Pneumothorax is a common medical emergency, the severity of which is related to the rapidity of onset, the degree of lung compression, the primary disease, and the type of pneumothorax. In mild cases, conservative treatment can provide significant relief, while in severe cases, respiratory function can be seriously affected. Pneumothorax is caused by various causes of rupture of the pleura and the entry of air into the pleural cavity. Patients with closed pneumothorax are usually not serious if they have their first attack and have no primary disease, and the degree of lung tissue compression is mild, and conservative treatment can provide significant relief. In contrast, if it is a recurrence, with heavy lung compression, or combined with multiple primary diseases, such as asthma, pulmonary fibrosis, coronary artery disease, etc., it is relatively serious and may seriously affect lung function if left untreated. As for open pneumothorax and tension pneumothorax, the respiratory distress is often relatively serious and therefore needs to be treated as soon as possible, especially for patients with tension pneumothorax, which may even be life-threatening if not treated in time. Usually, if the lung compression is less than 30%, high concentration oxygen inhalation, bed rest and conservative treatment can make the patient gradually absorb the gas in the chest cavity. If the lung compression is more than 30%, treatment such as thoracentesis is often required to extract the gas in time to restore the patient’s respiratory function.