Viscera (heart, lungs, liver, gastrointestinal tract)
Trachea
Trachea
- Origin
- Originates at the lower border of the cricoid cartilage (C6 level) and descends through the superior mediastinum
- Insertion
- Bifurcates at the carina (sternal angle, T4-T5 level) into the left and right main bronchi
- Function
- Conducts air between the larynx and bronchial tree while warming, humidifying, and clearing debris via the mucociliary escalator
- Innervation
- Vagus nerve (CN X, recurrent laryngeal nerves) and sympathetic trunk
- Movement & chain
- Dynamic mobility during respiration (descends 2-3 cm during deep inspiration) and coughing (trachealis muscle contraction narrowing diameter to accelerate airflow)
- Palpation
- Palpable in the suprasternal notch; assessed for midline positioning vs. tracheal shift
- Clinical
- Tracheal deviation is a critical physical sign of tension pneumothorax (away from affected side) or massive atelectasis (toward affected side). Tracheal stenosis, tracheostomy.
- Segmental innervation
- C6-T5 levels
- In clinical practice
- Endotracheal tube cuff pressure monitoring (20-30 cmH2O to prevent mucosal ischemia), sterile suctioning technique, emergency surgical airway management
- Region in the model
- Viscera (heart, lungs, liver, gastrointestinal tract)