressure tap and a flow sensor proximal to the mouthpiece to record pressure and flow waveforms using a computer data acquisition system sampling pressure at 100 Hz. Model IPV
Results: The results of this evaluation are summarized below with flow waveforms.
|Device||f (Hz)||PIP (cm-H2O)||OTVINHL (ml)||OTVEXHL (ml)||MVEXHL (L)|
|IPV ||5||27.6 ± 4.2||85.6 ± 3.8||221.3 ± 4.2||66|
|IPV ||7||23.2 ± 0.5||28.2 ± 0.6||148.7 ± 2.9||62|
|PT-HF @ 35 PSIG||11||21.6 ± 0.5||22.2 ± 1.7||61.8 ± 2.1||40|
DISCUSSION: The results indicate that oscillation frequencies vary slightly depending on the setting of the devices. The oscillation frequency f for the IPV
Conclusions: The flow waveform of the PT-HF is compatible to that of the IPV
Supported by VORTRAN Medical Technology 1, Inc.
(See Original for Figure)