A collapsed lung, also known as a pneumothorax, occurs when air leaks into the space between the lung and the chest wall, causing the lung to collapse. This can happen spontaneously without any known cause (primary spontaneous pneumothorax) or as a result of injury or underlying lung disease (secondary spontaneous pneumothorax).
Quick answers
– Yes, it is possible to have a collapsed lung without realizing it, especially if the collapse is minor or gradual.
– A “silent” collapse may cause few or no symptoms, only being detected later on imaging tests.
– Typical symptoms of a collapsed lung include sudden, sharp chest or shoulder pain, shortness of breath, rapid heartbeat, dry cough, and bluish skin color.
– Risk factors include smoking, family history, COPD, asthma, cystic fibrosis, lung infections, physical trauma, prior pneumothorax, and certain medical procedures.
– Diagnosis involves medical history, physical exam, and imaging tests like x-rays, CT scans, or ultrasound.
– Treatment depends on severity and cause but may include observation, oxygen, needle aspiration, chest tube insertion, or surgery.
– With proper treatment, recovery is often quick, but repeat collapses are common without preventive measures.
What is a collapsed lung?
The lungs are encased in a protective lining called the pleural membrane. The membrane has two thin layers – one around the lung and one lining the inside of the chest cavity. Between these layers is a very small amount of fluid that acts as a lubricant allowing the layers to slide smoothly over one another when breathing.
A pneumothorax or collapsed lung occurs when air leaks into the pleural space between these two layers, causing the lung to collapse away from the chest wall to some degree. This air can come from:
- A breach in the lung itself, allowing air to escape from the airways into the pleural space. This is known as a primary spontaneous pneumothorax and can occur without any precipitating injury.
- A hole or tear in the pleural membrane, often due to trauma to the chest. This causes a secondary spontaneous pneumothorax.
- Medical procedures that intentionally introduce air into the pleural space, such as needle biopsies, mechanical ventilation, or insertion of chest tubes.
What are the symptoms of a collapsed lung?
The symptoms of a collapsed lung depend on the extent of the collapse, how quickly it develops, and the overall health of the individual. They can range from mild to severe or even life-threatening.
Typical symptoms of a pneumothorax include:
- Sudden, sharp chest pain – Usually on one side and may feel worse with breathing
- Shortness of breath – Ranging from mild to severe
- Rapid heart rate
- Dry cough
- Bluish discoloration of the skin (cyanosis) – Due to lack of oxygen
- Collarbone and chest tightness
- Anxiety – From difficulty breathing
In mild cases, symptoms may be subtle. Larger collapses can cause extreme shortness of breath, suffocation, low blood pressure, and respiratory failure.
Can you have a collapsed lung without knowing it?
Yes, it is definitely possible to have a collapsed lung without realizing it, especially if the collapse is minor or develops slowly over time. This is sometimes called a “silent” pneumothorax.
In one study, CT scans detected collapsed lungs in over 20% of adult smokers screened, despite 77% of them having no symptoms at the time.
Some reasons a pneumothorax may go unnoticed include:
- The collapse only involves a small portion of the lung.
- The collapse develops gradually over days or weeks.
- The individual has reduced pain perception from use of medication or smoking.
- There is an unusual tolerance to the symptoms.
- There is an overriding health issue with more obvious symptoms.
- The person lacks healthcare access to get evaluated.
However, even without symptoms, a collapsed lung can progressively worsen and lead to life-threatening complications. Thus, quick recognition and treatment are still important.
Who is at risk for a collapsed lung?
Certain factors increase the risk of having a collapsed lung:
- Smoking – The leading risk factor, thought to weaken lung tissue. Collapses are far more common in smokers.
- Family history – Genetic conditions like Marfan syndrome weaken lung tissues.
- Chronic lung disease – COPD, cystic fibrosis, asthma, pulmonary infections.
- Trauma – Both blunt (like a car accident) and penetrating (like a gunshot wound) can tear the lung or pleura.
- Medical procedures – Needle biopsies, intubation, chest tube insertion can introduce air.
- Prior pneumothorax – Collapses can recur in up to 50% of cases.
- Age – Most common in tall, slender young adults up to age 40.
- Sex – Affects males more often than females.
How is a collapsed lung diagnosed?
If pneumothorax is suspected based on risk factors and symptoms, the doctor will do:
- A medical history – Assessing symptoms, risk factors, and timing of symptom onset.
- A physical exam – Listening to the chest with a stethoscope, assessing breathing effort, checking oxygen levels.
- Imaging tests – X-rays, CT scans, or ultrasound of the chest to visualize lung collapse.
The images allow the doctor to locate the site of the air leak and determine how much of the lung is collapsed. This guides appropriate treatment.
Chest X-ray
A standard chest x-ray is typically the first imaging test ordered when a collapsed lung is suspected. The accumulated air outside the lung appears as a white fringe or edge, pointing away from the collapsed portion of lung.
CT scan
If the diagnosis remains uncertain after a chest x-ray, a CT scan can provide more detail about the location and extent of the collapsed area. It can also help identify accompanying chest injuries or conditions.
Lung ultrasound
Lung ultrasound is increasingly used to diagnose pneumothorax, especially when x-rays are inconclusive. It may detect collapse sooner than x-rays. Ultrasound can also be used at the bedside for continuous monitoring.
How is a collapsed lung treated?
Treatment depends on the severity of symptoms, degree of collapse, and whether it is a first episode or recurrence. Options may include:
- Observation – For small collapses (less than 15%) with minimal symptoms. Repeat imaging done to ensure improvement.
- Oxygen therapy – Given through a mask or nasal cannula to help restore oxygen levels.
- Needle aspiration – A needle and syringe are used to remove air from the pleural space, allowing the lung to re-expand.
- Chest tube – A tube is inserted through the chest wall and left in place, allowing continual drainage of air and fluid.
- Surgery – Done for recurrent collapse or persistent air leaks. Blebs or bullae on the lung are removed and pleural surfaces may be pleated.
Bed rest, pain management, and breathing treatments are also important parts of care. Most people improve quickly within 1-2 weeks, but repeat episodes are common without preventive interventions.
Are there complications from a collapsed lung?
Possible complications of a pneumothorax include:
- Respiratory failure – Severe oxygen deprivation can develop rapidly with a large collapse.
- Shock – From sudden drop in blood pressure.
- Tension pneumothorax – Pressure buildup in the pleural space that can compress the heart and blood vessels.
- Infection – Of the pleural space (empyema) from prolonged chest tube placement.
- Lung collapse recurrence – Occurs in approximately 50% of people after initial episode.
- Heart complications – Low oxygen levels can lead to heart arrhythmias.
With timely treatment, most collapsed lungs will recover without serious complications. But monitoring for signs of worsening severity is important, as is follow-up to prevent recurrence.
How can collapsed lungs be prevented?
For first-time collapses with no clear cause, preventing recurrence focuses on:
- Smoking cessation
- Avoiding air travel until fully recovered
- Gradual return to strenuous exercise
- Maintaining ideal body weight
After a second collapse:
- Pleurodesis may be recommended – gluing the pleural membranes together so no air can enter.
- Less commonly, pleurectomy surgery – removing the pleural lining around the lung.
Treatment guidelines recommend pleurodesis after the second collapse because the recurrence rate approaches 80% otherwise.
What is the outlook for a collapsed lung?
With proper treatment, the outlook for lung collapse is generally very good. Air is reabsorbed from the pleural space within 1-2 weeks in most cases and full recovery is common, especially after a first collapse.
The risks come from unrecognized or undertreated cases progressing to respiratory failure, tension pneumothorax, or other life-threatening complications. But such outcomes are preventable with prompt diagnosis and management.
The main challenge after recovery is preventing recurrence, especially in those with chronic lung disease or repeat episodes. Quitting smoking and allowing full healing before air travel or strenuous exercise can help maintain lung health.
Mortality rates for collapsed lung
Overall mortality rates are low, with death being unlikely when collapsed lungs are recognized early and treated.
One study found mortality rates for spontaneous pneumothorax as follows:
- Primary spontaneous pneumothorax – 1% mortality
- Secondary pneumothorax – 6% mortality
- Tension pneumothorax – 25-50% mortality untreated. Still 5-10% mortality despite treatment.
Higher mortality is associated with underlying lung disease, greater lung collapse, older age, hemodynamic instability, need for mechanical ventilation, and tension physiology.
Conclusion
A collapsed lung or pneumothorax can occasionally go unnoticed if symptoms are mild or minimal. But even “silent” collapses warrant treatment to prevent progression and avoid complications like respiratory failure. Prompt diagnosis relies on imaging tests like x-rays, CT scans or ultrasound when symptoms or risk factors are present. With proper management and follow-up care, most people recover fully within 1-2 weeks.