20 - Pneumothorax and Pleural Effusion Flashcards
Define the following terms:
- Simple pneumothorax
- Tension pneumothorax
- Primary pneumonthorax
- Spontaneous pneumothorax
- Iatrogenic pneumothorax
- Simple: presence of air in the pleural space due to lung or chest wall trauma
- Tension: air is trapped in the pleural space compressing the lungs and decreasing venous return. causes mediastinal shift and CVS collapse
- Primary spontaneous: occurs in the absence of lung disease
- Secondary: due to lung disease or trauma
- Iatrogenic: high pressure ventilation, central line placement
What group of people does a primary spontaneous pneumothorax most commonly occur in?
- Young tall thin males with no history of lung disease or trauma
- Rupture of small subpleural bleb is most common cause
What are some causes of a secondary pneumothorax?
What are some signs and symptoms of a pneumothorax?
- History: sudden onset of pleuritic chest pain and breathlessness
- Examination: affected side has reduced chest movement, hyper resonant percussion and recuded breath sounds/vocal resonance
- CXR: hyperlucent side on pneumothorax and absent lung markings
- Tension: severe respiratory distress, tachypnoea, tracheal shift, tachycardia, hypotension
How do you treat a simple pneumothorax?
- Asymptomatic will seal alone
- Symptomatic:
Small: needle aspiration
Large: insert chest drain with underwater seal into the safe triangle. Check it is bubbling and remove chest drain once lung is fully expanded
Why is tension pneumothorax so dangerous?
- Mediastinal shift compresses normal lung so venous return is impaired, cardiac output drops so CVS collapse
What signs in the history would indicate a tension pneumothorax?
- Diagnosis is clinical, cannot wait for CXT
- Need emergency needle decompression
How do you treat a tension pneumothorax differently to a normal pneumothorax?
- Insert a plastic cannula into 2nd intercostal space mid clavicular line to release air
- Leave cannula in place until chest drain can be inserted when patient is more stable
NEEDLE DECOMPRESSION
What is a pleural effusion?
- Excess of fluid in the pleural cavity due to lack of lymphatic drainage in the parietal pleura or hypersecretion from visceral pleura
What are the different categories of pleural effusion?
- Do a pleural aspiration to diagnose
- Effusion: transudate or exudate
- Haemothorax
- Chylothorax
- Empyema
What are some causes of transudate and exudate pleural effusions?
Transudate
- Increased pleural capillary hydrostatic pressure due to congestive heart failure
- Decreased capillary oncotic pressue due to cirrhosis or nephrotic syndrome
Exudate
- Increase capillary permeability e.g TB, bronchial carcinoma, pneumonia
How can you tell the difference between a transudate and exudate pleural effusion?
- Light’s criteria
- Transudate will have a low pleural fluid LDH and protein
- Exudate will have high pleural fluid LDH and protein
- Can help diagnosis if you know which one
What are some signs and symptoms of a pleural effusion?
- Gradual onset breathlessness and pleuritic chest pain
- Reduced chest movement on affected sife
- Dull resonance on affected side
- Absent breath sounds
How can we diagnose pleural effusions?
- History
- Examination
- CXR with opacity in lower zone and upper border meniscus
- CT to confirm pathology
- Diagnostic aspiration with ultrasound guidance. Test for LDH, protein, bacteria and cytology
How can you tell if there is a bilateral pleural effusion?
Blunting of costophrenic angles, usually due to a transudate