Pneumothorax
Pneumothorax is air in the pleural space, occurring spontaneously (primary in structurally normal lungs, secondary in underlying lung disease) or from trauma or procedures. Management is driven by size and hemodynamic stability, ranging from observation to needle aspiration to tube thoracostomy.
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What this article covers
- Overview
Air in the pleural space: pneumothorax occurs when air enters the potential space between the visceral and parietal pleura, collapsing the underlying lung and disrupting the normal negative…
- Epidemiology
Sex and age skew for PSP: primary spontaneous pneumothorax occurs mainly in tall, thin young men without any recognized underlying lung disease.
- Risk factors
Smoking (PSP and SSP): the single most important modifiable risk factor for both primary and secondary spontaneous pneumothorax.
- Pathophysiology
Loss of the normal negative pleural pressure: the pleural space normally sits at subatmospheric pressure, keeping the lung expanded against its elastic recoil; entry of air abolishes this gradient and the lung collapses toward the hilum.
- Clinical features
Sudden-onset pleuritic chest pain and dyspnea: the hallmark presentation, typically abrupt in onset and often occurring at rest.
- Differential diagnosis
Tension pneumothorax: distinguished by hemodynamic compromise (hypotension, distended neck veins, tracheal deviation) rather than size alone; treated emergently, not with imaging first.
- Diagnosis
Confirmed by chest imaging showing a visceral pleural line with absent lung markings peripheral to it; size is graded by the distance from the lung margin to the chest wall at the hilum on chest…
- Management
First, determine hemodynamic stability. Cardiovascular compromise (hypotension, increasing breathlessness) of any size mandates immediate management as tension pneumothorax with emergent needle…
- Complications
Tension pneumothorax: progression to hemodynamically significant obstructive physiology, requiring immediate needle decompression; discussed fully in its own entity.
- Prognosis
Recurrence dominates the long-term outlook: PSP recurs in 23-50% of patients within 1-5 years, and SSP recurs in more than 50% of patients within 1-3 years, without a recurrence-prevention procedure.
- Prevention
Recurrence-prevention intervention is indicated after the second ipsilateral episode of PSP, and after the first episode of SSP, and is also reasonable after a first PSP episode in a high-risk occupation (diving, aviation).
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