A<unk>  is an abnormal collection of air in the pleural space between the lung and the chest wall. Symptoms typically include sudden onset of sharp, one-sided chest pain and shortness of breath. In a minority of cases, a one-way valve is formed by an area of damaged tissue, and the amount of air in the space between chest wall and lungs increases; this is called a tension<unk> . This can cause a steadily worsening oxygen shortage and low blood pressure. This leads to a type of shock called obstructive shock, which can be fatal unless reversed. Very rarely, both lungs may be affected by a<unk> . It is often called a "collapsed lung", although that term may also refer to atelectasis. A primary spontaneous<unk>  is one that occurs without an apparent cause and in the absence of significant lung disease. A secondary spontaneous<unk>  occurs in the presence of existing lung disease. Smoking increases the risk of primary spontaneous<unk> , while the main underlying causes for secondary<unk>  are COPD, asthma, and tuberculosis. A traumatic<unk>  can develop from physical trauma to the chest (including a blast injury) or from a complication of a healthcare intervention. Diagnosis of a<unk>  by physical examination alone can be difficult (particularly in smaller<unk> es). A chest X-ray, computed tomography (CT) scan, or ultrasound is usually used to confirm its presence. Other conditions that can result in similar symptoms include a hemothorax (buildup of blood in the pleural space), pulmonary embolism, and heart attack. A large bulla may look similar on a chest X-ray. A small spontaneous<unk>  will typically resolve without treatment and requires only monitoring. This approach may be most appropriate in people who have no underlying lung disease. In a larger<unk> , or if there is shortness of breath, the air may be removed with a syringe or a chest tube connected to a one-way valve system. Occasionally, surgery may be required if tube drainage is unsuccessful, or as a preventive measure, if there have been repeated episodes. The surgical treatments usually involve pleurodesis (in which the layers of pleura are induced to stick together) or pleurectomy (the surgical removal of pleural membranes). About 17–23 cases of<unk>  occur per 100,000 people per year. They are more common in men than women.
Pneumothorax
Hemothorax
Pneumatosis
Chylothorax
Costochondritis
Urinothorax
Traumatic cardiac arrest
Hydropneumothorax