Lungs

Question 1

Blood supply of lungs

Answer 1

Pulmonary trunk -> pulmonary arteries (right and left) -> superior and inferior pulmonary arteries (right and left)
Intercostobronchial trunk and thoracic aorta -> bronchial arteries (right and left)
The bronchial veins provide venous drainage. The right bronchial vein drains into the azygos vein, whilst the left drains into the accessory hemiazygos vein.

Question 2

Nerve supply of lungs

Answer 2

The nerves of the lungs are derived from the pulmonary plexuses. They feature sympathetic, parasympathetic and visceral afferent fibres:
* Parasympathetic – derived from the vagus nerve. They stimulate secretion from the bronchial glands, contraction of the bronchial smooth muscle, and vasodilation of the pulmonary vessels.
* Sympathetic – derived from the sympathetic trunks. They stimulate relaxation of the bronchial smooth muscle, and vasoconstriction of the pulmonary vessels.

Question 3

Lymph drainage of lungs

Answer 3

Question 4

what covers the lungs?

Answer 4

visceral pleura

Question 5

Parietal pleura covers…

Answer 5

Covers internal surface of the thoracic cavity-
* Mediastinal pleura – Covers the lateral aspect of the mediastinum (the central component of the thoracic cavity, containing a number of organ).
* Cervical pleura – Lines the extension of the pleural cavity into the neck.
* Costal pleura – Covers the inner aspect of the ribs, costal cartilages, and intercostal muscles.
* Diaphragmatic pleura – Covers the thoracic (superior) surface of the diaphragm.

Question 6

Pleural cavity is…

Answer 6

The pleural cavity is a potential space between the parietal and visceral pleura. It contains a small volume of serous fluid, which has two major functions.
It lubricates the surfaces of the pleurae, allowing them to slide over each other. The serous fluid also produces a surface tension, pulling the parietal and visceral pleura together. This ensures that when the thorax expands, the lung also expands, filling with air.
* Costodiaphragmatic – located between the costal pleurae and the diaphragmatic pleura.
* Costomediastinal – located between the costal pleurae and the mediastinal pleurae, behind the sternum.

Question 7

Respiratory system structure and function divisions

Answer 7

Question 8

Trachea origin and bifurcation level

Answer 8

• Starts at C6
• C- shaped cartilage rings in walls to maintain airway
• Open part of C faces posteriorly.
• Posterior wall is mainly smooth muscle
• Bifurcates at T4/5 into L&R Bronchi

Question 9

Bronchial tree divisions

Answer 9

• Primary bronchus enters the lung root via the hilum (door).
• Within the lung, the primary bronchi divides into lobar bronchi (secondary)
• Lobar bronchi divide into segmental bronchi (tertiary)- supply bronchopulmonary segments

Question 10

Distal conducting portion of bronchial tree divisions

Answer 10

Question 11

Bronchopulmonary segment is supplied by its own…

Answer 11

Portion of lung that is supplied by its own segmental arterial branch

Question 12

What are the lobes of the lungs?

Answer 12

Question 13

Lung impressions and hilium

Answer 13

2 bronchial arteries to left
1 bronchial artery to right

Question 14

Lung surface anatomy

Answer 14

Question 15

What is pleura and what are the layers?

Answer 15

A double layered, thin, mesothelial membrane which surrounds and adheres to the lungs.
• Visceral layer: adheres to lungs
• Parietal layer: adheres to chest wall
• Pleural cavity: A potential space between the two pleural layers. Contains pleural fluid

Question 16

Clinical relevance of pleura

Answer 16