Pleural Cavities Flashcards
Describe the Trachea
- C-shaped hyaline cartilaginous rings
- Bifurcates into right & left main bronchus at TIV/TV
- Carina – hook-shaped tracheal ring
- Trachealis muscle
What are the differences between the right and left main bronchi of the bronchial tree?
R: =Wider =Vertical =Shorter =Divides into 3 L: =Long =More horizontal =Thin =Divides into 2
What is the order of the bronchial tree?
- Trachea
- Main bronchus (primary)
- Lobar bronchi (3R, 2L) (secondary)
- Segmental bronchi (tertiary)
- Conducting bronchioles
- Respiratory bronchioles
- Alveoli
- Alveolar ducts
- Alveolar sacs
Describe alveoli
-Microscopic air cells
-Gas exchange
-150-300 million in adult lungs
-Single layer of epithelial cells & elastic fibres line the walls of each alveolus
=Allow them to stretch/ contract during breathing
-Surrounded by a network of capillaries for gas exchange
-Coated in a thin film of pulmonary surfactant
=Prevents alveoli from collapsing
Describe the lungs
- Organs of gaseous exchange
- Elastic connective tissue
- Small airways, blood vessels, nerves & lymphatic tissue
What are the external features of the lungs?
Right: -Superior, Middle and Inferior lobes -Oblique fissure -Horizontal fissure Left: -Superior and Inferior lobes -Oblique fissure -lingula
What are the external borders of the lung?
Right: -Anterior border -Costal surface -Inferior border -Mediastinal surface -Apex Left: -Apex -Mediastinal surface -Posterior border -Base (diaphragmatic surface)
Describe the right medial surface if the lungs
-Hilum =Where important structures enter/ exit each lung -Root structures =Pulmonary arteries =Pulmonary veins =Bronchus -Impressions =Superior vena cava =Inferior vena cava =Oesophagus =Azygos vein
Describe the left medial surface of the lungs
-Smaller than right lung-
-Hilum
=Where important structures enter/ exit each lung
-Root structures
=Pulmonary arteries
=Pulmonary veins
=Bronchus
-Impressions
=Heart
=Aortic arch
=Thoracic aorta
=Oesophagus
=Left subclavian artery
Describe the hilum
=Root =Hilum =Pulmonary ligament -Main structures entering the hilum =Primary bronchi =Pulmonary arteries (deoxygenated blood) -Main structures exiting the hilum =Pulmonary veins (oxygenated blood) -Other structures: =Bronchial arteries & veins =Lymph vessels =Efferent & afferent autonomic nerves
Describe the blood supply to the lungs
- Left and Right pulmonary artery
- Lobar and segmental arteries and veins
- Left pulmonary veins
What is the pleura of the lungs?
=Two pleural cavities (R & L)
=Lining membrane
=Pleural sac
-Parietal pleura =Costal =Mediastinal =Diaphragmatic =Cervical
-Visceral pleura
=Adheres to walls of lung
=Covering surface of each lobe
During development the lung is pushed into the sac to form the two layers
What is the role of the pleura in collapse of lungs?
- Separated by mediastinum
- Rupture of a lung allows entry of air into pleural cavity
- Surface tension adhering visceral to parietal pleura breaks = lung collapses
- Wont affect other lung
Describe the surface anatomy of the lungs
- Lungs don’t completely fill the pleural cavity
- Potential spaces
- Expansion of lungs into these spaces occurs during forced inspiration
- Midclavicular and midaxillary lines
- Turns laterally at 6th costal cartilage
- Crosses midaxillary line at Rib X
- Crosses midclavicular line at Rib V111
What is the Costo- diaphragmatic recess?
- Between costal pleura and diaphragmatic pleura
- Clinically important