How can I pat my child’s back to promote coughing up sputum after surgery?

　　After surgery, children may have more or less coughing and coughing up phlegm, so it is important to strengthen physical therapy after surgery and pay attention to patting the back to promote the child’s phlegm discharge. When patting the back, you should drum your palm in the shape of a sunken spoon, and pat the child’s back with the surface of your palm, from bottom to top, with moderate strength, not too gently, too gently will not work. The child is not badly patted, but the phlegm is likely to suffocate the child.