Lab 8 Superior and Posterior Mediastinum Flashcards
What fascia is deep to the costal pleura?
endothoracic fascia
What is found anterior to the root of the lung between the mediastinal pleura and the pericardium?
phrenic nerves and pericardicophrenic vessels
The pericardium is the sac for the heart and has an internal serous portion forming __ layer(s) plus anexternal fibrous portion yielding __ total layers.
2
3
The heart is covered by a ___ layer of ________ (epicardium) and the interior of the pericardiac sac is lined with the __________. These two layers are continuous ___ to the heart at the great vessels.
visceral layer of serous pericardium
parietal layer of serous pericardium
posterior
The external portion of the pericardial sac is the ______.
fibrous pericardium
The oblique pericardial sinus is found between the _____. The transverse pericardial sinus is found between the _____.
oblique- pulmonary veins
transverse- ascending aorta and superior vena cava
What can be used to generally divide the superior/inferior mediastina? (not accurately)
pericardial reflection
How many pulmonary veins form the boundary of the oblique sinus?
4
Boundaries of the superior mediastinum: superior: posterior: anterior: lateral: inferior:
s: superior thoracic aperture
p: bodies of thoracic vertebra 1-4
a: manubrium of sternum
l: mediastinal pleurae with left and right pulmonary cavities
i: plane of the sternal angle (sternomanubrial junction to T4, aka transverse thoracic plane)
What is the fatty mass of tissue that lies immediately posterior to the manubrium of the sternum?
adult version of the thymus
Tracing the superior vena cava superiorly you will find the convergence of the ___ and ____ near the inferior border of the right _____.
left and right brachiocephalic veins
1st costal cartilage
The ____ is found superior to the root of the lung and drains into the posterior surface of the SVC.
arch of the azygos vein
What passes posterior to the brachiocephalic veins and anterior to the root of the lung?
R and L phrenic nerves
What projects posterior to the left, obliquely?
arch of the aorta
What are the 3 arteries that arise from the arch of the aorta? Locations of each?
brachiocephalic trunk- most anterior and right (bifurcates to right common carotid and right subclavian)
left common carotid- intermediate
left subclavian- most posterior and left
What is between the concavity of the arch of the aorta and the left pulmonary artery?
ligamentum arteriosum
What nerve is on the left/anterior side of the arch of the aorta? What is the branch of this nerve that curls along the inferior surface of the arch of the aorta (just left of the ligamentum arteriosum) to ascend into the neck?
left vagus nerve
left recurrent laryngeal nerve
In cases of mediastinal tumors or an aneurysm of the aortic arch, the ______ nerve may be compressed leading to _____.
left recurrent laryngeal nerve
hoarseness (paralysis of the left vocal fold)
Phrenic nerves are more ____ than vagus nerves.
lateral
What nerve can be followed inferiorly, posterior to the root of the left lung toward the esophagus?
left vagus nerve
What loops around the right subclavian artery near the bifurcation of the brachiocephalic trunk?
right recurrent laryngeal nerve
What nerve passes posterior to the roof of the right lung toward the esophagus?
right vagus nerve
What is posterior to the brachiocephalic trunk and the aortic arch?
trachea
The bifurcation of the trachea is found at the plane of the ______ forming the ___ and ____ primary bronchus.
sternal angle
right and left
The azygos and aorta arch over their respective ___.
bronchi
What can be found around the bifurcation of the trachea?
tracheobronchial lymph nodes
Characteristics of the trachea/bronchi?
C-shaped tracheal rings, c is open posteriorly toward the esophagus
right primary bronchus is larger in diameter, shorter, and more vertical than the left
What is the ridge of cartilage on the inside of the bifurcation of the trachea?
carina
Boundaries of the posterior mediastinum: superior: posterior: anterior: lateral: inferior:
s: plane of the sternal angle
p: bodies of the thoracic vertebrae 5-12
a: pericardium
l: mediastinal pleurae with left and right pulmonary cavities
i: diaphragm
What plexus is on surface of the esophagus?
esophageal plexus ;)
The thoracic autonomic plexus is formed by branches of the ___ and _____.
vagus nerves and sympathetic trunk
The right vagus nerve can be traced from the right _______, ___ to the root of the right lung and then to the _____, more ___.
subclavian artery
posterior
esophageal plexus
posteriorly
The left vagus nerve can be traced from the left _____, ___ to the root of the left lung and then to the _____, more _____.
side of the aortic arch
posterior
esophageal plexus
anteriorly
What is a “convergence” of the esophageal plexus along the anterior surface of the esophagus, inferiorly?
anterior vagal trunk
What is found along the posterior surface of the esophagus, inferiorly?
posterior vagal trunk
The left vagus nerve forms more of the ___, thus ___ vagal trunk, the right forms more of the _____, thus the ____ vagal trunk.
anterior plexus, anterior
posterior plexus, posterior
The _____ is often found ____ on the thoracic vertebral bodies and even crossing midline onto the _____.
azygos vein
anterior
left side
The are posterior intercostal vein tributaries along the ____, and hemiazygos vein tributaries along the _____.
right side- intercostal
left side- hemiazygos
What is found between the azygos vein and the thoracic aorta?
thoracic duct
What passes through the diaphragm with the thoracic aorta and terminates at the venous angle? At the convergence of what two things?
thoracic duct
left IJV and left subclavian vein
The accessory hemiazygos and hemiazygos vein drain into the azygos vein near the _____ vertebrae. What do they receive as tributaries?
8th/9th thoracic vertebrae
LEFT posterior intercostal veins
The hemiazygos system of veins passes ___ along the ___ side of the thoracic vertebral bodies.
vertically
left
What are the 3 branch sets of the thoracic aorta?
esophageal arteries
left bronchial arteries
posterior intercostal arteries
Unpaired arteries from the anterior surface of the aorta
esophageal arteries
Unpaired arteries from the anterior surface of the aorta onto the posterior surface of the bronchi
left bronchial arteries
Right set crosses the midline over the anterior surface of the thoracic vertebrae, POSTERIOR to all other structures of the posterior mediastinum. The left arteries have direct access to the intercostal space.
posterior intercostal arteries
The sympathetic trunk is found deep to what two things?
parietal pleura and endothoracic fascia
Superior the sympathetic trunk crosses the heads of ribs ____, inferiorly it lies more ____ on the sides of the thoracic vertebral bodies.
ribs 2-9
anterior
There are sympathetic ganglia at each ____.
thoracic vertebral level
What is found between each intercostal nerve and its corresponding sympathetic ganglion? What is more lateral?
gray ramus and white ramus comminicans
white is more lateral
What are the 3 thoracic splanchic nerves? What is special about each?
greater splanchnic nerve: T5-9, largest, most medial
lesser splanchnic nerve: T10-11, intermediate
least splanchnic nerve: T12, smallest, most lateral
The white/gray rami are ___ to the sympathetic trunk, while the splanchnic nerves form ____ to the sympathetic trunk.
posterolateral
anteromedial
