How long does it take to transfuse a unit of blood?
This depends on the condition for which transfusion is being given. If the patient is being transfused to replace blood for sudden massive blood loss, one unit of blood may be given rapidly in about 10-15 minutes. However, if the blood transfusion is being given for anaemia, it may take over 3-4 hours. Normal rate of transfusion is 28 drops per minute.