3.2.8- Cardiac Output

Question 1

What does cardiac output mean?

Answer 1

Cardiac output (CO) is the term used to describe the volume of blood that is pumped by the heart (the left and right ventricle) per unit of time
An average adult has a cardiac output of roughly 4.7 litres of blood per minute when at rest
Individuals who are fitter often have higher cardiac outputs due to having thicker and stronger ventricular muscles in their hearts
Cardiac output increases when an individual is exercising
This is so that the blood supply can match the increased metabolic demands of the cells

Question 2

How is cardiac output calculated?

Answer 2

Cardiac output = heart rate x stroke volume

Heart rate- the number of times a heart beats a minute (number of cardiac cycles)
Stroke Volume- the volume of blood pumped out of the left ventricle during one cardiac cycle.