How much blood can a person lose and still live?
40% or greater is usually considered the maximum amount of blood that an adult can loose before the body can no longer compensate. In an 80 kg adult this would be about 2.24 liters. A Class I Hemorrhage is usually considered 15%, or less, of an adult’s blood volume. In an 80 kg person this would be about 0.84 liters. At this level there are almost no signs or symptoms. A Class II Hemorrhage is 15 to 30% loss of an adult’s blood volume. In an 80 kg person this would be about 1.68 liters. At this level the heart will start to beat faster, and the person will start to look pale, and feel cool. This is the beginning stages of shock. A Class III Hemorrhage is 30 to 40% loss of blood. In an 80 kg person this would be about 2.24 liters. At this level the heart will be beating very fast, trying to keep up with the bodies needs. The person will look very pale, and start to be confused. This person is in shock, and in trouble. Fluids are needed very quickly. A Class IV Hemorrhage is as described
