NUR 2048 Exam 1 correctly answered
(graded A+)
define perfusion
the flow of blood through the arteries and capillaries delivering nutrients and oxygen to the cells
define central perfusion
the force of blood movement that is generated by cardiac output
define systole
contraction of ventricles
define diastole
resting or relaxation of the heart
define ejection fraction
measurement of blood leaving the left ventricle each time it contracts
what is the normal ejection fraction rate?
50-70%
,what four factors determine cardiac output
HR
Contractility
Blood volume
Venous return
how do you calculate cardiac output?
heart rate x stroke volume
what factors make up the stroke volume?
preload, afterload, contractility
define preload
volume of blood in ventricles at end of diastole
what two factors influence preload?
volume and contractility
define afterload
force against which the heart must pump
what factors reduce cardiac output (central perfusion)?
-altered myocardial contraction
,-changes in myocardial conduction
-ineffective heart valves
what are the consequences of impaired central perfusion?
-slow blood flow
-MI risk
-shock
define tissue perfusion
blood flow through arteries and capillaries to target tissues
what does it mean in the tissue perfusion is impaired?
the tissues have reduced blood flow which decreases delivery of oxygen and nutrients to those tissues
what complications could occur from impaired tissue perfusion?
-thrombi in the veins
-MI
-vasoconstriction
-stroke
-blood loss
-hemorrhage
-cardiac arrest
describe the blood flow through the heart
, Blood enters the heart via inferior and superior vena cava and dumps into right atrium. Blood then
travels through the tricuspid valve into the right ventricle. After that blood continues up through the
pulmonary or semi lunar valve, and out the pulmonary arteries into the lungs. The pulmonary veins then
retrieve blood and continue flow into the left atrium. Following that blood flows through the bicuspid or
mitral valve to the Left ventricle. Blood then continues up through the aortic semilunar valve and into
the aorta.
sa node inherent rate
60-100 bpm
av node inherent rate
40-60 bpm
ventricles (bundle of his) inherent rate
20-40 bpm
describe automaticity
the property of the cardiac cells to generate electrical impulses
where does the impulse normally come from?
sa node
when do disturbances in conduction occur?
when conduction is too rapid, slow, or when it is blocked this causes the impulse to travel the wrong way
(graded A+)
define perfusion
the flow of blood through the arteries and capillaries delivering nutrients and oxygen to the cells
define central perfusion
the force of blood movement that is generated by cardiac output
define systole
contraction of ventricles
define diastole
resting or relaxation of the heart
define ejection fraction
measurement of blood leaving the left ventricle each time it contracts
what is the normal ejection fraction rate?
50-70%
,what four factors determine cardiac output
HR
Contractility
Blood volume
Venous return
how do you calculate cardiac output?
heart rate x stroke volume
what factors make up the stroke volume?
preload, afterload, contractility
define preload
volume of blood in ventricles at end of diastole
what two factors influence preload?
volume and contractility
define afterload
force against which the heart must pump
what factors reduce cardiac output (central perfusion)?
-altered myocardial contraction
,-changes in myocardial conduction
-ineffective heart valves
what are the consequences of impaired central perfusion?
-slow blood flow
-MI risk
-shock
define tissue perfusion
blood flow through arteries and capillaries to target tissues
what does it mean in the tissue perfusion is impaired?
the tissues have reduced blood flow which decreases delivery of oxygen and nutrients to those tissues
what complications could occur from impaired tissue perfusion?
-thrombi in the veins
-MI
-vasoconstriction
-stroke
-blood loss
-hemorrhage
-cardiac arrest
describe the blood flow through the heart
, Blood enters the heart via inferior and superior vena cava and dumps into right atrium. Blood then
travels through the tricuspid valve into the right ventricle. After that blood continues up through the
pulmonary or semi lunar valve, and out the pulmonary arteries into the lungs. The pulmonary veins then
retrieve blood and continue flow into the left atrium. Following that blood flows through the bicuspid or
mitral valve to the Left ventricle. Blood then continues up through the aortic semilunar valve and into
the aorta.
sa node inherent rate
60-100 bpm
av node inherent rate
40-60 bpm
ventricles (bundle of his) inherent rate
20-40 bpm
describe automaticity
the property of the cardiac cells to generate electrical impulses
where does the impulse normally come from?
sa node
when do disturbances in conduction occur?
when conduction is too rapid, slow, or when it is blocked this causes the impulse to travel the wrong way
