After deep vein puncture placement, it needs to be fixed with a sterile gauze patch to prevent its distortion and displacement, and the puncture site should be observed for blood leakage, exudate or inflammatory reaction. The puncture site needs to be disinfected and the dressing changed daily. The access after each rehydration needs to be sealed with heparin to prevent the formation of thrombus. Each time it is used, it should be observed whether the fluid drip is smooth, whether the catheter is twisted and deformed, and whether the depth of the catheter is dislodged. The aseptic operation should be strictly observed during infusion, and the heparin cap and tee interface also need to be routinely disinfected to prevent contamination. The internal jugular vein and subclavian vein should be left in place for about 15 days, and the longest time should not exceed one month, and the femoral vein has a higher chance of contamination, which should not exceed 3 days in general. To remove the deep vein catheter, the patient is placed in a supine position, and after routine disinfection, the sutures are removed with sterile instruments, and after pressing the puncture site with sterile gauze, the catheter is slowly removed, checked for integrity, and the puncture site is pressed for about 10-15 minutes and covered with sterile dressing. Special attention needs to be paid to the need for the patient to adopt a proper position, to properly withdraw the catheter to prevent air embolism, and to observe from time to time for 24 hours for blood and fluid leakage.