Mediastinum

Question 1

Name a few things found in the superior mediastinum.

Answer 1

Thymus gland
Superior Vena Cava
Arch of aorta
Vagus and phrenic nerves
Trachea and esophagus
Thoracic duct

Question 2

Where is the thymus gland located?

Answer 2

Posterior to the manubrium but anterior to the brachiocephalic vein

Question 3

When is the thymus gland active?

Answer 3

During childhood prior to puberty

Functionally inactive in adults- atrophy results

Question 4

Which brachiocephalic vein crosses the trachea anteriorly?

Answer 4

The left brachiocephalic vein

Question 5

At what level does the aortic arch begin and end?

Answer 5

T4-T5 (sternal angle)

Question 6

What does the aortic arch arch over?

Answer 6

It arches over the Left main bronchus and pulmonary trunk

Question 7

What are the three arteries that arise from the aortic arch?

Answer 7

Brachiocephalic trunk
Left common carotid
Left subclavian artery

Question 8

T/F the vagus nerve descends posterior to the root of the lung?

Answer 8

True

Question 9

The vagus supplies what kind of innervation to the thorax?

Answer 9

Parasympathetic

Question 10

The phrenic nerve descends _____ to the root of the lung.

Answer 10

Anterior

Question 11

The phrenic nerve supplies _____ innervation to the diaphragm.

Answer 11

Somatic

Question 12

The phrenic nerve comes from which spinal levels?

Answer 12

C3-5

Question 13

Where is the trachea in relation to the esophagus?

Answer 13

It is immediately anterior to i

Question 14

Where does the trachea bifurcate?

Answer 14

At the inferior limit of the superior mediastinum

Question 15

T/F numerous lymph nodes are found at the carina?

Answer 15

True

Question 16

What is the carina?

Answer 16

It is the ridge that denotes the bifurcation of the trachea into right and left main bronchi

Question 17

Foreign bodies are usually aspirated into which main bronchus? Why?

Answer 17

The right one

It’s more vertically oriented and is shorter and WIDER than the left main bronchus

Question 18

Where is the carina usually positioned in regards to the median plane?

Answer 18

Just to the left of it

Question 19

The esophagus descends _____ to the trachea

Answer 19

immediately posterior

Question 20

Where does the esophagus pierce the diaphragm?

Answer 20

At the esophageal hiatus

Question 21

The esophagus empties into where?

Answer 21

the stomach

Question 22

T/F the stomach may herniate through the esophageal hiatus?

Answer 22

Truth

Question 23

What is a type I sliding hiatal hernia?

Answer 23

It is where the stomach slides freely into the thorax- this is the most common and is often asymptomatic

Question 24

What is a type II paraesophageal hernia?

Answer 24

It is where the fundus has basically escaped through the esophageal hiatus and is stuck up next to the esophagus- can risk gastric blood supply

Question 25

What is found in the posterior mediastinum?

Answer 25

``` Esophagus and esophageal plexus Azygos system veins Descending aorta Thoracic duct Thoracic splanchnic nerves ```

Question 26

The esophageal plexus is made from what?

Answer 26

The joining of the vagus nerves.

Question 27

The left vagus nerve forms the ____ vagal trunk and the right vagus nerve forms the _____ vagal trunk.

Answer 27

Anterior | Posterior

Question 28

The azygos system of veins provides venous drainage for what?

Answer 28

The thorax

Question 29

The azygos vein drains what?

Answer 29

intercostal veins from the right side of the thorax

Question 30

The hemiazygos and accessory hemiazygos veins drain what?

Answer 30

The left thorax

Question 31

What do the the hemiazygos and accessory hemiazygos veins drain into?

Answer 31

The azygos vein

Question 32

The azygos vein arches over what to drain into what?

Answer 32

arches over the Right superior bronchus to drain into the superior vena cava

Question 33

In relation to the esophagus, where does the descending aorta lie?

Answer 33

just left of the esophagus

Question 34

What does the aorta supply and give rise to (via branches)?

Answer 34

gives rise to the posterior intercostal arteries supplying the thorax and supplies branches to the trachea, bronchi, and esophagus

Question 35

Where does the thoracic duct lie?

Answer 35

It lies posterior to the esophagus and anterior to the vertebral bodies

Question 36

The thoracic duct is located between the _____ vein and the _____ _____.

Answer 36

azygoes vein | descending aorta

Question 37

The thoracic duct drains lymph from where?

Answer 37

The entire body below the diaphragm

Question 38

Where does the thoracic duct enter the venous angle?

Answer 38

Between the left sublcavian vein and the left IJV

Question 39

What is a chylothorax?

Answer 39

The accumulation of lymph in the pleural cavity

Question 40

How does one go about getting a chylothorax?

Answer 40

Tear your thoracic duct- often from a trauma during surgery or a lymphoma

Question 41

is chylothorax visible on chest films?

Answer 41

yes

Question 42

What are the two types of branches from the sympathetic chain ganglia?

Answer 42

1st branch- postganglionic sympathetics to thoracic viscera | 2nd branch- preganglionic sympathetic to the abdomen, not the thorax

Question 43

What are the three nerves that come off the 2nd branch type of the chain ganglia?

Answer 43

greater, lesser, and least splanchnic nerves

Question 44

For thoracic autonomics, from which spinal levels do sympathetics originate from?

Answer 44

T1-T5

Question 45

For thoracic autonomics, from where do parasympathetics originate from?

Answer 45

CN X

Question 46

The sympathetics and parasympathetics intermingle to form 3 thoracic plexuses- what are they?

Answer 46

Cardiac Pulmonary Esophageal