Based on the patient’s medical history, physical examination and ultrasound of the chest and abdomen, CT of the chest and abdomen, ultrasound of the heart, and a variety of blood tests, we should clarify the cause of chest and abdominal fluid, whether it is caused by heart disease, liver disease, or kidney disease, and make a clear diagnosis before taking the next step. If the patient is suffering from thoracoabdominal fluid caused by the heart, cardioplegia, diuresis and potassium supplementation can be given, which must be guided by a professional physician. If the thoracic ascites is caused by the liver, protein supplementation and liver-protective treatment can be given, after the treatment opinion of a doctor in gastroenterology or hepatology, and if it is caused by nephrotic syndrome, hormone treatment can be applied, using the treatment plan of nephrology. It may also be malignant pleural fluid caused by thoracoabdominal tumor.