Gross (04.24) The Superior & Posterior Mediastinum Flashcards
prominent and active in childhood prior to puberty
thymus gland
t cell maturation
what happens to the thymus gland in adults
functionally inactive and atrophies
may appear as fatty mass
where does the aortic arch begin and end?
sternal angle or T4-T5
what three arteries does the aortic arch give off before descending?
- brachiocephalic trunk (gives rise to R common crarotid and R subclavian)
- L common carotid
- L subclavian a
what three arteries does the aortic arch give off before descending?
- brachiocephalic trunk (gives rise to R common crarotid and R subclavian)
- L common carotid
- L subclavian a
vagus nerve gives innervation to where?
parasympathetic innervation to thorax (& abdomen)
the vagus n descends ____ to the lungs while the phrenic n descends ____ to the lungs
- posterior
- anterior
what gives somatic innervation to the diaphragm?
phrenic nerve
immediately anterior to esophagus
trachea
where does the trachea bifurcate?
at inferior limit of superior mediastinum (carina)
what are found at the carina?
numerous lymph nodes
in reference to the carina, foreign bodies usually are aspirated into the ___ ___ ___
right main bronchus
which main bronchi is shorter and wider
Right (it is also more vertically oriented)
immediately posterior to trachea
esophagus
when the stomach herniates through the esophageal hiatus
hiatal (hiatus) hernia
what is a type I hiatal hernia?
- sliding hiatal hernia
- stomach slides freely into thorax
- most common
- asymptomatic
what is a type II hiatal hernia?
- paraesophageal hiatal hernia
- fundus
- often fixed in position risking gastric blood supply
what is a type II hiatal hernia?
- paraesophageal hiatal hernia
- fundus
- often fixed in position risking gastric blood supply
infection commonly spreads from ____ space to ____ space
- retropharyngeal
- danger
which side of the vagus nerve is responsible for the anterior vagal trunk
L vagus nerve
which side of the vagus nerve is responsible for the posterior vagal trunk?
R vagal nerve (due to rotation of gut during development)
both trunks of the vagus nerve pass through the ____ with the ____
- diaphragm
- esophagus
what does the azygos system of veins do?
provides venous drainage for thorax
what does the azygos v drain
drains intercostal vv from R side of thorax
what do the hemiazygos and accessory hemiazygos vv drain?
left side of thorax (both drain into azygos v)
the thoracic duct is located where?
between azygos v and descending aorta (thorax)
where does the thoracic duct drain?
lymph from entire body below diaphragm
accumulation of lymph in the pleural cavity as a result of torn or leaking thoracic duct (usually from lymphoma or trauma during thoracic surgery)
chylothorax
accumulation of lymph in the pleural cavity as a result of torn or leaking thoracic duct (usually from lymphoma or trauma during thoracic surgery)
chylothorax
the thoracic duct originates in the _____
abdomen
the thoracic duct originates in the _____
abdomen
what are the two main types of branches from the sympathetic chain ganglia?
- postganglionic symps (T1-T5)(supply thoracic viscera via the three plexuses)
- preganglionic symp ( innevates abdomen, not thorax)
- –greater splanchnic nn
- –lesser splanchnic nn
- –least splanchnic nn
*all heading to abdominal viscera (go right through ganglia)
symp innervation of the thorax originates from where?
T1-T5
para-symp innervation of the thorax originates from where?
CN X
the symps from T1-T5 and the parasymps from CN X commingle to form what three thoracic plexuses?
- cardiac
- pulmonary
- esophageal
