SDL Worksheet - Lungs & Pleura

Question 1

Define pleura and the pleural cavity

Answer 1

The serous membrane investing the lungs (visceral or pulmonary pleura) and lining the walls of the thoracic cavity (parietal pleura); the two layers enclose a potential space, the pleural cavity.

Question 2

Location of mediastinal pleura?

Answer 2

Covers the lateral aspect of the mediastinum (the central component of the thoracic cavity)

Question 3

Location of cervical pleura?

Answer 3

Lines the extension of the pleural cavity into the neck

Question 4

Location of the costal pleura?

Answer 4

Covers the inner aspect of the ribs, costal cartilages, and intercostal muscles.

Question 5

Location of the diaphragmatic pleura?

Answer 5

Covers the thoracic (superior) surface of the diaphragm

Question 6

What are the recesses in the pleural cavity? Why do these occur?

Answer 6

1. Costodiaphragmatic recess 2. Costomediastinal recess Anteriorly and posteroinferiorly, the pleural cavity is not completely filled by the lungs. This gives rise to recesses – where the opposing surfaces of the parietal pleura touch.

Question 7

Where is the costodiaphragmatic recess?

Answer 7

Located between the costal pleurae and the diaphragmatic pleura

Question 8

Where is the costomediastinal recess?

Answer 8

Located between the costal pleurae and the mediastinal pleurae, behind the sternum.

Question 9

What is the clinical importance of these recesses?

Answer 9

Provide a location where fluid can collect (e.g. pleural effusion)

Question 10

Where does the horizontal fissure of the lung run?

Answer 10

Runs horizontally from the sternum, at the level of the 4th rib, to meet the oblique fissure.

Question 11

What are the 3 lung surfaces?

Answer 11

1. Mediastinal surface 2. Base of lung 3. Costal surface

Question 12

Describe the mediastinal surface of the lung

Answer 12

Faces the lateral aspect of the middle mediastinum. The lung hilum (where structures enter and leave the lung) is located on this surface.

Question 13

Describe the base of the lung

Answer 13

Formed by the diaphragmatic surface. It rests on the dome of the diaphragm, and has a concave shape. This concavity is deeper in the right lung, due to the higher position of the right dome overlying the liver.

Question 14

Describe the costal surface of the lung

Answer 14

The costal surface is smooth and convex. It faces the internal surface of the chest wall. It is related to the costal pleura, which separates it from the ribs and innermost intercostal muscles.

Question 15

Where are the nerves of the lungs derived from? What do they feature?

Answer 15

Derived from the pulmonary plexuses. They feature sympathetic, parasympathetic and visceral afferent fibres

Question 16

Where are the parasympathetic fibres of the nerves of the lungs derived from? What do they stimulate?

Answer 16

Derived from the vagus nerve. They stimulate secretion from the bronchial glands, contraction of the bronchial smooth muscle, and vasodilation of the pulmonary vessels.

Question 17

Where are the sympathetic fibres of the nerves of the lungs derived from? What do they stimulate?

Answer 17

Derived from the sympathetic trunks. They stimulate relaxation of the bronchial smooth muscle, and vasoconstriction of the pulmonary vessels.

Question 18

What is the function of the visceral afferent fibres of the nerves of the lungs?

Answer 18

Conduct pain impulses to the sensory ganglion of the vagus nerve.

Question 19

What does the right bronchial vein drain into?

Answer 19

The azygos vein

Question 20

What does the left bronchial vein drain into?

Answer 20

The accessory hemiazygos vein.

Question 21

Describe X-ray during expiration

Answer 21

• Lungs airless and density increased - Raised diaphragm leads to exaggeration of heart size and obscuration of lung bases

Question 22

What is the pleural sac?

Answer 22

A balloon like structure which encloses the lung. There are two, one on either side of the mediastinum.

Question 23

What is the mediastinum?

Answer 23

A space between the pleural sacs which contains the heart and great vessels (and others)

Question 24

What are the attachments of the visceral pleura?

Answer 24

The surfaces of the lung

Question 25

What is represented by potential space A and C?

Answer 25

A - Pleural cavity C - Costodiaphragmatic recess

Question 26

Point B indicates the boundary between which two subdivisions of the parietal pleura?

Answer 26

Diaphragmatic and costal

Question 27

What is the function significance of the pleural recesses?

Answer 27

Allows the smooth expansion of the lungs during inspiration

Question 28

What would be the consequences of a stab injury to the neck if it hit the apex/pleural cavity?

Answer 28

The lung would collapse as the atmospheric pressure would force air into the thoracic cavity.

Question 29

What is haemothorax?

Answer 29

Blood in pleural cavity

Question 30

What is chylothorax?

Answer 30

An accumulation of lymphatic fluid in the pleural space. Lymph formed in the digestive system is called chyle and accumulates in the pleural space due to either disruption or obstruction of the thoracic duct.

Question 31

What is empyema?

Answer 31

A collection of pus in the pleural cavity. Usually associated with pneumonia but may also develop after thoracic surgery or thoracic trauma.

Question 32

Abnormal substances within the pleural cavity may be removed by means of a chest drain. Where is a non-emergency chest drain usually inserted?

Answer 32

5th intercostal space, mid-axillary line.

Question 33

What is the visceral pleura innervated by?

Answer 33

Autonomic innervation from the pulmonary plexus (vagus nerve and sympathetic fibres). It is insensitive to pain stimuli (sensory receptors only detect stretch)

Question 34

What is the parietal pleura innervated by?

Answer 34

Innervated by the intercostal nerves, with the mediastinal and diaphragmatic pleura also innervated by the phrenic nerve

Question 35

Irritation of the parietal pleura can produce referred pain where?

Answer 35

In the thoracic and abdominal walls (intercostal nerves)

Question 36

Left lung root:

Answer 36

Pulmonary artery above bronchus RALS

Question 37

Right lung root:

Answer 37

2 pulmonary arteries: both anterior to the bronchus (looks like next to) RALS

Question 38

What structures pass through the root of the lung?

Answer 38

Pulmonary arteries, pulmonary veins, bronchi, bronchial arteries, autonomic nerves, lymph nodes and vessels

Question 39

Where do the bronchial arteries arise? What do they supply?

Answer 39

Paired vessels from the aorta They supply the bronchi and lung tissue.

Question 40

Where do lymphatic vessels from the lung substance drain to?

Answer 40

Hilar lymph nodes in the lung root which in turn drain to nodes around the bifurcation of the trachea (tracheo-bronchial nodes)

Question 41

What can enEnlargement of the nodes due to infection or carcinoma lead to?

Answer 41

Obstruction of bronchus

Question 42

What is effect of obstruction of a bronchus on the lung?

Answer 42

Deflation of the lung distal to the blockage

Question 43

Compare the right primary bronchus to the left

Answer 43

The right primary bronchus is wider, shorter and more vertical than the left. This accounts for the greater tendency of foreign bodies (e.g. peanuts, an extracted tooth) and aspirated material (e.g vomit) to enter the right bronchus rather than the left.

Question 44

X-ray of thoracic cavity

Answer 44