PSL201Y1 Lecture 16: PSL201 Week 16 Reading Notes
Document Summary
Psl201 lecture 16 reading notes; cardiovascular physiology 6. Blood pressure is determined by cardiac and vascular effectors. Blood pressure (mmhg)= cardiac output (l/min) x peripheral resistance (mmhg*min/l) Blood pressure: average aortic pressure during the cardiac cycle. Cardiac output: blood flow out of the heart. Peripheral resistance: how difficult it is for blood to flow through the body. Mean arterial pressure (map) is determined by cardiac output and resistance. Any decline in map compromises blood flow to all the systemic organs. Map rises following an increase in heart rate or stroke volume (which tends to increase co) and tpr. Increase in co: with tpr remaining constant, blood flows into the aorta faster than it flows out. So the blood volume within the aorta increases and vessels expand. Expansion of the aorta stretches the wall of the aorta causing it to exert a large inward force on the blood so that the pressure rises.
