Blood circulation is the movement of blood through the heart and the vascular system in a certain direction by the action of the heart pump. The blood circulation consists of the body circulation as well as the pulmonary circulation, which are interconnected by the heart and complete a whole circulatory system, where the body circulation is mainly responsible for bringing oxygen and nutrients to the various tissues and organs of the body, while the pulmonary circulation is mainly responsible for metabolizing carbon dioxide to the outside of the body and bringing oxygen to the body. The blood circulation consists of the main pump, the heart, and the arteries and veins. Its main clinical significance is to ensure the metabolism of various tissues and organs of the body, which obtain nutrients and oxygen from the blood and use these substances to produce energy to ensure the normal function of the body.