Influence of the Vibralung Acoustical Percussor on pulmonary function and sputum expectoration in individuals with cystic fibrosis

Background: The Vibralung Acoustical Percussor is a new airway clearance therapy (ACT) utilizing intrapulmonary sound waves in addition to positive expiratory pressure (PEP). We evaluated the safety of the Vibralung and collected preliminary data on its ability to mediate sputum expectoration in individuals with cystic fibrosis (CF). Methods: Over two separate studies, 10 and 11 mild to moderate CF patients were recruited for study I and II, respectively. Study I: Vibralung was used for 20 min with either no sound (NS: PEP only) or sound (S: PEP and sound) on randomized visits. Pulmonary function, diffusion capacity of the lungs for carbon monoxide and nitric oxide (DL_CO/DL_NO), symptoms, and peripheral oxygen saturation (SpO₂) were measured at baseline and at 1 and 4 h post treatment. Expectorated sputum was collected over 4 h post treatment. Study II: over 5 days of in-hospital therapy, the Vibralung or vibratory vest therapy (Vest) were used for two therapy sessions per day, with sputum collected for 20 min following each therapy and pulmonary function accessed pre and post each 5-day period (days 1–5 or 7–11) in a randomized crossover design. Results: Vibralung usage resulted in no change from baseline to 4 h post in pulmonary function, SpO₂ or symptoms (p > 0.05). At 4 h post therapy, the DL_CO- and DL_NO-derived measure of alveolar–capillary unit function (DM/V_C) showed improvement (DM/V_C = 12.5 ± 5.5 versus 7.3 ± 18.8% change, S versus NS) with no difference between S and NS (p = 0.74). Sputum expectoration was similar between S and NS conditions (wet sputum = 10.5 ± 4.6 versus 9.9 ± 3.2 g, S versus NS, p = 0.25). There were no differences in the improvement in pulmonary function between Vibralung and Vest during either 5-day period during the hospital stay. Conclusions: Vibralung was well tolerated and caused no detrimental changes in pulmonary function metrics. The Vibralung appears to be a safe ACT in individuals with CF.