After the pleural effusion is reduced, the main manifestation is the reduction of the previous compression symptoms, mainly including the reduction of chest tightness, the reduction of respiratory restriction symptoms and the reduction of abnormal heart condition symptoms. 1. Reduction of chest tightness: pleural effusion compresses the lungs and causes a feeling of tightness and swelling in the chest, which will be alleviated after the reduction of pleural effusion. 2. Reduction of respiratory restriction: the compression caused by pleural effusion will cause respiratory restriction, resulting in increased respiratory rate and shallow respiration, and after the reduction of the effusion, the corresponding symptoms will be reduced. 3. Abnormal heart condition: Because abnormal breathing condition will cause hypoxia symptoms, resulting in increased heart rate, after the pleural effusion is reduced, the corresponding abnormal heart condition will also be reduced. The specific condition of pleural effusion needs to be reviewed regularly in conjunction with CT examination, and standardized treatment should be carried out under the guidance of clinicians. Once the pleural effusion recurs, the patient should be hospitalized.