This is when air leaks into the space between your lungs and chest wall, causing some or all of a lung to collapse. Various types of pneumonia, which is a lung infection, can cause atelectasis. This condition involves the buildup of fluid in the space between the lining of your lungs and the inside of your chest wall. This can lead to the squeezing of your lungs. Chest trauma, such as from a fall or car accident, can cause you to avoid taking deep breaths due to pain. Possible causes of atelectasis due to pressure from outside the lung include: A growth, which may or may not be cancer, can narrow or block the airway. Atelectasis is common in children who have inhaled an object into their lungs, such as a peanut or part of a small toy. Mucus plugs also are common in children, people with cystic fibrosis and during severe asthma attacks. Suctioning the lungs during surgery helps clear them. So mucus that usually would move out of your lungs may build up in your airways. Drugs given during surgery make you breathe less deeply.

It commonly occurs during and after surgery because you can't cough.

A mucus plug is a buildup of sputum or phlegm in your airways. When a blocked airway causes atelectasis, it may be due to: It often occurs after heart bypass surgery. Nearly everyone who has major surgery has some amount of atelectasis. This can cause the air sacs in your lungs to lose air. It changes your regular pattern of breathing and affects the exchange of lung gases. General anesthesia - which brings on a sleeplike state with the use of medicines before a procedure or surgery - is a common cause of atelectasis. This is called nonobstructive atelectasis. Pressure from outside the lung also can cause atelectasis.

Wheeze lung sounds