Resp 3 - Anatomy 3

Question 1

Name the intercostal muscles from superficial to deep:

Answer 1

External
Internal
Innermost

Question 2

In what direction do the fibres of the External Intercostal muscles run? What is their role?

Answer 2

Down and anteriorly

Pull ribs up and out = 30% chest expansion during quiet respiration

Question 3

In which direction do the fibres of the Internal and Innermost Intercostal muscles run? What is their role?

Answer 3

Down and posteriorly

Pull ribs down during forced expiration

Question 4

What do the intercostal nerves supply?

Answer 4

• Intercostal muscles
• Parietal pleura
• Overlying skin

Question 5

Define the origins of the diaphragm:

Answer 5

• Xiphoid process
• Interior 7-12 costal cartilages
• Arcuate ligament
• Crura of diaghragm

Question 6

What is the insertion of the diaphragm?

Answer 6

Central tendon of the diaphragm

Question 7

Which 2 muscles are responsible for chest expansion in quiet respiration?

Answer 7

1) External Intercostal muscles ~ 30%

2) Diaphragm ~ 70%

Question 8

Which nerve supplies the diaphragm? What are its roots?

Answer 8

Phrenic nerve

C3, C4, C5 keeps the diaphragm alive

Question 9

How many openings does the diaphragm have, what structures pass through them?

Answer 9

3:
@ T8 = Inferior Vena Cava
@ T10 = Oesophagus
@ T12 = Abdominal Aorta

Question 10

At which spinal level does the Aorta pass through the diaphragm?

Answer 10

T12

Question 11

At which spinal level does the IVC pass through the diaphragm?

Answer 11

T8

Question 12

At which spinal level does the oesophagus pass through the diaphragm?

Answer 12

T10

Question 13

In what order do the intercostal nerves, arteries and veins run along the ribs from superior to inferior?

Answer 13

Vein, Artery, Nerve (VAN)

Question 14

Where should a needle be inserted for pleural aspiration/chest drain, and why?

Answer 14

Upper border of rib, to avoid intercostal neurovascular supply

Question 15

Which arteries supply the parietal pleura?

Answer 15

Intercostal arteries

Question 16

Where do the Intercostal arteries arise from?

Answer 16

Anterior segment = Internal Thoracic artery

Posterior segment = Superior Intercostal artery

Question 17

Where do the intercostal veins drain into?

Answer 17

Anterior segment = Internal Thoracic vein

Posterior segment: RHS = Azygos, LHS = Hemiazygous

Question 18

How much pleural fluid is usually present?

Answer 18

~ 10-20 ml

Question 19

Name the 3 reflections of the pleura:

Answer 19

Anterior = Sternal
Posterior = Vertebral
Inferior = Costal

Question 20

What is responsible for producing and absorbing pleural fluid?

Answer 20

Capillaries of parietal surface = Produce pleural fluid

Parietal lymph nodes = Absorb pleural fluid

Question 21

What are the main functions of the pleural fluid?

Answer 21

• Reduce friction

- Create surface tension = cohesion (when chest expands, so does lungs)

Question 22

What is the blood supply to and from the visceral pleura?

Answer 22

Bronchial arteries

Bronchial veins

Question 23

What is the main difference between the nerve supply to the parietal and visceral pleura?

Answer 23

Parietal = Somatic and Autonomic
Visceral = Autonomic only (no pain)

Question 24

What is the Carina?

Answer 24

Ridge at the base of the trachea which separates the L and R bronchi

Question 25

What is the name of the ridge separating the entrances to the R and L bronchi?

Answer 25

Carina

Question 26

How many lobar bronchi are there in each lung?

Answer 26

Right lung = 3 | Left lung = 2

Question 27

What is the name of the airway supplying each bronchpulmoanry segment?

Answer 27

Segmental bronchi

Question 28

What is a bronchopulmonary segment?

Answer 28

Pyramidal area of lung, each supplied by a segmental bronchus, artery and vein. (Branches of pulmonary and bronchial)

Question 29

How are bronchopulmonary segments useful in surgery?

Answer 29

Can be isolated and removed with minimal bleeding, air leakage or interference with other segments

Question 30

Where do the Bronchial arteries arise from?

Answer 30

``` Right = 3rd Intercostal artery Left = Aorta ```

Question 31

How is the blood supply to the lungs maintained after a pulmonary embolus?

Answer 31

Anastamoses are present between the pulmonary and bronchial arteries (dual blood supply)

Question 32

Which veins drain most of the blood supplied by the Bronchial arteries?

Answer 32

Pulmonary veins

Question 33

Name the parasympathetic nerve which has afferent and efferent fibres in the lungs:

Answer 33

Vagus nerve

Question 34

Name the 2 lymphatic plexuses in the lungs, and the lymph node they drain to:

Answer 34

1) Superficial sub-pleural lymphatic plexus (deep to visceral pleura) 2) Deep bronchopulmonary lymphatic plexus (in submucosa of bronchi and peribronchial tissue) Hilar lymph nodes

Question 35

Define the mediastinum:

Answer 35

Central compartment of thoracic cavity, between the 2 pleural sacs

Question 36

Name the 4 divisions of the mediastinum:

Answer 36

1) Superior 2) Anterior 3) Middle 4) Posterior

Question 37

Name the borders of the superior mediastinum:

Answer 37

``` Superior = Thoracic inlet Inferior = Sternal angle line Anterior = Manubrium Lateral = Pleural sacs Posterior Vertebral bodies T1-4 ```

Question 38

Name the contents of the superior mediastinum:

Answer 38

- Great vessels - Nerves (Vagus, Phrenic, Cardiac and sympathetic trunk) - Oesophagus - Trachea - Thymus - Thoracic duct

Question 39

Name the borders of the anterior mediastinum:

Answer 39

``` Superior = Sternal angle line Inferior = Diaphragm Anterior = Body of sternum and Transverse Thoracis muscles Lateral = Mediastinal pleura (part of parietal pleura) Posterior = Pericardium ```

Question 40

Name the contents of the anterior mediastinum:

Answer 40

Nothing | Except Thymus in childhood - receeds in adulthood

Question 41

Name the borders of the middle mediastinum:

Answer 41

``` Superior = Sternal angle line Inferior = Diaphragm Anterior = Anterior margin of Pericardium Lateral = Mediastinal pleura Posterior = Posterior margin of Pericardium ```

Question 42

Name the contents of the Middle Mediastinum:

Answer 42

- Heart + Pericardium - Tracheal bifurcation + L/R bronchi - Great vessels - Nerves (cardiac plexus + phrenic) - Tracheobronchial lymph nodes

Question 43

Name the borders of the Posterior Mediastinum:

Answer 43

``` Superior = Sternal angle line Inferior = Diaphragm Anterior = Posterior margin of the Pericardium Lateral = Mediastinal pleura Posterior = Vertebral bodies T5-12 ```

Question 44

Name the contents of the Posterior Mediastinum:

Answer 44

- Thoracic Aorta - Thoracic duct - Oesophagus - Azygos vein system - Sympathetic trunk