Pneumothorax

Question 1

How common is it?

Answer 1

• ~2 in 10,000 adults in UK get pneumothorax each year.

Question 2

Who does it affect?

Answer 2

• Most occur in healthy young adults with no lung disease. Common in tall thin people.
• Men affected 4 times more than women.
• Rare in people over the age of 40.
• Much more common in cigarette smokers than non-smokers.

Question 3

What causes it?

Answer 3

• Collection of air in pleural space surrounding lung.
• Often spontaneous (especially in thin young men) due to rupture of sub-pleural bulla.
• Other causes: asthma; COPD; TB; pneumonia; lung abscess; carcinoma; CF; lung fibrosis; sarcoidosis; CT disorders (Marfan’s sy., Ehlers-Danlos sy.), trauma; iatrogenic (subclavian CVP line insertion, pleural aspiration/biopsy, transbronchial biopsy, liver biopsy, +ve pressure ventilation).
• TENSION PNEUMOTHORAX – Air drawn into pleural space with each inspiration has no route of escape during expiration. Mediastinum pushed over into contralateral hemithorax, kinking and compressing the great veins. Unless air is rapidly remove, cardiorespiratory arrest will occur.

Question 4

What risk factors are there (and how can they be reduced)?

Answer 4

Chronic lung disease (COPD, CF, lung fibrosis, sarcoidosis), Infection (TB, pneumonia, lung abscess), trauma, carcinoma, connective tissue disorders.

Question 5

How does it present?

Answer 5

Symptoms

• There may be no symptoms (especially if fit, young and small pneumothorax) or there may be sudden onset of dyspnoea and/or pleuritic chest pain.
• Patients with asthma or COPD may present with a sudden deterioration.
• Mechanically ventilated patients may present with hypoxia or an increase in ventilation pressures.

Signs

• Reduced expansion; hyper-resonanceto percussion and diminished breath sounds on affected side.
• With a tension pneumothorax, the trachea will be deviated away from the affected side.

Question 6

How would you investigate the patient?

Answer 6

• CXR (NOT IF TENSION PNEUMOTHORAX) – look for area devoid of lung markings, peripheral to edge of collapsed lung.
• Ultrasound?
• CT in unusual cases
• ABG will show hypoxia.

Question 7

What treatment/s would you consider? What risks and benefits of treatment are there?

Answer 7

Always give oxygen. Other treatment depends on whether it is a primary or secondary pneumothroax, size and symptoms:
- Pneumothorax due to trauma or mechanical ventilation requires a chest drain.
- Surgical – if bilateral pneumothoraces; lung fails to expand after intercostal drain insertion; 2 or more previous pneumothoraces on same side, or history of pneumothorax on opposite side.
For tension pneumothorax:
- Large needle in 2nd intercostal space, mid-clavicular line on side of suspected pneumothorax (decompression). Then insert a chest drain.
- Do this before requesting a CXR.