The concept of intravenous therapy is a method of introducing various drugs, which also includes blood products as well as blood, into the blood circulation through veins, and the main methods include intravenous injection, intravenous infusion and intravenous blood transfusion, and the tools commonly used in intravenous therapy include a series of tools such as syringes, infusion sets, transfusion sets, peripheral indwelling needles, central venous catheters, and infusion ports. When intravenous infusion we must pay attention to the protection of blood vessels, repeated stimulation of blood vessels can easily cause thrombophlebitis, but also to carry out the maintenance of the quality of infusion products, try to avoid infection. Infusion products once infected can easily lead to bacteremia, thus endangering life. The infusion process should also be careful not to enter air into the blood, and should also pay attention to the damage to the blood vessels from the infusion of some irritating drugs.