When applying topical anesthetics, the dirt and dust on the patient’s skin surface should be thoroughly removed and cleaned, which is more conducive to the absorption of local topical anesthetics. At the same time, a light local disinfection of iodophor, disinfection after the external anesthetic can be laid flat on the skin surface mucosa, after about 20 minutes after the onset of action can be completely removed from the surface of the applied cream. At the same time, it is possible to take preoperative preparations before surgery to disinfect and lay the surgical aperture, etc. The problem of attention is that in the application of external anesthetic, must avoid eating spicy, irritating food, try to drink less alcohol. If the case of drinking alcohol is easy to accelerate the blood circulation on the surface of the skin, easy to make the external anesthetic failure, the effect time is relatively short, these are the more common methods.