Atelectasis
Condition
(Collapsed Lung)
Definition
Atelectasis is a collapse of the air sacs in the lungs. It may occur in part or all of the lung. It can make it hard to breathe.
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Causes
Atelectasis is caused by:
- A blocked airway, such as from a foreign body, mucus plug, or tumor
- Pressure outside the airway, such as from:
- Injury
- Scarring
- Fluid buildup
- Infection
- Suppressed breathing or coughing
- Reduced surfactant—a fluid that keeps the lungs expanded
Risk Factors
Things that may raise the risk of atelectasis are:
- Premature birth—if lungs are not fully developed
- Anesthesia
- Injuries and health problems that limit physical activity
- Weak breathing muscles
- Mechanical ventilation
- Lung diseases, such as asthma, cystic fibrosis, or lung cancer
- Smoking
- Heart failure
- Obesity
Symptoms
Some people may not have symptoms. A large area of collapse is more likely to cause symptoms. Problems may be:
- Breathing that is fast, difficult, or shallow
- Coughing
- Mild fever
- Fast heart rate
- Chest pain
- Blueness of the lips or nails
Diagnosis
The doctor will ask about symptoms and health history. A physical exam will be done. This will include listening to lung sounds.
The airways will need to be viewed. This can be done with:
Other tests may be needed to find a cause.
Treatment
Mild atelectasis often goes away on its own without treatment. In others, the goal is to treat the underlying cause and maintain enough oxygen. The collapsed lung usually expands when the cause has been corrected.
Therapy
Therapy will be needed to help with breathing, such as:
- Physical therapy—to help clear mucus from the lung
- Oxygen—to assist with breathing
- Respiratory therapy, such as:
- Breathing masks or treatments—to keep the airway open
- Incentive spirometry—to promote deep breathing
- Suction—to help remove fluid and mucus build up
- Mechanical ventilation—in people who cannot breathe on their own
Medicine
Medicine may be given to:
- Open airways
- Treat the condition that caused atelectasis
- Fight infections
Procedure
A bronchoscopy may be done to remove a foreign body from the lung.
Prevention
To lower the risk of atelectasis:
- Avoid smoking
- Reach or maintain a healthy weight
- Manage chronic heart or lung problems
American Lung Association
National Heart, Lung, and Blood Institute
CANADIAN RESOURCES:
Health Canada
The Lung Association
American Lung Association
National Heart, Lung, and Blood Institute
CANADIAN RESOURCES:
Health Canada
The Lung Association
References
- Atelectasis. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/pulmonary-disorders/bronchiectasis-and-atelectasis/atelectasis.
- Chest x-ray patterns in the differential diagnosis of lung disorders. EBSCO DynaMed website. Available at: https://www.dynamed.com/evaluation/chest-x-ray-patterns-in-the-differential-diagnosis-of-lung-disorders.
- Respiratory distress syndrome (RDS). National Heart, Lung, and Blood Institute website. Available at: https://www.nhlbi.nih.gov/health/respiratory-distress-syndrome.
- Marini JJ. Acute lobar atelectasis. Chest. 2019;155(5):1049-1058.
Contributors
- David L. Horn, MD, FACP
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