Perfusion and Renal Elimination
VI: Glossary
Afterload: The tension that the ventricles must develop to pump blood effectively against the resistance in the vascular system.
Anticoagulant: Any substance that opposes coagulation.
Arrhythmia: A deviation from the normal pattern of impulse conduction and contraction of the heart, which, if serious and untreated, can lead to decreased cardiac output and death.
Arteriosclerosis: A condition when compliance in an artery is reduced, and pressure and resistance within the vessel increase. This is a leading cause of hypertension and coronary heart disease, as it causes the heart to work harder to generate a pressure great enough to overcome the resistance.
Artery: A blood vessel that carries blood away from the heart (except for pulmonary arteries that carry oxygenated blood from the lungs back to the heart).
Atherosclerosis: A buildup, called plaque, that can narrow arteries enough to impair blood flow.
Blood pressure: A type of hydrostatic pressure, or the force exerted by blood on the walls of the blood vessels or the chambers of the heart.
Capillaries: Smallest arteries where nutrients and wastes are exchanged at the cellular level.
Cardiac Output (CO): To calculate this value, multiply stroke volume (SV), the amount of blood pumped by each ventricle, by heart rate (HR), in contractions per minute (or beats per minute, bpm). It can be represented mathematically by the following equation: CO = HR × SV.
Cerebrovascular Accident (CVA): Lack of blood flow to the brain that can cause irreversible brain damage, often referred to as a “stroke.”
Coagulation: The formation of a blood clot.
Compliance: The ability of any compartment to expand to accommodate increased content. The greater the compliance of an artery, the more effectively it is able to expand to accommodate surges in blood flow without increased resistance or blood pressure. Veins are more compliant than arteries and can expand to hold more blood. When vascular disease causes stiffening of arteries, compliance is reduced and resistance to blood flow is increased.
Contractility: The force of contraction of the heart.
Diastole: The period of relaxation that occurs as the chambers fill with blood.
Edema: The presence of excess tissue fluid around the cells.
Embolus: When a portion of a thrombus breaks free from the vessel wall and enters the circulation. An embolus that is carried through the bloodstream can be large enough to block a vessel critical to a major organ. When it becomes trapped, an embolus is called an embolism. In the heart, brain, or lungs, an embolism may accordingly cause a heart attack, a stroke, or a pulmonary embolism.
Fibrillation: An uncoordinated beating of the heart, which, if serious and untreated, can lead to decreased cardiac output and death.
Fibrinolysis: The gradual degradation of a clot.
Hemostasis: The process by which the body temporarily seals a ruptured blood vessel and prevents further loss of blood.
Hyperlipidem