Lungs and Pleura 2 Flashcards
What does the left lung have, that the right lung doesn’t?
An aortic impression - a broad, deep groove on the medial aspect above and behind the hilum, receiving the arch of the aorta and thoracic aorta.
A cardiac notch - the lateral deflection of the anterior border.
A lingula - a small, fleshy tongue-shaped structure.
What does the right lung have, that the left lung doesn’t?
A middle lobe.
A transverse fissure.
A superior lobar bronchus.
What is a cardiac impression?
A recess formed on the anteroinferior mediastinal surface of both lungs.
It has greater depth in the left lung.
What makes the upper lobes of the lungs vulnerable?
The lungs extend above the first rib and clavicle.
What is Sibson’s fascia?
The suprapleural membrane.
A fascial membrane that covers the lung apex above the thoracic inlet.
It provides rigidity to the thoracic inlet and prevents distortion from changes in intrapleural pressure during respiration.
When can impressions be seen on the lungs?
Mainly on fixed lungs.
Unfixed lungs are more pyramidal and show less grooving by adjacent structures.
Additional lung fissures are common
What is the lymphatic drainage of the lungs and visceral pleura?
Drains into the bronchopulmonary LNs at the bifurcation of the trachea at the lung hila.
Lymphatics pass at the tracheobronchial LNs at the bifurcation of the trachea, which drain into the thoracic duct and right lymphatic duct.
What are the bronchopulmonary segments?
Each lung segment has its own individual blood and air supply from the branches of the pulmonary artery and the bronchi.
This allows a surgeon to remove a particular segment without adversely affecting neighbouring segments.
Describe the pulmonary circulation of the lungs.
The portion of the circulatory system which carries deoxygenated blood away from the right ventricle of the heart to the lungs via the pulmonary artery, and returns oxygenated blood to the left atrium and ventricle via the pulmonary veins.
Describe the bronchial circulation of the lungs.
The arteries arising from the aorta and the 3rd right posterior intercostal artery supply oxygenated blood and nutrition to the lung tissue and larger airways.
They enter the lungs at the hilum, along with the pulmonary arteries.
How many bronchial arteries supply each lung?
Left - two.
Right - one.
What are the two pleura?
Parietal - adheres to the inner surface of the ribs, sternum, and mediastinum.
Visceral - shiny, lines the fissures of the lungs.
Both layers are continuous with each other around the lung root and are identical histologically.
What are the parts of the parietal pleura?
Mediastinal - lines the structures between the two pleural cavities.
Diaphragmatic - lies on the superior surface of the diaphragm.
Costal - lines the inner surfaces of the ribs and sternum.
Apical - covers the apex of the lungs in the root of the neck (below the suprapleural membrane).
How does pleural fluid cause the lung to collapse?
An increase in pleural fluid, due to inflammation and infection, causes lung collapse.
A similar result occurs if air gains access to the pleural space as a result of a penetrating wound or a fractured rib.
What are the two pleural reflections?
Costodiaphragmatic - the inner surface of the ribs onto the superior surface of the diaphragm.
Costomediastinal - the inner surface of the ribs posteriorly to lie on either side of the pericardium of the heart.
