Cough is an important mechanism of airway clearance. In
patients who present weak and ineffective cough, augmentation
techniques aim to assist or simulate the maneuver. These
techniques target different phases of the cough cycle, mainly the
inspiratory and expiratory phases, through assisted inspiration,
assisted expiration and their combination. They include the
manual hyperinflation, ventilator hyperinflation, glossopharyngeal
breathing, manually assisted cough and mechanical insufflatorexsufflator, each applied individually or in different combinations.
The aim of this review is to investigate the effectiveness and
safety of cough augmentation techniques. Findings support that
all commonly used techniques can theoretically improve airway
clearance, as they generate higher cough peak flows compared
to unassisted cough. Still, the studies assessing cough
augmentation present considerable limitations and the direct
comparison of different techniques is challenging. Current
evidence indicate that cough peak flow shows higher increase
with the combination of assisted inspiration and expiration, and
improvement is greater in patients with lower unassisted values.
Associated adverse events are infrequent.