A collapsed lung, or pneumothorax, occurs when air leaks into the pleural space, the area between the lung and the chest wall. This air buildup disrupts the normal mechanics of breathing, causing pressure to build and the lung to shrink. Because a pneumothorax interferes with the body’s ability to exchange oxygen and carbon dioxide, it requires prompt medical attention.
Understanding the Mechanism of Lung Collapse
The lung remains inflated due to a pressure balance within the chest cavity. Normally, the pleural space maintains a slight negative pressure, which keeps the lung tissue expanded against the chest wall. The lung has a natural tendency toward elastic recoil, but this negative pressure counteracts that force.
A pneumothorax occurs when a hole develops in the lung tissue or the chest wall, allowing air to enter the pleural space. This air inflow equalizes the pressure within the pleural space to atmospheric pressure. Without the necessary negative pressure, the lung’s natural elastic forces cause it to collapse inward.
The causes of this air leak fall into three main categories:
- Primary spontaneous pneumothorax (PSP) happens in individuals without underlying lung disease, typically due to the rupture of small, air-filled sacs called blebs or bullae.
- Secondary spontaneous pneumothorax (SSP) occurs in people with pre-existing conditions, such as severe emphysema from Chronic Obstructive Pulmonary Disease (COPD) or cystic fibrosis.
- Traumatic pneumothorax results from an external injury, such as a fractured rib puncturing the lung or a penetrating chest wound.
Recognizing the Symptoms and Severity
Symptoms are typically marked by the sudden onset of sharp, stabbing chest pain on the affected side. This pain often intensifies when inhaling deeply or coughing. It is almost always accompanied by shortness of breath, which can range from mild difficulty breathing to severe respiratory distress.
A rapid heart rate is a common response as the body attempts to compensate for reduced oxygen intake. In severe cases, a bluish tint to the skin and lips, known as cyanosis, can appear, signaling dangerously low oxygen levels.
A specific, life-threatening form is the tension pneumothorax, where a one-way valve effect allows air to enter the pleural space but prevents it from escaping. The resulting rapid pressure buildup pushes the chest structures toward the opposite side. This shift severely restricts blood return to the heart, leading to a sudden drop in blood pressure and circulatory collapse.
Immediate Diagnosis and Treatment Procedures
Diagnosis typically begins with imaging studies. A standard chest X-ray is often sufficient to confirm the condition, revealing a visible pleural line and the absence of lung tissue markings beyond it. CT scans may be used to provide a more detailed view or to identify blebs that caused a spontaneous collapse.
Treatment is determined by the size of the collapse and the patient’s stability. For a small pneumothorax in a stable patient, observation and supplemental oxygen may be sufficient care. This allows the trapped air to be gradually reabsorbed. If the collapse is large or causing significant symptoms, intervention is required to remove the air.
For a tension pneumothorax, the emergency procedure is immediate needle decompression, where a large-bore needle is inserted into the chest wall to release the trapped air. Following stabilization, or for less urgent large collapses, a chest tube insertion is performed. This involves placing a tube between the ribs into the pleural space and connecting it to a drainage system with an underwater seal. This system allows air to exit the chest cavity continuously until the lung re-expands fully.
If the condition recurs or fails to heal, surgical procedures are considered to prevent future episodes. The most common technique is Video-Assisted Thoracoscopic Surgery (VATS), where a surgeon uses small incisions to remove any ruptured blebs. This is often combined with pleurodesis, a technique that causes the lung lining to stick to the chest wall. Pleurodesis can be mechanical, involving abrasion of the chest wall lining, or chemical, using an irritant like talc slurry to induce adhesion.
Recovery and Preventing Future Episodes
Recovery time varies depending on the initial treatment. Patients who receive a chest tube typically require a hospital stay of a few days. For small collapses treated with observation, the lung may take a few weeks to fully re-expand as the air is absorbed. Surgical patients typically face a recovery period of several weeks before returning to full activity.
Preventing recurrence is a primary focus of post-treatment care, as the risk of a second collapse is high after a first episode. The most effective preventative measure is permanent smoking cessation. Patients are also advised to avoid activities that involve significant changes in air pressure.
Commercial air travel is restricted for a period following treatment. Scuba diving is often permanently discouraged due to the extreme risk of a fatal tension pneumothorax. Follow-up care with repeat chest X-rays is necessary to ensure the lung remains fully inflated and to monitor for recurrence.