Airway Clearance

• What are the Necessary Components for an Effective Cough?

  • Ability to increase tidal volume via:
  • inspiratory muscle strength
  • lung compliance
  • chest wall compliance
  • Bulbar muscle function via:
  • allows rapid closure and opening of vocal cords
  • Ability to increase expiratory flow via:
  • expiratory muscle strength
• Why Might These Patients Have A Weak Cough?

  • Inspiratory muscle weakness - cant take deep breath in
  • Expiratory muscle weakness - cant force air out fast
  • Possible reduced chest wall compliance (chronic neurological conditions e.g. DMD)
  • Possible bulbar muscle dysfunction
• What Physiotherapy Techniques Could We Use To Augment Tidal Volume?

  • Active Cycle of Breathing Techniques (LTEEs)
  • Intermittent Positive Pressure Breathing (IPPB)
  • The Bird
  • Inspiratory Positive Pressure increases VT
  • Could also use NIV
  • Combine the above with MTs to increase expiratory flow
• Manually Assisted Coughs:

  • The application of a compressive force
  • Replaces the work of the expiratory muscles
  • Increases expiratory flow
  • Should direct the force down and in (or up and in for Heimlich)
  • Timing is crucial
  • The sound of the resultant cough is a good indicator of whether you have applied enough force
• Types of Manually Assisted Cough:

  • Supine: Costophrenic angles of ribs
  • Supine: Anterior chest compression
  • Supine: Heimlich type assist - pressure on abdomen
  • Sitting: Self assisted (SCIs) - used by patients with spinal cord injury
• Mechanical Insufflation-Exsufflation (Cough Assist):

  • Machine that provides alternating positive and negative pressure
  • Positive pressure will increase tidal volume
  • Negative pressure will increase expiratory flow to simulate a cough
  • Use in conjunction with manually assisted cough
  • Can be applied via an oral-nasal interface or an endotracheal or tracheostomy tube
  • Entrain O2 after turned power on