The vascular bed is composed of capillary blood, tiny arteries, and tiny veins. The blood volume in the vascular bed, called the vascular bed volume, is an important part of the body’s blood volume, accounting for a larger proportion and significance. The vascular bed is the part of the body where nutrients and metabolites are exchanged, and at the same time, the vascular bed of the body plays the role of regulating the blood pressure of the body. The vascular bed can regulate the body’s circulating blood volume by adjusting the volume of the vascular bed to produce a corresponding change in blood pressure and maintain it in a certain normal range. When the vascular bed is contracted, the effective circulating blood volume of the body rises and blood pressure gets increased, while when the vascular bed is diastolic, the effective circulating blood volume of the body decreases, causing blood pressure to lower. Therefore, changes in the volume of the vascular bed will have a corresponding effect on the blood pressure of the body.