We often encounter patients who have sprained ankles, but after applying hot compresses, the ankle becomes more and more swollen and painful, while after applying cold compresses, the ankle becomes less and less swollen and painful. How to choose “hot” or “cold”? The main function of cold compress: 1, reduce the metabolic rate and nerve conduction speed, relieve pain; 2, contract capillaries to achieve the purpose of hemostasis; 3, anti-inflammatory, reduce local inflammatory reaction; 4, cooling, reduce local inflammatory injury. Second, how to correctly cold compress: 1, for acute trauma or subacute injury, within 48 hours after the injury, this time the bleeding basically stopped, cold treatment of the wound is the best time; 2, for acute injuries, the use of cold treatment time is about 15 to 20 minutes, each time to be 1-2 hours apart, in order to control the temperature of the ice compress recommended outside can be wrapped thin towel to the surface temperature is slightly lower. This is because if the continued ice will lead to the possibility of frostbite. Cold compress contraindications: 1, extremely sensitive to cold stimulation, cold compress may promote arterial spasm; 2, the elderly arterial insufficiency to be used with caution, may aggravate the ischemia; 3, the neural tissue paralysis is absolutely prohibited, because they can not feel hot and cold, so it is easy to frostbite; 4, cold compress and ice massage should not be used for rheumatoid arthritis, Raynaud’s syndrome, sensory damage to the region. Hot compress a. The main role of hot compress: 1, relieve pain; 2, relieve stiffness; 3, reduce muscle spasm; 4, relax the tension of muscles and joints; 5, so that soft tissue to restore normal flexibility; 6, increase the blood supply to the injury site, promote blood circulation, conducive to healing. Second, how to correctly apply heat: 1, hot compress treatment should be used mainly for acute injuries in the late stages and chronic injuries. Acute injury late refers to the injury 48 hours later, because this time often bleeding stops. Chronic injury usually occurs after a longer period of injury (repeated overuse as well as strain), not a sudden accidental injury. 2, in the home, the most simple and easy to obtain is a hot towel, warm bath. But its heat can generally only last 5-10 minutes, the use of time is insufficient. Of course hot towels in the microwave oven is also simple and easy to heat. 3, the effect of wet compress is generally better than dry compress, because the tissue permeability is good, can reach the deeper tissue. Usually a hot compress for about 30 minutes, the temperature control at 40-50 ℃, 2-3 times a day, according to medical advice to adjust the time of hot compress. Third, the contraindications of hot compress: 1, skin sensory abnormalities, such as diabetic foot patients (if the temperature is too high may not feel); 2, hot compress too long or the temperature is too hot, prone to thermal burns; 3, a history of thermal skin allergies; 4, peripheral vascular disease, circulatory system disorders (cardiovascular patients, may induce acute illness); 5, acute trauma period use will be hot compress aggravate the degree of swelling; 6, deep vein thrombosis 7, infection; 8, malignant tumors, etc. Note: 1, not all chronic injuries are to use heat, such as belonging to the acute attack is still the first choice to use ice; 2, not all acute injuries are to use ice, early swelling, pain control can be changed to heat; 3, the choice of ice and hot compress according to the situation, preferably under the guidance of a doctor or rehabilitation physician.