Simulation of the human cardiovascular system: a model with normal responses to change of posture, blood loss, transfusion, and autonomic blockade

The model of the human circulation here used consists of the minimum number of compartments required to simulate the distribution and flow of blood under different conditions. In the model the peripheral circulation consists of four parallel vascular compart ments, each with a typical inflow resistance and compliance. Each of the peripheral compartments is in equilibrium with an interstitial fluid compartment. Blood returning from the peripheral circulation flows into the great veins and pulmonary vessels, from which it is pumped by the heart into the high-pressure aorta and arteries. The distribution and flow of blood are regulated by the autonomic nervous system, which receives inputs from arterial pressure and pulmonary blood volume, and which controls cardiac output and the resistance and compliance of each peripheral vascular compartment.