Question

As part of a blood drive on campus for the american red cross, you and your friends have just donated 500 ml of blood. you are now relaxing at the student lounge, waiting for a&p lab to begin. unfortunately, even though you are thirsty, you haven't bothered to buy yourself a drink. other than a little soreness of the skin and tissue around your median cubital vein, you feel fine. how has your 500 ml decrease in blood volume most likely affected your cardiac output, heart rate, and stroke volume?

Answer 1

Due to a reduction in blood volume due to blood donation, the stroke volume will decrease. However, to compensate for this, your heart rate will increase so as to maintain your cardiac output. Cardiac output is stroke volume multiplied with heart rate.
Maintaining normal cardiac output is critical so the whole body receives enough nutrients and oxygen.