If the needle is left in the patient’s vein, it may be normal to feel vague pain because the needle is left in the patient’s vein, which is after all a foreign body, so it is normal to have vague local pain or swelling, and the patient is not advised to worry too much. However, if the patient has an indwelling needle, he or she must pay attention to the activities of the affected limb and avoid extensive and strenuous activities, which may cause the indwelling needle to fall off or bleed back, causing the indwelling needle to become blocked. The indwelling needle is a kind of flowing injection needle commonly used in hospitals nowadays, which can relieve the pain of the patient to lance the needle again for infusion, but it may bring inconvenience to the patient’s life, so effective care of the indwelling needle must be carried out to avoid needle dislodgement and blockage.