The amount of blood transfusion is mainly based on the patient’s condition. For neurosurgical critical patients, the basic requirement is that the hemoglobin must be more than 100g/L. For patients with combined compound injuries, such as liver and spleen rupture, these patients have more blood loss and need active blood preparation before and during surgery, with a maximum of 5000~6000 ml of blood transfusion.The amount of blood transfusion is mainly based on the patient’s condition. For some patients with abnormal hematopoietic function, they may need blood transfusion treatment every day, and then their overall blood transfusion volume will be more.