Airway clearance in COPD: need for a breath of fresh air? A systematic review.

BACKGROUND: Airway clearance is a key component of respiratory physiotherapy management for patients with excess secretions, including patients with chronic obstructive pulmonary disease (COPD). The aim of this review is to give an overview of the available evidence for the use of different airway clearance techniques (ACT) and their effects in patients with COPD.
METHODS: A systematic literature search was performed on CEBAM, PUBMED, Cochrane CT, Science Direct and Biomed central data bases. After screening, a total of 26 articles were included.
RESULTS: Studies that provide solid evidence of the effectiveness of different airway clearance techniques in patients with COPD are rather scarce. The available evidence indicates that active breathing techniques, such as active cycle of breathing techniques, autogenic drainage and forced expiration, can be effective in the treatment of COPD. The evidence for passive techniques such as postural drainage and percussion is low. Supporting techniques such as intrapulmonary percussive ventilation, positive expiratory pressure and non-invasive ventilation have little evidence because of the small number of studies. Little evidence is found for the combined use of active techniques and supporting techniques such as (oscillating) positive expiratory pressure, postural drainage and vibration in COPD patients. There is clearly a need for well-powered controlled clinical trials on the long-term effects of (combined) airway clearance techniques in COPD.