Preliminary examinations with an innovative device for physiotherapy, VRP 1-Desitin ("Flutter"), in patients suffering from chronic mucus retention and bronchial collapse gave encouraging results. Therefore, we tried to confirm these findings and to evaluate the use of this new physiotherapy. It is based on oscillations of air in the respiratory tract during expiration (rate about 2 to 32 Hertz) diminishing adhesiveness of bronchial mucus and bronchial collapse. Pressure and flow changing depend on the position of mouth-piece and effort of breathing. In order to establish the efficiency of the VRP 1 a comparing investigation was initiated. 20 patients with cystic fibrosis, aged 7 to 28 years, performed physiotherapy with VRP 1 and autogenic drainage (AD), respectively, in a randomized order one after another, each physiotherapy taking twenty minutes. The expectorated sputum was weighed by means of a precision balance. Mean values during VRP 1 treatment were 5.0 g (range 0 to 12.0 g), during AD 4.8 g (range 0 to 11.7 g). There was no statistical difference (p < 0.05). The results were not influenced by the order of physiotherapy.CONCLUSIONSVRP 1 physiotherapy is as effective as AD with respect to sputum elimination. In opposite to other methods not requiring a helping person it is simple to teach and to learn. It may be performed by young children (> or = 3 years) and adults, also in combination with inhalation. Thus, VRP 1 appears to be a real enrichment in physiotherapy.