: anterior to the bodies of the inferior 8 thoracic vertebrae (T5-T12), Inferior to the pericardium, and posterior to the pericardium
Esophagus:
collapsed tube slightly to the right
2 vagal nerves:
right vagus is posterior to the root of the right lung; left vagus crosses left side of aortic arch
esophageal plexus:
where the vagal fibers separate and spread out on the esophagus
vagal trunks:
where the bundles of the esophogeal plexus come together
anterior
: bundles from left vagus
posterior
: bundles from right vagus
ligamentum arteriosum:
cord connecting left pulmonary artery to the aortic arch
left recurrent laryngeal nerve:
branch of left vagus, posterior to ligamentum arteriosum
azygos system of veins:
intercostal veins
on right side are tributaries to the azygos vein (runs along right side)
hemiazygos veins
bring blood from the left side
thoracic duct:
thin walled, pale, easily torn structure found between the azygos vein and the descending aorta; it traverses the diaphragm together with the descending aorta
descending aorta
posterior intercostal branches
off of aorta
bronchial arteries
arise from the descending aorta
greater splanchnic nerve
on right and left; receives fibers from the 5th through the 10th thoracic sympathetic ganglia
sypathetic trunks
lie posterior to each lung and not between the mediastinal pleurae; thus not in any divisions of the mediastinum
splanchnic nerves
and a much smaller lesser splanchnic nerve just lateral to the greater splanchnic nerve
Superior Mediastinum
Orientation of the superior mediastinum
: bordered by superior aperture of thorax, thoracic vertebrae 1-4, manubrium of sternum, mediastinal pleurae of the 2 lungs, and by a plane from sternal angle to intervertebral disc T4-T5
Thymus:
fatty mass immediately posterior to the manubrium
Great veins:
2 brachiocephalic veins
(at right margin of manubrium) meet to form the
superior vena cava
(azygos vein drains into it)
Arch of Aorta and branches:
Aortic arch:
begins and ends at the sternal angle anteriorly and intervertebral disc T4-T5 posteriorly
Brachiocephalic trunk:
arises from summit of the aortic arch
Left common carotid artery
Left subclavian artery
(lies posterior to the left common carotid artery)
Aortic arch
becomes descending aorta after it arches over the left main bronchus
Left phrenic nerve:
between the subclavian artery and subclavian vein, and crosses over aortic arch
Left vagus:
between the left common carotid and subclavian arteries, crosses left side of aortic arch
Left recurrent laryngeal nerve
: immediately posterior to the ligamentum arteriosum
Right phrenic nerve:
descends lateral to the superior vena cava, anterior to root of Right lung, lateral to pericardial sac, and lateral to the inferior vena cava
Right vagus:
travels along the rights side of the trachea
Deep cardiac plexus:
between aortic arch and the bifurcation of the trachea
Trachea and related structures:
Tracheobronchial lymph nodes:
on both sides of the trachea and in the vicinity of its bifurcation; fills the angle within the fork of the trachea and intervenes between the right pulmonary artery and esophagus