The determination of blood volume deficiency can be based on symptoms, signs, medical history and laboratory tests and other indicators to determine, if there is traumatic bleeding in the amount of about 1000ml, there will be mild shock, shock is still accompanied by consciousness, only the appearance of consciousness, indifferent expression, skin mucous membrane color pale, body temperature decreased, urine volume decreased, pulse fine and accelerated, blood pressure decreased, etc.. If the bleeding continues to increase, superficial veins throughout the body collapse and disappear. In addition, the main laboratory tests, such as routine blood tests found that there is a significant decrease in red blood cells, hematocrit, systolic blood pressure less than 90mmHg, pulse pressure difference less than 20mmHg, etc. are all symptoms of shock.