Universal donor

A universal donor refers to a blood type (O negative) that can be safely transfused to patients of almost any other blood type because it lacks specific antigens that typically trigger immune reactions. In blood transfusions, compatibility is crucial to prevent the body from rejecting the donor blood. O negative blood is considered universal because it has no A, B, or Rh antigens, making it suitable for emergency situations when the patient's blood type is unknown. However, it is still important to match as closely as possible to ensure safety and effectiveness in transfusions.