Subcutaneous emphysema is usually secondary to traumatic pneumothorax or spontaneous pneumothorax, which is caused by the rupture of the wall pleura and gas infiltration into the subcutaneous tissue, and a distinct sensation of griping snow or twisting hair will be perceived during physical examination. In the case of tension pneumothorax secondary to subcutaneous emphysema, the patient will have significant respiratory distress, and in severe cases, mediastinal oscillation will also occur, in which case closed chest drainage surgery should be performed promptly. In patients with subcutaneous emphysema or combined mediastinal emphysema, breathing is also affected, manifesting as restricted or difficult respiration. An incision may be made in the suprasternal fossa and the subcutaneous tissue may be separated to facilitate the removal of the pneumothorax. Anti-infection therapy should also be actively administered, and if the patient has significant pain, appropriate pain medication can be given, such as diazoxide or lysergic acid intramuscular injection.