Mediastinum

Question 1

what structures enclose the mediastinum (sup, inf, ant, post)

Answer 1

sup- superior throacic apeture
Inf- diaphram
Ant- sternum and costal cartilages of true ribs
post- T1-12 vert bodies

Question 2

What is the transverse thoracic plane and what does it divide + level

Answer 2

Divides mediastinum to sup and inf parts.

Goes thru sternal angle and IVD T4/5/bifurcation of trachea

Question 3

where is the thymus located (+ in children)

Answer 3

Located just post to mandibrium in adults (in child it will get into the inf mediastinum)

Question 4

Blood supply and venous drainage of thymus

Answer 4

Blood- int thoracic artery + 1st and 2nd intercostal aa

Venous- int thoracic vein + brachiocephalic trunks

Question 5

Lymph drainage of thymus

Answer 5

Drains into parasternal tracheobronchial lymph nodes

Question 6

where does the thoracic duct drain into

Answer 6

Left venous angle (int jug and subclavian meet)

Question 7

What drains into the right venous angle (and what doesi it drain)

Answer 7

R lymphatic duct

-lymph produced by r head, neck, upper limb and thorax

Question 8

Superior vena cava- location in relation to trachea/aorta, what nerve runs over it and what major vein drains into its post

Answer 8

anteriolat to trachea, right of ascending aorta (attaches to r mediastinal pleura

• R phrenic runs over it
• Azygos vein drains into its post

Question 9

If a thymus tumor develops what could it compress and what s the symptoms

Answer 9

Can compress L brachciocephalic vein and cause edema in left upper limb

Question 10

What is the ascending aorta part of and located in

Answer 10

in pericardial sac and belongs to the middle mediastinum

Question 11

where does the arch of the aorta start and end

Answer 11

begins at 2nd chondral jt arches up towards left and sup to root of right lung and ends at ivd T4/5

Question 12

Branches of arch of aorta (starting from closest to heart) + what % of ppl have this pattern

Answer 12

60% have this pattern

1. Brachiocephalic trunk (divides into right subclav + R comon corotid)
2. Left comon corotid
3. Left subclavian

Question 13

What is the ligamentum arteriosum and what did it connect and what nerve passes under

Answer 13

rementent of ductus arteriosus- connection bw left pulmonary artery to aortic arch

-left recurent pharyngeal passes under

Question 14

what are the two parts of the trachea

Answer 14

cervical

thoracic- superior thoracic apeture down to where R + L main bronchi bifurcate

Question 15

What does the R main bronchus pass infront of

What does L main bronchus pass infront and behind to

Answer 15

R- ant to axygos v (shorter and wider)

L- Ant to esophagus, inf to arch of aorta

Question 16

If you inhaled an object where would it likely get stuck

Answer 16

sucked into r main bronchus and lodge in one of the lobar branches

Question 17

Thoracic part of esophagus is ant and post to what

Answer 17

ant- to VB t1-4

post to trachea

Question 18

a trachea tumor or aortic anerysium can compress this structure

Answer 18

upper part of esophagus causing swallowing issues

Question 19

What are the 3 divs of the inf mediastinum

Answer 19

Ant, middle and post mediastinum

Question 20

Where is the ant mediastinum located and contents

Answer 20

Bw sternum and pericardial sac

• Sternopericardial ligs, fat, retrostenal lyph nodes, int thoracic vessels, inf thymus (in children)

Question 21

Where is the medial mediastunum located and contents (4)

Answer 21

located bw the ant and post walls of the pericardial sac

pericardial sac with heart inside, ascending aorta, pulmonary trunk, intrapericardial portion of SVC and IVC

Question 22

where is the post mediastinum located (what is ant + post) and contents (4)

Answer 22

located bw post pericardial sac and VB T5-12

thoracic aorta, thoracic duct, azygos vein, lower part of esophagus + nerve plexus

Question 23

Where does the thoracic aorta travel and what are the branches (6)

Answer 23

downward on left side of T5-12 (then becomes abdominal aorta)

Branches- Esophageal, pericardial, mediastinal (off front), bronchial, paired intercostal, sup phrenic

Question 24

where does the thoracic duct originate and travel to

Answer 24

originates at level of L1/2, ascends with aorta on post side bw azygos vein and drains into l venous angle

Question 25

what is the lower part of the esophagus located bw

Answer 25

bw the pericardial sac ant and post t5-10 VB

Question 26

Where is the azygos vein located and what makes it up and drains into it

Answer 26

On right side of vert bodies.
formed by union of R ascending lumbar v and r subcostal v

also collects post intercostal veins on R except 1st

Question 27

What does the hemi azygos vein collect and drain into

Answer 27

union of left ascending lumbar w left subcostal + lower 3 left post intercostal v

then crosses and drains into azygos

Question 28

what does the accessorzy hemi azygos drain

Answer 28

left 4 middle intercostal veins into azygos

Question 29

Path of R phrenic n and inn

Answer 29

-descends ant to scalene and decendis on r braichicephalic and sup vena cava and r pericardial sac

Inn- supplies mediastinal and diaphragmic pleua, pericardial sac, r diaphram and cystic nerve plexus (gallbladder)

Question 30

Inflammation of gall bladder will refer to what dermatomes

Answer 30

R c4,5 dermatomes

Question 31

Right vagus nerve path and end targets

Answer 31

enters ant to subclavian artery, gives off branch to reccurent laryngeal nerve here that ascends back up to inn larynx.
Will continue to descend post to root of lung and divides into many branches to go to pulmonary n plexus, to cardiac n plexus and esophageal n plexus. At exit point of mediastinum most of the fibres of r vagys nerve turns to post vagal trunk which exits thru esophageal hiatus

Question 32

Sympathetic trunk- Branches

Answer 32

T1-5- cardiopulmonary splanchnic
t5-9- Esophageal, greater splanchnic and cilia ganglia
T10-11- lesser splanchnic
t12- lesser splanchnic

Question 33

path of left phrenic n and inn

Answer 33

left side of aortic arch and root of lung + pericardial sac and ends when entering diaphram

inn- Supplies mediastinal pleura, diaphramatic pleura, pericaldial sac, diaphram (L)

Question 34

Left vagus n path and branches

Answer 34

enters bw l common carotid and subclavian. Passes over l aortic arch and gives off to l larengeal reccurent n (ascends to supply l vocal mm and l larynx). After it passes past to root of left lung it gives off branches to pulmonary and cardiac and esophageal nerve plexus. At exit point it will be called ant vagal trunk

Question 35

what is coarctation of aorta

Answer 35

narrowing of arch of aorta before or after the insertion of ligamentum arteriosum
-causes low BP in lower limbs

Question 36

What is double arch of aorta and what can it cause

Answer 36

Arch will split and two and wrap esophagus and trachea

-breathing/swallowing complaints