Bruising after surgery is mainly due to surgical destruction of capillaries, resulting in subcutaneous bleeding and the formation of blood clots, blood clots oxidized, the color change, in the appearance of the formation of cyan, so called bruising. For postoperative bruising, it is recommended to apply cold compresses immediately, intermittent cold compresses within 48 hours, do not sustained cold compresses, after 48 hours can be hot compresses, because this time the vascular hot compresses can make blood vessels dilated, increase the absorption of oozing around the bruise, and at this time also to avoid scalding the skin. You can also paste potato chips, because potatoes are rich in starch, with hypertonic effect, can use the concentration difference to make the tissue water loss, thus relieving local swelling. Skin bruises can be how long to disappear depends on the individual, if the active treatment is appropriate, generally 3-5 days can disappear, if the area is larger, more, it may take 2 weeks to gradually absorb, so it depends on the way the operation and the size of the operation, as well as the postoperative traumatic area to decide. Surgery large may bruise slow absorption, the scope of surgery smaller bruise, if timely treatment, absorption is faster. So it should be treated aggressively. Cold compresses in the early stage and hot compresses after 48 hours will promote its absorption.