Objective: To determine whether a mucus clearance device (MCD) (Flutter; Axcan Scandipharm, USA) could consistently improve the bronchodilator response and exercise performance in patients with chronic obstructive pulmonary disease (COPD) when used in an ambulatory setting over a one-week period.
Subjects: Fifteen patients with severe COPD (mean age 71+/-10 years) were studied.
Methods: A randomized crossover design compared an MCD with a sham MCD (SMCD), in which each were tested for one week. At the beginning and end of each study week, forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were measured before and after MCD or SMCD. A bronchodilator aerosol (ipratropium bromide and salbutamol sulphate) was then given, and FEV1 and FVC were remeasured 30 min, 60 min and 120 min later. A 6 min walk test (6MWT) was also performed.
Results: FEV1 improved significantly (P<0.05) after bronchodilator administration with both the SMCD and MCD. The improvement was always greater with MCD use than with SMCD. At the baseline measure, 120 min postbronchodilator administration, the mean FEV1 improved by 24+/-24% with SMCD use and 60+/-28% with MCD use (P<0.05). After one week of use, the corresponding values at 120 min were 19+/-24% and 43+/-26% (P<0.05). Similar findings were obtained for FVC. 6MWT distances increased by 29+/-12 m (P<0.05) after one week of MCD use, whereas it decreased slightly (by 16+/-18 m) after SMCD. The decline in saturation with the 6MWT was smaller with MCD use than with SMCD use. After one week, the decline in saturation with MCD use was similar to baseline levels, although patients were walking farther. After one week, dyspnea was lower on walking with MCD use than with SMCD use.
Conclusion: Patients with COPD had an increased response to bronchodilator therapy after use of the MCD compared with SMCD use. The increase persisted after one week of use, and was associated with improved exercise performance as measured by the 6MWT.