The short-term effects of chest physiotherapy on lung function tests in children with cystic fibrosis.

Chest physiotherapy is an important part of the treatment program of children 
with cystic fibrosis, but controlled studies of its effects are few. 
27 children with cystic fibrosis, 20 being chronic sputum producers and 
7 non-sputum producers, were studied in hospital with serial lung function 
tests on 3 consecutive days. On the 1st day physiotherapy was 
performed twice; on the 2nd day no physiotherapy was performed; on 
the 3rd day the two periods of physiotherapy were preceded by 
an inhaled bronchodilator (Rimiterol). Lung function tests included peak flow, forced 
vital capacity (FVC), forced expiratory volume in 1 sec (FEV1.0) and 
residual volume to total lung capacity ratio, and were measured at 
the beginning of each day and at similar intervals throughout the 
3 days. Sputum volume and cough frequency were noted on day 
1 and day 3. Physiotherapy resulted in significant improvement of peak 
flow in the sputum producers. However, the FVC and FEV1.0, while 
improving after physiotherapy, also improved on the control day when no 
physiotherapy was performed. This suggests that physiotherapy may be effective in 
removing sputum from central large airways with resultant improvement in peak 
flow, but has little added effect on the more peripheral airways, 
whose airflow improves through the day with normal activity. No significant 
effect was shown in the non- sputum producers although there was 
a trend towards improvement in peak flow. A bronchodilator before physiotherapy 
may be beneficial in those patients who demonstrate significant reduction in 
airflow obstruction at formal testing of bronchodilator response, but may lessen 
the beneficial effects of physiotherapy in those without a positive response. 
The study illustrates the importance of examining difference methods of chest 
physiotherapy, to find ways of improving sputum clearance. 