The Mediastinum Flashcards
What area does the Mediastinum cover?
Extends from:
- Thoracic inlet/aperture
- Diaphragm
- Sternum & costal cartilages
- Thoracic vertebrae
What is the function of the mediastinum?
The mediastinum allows for movement of the lungs, heart and great vessels and protects them
What great vessels are in the superior mediastinum?
- Aorta (arch and descending)
- Left and right common carotid
- left and right subclavian
- Brachiocephalic trunk
What nerves are in the superior mediastinum?
- Phrenic(C3, 4, 5) provides motor to diaphragm and sensory to pericardium mediastinal pleura
- Recurrent Laryngeal loops under arch and right subclavian to innervate larynx
- Vagus (CN X) innervated heart, oesophagus and bronchi
What veins are in the superior mediastinum?
- Superior vena cava
- Brachiocephalic
What other structures are in the superior mediastinum?
- Oesophagus
- Thoracic duct
- Thymus gland
- Lymphatic trunks
What structures are the in inferior mediastinum?
- Heart
- Inferior vena cava
- Oesophagus
- Descending aorta
What structures are in the anterior mediastinum?
Thymus gland
What structures are in the middle mediastinum?
- Heart
- Pericardium
What structures are in the posterior mediastinum?
- Primary Bronchi
- Descending aorta
- Azygos and Hemi Azygos veins
- Thoracic duct
- Oesophagus and oesophageal plexus
What are the results of phrenic nerve paralysis?
Elevation of the ipsilateral hemidiaphragm
What spinal levels does the trachea extend across?
C6-T4
What is the bifurcation of the trachea known as?
Carina - bifurcation into primary bronchi at the transthoracic plane
Where is the oesophagus positioned?
- immediately posterior to the trachea
- inclines to the left but is compressed by the aortic arch and the root of the left lung root
What is the outer layer of the pericardium called and what is it’s function?
Fibrous pericardium
- stabilises the heart and prevents overdilation
