A history of left-sided pneumothorax episodes and reoccurrence of a right-sided pneumothorax is not a recurrence, but in some patients the right-sided pneumothorax may have the same etiology as the left-sided pneumothorax. Common classifications of pneumothorax are based on the mode of attack, including closed pneumothorax, open pneumothorax, and tension pneumothorax. The main clinical manifestations of pneumothorax are chest tightness, severe dyspnea and even circulatory disturbances, which are common in patients with tension pneumothorax. For patients with a history of left-sided pneumothorax, reoccurrence of right-sided pneumothorax is not a recurrence. In general, some patients with unilateral pneumothorax are prone to recurrence, such as spontaneous pneumothorax in closed pneumothorax and pneumothorax caused by chronic obstructive pulmonary disease, which is prone to recurrence of pneumothorax on one side.