The operation steps and process of infusion with indwelling needle mainly include selecting vein, sterilizing, puncturing, fixing and adjusting drip rate. 1. Selection of vein: choose a thick, straight, elastic vein with rich blood flow, avoiding joints. 2. Disinfection: routinely disinfect the skin (6~8cm in diameter), tie a tourniquet 8~10cm above the puncture site and ask the patient to make a fist. 3. Puncture: select the type of indwelling needle according to the patient, connect it with the infusion set, expel the air inside the indwelling needle, remove the needle sleeve, rotate the outer sleeve, tense the skin of the puncture site with one hand, hold the needle wing with one hand, enter the needle with the needle tip beveled to face upward and the skin at an angle of 15°~30°, see the return of blood and then lower the angle, continue to advance the needle flatly, hold the Y connector with the left hand, withdraw the needle core with the right hand for about 0.5cm, and then send the core and outer sleeve into the vein together with the needle seat, and send the core and outer sleeve into the vein together. The needle holder sends the needle core and the outer sleeve into the vein together, withdraws the needle core completely, loosens the tourniquet and opens the regulator. 4. Fixation: Fix the needle handle with the infusion patch, then fix the puncture point with the transparent dressing, and finally fix the hose with the infusion patch. 5. Adjust the drip rate: adjust the appropriate drip rate according to the patient, and tell the patient not to mobilize at will. Attention should be paid to waterproof, keep the dressing clean and dry, if the dressing is loose or wet or other discomforts, the nurse should be told to change it in time, if there is discomfort, the doctor should be contacted in time to deal with it.