EHS 385 Lecture Notes - Lecture 23: Mean Arterial Pressure, Exercise Physiology, Hemorheology
2 Jan 2019
School
Department
Course
Professor
Document Summary
Blood flow: directly proportional to pressure difference b/w 2 ends of system. Inversely proportional to resistance: blood flow = pressure difference/resistance. Pressure: proportional to diff b/w mean arterial pressure and right atrial pressure. Increased diff b/w 2 ends of system = increased blood flow. Decreased dif b/w 2 ends of system = decreased blood flow. Resistance to blood flow depends on: radius of blood vessel = greatest influence on resistance, length of blood vessel, blood viscosity. Increase/decrease length of blood vessel = increase/decrease resistance. Increase/decrease radius of blood vessel = increase/decrease resistance. Mean arterial pressure high in large arteries: decreases as blood flows through systemic circulation to large veins where pressure low, largest drop in bp happens across arterioles. Arterioles have great vascular resistance to bp: aka resistance vessels. O2 demand by skeletal muscles while exercising is 15 -25 times greater than rest. Increased cardiac output: redistribute blood from inactive organs to active skeletal muscle.
