Pneumothorax

A pneunothorax is a collection of air in the pleural cavity.  The main subdivisions are:

• primary spontaneous pneumothorax = occurring in a healthy individual
• secondary spontaneous pneumothorax = occurring in an individual with underlying lung disease
• traumatic pneumothorax = shouldn't be managed by medics!

Classical symptoms: dyspnoea and chest pain.

Classical signs: reduced breath sounds, reduced chest expansion and hyperresonance on the side of the pneumothorax.  Rarely a 'clicking' sound at the cardiac apex.

Risk of pneumothorax is increased in:

• smokers
• tall people
• HIV infection (believed to be due to pneumocystis jiroveci) 

Pneumothorax is not usually associated with exercise

Conditions predisposing to development of a secondary pneumothorax include:

• COPD
• asthma
• interstitial lung diseases
• lung infection
• connective tissue diseases such as
• rheumatoid arthritis
• Ehlers-Danlos
• Marfans syndrome

The BTS guidelines on the management of spontaneous pneumothorax are summarised in the diagrams below:

An unusual form of pneumothorax is a catamenial pneumothorax.  This is pneumothorax in women occurring usually within 72 hours before or after menstruation, associated with chest pain, dyspnoea and haemoptysis.  It is believed to be due to ectopic endometriosis.

Small print gem: although a tension pneumothorax is classically decompressed in the 2nd intercostal space, a 14G venflon will not be long enough to reach the parietal pleural in a third of patients, in which case the 4th or 5th intercostal space should be used.

References

Curry, G. et al. Pneumothorax: an update. Postgrad Med J. 2007; 83(981): 461-465.
MacDuff et al. Management of spontaneous pneumothorax. British Thoracic Society pleural disease guideline 2010. Thorax. 65(Suppl 2):ii18-31.