First aid measures for pneumothorax must be determined by the specific type of pneumothorax. In case of tension pneumothorax with progressive dyspnea, a long syringe needle can be used to puncture into the pleural cavity at the midclavicular line between 2 and 3 ribs in the upper chest to expel the gas and relieve the symptoms. In case of common spontaneous pneumothorax or pneumothorax caused by trauma without progressive dyspnea, closed drainage of the chest cavity can usually be performed by cutting the skin at the midline of the clavicle between 2-3 ribs in the upper chest, placing a tube and then connecting a water seal bottle, usually the gas inside the chest cavity is discharged through the tube into the water seal bottle, thus gradually healing the lung wound.