Ch.48 Trachea Flashcards
How long is the trachea
70-80cm (28-32inches)
How many cartilage rings in the trachea
48 - 60 incomplete rings
How far does the trachea extend
5th or 6th intercostal space
How does the trachea attach to the larynx
Cricotracheal ligament
What direction does the trachea deflect to in the thoracic inlet
Right by the aortic arch
Cartilage of the rings
Hyaline
What muscle spans the gap between the open dorsal ends of the rings
Smooth trachealis muscle
Tracheal diameter
5.5cm cranially
7x5cm width x height caudally
4 layers of the trachea
- Mucosa
- Submucosa
- Musculo cartilaginous layer
- Adventitia -cervical
- Serosa - thoracic
Describe the adventitia
Connective tissue layer composed of loose areolar tissue that blends with the surrounding anatomical structures and allows movement of the trachea along its length
Describe the musculocartilaginous layer
Cartilage rings the trachealis muscle and the fibroelastic annular ligaments. Together cartilage and muscle for complete semi flexible rings
Neighbouring rings are attached to each other by the annular ligaments
Describe the submucosa
Contains elastic fibers, fat cells and seromucous tubular glands which open into the lumen of the trachea
Describe the lumen
Lined by pseudo stratified columnar ciliated epithelium that contains numerous goblet cells and rests on a basement membrane
What rate is the mucociliary escalator
1.6 +- 0.24cm/min
Where is the trachea located in the neck ie surrounding structures
- Visceral space
- Ventral to longus coli muscles
- Carotid sheaths are dorsolateral to
the trachea - The sternothroideus m is ventral to
trachea for most of its length - Oesophagus starts dorsal to trachea
then left side at C4 - Sternohyoid ventral to it in cervical
portion - Sternocephalic, omrohyoid and
sternothroid at lateral to trachea
near larynx - Paired thyroid glands at 1st ring
