Atelectasis likely won't cause signs or symptoms if it only affects a small area of lung.
If atelectasis affects a large area of lung, especially if it occurs suddenly, it may cause a low level of oxygen in your blood. As a result, you may feel short of breath. Your heart rate and breathing rate may increase, and your skin and lips may turn blue.
Other symptoms might be related to the underlying cause of the atelectasis (for example, chest pain due to surgery).
If your child has atelectasis, you may notice that he or she seems agitated, anxious, or scared.
The NHLBI updates Health Topics articles on a biennial cycle based on a thorough review of research findings and new literature. The articles also are updated as needed if important new research is published. The date on each Health Topics article reflects when the content was originally posted or last revised.