Symptoms of a collapsed lung include shortness of breath, sharp chest pain that worsens with a cough or a deep breath, and nasal flaring. In severe cases, symptoms include a bluish skin tone from a lack of oxygen, chest tightness, fatigue, and a fast heart rate, explains MedlinePlus.
A collapsed lung is called a pneumothorax, and it happens when air leaks into the space between the lung and the chest wall. The air pushes on the lung and causes it to collapse. Pneumothorax can happen from penetrating chest injuries, secondary to underlying disease, because of medical procedures, or spontaneously, according to MedicineNet.com.
Any chest injury can cause air to leak into the chest wall, and it can happen after a car accident, physical assault, or during a surgical procedure that involves the lung or chest wall. Underlying disease such as COPD, cystic fibrosis and pneumonia increase the risk for pneumothorax because the lungs are weak and susceptible to collapse, according to Mayo Clinic.
Mechanical ventilation is also a common cause of pneumothorax because pressure in the lungs is artificially controlled by a machine, and errors in calibration can damage the lung, explains Mayo Clinic. Spontaneous pneumothorax occurs without any damage or injury but from rupture of a cyst or a bleb on the lung surface, explains MedicineNet.com.