Airway clearance physiotherapy improves ventilatory dynamics during exercise in patients with cystic fibrosis: a pilot study

Background Airflow limitation and dynamic hyperinflation may limit exercise capacity in patients with cystic fibrosis (CF). The aim was to investigate whether the undertaking of airway clearance physiotherapy (ACT) prior to cardiopulmonary exercise testing (CPET) results in improvements in exercise capacity. Methods A prospective randomised, cross-over pilot study was performed in children aged >9 years. Spirometry, plethysmography and CPET were performed on two separate occasions-one test with ACT prior to CPET and the other without. Results 12 patients with CF were included in the study with a mean (SD) age of 12.83 (1.85) years. No significant difference in peak oxygen uptake (VO2) was found between the tests. However, lower minute ventilation (V-E) and ventilatory equivalents (VEVO2 and VEVCO2) at ventilatory threshold (VT) were noted when ACT was undertaken prior to CPET. The mean(SD) VE (L/min) at VT was 26.67 (5.49) vs 28.92 (6.3) (p=0.05), VEVO2 (L/min) at VT was 24.5 (1.75) vs 26.05 (2.5) (p=0.03) and VEVCO2 (L/min) at VT was 26.58 (2.41) vs 27.98 (2.11) (p=0.03). Conclusions These pilot data suggest that ACT prior to exercise may lead to improved ventilatory dynamics during exercise in individuals with CF.