Cardiac output and venous return Flashcards
What are the 3 definitions or caridac output?
- quantity of blood pumped into the aorta each minute by the heart
- quantity of blood that flows through the circulation
- sum of all the blood flows to all of the tissues of the body
How would you define cardiac index?
Cardiac output per square meter of body surface
What is the relationship between cardiac index and age?
Cardiac index peaks around 10 yrs and begins to decline as one ages
What is the relationship between cardiac output, cardic index, and oxygen consumption during exercise?
They all increase relative to the amount of work/exercise you are doing
Why would you uses the Fick principle of blood flow?
To calculate blood flow through an organ.
According to the Fick principle of blood flow, what equation would you use to calculate cardiac output?
Cardiac output = O2 Consumption / [O2] pul vein - [O2] pul art
- Measure oxygen consumption for the whole body
- measure pulmonary vein [O2] in systemic arterial blood
- measure pulmonry artery [O2} in systemic mixed venous blood
How are cardiac output, stroke volume, and heart rate related?
CO = SV x HR
What is the determining factor that controls how much blood the heart pumps out?
- Venous return
- it is the amount of blood returning to the heart that determines how much blood the heart pumps out
The cardiovascular system consists of two pumps and two circuits that are connected in ________?
Series
What are the 2 pumps of the cardiovascular system?
The left and right ventricles
Name the two the circuits of the cardiovascular system.
- Pulmonary circuit
- Systemic circuit
Because the 2 circuits of the cardiovascular system are in series what must be true about flow in the 2 circuits?
Flow must be equal in the 2 circuits
Because the 2 circuits of the cardiovascular system are in series, what is the relationship between cardiac output and flow of the 2 systems?
Cardiac output and rate of the 2 systems of the two circuits are equal
Because the 2 circuits of the cardiovascular system are connected in series, what relationship exists between the pressures of the 2 circuits?
All pressures are higher in the systemic circuit
Because the 2 circuits of the cardiovascular system are in series, the chemical composition os pulmonary venous blood is similar to that of _________ _________ blood?
Systemic arterial
Because the 2 circuits of the cardiovascular system are in series, the chemical composition of venous blood entering the right atrium is the same as the composition of _______ ________ blood?
Pulmonary arterial
Name 3 of the 4 factors that directly affect cardiac output.
- Basic level of body metabolism
- Whether the person is exercising
- Age
- Size of the body
What are the normal cardiac output values for healthy young men, women, and the resting adult?
- healthy young men- 5.6 L/min
- Women - 4.9 L/min
- Resting adult 5.0 L/min