Many parents of febrile children often get a response when they visit the clinic that the body temperature is below 38.5°C and go home for physical cooling, but many clinicians cannot give an accurate answer on how to scientifically perform physical cooling. So, what is the scientific physical cooling for a febrile child? Physical cooling is the local or systemic use of low temperature conduction and evaporation to bring down the body temperature. Normal pediatric body temperature is shown in the table below, and any temperature above the normal range is called fever. There are many factors affecting the body temperature, the common ones are eating (especially for infants and young children), movement, crying, too thick clothing, high ambient temperature can lead to an increase in body temperature; while hunger, less movement, poor warmth can lead to a decrease in body temperature. Physical cooling mainly includes two major methods, namely local cold compresses and systemic cold therapy. 1, local cold compresses commonly used ice bags, and ice capsules, the principle of contact conduction to achieve cooling purposes. The site of placement is often the child’s forehead or head, the ice capsule can be placed on the child’s body surface distribution of large blood vessels, such as the neck, axilla, groin, etc., pay attention to the child’s local skin color, such as pale, cyanosis and other conditions should immediately stop using cold to prevent impaired blood circulation or frostbite. 30 minutes later to measure the temperature and record, the need for a long time with cold should rest for an hour before repeated use, to give the local tissue The time for recovery. Many parents of children often ask if they can put fever patches on the palms and feet, but this method of fever reduction is wrong. When a child has a fever, the peripheral circulation is poor, resulting in “hot body, cold hands and feet, shivering and discomfort”. Therefore, it is not possible to apply cold compresses to the palms and feet when you have a fever. 2, warm water swabbing bath warm water swabbing bath is a common way of whole body cold therapy, the principle of warm water contact with the skin, through evaporation, conduction to increase the body heat dissipation, to achieve cooling purposes. Usually the basin can hold 32-34 ℃ warm water, swabbing bath before the ice bag placed on the head, to prevent swabbing bath epidermal vasoconstriction, head congestion, aggravating headache. The hot water bag is placed on the bottom of the feet to avoid chills and discomfort. Loosen the end of the bed and the cover without exposing too much, remove the clothes and lay the bath towel under the body. Wring a small soaked towel until it is half dry, wrap it around the operator’s hand and pat in a centrifugal direction. Pat the upper limbs, lower limbs, back, each side of the limbs or back swabbing time of 3 minutes, the whole process does not exceed 20 minutes. The axillae and groin are where the large blood vessels pass through, so the swabbing time should be extended. It is forbidden to swab the anterior chest area, the abdomen, the back of the neck, the heart of the feet and other parts of the body to avoid adverse reactions. After swabbing, dry the skin with a large towel, remove the hot water bag, assist the child to take a comfortable position, and retest the body temperature after half an hour. If the body temperature drops below 39℃, remove the ice bag from the head. In addition to the above two methods, drinking sugar saline for several times can better replenish the unobtrusive water loss due to fever and better facilitate the recovery of body temperature.