Lecture 50 - Lower Respiratory Tract Flashcards
What is the thoracic cavity divided into?
Right pulmonary cavity
Left pulmonary cavity
Mediastinum
What protects the lungs?
Bony cage:
Vertebrae
Ribs
Sternum
Muscles
- diaphragm
- intercostals
What are the independent functional units of the lung?
Why is it important to have these units?
Bronchopulmonary segment
It is important because if one segment is compromised, it can be removed and the rest of the lung can function as normal
Are the two sides of the lung dependent on each other?
No
They are completely separate:
- functionally
- structurally: separated by mediastinum
Which pulmonary cavity is smaller?
Right PC
What covers the lung?
Pleura
Single layer of serous membrane
What does the pleura cover?
- parietal pleural: Wall of the pulmonary cavity
- Visceral pleura: Lung
What separates the visceral and parietal pleura?
Describe the features
Pleural cavity
- Very small potential space
- Filled with serous fluid –> reduces surface tension
How is the parietal pleura subdivided?
Draw this
Mediastinal pleura
Diaphragmatic pleura
Costal pleura
Cervical pleura
Slide 10
How do the bronchi get into the lung rough the pleura?
Through the lung route
What is contained within the right lung root?
Pleural sleeve containing:
- pulmonary arteries
- pulmonary veins (anterior and inferior)
- main bronchi
- lymph node
Describe the pleural sleeve
Made up of pleural membrane Encloses the hilum of the lung Loose Hangs down to form double folded: Pulmonary ligament
What separates the lungs into lobes?
Fissures
Where does the visceral and parietal pleura receive its innervation and blood supply?
Visceral: from lung
- autonomic nerve innervation
Parietal: from intercostal a
- somatic innervation
Describe pain associated with parietal and visceral pleura
Parietal: sharp pain
Visceral pleura: dull pain
Due to the different innervation, there is very different quality of pain
Describe the difference between the right and left bronchi.
If a peanut is swallowed, where does it go?
Right:
- Shorter
- Wider
- More vertical
Small objects will go down the right main bronchus due to this
Where is the trachea?
C6 - T4,5
Describe the tissue structure of the trachea
Tracheal ring : of cartilage
Trachealis Muscle at the posterior end
Right up against the oesophagus
What are the divisions of the bronchi?
Main bronchi: supplies each lung
Lobar bronchi: supplies lobe
Segmental bronchi: supplies bronchopulmonary segment
What type of muscle is the trachealis muscle?
Smooth
Where does the trachea branch?
T4,5
Which lung is larger?
Right lung
- shorter (due to liver inferiorally)
- wider
Due to the heart protruding into the left side
What are the surfaces of the lung?
Costal
Mediastinal
Diaphragmatic
Where is the hilum of the lung?
Mediastinal surface
What are the fissures of the lungs?
Right:
- two fissures
- three lobes
Left:
- one fissure
- two lobes
What are the borders of the lung?
Inferior
Anterior
Posterior
What are the grooves and impressions on the mediastinal surface of the right lung?
Grooves:
• oesophagus
• azygos vein
• SVC
Impressions:
• cardiac impression
What are some unique features of the left lung?
Cardiac notch
Lingula
What are the grooves and impressions on the mediastinal surface of the left lung?
Grooves:
• aorta
Impressions:
• cardiac impression
Does the oesophagus pass anterior or posterior to the lung root?
Anterior
What are the lobes and fissures of the right lobe?
Draw this
Lobes:
• superior
• middle
• inferior
Fissures:
- oblique
- horizontal
Which cardiac impression is bigger?
Bigger on the left lung
Where is the inferior lobe located?
Most of it at the back of the lung
What are the lobes and fissures of the left lobe?
Draw this
Lobes:
- inferior
- superior
Fissures:
- oblique
Describe the blood in he pulmonary artery
Why is this weird?
It is deoxygenated
Normally arteries contain oxygenated blood
What vessels provide blood supply for the lung itself?
Bronchial arteries and veins
Where are the pulmonary veins located in the Hilum?
Why?
Most inferior
Most anterior
Need to be somewhere where they can expand fully to collect as much blood as possible
Describe the structures in the left lung hilum
Pulmonary artery
Pulmonary veins: inferior and anterior
Lymph nodes
Left main bronchus
Where does lymph from the lung drain to?
1a. Superficial lymphatic vessels
1b. Deep lymphatic vessels
- Bronchopulmonary hilar nodes
- Tracheobroncho nodes
- Mediastinal nodes
Are the lobes of the lung completely separated by fissures?
No; they connect up at the hilum
Where is the base of the bronchopulmonary segment?
Where is the apex?
Base: external surface
Apex: facing the segmental bronchus
Where is the base of the bronchopulmonary segment?
Where is the apex?
Base: external surface
Apex: facing the segmental bronchus
Compare the location of the pulmonary artery in the left and right lung hilum
Right lung: anterior and superior ( right main bronchus posterior)
Left lung: superior; left main bronchus underneath
Describe the location of superifical lymphatics in the lung
Just beneath the visceral pleura
Visible externally
Describe the location of deep lymphatic vessels in the lung
Run along the bronchial tree
Not visible externally
