Pneumothorax and pleural effusion Flashcards
what is a pneumothorax?
- air in the pleural space occurring spontaneously or due to trauma
- this is due to a hole in the pleura
- loss of negative interpleural pressure and seal between the parietal and visceral pleura
what is a primary spontaneous pneumothorax?
- rupture of a sub-pleural bleb (small- thin walled air containing spaces)
- can be due to a rupture of a bulla
- occur in tall thin men
what can increase the risk if primary spontaneous pneumothorax
- smoking
what is secondary spontaneous pneumothorax?
- occurs secondary to an underlying lung problem
what is a traumatic pneumothorax
- iatrogenic –> caused by invasive medical procedures (vein cannulation, fine needle aspiration)
- accidental –> direct injury to the thorax (penetration lung injury)
what is a tension pneumothorax?
- causes a mediastinal shift and cardiovascular collapse
- one way valve system where air constantly comes In and doesn’t come out
= impaired gas exchange, venous return and cardiac output
why is there reduced venous output to the heart during a tension pneumothorax?
- increased intrathoracic pressure
- but veins rely on a low intrathoracic pressure
-decreased venous blood to heart
-course of veins is also shifted and distorted
why can you see tachycardia in a pneumothorax
the heart rate increases to make up for the decreased pre load (stretching of the heart is reduced due to the pressure around it)
what is needle thoracocentesis?
- procedure that decompresses a pneumothorax
- place code bore cannula into the second intercostal space midclavicular line above third rib
clinical features of a pneumothorax
- sudden onset and dysponea
- chest movement reduced
- percussion is hyper resonant
- breath sounds reduced
- vocal resonance reduced
- severe respiratory distress
- elevated JVP
what is pleural effusion?
collection of fluid in the pleural space can be caused due to an imbalance between hydrostatic and oncotic pressures
-> blood = haemothorax
-> chyle = chylothorax
-> pus = emphysema
what is pleural fluid
- secreted by parietal pleura and drained through parietal pleura lymphatics
-this fluid is maintained between hydrostatic and oncotic pressure
-this fluid maintains the pleural seal and acts as a lubricant
what is a transudate?
low protein content fluid
what is an exudate?
high protein content fluid
what is a plural fluid analysis and what are some things you would look for
- can diagnose the cause of the effusion
things that should be tested for:
LDH
total protein
gram stain
