Gross Anatomy of Lungs

Question 1

Size, Shape & Appearance

Answer 1

Conical Shape: apex, base, lateral face, medial hilum.
Runs from thoracic inlet to diaphragm.
Right lung: 3 lobes; Left lung: 2 lobes
Left ling 10% smaller - cardiac notch
~6L in total between the two lungs.

Question 2

Location

Answer 2

Thoracic cavity

Paired organs, separated from each other by the heart and other structures in the mediastinum.

Question 3

Size, Shape & Appearance cont..

Answer 3

Lobes - each lung divides by 1 or 2 fissures.
Terminal bronchioles are smallest part of conducting zone.
Branch into respiratory bronchioles which divide into alveolar ducts.
About 25 orders of branching. Over 2000km of airway!

Question 4

Size, Shape & Appearance … Pleural membrane

Answer 4

Each lung enclosed by double-layered pleural membrane - Parietal pleura, lines wall of thoracic cavity. Visceral pleura, covers lungs themselves.
Pleural cavity is space between layers - pleural fluid reduces friction, produces surface tension.

Question 5

Relations

Answer 5

Inferior: Diaphragm
Anterior: Costal cartilages, ribs
Posterior: Costal cartilages, ribs
Superior: Thoracic inlet
Medial: Thoracic vertebrae, mediastinum bronchi, major vessels, oesophagus

Question 6

Blood Supply & Drainage

Answer 6

Dual blood supply.
Pulmonary circulation: oxygenation of deoxy blood for systemic circulation. R and L pulmonary arteries and right and left pulmonary veins which drain into the RA.

Question 7

Lymphatics

Answer 7

Superficial network drains visceral pleura.
Deep network drains the bronchi.
Both networks drain to bronchopulmonary nodes then to thracheobronchial nodes.