NURS 3220 Lecture Notes - Lecture 16: Hyperglycemia, Inotrope, Doxazosin
Document Summary
Arteries: transport blood under pressure from heart to tissues. Arterioles: act as control valves- regulate local blood flow/bp. Capillaries: sites for exchange (fluid, o2, co2, nutrients, hormones, wastes) Veins: transport blood back to heart, and act as a reservoir for blood: dilate easily, distend, decrease co/pre-load. Sv= myocardial contractility (how effective heart muscle is pumping) Afterload resistance (force the lv must work against) So : to alter bp we must alter one or more of the above. Vena cave (no valves, equal pressure) ra tricuspid valve rv pulmonary arteries pulmonary circulation, picks up o2, release co2 pulmonary veins la lv aorta. Myocardial contractility: determined by: the degree of cardiac dilation (preload, increased by: sns stimulation of beta-adrenergic receptors in the myocardium. Preload: the amount of tension (stretch) applied to a muscle before contraction, dependent on the force of venous return. Pump system, pumping of arteries, contraction of skeletal muscle: end-diastolic volume, or end-diastolic pressure.
