Pneumothorax Flashcards
Describe the causes of pneumothorax
- Spontaneous -
- Primary - No lung disease
- Secondary - Existing lung disease or age>50 and smoker - Traumatic - Fractured rib, blunt chest trauma, penetrating injuries
- Iatrogenic - High pressure ventilation, post central line or pacemaker insetion
- Tension - Emergency
What are some risk factors for pneumothorax?
- Pre-existing lung disease
- Height
- Smoking cannabis
- Diving
- Trauma/chest procedure
- Association with other conditions eg Marfan’s syndrome
How does a primary spontaneous pneumothorax occur?
A small sub pleural bleb/bulla bursts, allowing air into the pleural cavity
What is the pathophysiology of a pneumothorax?
- The chest wall or lung becomes breaches
- A communication is created between the pleural space and the atmosphere
- Air flows into the pleural cavity, down a pressure gradients
- Lung collapses due to unopposed elastic recoil as loss of negative pressure in the pleural space
What is a tension pneumothorax?
Any size of pneumothorax causing mediastinal shift and cardiovascular collapse
How does a tension pneumothorax occur?
Air can enter the pleural cavity on inspiration, but cannot escape during expiration. The flap acts like a one way valve.
How does a tension pneumothorax cause hypoxaemia?
There is no partial pressure gradient of oxygen so it is hard for air to enter the lungs.
How does a tension pneumothorax cause HD compromise?
Venous return is impaired so cardiac output drops.
What are some symptoms of pneumothorax?
- May be asymptomatic
- Sudden onset dyspnoea/pleuritic chest pain
- Patients with asthma/COPD present with a sudden deterioration
What are some signs of pneumothorax?
- Reduced chest expansion
- Hyperresonant percussion
- Diminished breath sounds on affected side
- Reduced vocal resonance on affected side
What are signs of pneumothorax on a CXR?
- Hyperlucent chest
- Absent lung markings
- Edge of collapsed lung can be seen
What are signs of a tension pneumothorax on a CXR?
- Hyperlucent chest
- Absent lung markings
- Edge of collapsed lung can be seen
- Deviated trachea
- Heart displaced to the left
What are symptoms of a tension pneumothorax?
- Severe chest pain and dyspnoea
- Pleuritic chest pain
- Fatigue
- Tachycardia, raised JVP
- Absent breath sounds
MOST IMPORTANT - Deviated trachea and displaced apex beat
How do you manage a primary spontaneous pneumothorax in a patient that is >2cm and/or breathless?
Aspirate 16-18G cannula.
Aspirate less than 2.5L.
Give O2.
If they remain symptomatic, insert a chest drain and admit.
How do you treat a secondary spontaneous pneumothorax in a patient that is >2cm or breathless?
Insert chest drain, and admit.
Have a lower threshold for ICD than with a primary pneumothorax.
