Posterior mediastinum Flashcards
What are the following boundaries of the posterior mediastinum?
- anterior
- posterior
- superior
- inferior
anterior = heart and pericardium
posterior = T5-T12
superiorly = angle of louis
inferiorly = diaphragm
What are the contents of the posterior mediastinum
DATES
Descending thoracic aorta
Azygous vein
Thoracic duct
Esophagus
Sympathetic trunk chain
What are the two branches of the descending thoracic aorta
parietal and visceral branches
What is included in the parietal branches of the descending thoracic aorta
posterior intercostal arteries
subcostal artery
superior phrenic arteries
What is included in the visceral branches of the descending thoracic aorta
pericardial, bronchial, esophageal and mediastinal branches
What is the function of the azygous vein
drains blood from the body wall and moves it to the superior vena cava
What is the difference between the accessory azygous and hemiazygous vein
both drain blood but hemiazygous only drains blood up to T9 and accessory only drains blood up to T8
Describe the function of the thoracic duct
begins at the cisterna chyli and drains the abdominal viscera, pelvis and lower limbs. Runs from LII to the root of the neck and lymph is drained into the venous system and is emptied into the junction of the left subclavian and left internal jugular vein
What arteries supply the oesophagus
oeseophageal arteries from the aorta
bronchial arteries
ascending branches of the gastric arteries
What veins are associated with the oesophagus
small vessels returning to the azygous vein, hemiazygous vein and oesophageal branches to the left gastric veins
What do the right and left vagus nerves go on to form
forms the oesophageal plexus. then goes on to form:
- anterior vagal trunk (mainly from fibres from the left vagus nerve)
- posterior vagal trunk (mainly from fibres from the right vagus nerve)
What is the sympathetic trunk
2 parallel chains, each with 11/12 ganglia
State the differences between the first 5 ganglion of the sympathetic trunk and the posterior 7
first 5 = postganglionic sympathetic fibres, supply the thoracic viscera
posterior 7 = preganglionic sympathetic fibres, supply abdominal and pelvic nerves. also contains the splanchnic nerves
What are the 3 types of splanchnic nerves
greater, lesser and least
Where is the greater splanchnic nerve and what is its role
from T5 -> T 9/10
ends in the celiac ganglion
provides sympathetic innervation to the abdominal viscera
What are the 3 hiatus’
caval, oesophageal and thoracic aorta
What is the caval hiatus and what T level
T8
- IVC
- terminal branches of right phrenic nerve
What is the oesophageal hiatus and what T level
T10
oesophagus
right and left vagus nerves
oesophageal branches of left gastric arteries/veins
What is the thoracic aorta and what T level
T12
aorta
thoracic duct
azygous vein
What is the thoracic aorta hiatus also known as
the median arcuate ligament -> a type of crus where the diaphragm thickens around the hiatus
What occurs when the phrenic nerve stops working
paralysis of the diaphragm
What type of muscle is the diaphragm
skeletal because you can control your breathing
What stage of respiration needs energy
inspiration because the diaphragm is actively pushed down
How can you differentiate between a CT above and below the sternal angle
above = trachea has not bifurcated
How can you identify the pulomonary trunk in a CT
Y shaped
What is the structure of the right hilum of the lung
bronchus superior
pulmonary vein inferior
pumonary artery in the middle
What is the blood supply to the SA node
nodal arery from RCA
What is the blood supply to the AV node
nodal artery from RCA
What is the blood supply to the AV bundle of his
mainly yhe LAD artery
Where do the ostia of the coronary arteries lie
the openings for the R+L coronary arteries lie just above the aortic valve
What is an angioplasty
using a balloon to stretch open a narrowed artery
What is a stent
metal tube used to keep vessels open
Describe the vessels between the right brachial artery and the right coronary artery
right brachial artery
right axillary artery
brachiocephalic trunk
arch of aorta
ascending aorta
right aortic sinus
right coronary sinus
right coronary artery
