How many milliliters of blood does a human body have?

The amount of blood in the human body is related to one's physique. The stronger the physique of a person, the colder the blood is. A person weighing 100 kilograms has about 4000 milliliters of blood, and the largest component of blood is water. When a person loses 30% of their blood, their life will be in danger and they need to replenish their blood in time. When giving a blood transfusion, it is important to check the blood type to see if it matches.

The blood volume of a healthy adult is about 8% of body weight. If you weigh 50 kg, you have about 4000 ml of blood. About 80% of this blood participates in blood circulation, and the remaining 20% ​​is stored in the liver, spleen, lungs and capillaries, which are called the "small blood banks" of the human body. The impact of blood loss on the human body varies with the amount of bleeding and the rate of bleeding. If the amount of blood loss is less than 10% of the total blood, the human body only needs to mobilize the stored blood to participate in the circulation, and there will be no obvious discomfort. If the amount of blood loss reaches 20% of the total blood volume, the body's compensation is still insufficient to maintain normal levels of blood volume and blood pressure, which will affect a person's life activities. If the amount of blood loss exceeds 30% in a short period of time, it will be life-threatening if blood transfusion is not timely.

Generally speaking, an adult may not have obvious symptoms when losing 500 ml of blood. When the amount of blood loss is more than 800 ml, symptoms such as pale face and lips, cold sweat on the skin, cold and weak hands and feet, rapid breathing, and a fast and weak pulse will appear. When the amount of blood loss reaches more than 1500 ml, it can cause insufficient blood supply to the brain, and the injured person will experience symptoms such as blurred vision, thirst, dizziness, confusion or restlessness, or even coma. The total blood volume of a healthy normal adult is approximately 8% of body weight. A person weighing 50 kg has a total blood volume of 4 kg, or approximately 4000 ml. When blood loss is less than 10% of the total amount, it has no obvious effect on human health. Blood loss of 800ml-1000ml (net blood volume) or 20% of the total blood volume will cause shock.

Under normal circumstances, the total blood volume in a person's body is about 8% of body weight. If the body weight is 100 catties, the blood volume is 8 catties. That is 4 kilograms. The total volume is 4000 ml, of which plasma accounts for more than half. The blood volume of a healthy person is not fixed. It varies between different individuals and also changes under different conditions of the same individual. Generally speaking, men have more blood than women; obese people have more fat, so the blood volume per kilogram of body weight is less than normal.