Children with preoperative pneumonia or combined airway stenosis are prone to sputum after surgery, so postoperative care should be taken to: 1. Avoid prolonged lying of the child, turn the child more often, and hold the child standing up more often. 2. Pat the back: pat the child’s back in the morning, at night before going to bed and when the child coughs. Pat the child’s back with an empty hand and pat from the bottom to the top on both sides of the back. 3.Oral medicine: Western medicine: Mucosolvan syrup, Chinese medicine: compound fresh bamboo leech oral medicine 4.If available, you can also nebulize inhalation. (Need nebulizer)