NUR 3125 Lecture Notes - Lecture 10: Mean Arterial Pressure, Left Coronary Artery, Heart Valve
Document Summary
Cardiac output = hr x stroke volume [preload (volume), contractility, Hr must be within normal limits because ventricles needs time to fill. Deliver oxygen, nutrients and other substances to body tissues. Intrinsic regulators of cardiac function: endocrine, nervous system. Elastic: aorta, pulmonary trunk, allows for stretch during cardiac ejection. Muscular: peripheral, distribution of blood flow, vasoconstriction, vasodilation. Contraction of skeletal muscle helps promote venous return to heart. Cells can adjust arrangement and number to meet local requirements. Allows for: remodeling, tissue growth, repair, atherogenesis, fibrinolysis. Contraction : decreased size of lumen, vasoconstriction, increased resistance, increased blood pressure, increased cardiac work. Relaxation: increased size of lumen, vasodilation, decreased resistance, decreased blood pressure, decreased cardiac work. Precapillary sphincter regulates blood flow through the capillary: maintain arterial pressure in capillary beds. Allow for exchange of gas, nutrients and waste. Definition: amount of blood moved per unit of time, liters or ml per minute. Regulation: pressure, resistance, velocity, turbulent vs laminar flow, compliance.
