Mediastinum Flashcards
The mediastinum is divided by an imaginary plane that runs from…
the sternal angle to the T4 vertebrae
Superior mediastinum is bounded…
anteriorly by the manubrium and posteriorly by vertebral bodies of T1-T4
Inferior mediastinum is bounded…
anteriorly by the body of the sternum and posteriorly by the vertebral bodies of the lower 8 thoracic vertebrae
The inferior mediastinum is divided into the…
anterior mediastinum
middle mediastinum
posterior mediastinum
anterior mediastinum is the space between
the pericardium and the sternum
middle mediastinum includes the…
pericardium and the heart
posterior mediastinum is the space between
pericardium and the vertebral column
the superior mediastinum contains
neural structures
vascular structures
respiratory structures
they pass from the adjacent region of the neck and abdomen via the inferior mediastinum
in children the superior mediastinum also contains
the thymus
The thymus contributes to the…
development and maintenance of the immune system
The thymus is most prominent in
childhood
the thymus involutes after puberty and is replaced by
fatty tissue
the thymus is located in the…
lower part of the neck and anterior part of the superior mediastinum
blood supply for the thymus
internal thoracic arteries
veinous drainage for the thymus
internal thoracic veins
brachiocephalic veins (innominate veins)
the thymus lies posterior to the _______ and in children can extend into the ___________
manubrium
anterior mediastinum to lie anterior to the pericardium
where would a tumor in the anterior mediastinum most likely be
the thymus
The great systemic blood vessels of the heart lie within the…
superior mediastinum
the main branches of the great blood vessels arise before passing through
the superior thoracic aperture
what are the 3 great vessels
Arch of the Aorta
Pulmonary Trunk
Superior Vena Cava
What tributaries of the superior vena cava are located within the superior mediastinum
Brachiocephalic Veins
left superior intercostal vein
Supreme intercostal vein
Azygos vein
Brachiocephalic veins drain blood from…
the upper body
left superior intercostal vein collects blood from…
the left 2nd and 3rd intercostal vein
drains into the left brachiocephalic vein
supreme intercostal vein drains…
the vein from the 1st intercostal space directly into brachiocephalic veins
Azygos vein receives blood from the…
right posterior intercostal veins
Superior Vena Cava returns blood from all structures…
superior to the diaphragm EXCEPT for the lungs and heart
Intercostal veins drain into the
azygous vein system
The hemiazygous vein and the accessory hemiazygous vein drain
drain across the verterbal column over to the azygous
the accessory hemiazygous and the hemiaxygous vein collect blood from
the left intercostal veins
brachiocephalic artery is only on
the right side
The hemiazygos vein runs
superiorly in the lower thoracic region to the left side of the vertebral column
Accessory hemiazygos vein is formed by
the union of the 4th to 7th posterior intercostal veins
esophageal cancer can quickly spread to the lung by
draining into the azygos vein
azygos vein -> superior vena cava -> right atrium -> right ventricle -> get pumped out by the pulmonary artery into the lung
The pulmonary trunk bifurcates into the
left and right pulmonary arteries
pulmonary trunk exits from the
right ventricle
the pulmonary trunk is situated…
initially anterior to the aorta it moves medially and posteriorly
The right pulmonary artery passes posterior to the
ascending aorta
the 3 major branches of the aortic arch arise with the…
superior mediastinum
the aorta begins with the…
ascending aorta at the aortic orifice of the left ventricle
what are the 3 major branches of the aortic arch?
Brachiocephalic artery
Left common carotid
Left subclavian artery
Brachiocephalic artery supplies
right side of the head and neck
right upper limb
left common carotid artery supplies
left side of the head and neck
Left subclavian artery supplies
left upper limb
vessel components of the superior mediastinum
left common carotid artery
left and right recurrent laryngeal nerve
left internal jugular vein
left subclavian vein
left subclavian artery
anterior scalene
right phrenic nerve
Brachiocephalic trunk
what are the 4 types of aneurysms of the aorta
ascending aorta aneurysm
aortic arch aneurysm
descending aorta aneurysm
abdominal aorta aneurysm
what aortic aneurysms are an issue in terms of nerve compression
ascending aorta aneurysm
aortic arch aneurysm
descending aorta aneurysm
what are the branches of the vagus nerve?
Right vagus nerve
Left vagus nerve
right recurrent laryngeal nerve
left recurrent laryngeal nerve
the vagus nerve has 2 distinct paths (name them)
right vagus nerve
left vagus nerve
the right vagus nerve runs…
parallel to the trachea and passes posteriorly to the superior vena cava and right primary bronchus
the left vagus nerve enters the…
superior mediastinum between the left common carotid and the left subclavian arteries
descends anteriorly to the aortic arch before traveling posterior to the left bronchus
If there is a tumor in the anterior mediastinum, where is it most likely to be?
the thymus
the right recurrent laryngeal hooks around the…
right subclavian artery and ascends between the trachea and esophagus to supple the larynx
the left recurrent laryngeal nerve arises from the…
left vagus nerve as it passes the aortic arch it loops under the arch to the left of the ligamentum arteriosum before going to the tracheal esophageal groove in the larynx
vagus nerve travels through the neck with the…
internal jugular veins and the common carotid arteries
the right and left vagus nerves give off…
parasympathetic branches that contribute to the cardiac and pulmonary plexuses
When the vagus nerves pass behind the main bronchi they converge to form what?
esophageal plexus
Superior to the diaphragm the plexus gives rise to
two vagal trunks
posterior and anterior
the right recurrent laryngeal nerve does NOT
enter the mediastinum
The right recurrent laryngeal nerve is spatially related to the
apex of the right lung
the right recurrent laryngeal nerve hooks around the
right subclavian artery
the left recurrent laryngeal nerve hooks around the
aortic arch
the left recurrent laryngeal nerve is spatially related to the lymph nodes of the
aortic arch
injury to the recurrent laryngeal nerves can result in
unproductive cough
weakened voice
loss of voice
can cause problems in the respiratory tract
what is the ligamentum arteriosum
fibrous remnant of the ductus arteriosus extending between the aortic arch and the pulmonary trunk
what is the ductus arteriosus?
a fetal blood vessel that connects the left pulmonary artery to the descending aorta
in utero the ductus arteriosus serves as a
bypass for the lungs
Nerves in the superior mediastinum include
phrenic nerve
Cardiac nerves
the phrenic nerve sits on what muscle
anterior scalene muscle
the phrenic nerves enter the
superior mediastinum lateral to the great vessels and descend anteriorly into the middle mediastinum passing anteriorly to the hilum of the lung
(if you can make this card better pls do info on slide 25)
(i have no idea what is happening)
the phrenic nerve supplies motor innervation to the?
diaphragm
the phrenic nerve supplies sensory innervation to the
mediastinal pleura
diaphragmatic pleura
Cardiac nerves originate from the
superior middle and inferior cardiac ganglia
cardiac nerves form the superficial and deep
cardiac plexuses
the cardiac plexuses are located in the
superior mediastinum
the superficial plexus sits between the
aortic arch and right pulmonary vein
the deep plexus lies on the surface of the
trachea at the point of bifurcation
sympathetic trunk runs…
bilaterally to the vertebral bodies along the entire length of the vertebral column
the trachea is what to the esophagus
anterior
the posterior surface of the trachea is…
flat
the trachea ends at the…
sternal angle
the posterior mediastinum includes
thoracic aorta
esophagus
thoracic duct
the thoracic aorta beings at the…
inferior border of t4
the thoracic aorta descends on the
left side of T5-T12 vertebrae
the thoracic aorta becomes the ______ once it passes through the aortic hiatus
abdominal aorta
the thoracic aorta supplies
intercostal spaces and thoracic viscera
esophagus is what to the arch of the aorta
posterior
what is the thoracic duct
the largest lymphatic channel in the body
where does the thoracic duct orginate
cisterna chyli and ascends through the posterior and superior mediastina
what does the thoracic duct drain into
the union of the left internal jugular vein and the subclavian vein
the thoracic duct drains lymph from the whole body EXCEPT
the right side of the head and neck
right side of the thorax
upper surface of the liver
the right jugular, subclavian, and bronchomediastinal trunks enter the veins on the right side of the neck as the…
right lymphatic duct
The superficial tissues drain lymph into the
axillary and internal thoracic nodes
the deep tissues drain lymph into the
internal thoracic node
intercostal node
diaphragmatic node
(then subsequently into the thoracic duct)
the heart drains lymph into
lymphatic vessels that follow the coronary arteries
ultimately draining to the inferior tracheobronchial nodes
home is where the heart is?!?!?
FALSE.
the middle mediastinum is where the heart is
(hehe you’re welcome for the comedic relief)
