function
Last reviewed 01/2018
The functions of the trachea are:
- maintenance of airway patency:
- against positive pressure from within the thoracic cavity by the discontinous ring of cartilage
- against shearing of the trachea by longitudinal forces as the elasticity of the tube permits stretching; essential when:
- swallowing - the larynx moves superiorly relative to the tracheal bifurcation
- inspiring - the diaphragm and hence the central mediastinal contents including the tracheal bifurcation move inferiorly relative to the larynx
- protection:
- mucus from the goblet cells and submucosal glands traps particles
- 'mucociliary escalator' of co-ordinated ciliary movement moves mucus to the larynx for swallowing
- mucus humidifies the passing air to minimize dessication of mucosa
- mucus warms the air
- site of receptors for sensory nerves which run in vagus; involved with afferent limb of protective cough reflex
- special reflexes e.g. trachealis contraction during cough decreases luminal calibre and elevates intratracheal pressure prior to release of vocal cords