Pneumothorax | |
---|---|
Other names | Collapsed lung[1] |
Illustration depicting a collapsed lung or pneumothorax | |
Specialty | Pulmonology, thoracic surgery |
Symptoms | Chest pain, shortness of breath, tiredness[2] |
Usual onset | Sudden[3] |
Causes | Unknown, trauma[3] |
Risk factors | COPD, tuberculosis, smog, smoking[4] |
Diagnostic method | Chest X-ray, ultrasound, CT scan[5] |
Differential diagnosis | Lung bullae,[3] hemothorax[2] |
Prevention | Smoking cessation[3] |
Treatment | conservative, needle aspiration, chest tube, pleurodesis[3] |
Frequency | 20 per 100,000 per year[3][5] |
A pneumothorax is an abnormal collection of air in the pleural space between the lung and the chest wall.[3] Symptoms typically include sudden onset of sharp, one-sided chest pain and shortness of breath.[2] 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 pneumothorax.[3] 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.[3] Very rarely, both lungs may be affected by a pneumothorax.[6] It is often called a "collapsed lung", although that term may also refer to atelectasis.[1]
A primary spontaneous pneumothorax is one that occurs without an apparent cause and in the absence of significant lung disease.[3] A secondary spontaneous pneumothorax occurs in the presence of existing lung disease.[3][7] Smoking increases the risk of primary spontaneous pneumothorax, while the main underlying causes for secondary pneumothorax are COPD, asthma, and tuberculosis.[3][4] A traumatic pneumothorax can develop from physical trauma to the chest (including a blast injury) or from a complication of a healthcare intervention.[8][9]
Diagnosis of a pneumothorax by physical examination alone can be difficult (particularly in smaller pneumothoraces).[10] A chest X-ray, computed tomography (CT) scan, or ultrasound is usually used to confirm its presence.[5] Other conditions that can result in similar symptoms include a hemothorax (buildup of blood in the pleural space), pulmonary embolism, and heart attack.[2][11] A large bulla may look similar on a chest X-ray.[3]
A small spontaneous pneumothorax will typically resolve without treatment and requires only monitoring.[3] This approach may be most appropriate in people who have no underlying lung disease.[3] In a larger pneumothorax, 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.[3] Occasionally, surgery may be required if tube drainage is unsuccessful, or as a preventive measure, if there have been repeated episodes.[3] 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).[3] About 17–23 cases of pneumothorax occur per 100,000 people per year.[3][5] They are more common in men than women.[3]