Bleeding is, as the name suggests, bleeding when a blood vessel ruptures and blood flows outside the vessel. The causes of bleeding are different for different parts of the body and different diseases. For example, bleeding caused by trauma, such as a broken head or fracture, or bleeding caused by a rupture in a certain part of the arm, are all caused by bleeding due to rupture of blood vessels as a result of traumatic wounds. If the bleeding is caused by tumor, generally speaking, it is caused when the tumor grows to a large size, and the blood supply of the tumor is not able to be completely supplied, leading to the rupture of the tumor surface, resulting in the rupture of blood vessels and causing bleeding. If the bleeding is caused after surgery, it is mostly due to the oozing of blood from the surgical wound or the dislodging of the ligature wire during the surgery.