The precautions of blood perfusion are as follows: 1, the patient’s coagulation status should be assessed and appropriate anticoagulant should be selected before treatment; 2, the blood flow rate of blood perfusion is generally 100-200 ml per minute, the perfusion device needs to be changed every 2 hours, and the duration of each perfusion treatment should not exceed 6 hours; 3, during the perfusion process, if the patient has a drop in blood pressure, the blood pump speed needs to be reduced, appropriate expansion, and if necessary, antihypertensive drugs should be used again; 4, half an hour to one hour after the start of perfusion, if the patient has symptoms such as chills, fever and dyspnea, dexamethasone and oxygen can be given appropriately, and if there is no relief, then the perfusion treatment should be stopped.