Cardiac output: venous circulation regulates cardiac output
To evaluate the effect of the peripheral circulatory system, we first removed the heart and lungs in experimental animals and replaced them with an artificial cardiopulmonary support system.
The factors that regulate cardiac output above are quite adequate in most common cases. However, to further elucidate cardiac regulation in stressful situations, such as heavy physical activity, heart failure, and circulatory failure, discuss the following.
In quantitative methods, we need to clarify the following two basic factors: in the regulation of cardiac output: (1) the pumping capacity of the heart, represented by the cardiac output curve (2) the factors Peripheral factors affect the return of blood to the heart, represented by the venous circulation curve. Then, combine the two curves by the same quantification to see the relationship between cardiac output, venous circulation, and right atrial pressure at the same time.
The entire peripheral circulatory system should be considered when evaluating factors that regulate cardiac output.
To evaluate the effect of the peripheral circulatory system, we first removed the heart and lungs in experimental animals and replaced them with an artificial cardiopulmonary support system. Then, other factors, such as blood volume, vascular resistance, and central venous pressure, were changed to assess the effect on circulation.
This study confirmed 3 important factors related to venous circulation drawing blood from the peripheral circulatory system:
1. Right atrial pressure: pressure that obstructs blood from the vein to the right atrium -
2. Vascular filling pressure (measured by mean vascular filling pressure) helps return blood to the heart (this pressure can be measured anywhere on the peripheral vascular system when blood flow stops) and will be described in more detail below).
3. Resistance to blood flow: in peripheral vessels and right atrium.
The above factors will be described through the venous circulation curve.