High-frequency chest wall oscillation

During high-frequency chest wall oscillation (HFCWO), positive pressure air pulses are applied to the chest wall. Oscillation and vibration can be applied externally to the chest wall or abdomen by rapidly oscillating pressure changes in a vest (ThAIRapy Vest , American Biosystems, Inc., St. Paul, Minnesota, U.S.A.), or by cycling oscillating pressures... 

Figure 13 High-frequency chest wall oscillation through a chest shell (Hayek oscillator, Breasy Medical Equipment Inc., Stamford, Connecticut, U.S.A.).

Chaisson KM, Walsh S, Simmons Z, et al. A clinical pilot study high frequency chest wall oscillation airway clearance in patients with amyotrophic lateral sclerosis. Amyotroph Lateral Scler 2006 7(2) 107-111. 

Darbee JC, Kanga JF, Ohtake PJ. Physiologic evidence for high-frequency chest wall oscillation and positive expiratory pressure breathing in hospitalized subjects with cystic fibrosis. Phys Ther 2005 85(12) 1278-1289. 

Scherer TA, Barandun J, Martinez E, et al. Effect of high-frequency oral airway and chest wall oscillation and conventional chest physical therapy on expectoration in patients with stable cystic fibrosis. Chest 1998 113(4) 1019-1027. 

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