Lecture 8 RH Flashcards
What is the mediastinum?
Mediastinum is an area in the thoracic cage in the center of the thoracic cavity. It contains the space between the lungs.
What are the sections of the mediastinum? What separates them?
superior mediastinum
inferior mediastinum
They are separated by the plane of louis. (At the manubriosternal joint)
What happens at the plane of louis and what are some structures present nearby?
between T4 and T5
It is the point where the great vessels leave the heart.
It is the point where the Main bronchi bifurcate.
What are the postero anterior sections of the mediastinum?
heart is at the middle mediastinum.
Anteriorly is the thoracic cage and the pericardium.
Posteriorly is the descending aorta and all the structures behind the heart directly.
Where is the thymus located?
immediately deep to the manubrium is the thymus..
what is the function of the thymus?
Thymus is important for the development of the immune system. It is lost during puberty due to redundancy.
What are the branches of the superior vena cava?
Superior vena cava forms 2 branches; the right and left brachiocephalic veins.
What are the branches of the left and right brachiocephalic veins?
right brachiocephalic vein forms the right subclavian and right internal jugular vein.
Left does the same with left subclavian and internal jugular.
What are the branches of the aortic arch?
Brachiocephalic artery to the right.
Left common carotid
Left subclavian artery
What does the aorta arch over?
Posteriorly to the left over the left pulmonary trunk and the left main bronchus before descending into the posterior inferior mediastinum.
What is the purpose of the brachiocephalic trunk?
forms a bridge between the aortic arch and the right subclavian + right common carotid.
What are the first branches of the aorta?
The coronary arteries.
What are the main nerves that innervate the heart?
Right and left vagus nerves
Right and left phrenic nerves
Right and left recurring laryngeal nerves. (these nerves come of the vagus nerves and curl under the left side of the aortic arch and goes back up to the larynx)
What is the purpose of the recurrant laryngeal nerves?
For phonation
What structure is the left recurrant laryngeal nerve really close to?
The ligamentum artereosum.
What is the clinical significance of the location of the left recurrant (recurrent you daft cunt) laryngeal nerve?
Cardiosurgeons repairing a patent ductus artereosus could potentially accidentally constrict the nerve causing phonation problems.
What are the structures found in the superior mediastinum?
oesophagus
trachea
Thoracic duct (drains lymph from below diaphragm into the left brachiocephalic vein)