Pneumothorax
A pneumothorax is air in the pleural space causing partial or complete lung collapse. Emergency management is driven by physiology (presence of tension), cause (primary, secondary, traumatic/iatrogenic), size on imaging and the patient’s symptoms and comorbidity.
The British Thoracic Society guidance (BTS 2023) is commonly used as an operational framework for spontaneous pneumothorax; Resuscitation Council UK, NICE NG39 (major trauma), RCEM procedural guidance and MHRA device advice inform acute, trauma and procedural practice.
Pathophysiology and classification
- Loss of negative intrapleural pressure allows lung recoil and collapse.
- A one‑way valve mechanism produces tension physiology with rising intrathoracic pressure, mediastinal shift and cardiovascular compromise.
Clinical categories
- Primary spontaneous pneumothorax (PSP): occurs without known underlying lung disease (classically young, slim smokers).
- Secondary spontaneous pneumothorax (SSP): occurs with established lung disease (COPD, cystic fibrosis, interstitial lung disease, opportunistic infection). SSP carries higher clinical risk for the same radiological size.
- Traumatic / iatrogenic pneumothorax: follows blunt or penetrating injury or procedural complication (central line insertion, lung biopsy, mechanical ventilation).
- Tension pneumothorax: a clinical syndrome of cardiorespiratory compromise - a life‑threatening emergency.
Presentation and clinical features
- Typical symptoms: sudden pleuritic chest pain, dyspnoea and cough; PSP may be minimally symptomatic while SSP is usually more symptomatic.