Lecture 3: Lungs, Pleura & Bronchial Tree Flashcards
Where does the trachea start?
Lower border of cricoid cartilage
What are the features of the cartilaginous rings in the trachea?
U-shaped, deficient posteriorly
What makes up for the deficiency in the cartilaginous rings of the trachea?
Trachealis
Where does the trachea bifurcate and what are the divisions?
T4/5
Left and Right main bronchi
What are the features of the right main bronchus?
Shorter, wider, more vertical, divides before the hilum of the lung into superior and intermediate (divides into middle and inferior in the lung)
What are the features of the left main bronchus?
Divides into superior and inferior branches once past the hilum of the lung
How many orders of branching are there in the lower airways?
25
When does cartilage stop in the airways and what are the consequences of this?
Transition from bronchi to bronchioles - airways are now collapsable
How many bronchopulmonary segments are there per lung and what are their features?
10, pyramidal shaped, apex directed towards hilum, functionally distinct tissues
What is asthma?
Spasm of smooth muscle around the lower airways - bronchioles with no cartilage collapse - reduced air supply
What are the features of the right lung?
3 lobes (superior, middle, inferior) and 2 fissures (oblique, horizontal)
What are the features of the left lung?
Pushed over due to heart position, 2 lobes (superior, inferior), 1 fissure (oblique)
What are the positions of pulmonary arteries and veins?
Arteries are superior and posterior, veins and inferior and anterior
Can you tell the difference between the major arteries and veins surrounding the heart?
Not really - don’t have major pressure differences so haven’t adapted characteristic features
What do the bronchial arteries supply?
Connective tissue in and around airways
What is parenchyma?
Non-resp parts of lungs
What is the venous drainage of the parenchyma?
Bronchial veins - azygous
What is present in the hilum of the lung?
Artery, vein, lobar bronchi (2 right, 1 left), lymph nodes, bronchial arteries
Where do the vagus and phrenic nerves run in relation to the lung hilum?
Vagus nerve running posterior to the hilum and phrenic anterior
What is the sympathetic nerve supply for the lungs?
Sympathetic chain T1-4
What is the parasympathetic nerve supply for the lungs?
Vagus
What lymph node drains the lungs?
Deep pulmonary lymph nodes - hilar nodes - bronchomediastinal trunks - thoracic or right ducts
What are the black deposits in the lungs?
Carbon and aggregation of macrophages
What is the pleura and what is it divided into?
Closed double layered membrane - parietal and visceral
What is the pulmonary ligament?
Where the parietal pleura reflects over vessels at hilum and becomes visceral pleura
What is the sensory supply to the parietal pleura?
Intercostal and phrenic nerves
What is the sensory supply to the visceral pleura?
Sympathetics of organ
What happens if the surface tension in the lung is broken?
Lung recoils - pneumothorax or hemothorax
