Ice is a widely used clinical treatment method. The application of ice is mainly in the following areas, for trauma, sprains, local bruising and swelling, ice should be applied within 24 hours. Because ice can make local vasoconstriction, reduce bleeding, and provide a good guarantee for the absorption of local bruises later. Ice can also numb the nerves to reduce pain and relieve the patient’s suffering. In addition, ice can be used for physical cooling in patients with high fever, which can quickly bring down the body temperature and make the disease improve. For serious patients such as traumatic brain injury, when high fever convulsions occur, ice can be a good way to cool down and eliminate muscle tension, so that the patient can temporarily return to normal.