The purpose of tube flushing is to keep the tubes open and prevent obstruction of the tubes due to blood, food residue, or foreign objects in the abdominal cavity. For example, during infusion, the arm will be injected with an intravenous indwelling needle, and before using the indwelling needle, the tube needs to be flushed with saline to prevent blood from coagulating inside the needle, which will affect the intravenous input, and the tube needs to be sealed with heparin after the end of the infusion to prevent blood from coagulating inside the needle and forming an obstruction. Gastric tubes, as well as enteral nutrition tubes within the gastrointestinal tract, also need to be flushed prior to use; sometimes enteral nutrition fluids form clots within the tubes, causing them to become inaccessible. After a long period of time, due to the necrotic tissue inside the abdominal cavity, the drainage tube will be blocked, poor drainage and other phenomena, if necessary, also need to use saline to flush the tube.