Pneumothorax**** Flashcards
Pathophysiology:
A defect in the visceral pleura causes air to enter the pleural space from the lungs.
The recoil of the lungs causes the lung to deflate and collapse.
What is a simple pneumothorax?
How does a tension pneumothorax work? - 4 steps
Non-expanding collection of air
- A communication is made with the lungs and pleural space (maybe due to stab wound or blunt trauma causing rib fracture to puncture lung)
- This communication acts as a one-way valve, allowing air into the pleural space but not allowing any air out.
- Air builds up in the pleural space.
- Pushes mediastinum over to the contralateral side.
Causes:
Primary spontaneous:
- What type of person does this happen in?
- What ruptures causing these?
Secondary spontaneous (due to lung disease):
- List some chronic or acute lung diseases that could cause this? - 7
- What connective tissue disorders can also cause this? - 2
What type of trauma may cause this?
Why does mechanical ventilation cause a pneumothorax?
Young thin men
Subpleural bulla ==== Asthma COPD TB Pneumonia Lung cancer Cystic fibrosis ILD
Marfans syndrome
Ehlers-Danlos syndrome
Blunt trauma - rub fracture
Stab wound
In patients requiring intensive care, a pneumothorax is often caused by barotrauma associated with mechanical ventilation in the presence of reduced lung compliance. The initial process in barotrauma is the production of perivascular interstitial emphysema.
Symptoms:
Who can be asymptomatic?
Main symptoms?
How may patients with asthma or COPD present?
Signs on examination:
- Expansion
- Percussion
- Breath sounds
- One main sign of severe tension pneumothorax
If young and fit with small pneumothoraces
Acute-onset SOB
Pleuritic chest pain
Sudden deterioration ==== Reduced expansion on the affected side Hyperresonant percussion on the affected side - more air Reduced BS on the affected side
Deviated trachea
Why is a tension pneumothorax a medical emergency? - 4
Compression of both lung - hypoxia
Compression of the great veins
Compression of heart - reduced filling
Impaired venous return - as there is more air in the thorax, there is increased positive pressure - so less sucking back in of blood during inspiration.
Signs of tension pneumothorax? - name 5
What investigation should be skipped if there is a suspected tension pneumothorax?
Trachea deviated away from the side of the pneumothorax
Resp distress - compression of lungs
Tachycardia - compensating for reduced filling
Hypotension - reduced filling
Distended neck veins - reduced filling
CXR
https://www.youtube.com/watch?v=95IhCXDL9EY
Investigations:
What imaging is done if CXR is uncertain?
What imaging should be done for those who are suprine due to trauma?
CT
USS
Management - Primary pneumothorax:
How many cms between the lungs and chest wall at the level of the hilum is classed as a small pneumothorax on CXR and only needs conservative Rx?
If it is NOT small, there are 2 options, needle aspiration and a chest drain. Which one is done first, and if unsuccessful, the other is done?
<2cm
Needle aspiration > chest drain
Management - Secondary pneumothorax:
How many cms between the lungs and chest wall at the level of the hilum is can be managed conservatively?
If it is between 1-2cm, what is tried first?
If it is >2cm and SOB, what is done?
<1cm
Needle aspiration
Chest drain
Management - Tension pneumothorax:
What is done first for symptomatic relief?
Needle aspiration then chest drain
Surgical Advice:
When should surgery be considered?
Bilateral
Lung fails to expand within 48 hrs
Persistent air leak
2/more previous pneumothoraces on the same side
Procedures - Needle Aspiration (Thoracocentesis):
Where is it done?
What type of cannula is used?
What should be attached to the cannula for a simple pneumothorax?
What should be done for a tension pneumothorax which provides instant relief?
Lower 2nd intercostal space - mid-clavicular line
Large bore cannula - 16-18G - look up
Attach a tap and syringe for aspiration
Removal of stylet
Procedures - Chest drain:
What is the area the chest drain is put in, called?
Where is it done?
What is given for pain?
What type of imaging needs to be done if this was for pleural effusion?
The triangle of safety
4th or 5th intercostal space, anterior to the mid-axillary line
Lidocaine until pleural space
US-guided drain
