A pneumothorax, commonly referred to as a collapsed lung, occurs when air leaks into the space between the lung and the chest wall (the pleural cavity). Normally, this space maintains negative pressure, keeping the lung fully inflated. When air accumulates, it creates positive pressure that overcomes the lung’s elasticity, causing it to partially or completely deflate. This prevents the lung from expanding properly, impairing oxygenation and ventilation. The condition can range from minor to life-threatening, and treatment focuses on relieving pressure to allow the lung to re-expand and prevent recurrence.
Understanding the Collapsed Lung
The mechanics of a collapsed lung involve disrupting the pressure balance within the chest cavity. The lung is encased by two thin membranes: the visceral pleura (covering the lung) and the parietal pleura (lining the chest wall). The space between them, the pleural cavity, is normally kept at negative pressure, which holds the lung open.
When a hole or tear develops, air enters the pleural space, neutralizing the negative pressure and causing the lung to collapse. Air entry determines the type: spontaneous pneumothorax results from a leak in the lung, while traumatic pneumothorax results from an external injury.
Pneumothoraces are categorized by cause to guide treatment. A primary spontaneous pneumothorax (PSP) occurs in people without underlying lung disease, often due to the rupture of small air-filled sacs called blebs. A secondary spontaneous pneumothorax (SSP) happens in patients with pre-existing lung conditions, such as Chronic Obstructive Pulmonary Disease (COPD) or cystic fibrosis.
Traumatic pneumothorax results from blunt or penetrating chest injuries, including medical procedures. The most dangerous form is a tension pneumothorax, where air enters the pleural space but cannot escape, causing rapid pressure buildup. This escalating pressure pushes chest structures, including the heart, to the opposite side, leading quickly to severe circulatory and respiratory failure.
Recognizing the Emergency and Seeking Care
A pneumothorax typically presents with sudden, sharp pain on one side of the chest that worsens with inhalation. This is accompanied by shortness of breath, varying with the size of the collapse. Other signs include rapid breathing and an accelerated heart rate as the body compensates for reduced lung function.
If a tension pneumothorax develops, symptoms intensify rapidly, including severe distress, low blood pressure, and a bluish tint to the skin or lips due to lack of oxygen. Any sudden chest pain or difficulty breathing requires immediate medical attention. The person should be transported to the nearest emergency department or emergency services should be called.
Initial stabilization focuses on supporting breathing and circulation. Supplemental oxygen is often administered, which helps speed up the absorption of trapped air in stable cases. For suspected tension pneumothorax, medical professionals immediately perform needle decompression before definitive imaging. This procedure involves inserting a large-bore needle into the chest wall to release the trapped air, converting the life-threatening tension into a simple pneumothorax.
Clinical Methods for Lung Re-inflation
The strategy for re-inflating the lung depends on the size of the pneumothorax, symptoms, and presence of underlying lung disease. For a very small pneumothorax in a stable patient, the first approach may be simple observation. The air is expected to reabsorb naturally over several weeks, monitored by serial chest X-rays to ensure re-expansion.
For larger or more symptomatic collapses, active air removal is required to relieve pressure. Simple aspiration is a minimally invasive technique often used for initial treatment of primary spontaneous pneumothorax. A hollow needle and catheter are inserted between the ribs into the pleural space. A syringe is then attached to actively pull the trapped air out, allowing the lung to re-inflate.
When aspiration is insufficient or the pneumothorax is large, tube thoracostomy (chest tube insertion) is performed. A flexible tube is placed into the pleural space and connected to a one-way valve drainage system. This system allows air to escape continuously while preventing re-entry, encouraging lung re-expansion. The chest tube remains in place for several days until the air leak is sealed and the lung is fully expanded.
Surgical intervention is necessary for persistent air leaks, recurrent pneumothoraces, or when the lung fails to re-expand after chest tube drainage. Video-Assisted Thoracoscopic Surgery (VATS) is the most common surgical approach, involving small incisions and specialized cameras. During VATS, surgeons identify and seal the source of the air leak, such as a bleb on the lung surface, often by stapling or resecting the affected area.
To reduce the risk of recurrence associated with spontaneous pneumothorax, a procedure called pleurodesis is often performed during surgery. Pleurodesis involves intentionally irritating the outer lung surface and the chest wall lining so they scar and adhere. This obliteration of the pleural space prevents the lung from collapsing again. This can be achieved mechanically by abrading the pleura, or chemically by introducing an irritant like talc or doxycycline.
Recovery and Preventing Recurrence
Following a procedure to re-inflate the lung, patients are typically hospitalized for a few days for observation and pain management. A hospital stay is important after chest tube insertion to monitor the drainage system and ensure the air leak has resolved. Pain management is crucial, often involving analgesics or intercostal nerve blocks, as the chest tube can cause significant discomfort.
Long-term recovery involves patient education regarding lifestyle modifications and the risk of recurrence. For spontaneous pneumothorax, recurrence rates can be as high as 32% without definitive intervention, with most repeat episodes occurring within the first year. Quitting smoking is the most effective action to lower the likelihood of recurrence, as tobacco use is a major risk factor.
Patients are advised to avoid activities involving significant pressure changes for several weeks or months after the event. This includes abstaining from air travel immediately post-procedure and permanently avoiding deep-sea diving. Follow-up imaging, such as repeat chest X-rays, is routinely scheduled after discharge to confirm sustained lung expansion and monitor for signs of a new collapse.