There are corresponding indications and contraindications for thoracic cavity. There are two major indications: First, diagnostic puncture to extract pleural effusion, clarify the nature of pleural effusion and diagnose the disease. Second, therapeutic, massive hemopneumothorax, abscess chest can be punctured to extract fluid and gas to improve the symptoms of compression. For certain patients with malignant tumors, intrapleural perfusion chemotherapy and anti-tumor therapy can be performed. In the presence of recurrent spontaneous pneumothorax and malignant pleural effusion, a certain drug can be injected into the chest cavity to promote healing and reduce recurrence. There are two main contraindications: First, there are coagulation disorders and hematological diseases. This type of patients cannot be punctured because there is a possibility that the intercostal vessels will be damaged during the puncture process, which will cause a lot of bleeding, because there is a disorder in the coagulation mechanism and the blood cannot self-clot, there will be a lot of blood in the chest cavity and the surgery cannot be performed to stop the bleeding, so it brings a lot of trouble. Second, puncture site infection or puncture site tumor, trauma, etc., can not be punctured, which will cause the spread of inflammation or tumor implantation and metastasis, the loss is not worth the gain, so puncture should not be performed.