The effect of positive expiratory pressure versus forced expiration technique on tracheobronchial clearance in...

In a randomized cross-over trial, including a control measurement the effect of positive expiratory pressure (PEP) and forced expiration technique (FET) on tracheobronchial clearance was evaluated in eight chronic bronchitics with abundant sputum production (mean, 32 g/day). PEP consisted of PEP-mask breathing interspersed with breathing exercises, huffing, and coughing. FET consisted of postural drainage, breathing exercises, huffing, and coughing. Clearance was measured with a radio-aerosol technique. At 40 min after the start of therapy the mean clearance, expressed as percentage of the amount of radioactivity present at the start of therapy, was 32% after PEP, 53% after FET, and 15% in the control run. The difference between PEP, FET, and control was statistically significant (p less than 0.02). Sputum production during PEP and FET was larger than during the equivalent period of time in the control run. It is concluded that FET is more effective than PEP in enhancing tracheobronchial clearance.