Lexicon of airway clearance and breathing techniques

Airway clearance techniques
 Active cycle of breathing [10, 11]A cycle of deep breathing exercises interspersed with breathing control, followed by the FET (a combination of 1 or 2 huffs# interspersed with periods of breathing control)
 Autogenic drainage [10, 11]Composed of three phases:
  • 1. unsticking the peripheral mucus by breathing at low lung volumes (below FRC)

  • 2. collecting the mucus in the middle airways by breathing at mid lung volumes close to FRC

  • 3. evacuating the secretions from the central airways by breathing at higher lung volumes

 Positive expiratory pressure therapy [10, 11]Provides a constant pressure to the airways throughout expiration using an expiratory resistance device with a one-way valve
 ELTGOL (total slow expiration with open glottis) [12]The patient lies in a lateral decubitus position and breathes out slowly through an open glottis from FRC to residual volume
 Manually assisted cough [13, 14]Thoracic or abdominal compression added to augment the expiratory effort of a cough
 Mechanical insufflation-exsufflation [13, 14]A device gradually inflates the lungs using positive pressure, immediately follows an abrupt change to negative pressure that produces a rapid exhalation
Breathing strategies
 Incentive spirometry [10]Use of a handheld device that provides patients with visual feedback regarding their performance during deep breathing exercises; it can be provided by flow- or volume-based spirometers
 Deep breathing exercises [10]Full inspiration to TLC, with or without a 2–3 s hold at the end of inspiration, followed by relaxed expiration
Adequate expiratory time is required to allow complete expiration
Compared to a rapid inspiration, a slow inspiration allows a more homogeneous distribution of ventilation
 Positive pressure [10]Applying positive pressure throughout inspiration to the airways and lungs by asking the patients to breathe using a device that attaches to them via a face mask or a mouthpiece

FET: forced expiratory technique; FRC: functional residual capacity; TLC: total lung capacity. #: a huff is described as a deep inspiration followed by a forced expiration with the glottis open.