Embryology - The Lungs and Pleural Cavities Flashcards
What fills the pleural cavity?
Serous fluid
Pleural cavities are larger than the lungs at rest, creating…
pleural recesses
Serous fluid is produced by …
the serous membranes of the pleura
What is the function of serous fluid? (2)
- Lubricate the pleural space so the lungs can move smoothly during respiration
- Maintain negative pleural pressure
Where is the visceral and parietal plera continuous?
At the hilum of the lung.
Key features of the parietal pleura (2)
- much thicker than the visceral pleura
- divided into 4 parts
Name the 4 parts of the parietal pleura
- cervical part
- costal part
- diaphragmatic part
- mediastinal part
What is a pleural reflection?
Lines along which the parietal pleura changes direction
What are pleural recesses?
Spaces into which our lungs can expand
Costomediastinal recess
(where, which is larger and why)
Spaces posterior to the sternum; left recess larger due to cardiac notch
Costodiaphragmatic recess
(which area is larger)
Inferior gutter-shaped spaces that follow the diaphragm where it meets the ribs. Larger posteriorly than anteriorly.
Pneumothorax
Air in the pleural cavity. Pressure will become higher than the pressure of the lung, so it will be difficult for the lung to expand and it may even collapse.
What is the treatment for a pneumothorax?
Needle decompression (needle is inserted through the 2nd intercostal space at the midclavicular line)
A tension pneumothorax is associated with a
a) contralateral mediastinal shift
b) ipsilateral mediastinal shift
a contralateral mediastinal shift (mediastinum moves AWAY from the affected side)
A non-tension pneumothorax or atelectasis is associated with a
a) contralateral mediastinal shift
b) ipsilateral mediastinal shift
b) ipsilateral mediastinal shift (the lung has collapsed, so the mediastinum moves TOWARDS the affected area)
What is atelectasis?
Partial or total collapse of the lung
Define the following:
a) simple pneumothorax
b) tension pneumothorax
c) closed pneumothorax
d) open pneumpthorax
a) simple: non-expanding (no mediastinal shift)
b) tension: expanding pressure (mediastinal shift)
c) closed: air enters from within the respiratory tract
d) open: air enters from outside the body