The benefit of chest physiotherapy in patients with cystic fibrosis has been well documented. However, the benefit of similar rehabilitation in patients with large amounts of sputum who have diagnoses other than cystic fibrosis has not been clearly demonstrated. The aim of this study was to evaluate the acute effectiveness of a device advised for home chest physiotherapy in comparison to postural drainage combined with chest percussion in removing secretions in patients with high sputum production due to diseases other than cystic fibrosis. Fourteen in-patients, known to spontaneously produce more than 25 mL sputum.day-1, underwent two sessions each of two treatment modalities in random order. Treatment A consisted of postural drainage and manual chest percussion. Treatment B included breathing through a commercial device claimed to combine oscillating positive expiratory pressure with oscillations of the airflow. Expiratory flows and oxygen saturation were monitored and recorded throughout the study. The amount of sputum produced in the 30 min preceding, during, and in the 60 min after completing each treatment session was recorded, together with the sensation of "chest unpleasantness due to secretions" as assessed by means of a modified visual analogue scale. The mean time that the patients tolerated treatment was not different for A and B (18.7 +/- 5 and 19.3 +/- 5 min, respectively). Sputum significantly increased during both treatment periods and in the same amount for the two modalities (2.9 +/- 2.9 to 10.9 +/- 7.1 and 2.8 +/- 3.1 to 10.1 +/- 10.8 mL for A and B, respectively). Visual analogue scale score significantly decreased at the end of each treatment.(ABSTRACT TRUNCATED AT 250 WORDS)