blood bag

A small bag full of blood, which has been collected from the patient or from a blood donor in order to replace that patient's blood should there be a lot of blood loss during surgery, or from exsanguination due to a critical injury.

Different patients/donors' blood is collected, analyzed and grouped according to blood type, of which there are four: A, B, AB, and O, depending upon inherited antigens. There is also the + and - status to indicate if the Rh factor (or Rhesus factor) is present.

Blood bags are often seen hanging from intravenous stands in hospitals near the patient's bed.

This tag implicates blood (learn more).