Edema can generally be divided into three levels. At the first level, the local swelling is mild and feels as soft as the lips when pressed on. In this case, no special treatment is needed for the swelling and it is recommended to elevate the affected limb appropriately. At the second level, the local swelling is hard and can feel like the hardness of the nose when pressed. The affected limb needs to be braked and elevated above the heart to speed up blood return, and symptomatic treatment, such as the application of sodium heptaerythrartoside or mannitol, must be applied to reduce swelling. At the third level, the local swelling is more serious, when the local hardness will reach the same hardness as the forehead, it is recommended that timely surgery must be performed to cut the local skin and decompress to avoid causing local neurovascular pressure, which can lead to injury.