McMurdo surgery is a common minimally invasive procedure on the breast with a relatively small incision that can easily cause a hematoma if bleeding does have difficulty flowing out of the incision. Hematomas after breast McMurdo surgery are more common, but not particularly frequent. It has specific manifestations, such as hard nodules or subcutaneous bruising near the surgical incision, in the area of the residual cavity, for example, you may see purple or yellow petechiae on the nearby skin or very swollen and painful breasts. When there is localized skin pain and an increase in skin temperature, it may be a hematoma accompanied by infection. If any of these conditions occur, you should contact your doctor immediately for treatment, or you may have an ultrasound to confirm the presence of a hematoma.