What is Cardiac Output?
Cardiac output is the amount of blood pumped from one of the ventricles each minute
How is cardiac output defined?
stroke volume x heart rate
Co=70ml X 75= 5250ml or 5.2 liters
What is normal resting cardiac output
What is Stroke Volume?
The volume of blood ejected by the ventricle each contraction
What is cardiac reserve?
The difference between a person's maximum cardiac output and the a person's cardiac output at rest
What is the average cardiac output reserve for most people?
4-5 times greater then resting reserve
What is the cardiac reserve for most athletes?
7-8 times greater then resting value
how do you define stroke volume?
need to figure out
What three factors regulate stroke volume?
What is preload?
The degree of stretch before the heart contracts
What is contractility?
The forcefulness of contraction of individual ventricular muscle fibers
What is afterload?
The pressure that must be exceeded before ejection of blood from the ventricles can occur
What is Frank-Starling law of the heart?
The more the heart fills with blood during diastole, the greater the force of contraction during systole
What two factors determine End Diastolic Volume? EDV
1-duration of ventricular diastole
2-venous return, the volume of blood returning to the right ventricle
What is the normal afterload in the aorta?
What is the afterload of the pulmonary trunk?
20mmHg in the pulmonary trunk
What three factors regulate heart rate?
1-Autonomic Nervous system
3-Other factors, such as age, gender and body temperature
what part of the nervous system controls heart rate?
The cardiovascular control center in the medulla oblongata,though sympathetic and parasympathetic systems
What cranial nerve carries the 411 to the heart from the nervous system?
Where is the cardiovascular center located in the body?
In the medulla oblongata
What chemicals and ions regulate heart rate?
hormones such as epinephrine and norepinephrine, thyroid hormone and ions such K+, Ca++ and Ca+