Venous return: The process of systemic venous tube blood flow back to the right atrium, systemic venous system of blood volume is very large, accounting for more than half of the total blood, veins easy to expand, but also can contract, so it plays the role of blood storage inventory. So what are the factors that affect venous return? The following Xiaomai will summarize for you:
(1) The driving force of venous return is the pressure difference at both ends of the vein, that is, the difference between peripheral venous pressure and central venous pressure. The formation of the pressure difference mainly depends on the contractile force of the heart, but it is also affected by respiratory movement, body position, muscle contraction, etc.
(2) Skeletal muscle compression acts as a muscle pump to promote venous return
(3) Respiratory movement affects venous return by affecting intrathoracic pressure.
(4) When the human body changes from lying position to standing position, the amount of blood returned to the heart is reduced.