What would happen to someone if they only have 4 pints of blood in their body?
We don’t usually measure blood that way. We look at the percentage of red blood cells compared to the blood as a whole – that is called hematocrit. There is also the idea of volume status. If there isn’t enough blood volume (as can happen with severe dehydration), the person is hypovolemic. With sudden blood loss of 60% (as your question suggests), the person would be in hemorrhagic shock and would likely suffer heart, kidney and/or brain damage. Without immediate medical care, blood loss of that magnitude would be fatal. If the blood volume was normal, but the person lost 60% of his/her red blood cells, he/she would have severe anemia. If it happens slowly, over a long time, people will feel fatigued, tire easily, be pale, have no exercise tolerance, feel cold and other vague symptoms. Sudden anemia of that magnitude would be poorly tolerated, and might cause a heart attack, fainting, and other more serious problems. Anemia is caused by either not making enough red blood cells, or los
