Modeling Cerebral Blood Flow Control During Posture Change from Sitting to Standing

Hypertension, decreased cerebral blood flow, and diminished cerebral blood flow velocity regulation, are among the first signs indicating the presence of cerebral vascular disease. In this paper, we will present a mathematical model that can predict blood flow and pressure during posture change from sitting to standing. The mathematical model uses a compartmental approach to describe pulsatile blood flow velocity and pressure in a number of compartments representing the systemic circulation. Our model includes compartments representing the trunk and upper extremities, the lower extremities, the brain, and the heart. We use physiologically based control mechanisms to describe the regulation of cerebral blood flow velocity and arterial pressure in response to orthostatic hypotension resulting from postural change. To justify the fidelity of our mathematical model and control mechanisms development, we will show validation results of our model against experimental data from a young subject.