In an emergency with limited type O-negative RBCs, O-positive RBCs are reasonable for transfusion except for which patient group?

In an emergency with limited type O-negative RBCs, O-positive RBCs are reasonable for transfusion except for which patient group?

• A. A 60-year-old woman with diabetes after a motor vehicle accident
• B. A 23-year-old man with a gunshot wound to the upper abdomen
• C. An 84-year-old man with a ruptured abdominal aortic aneurysm
• D. A 21-year-old pregnant woman with placenta previa who is bleeding profusely

Answer: (D)

Rh compatibility matters in transfusion. O-negative blood is the universal donor, but O-positive blood can be given to most patients, except those who could become pregnant or are currently pregnant, because Rh-positive cells can trigger the development of anti-D antibodies in an Rh-negative recipient. If a pregnant woman receives Rh-positive blood, she may become alloimmunized, and these anti-D antibodies can cross the placenta and cause hemolytic disease in current or future pregnancies. In a bleeding pregnant patient, using Rh-positive blood risks sensitization and harm to the fetus, so Rh-negative blood is preferred when possible. The other listed patients are men or a non-pregnant woman, for whom Rh-positive blood is acceptable in an emergency if needed. Therefore, the pregnant woman with placenta previa is the group for whom Rh-positive transfusion is inappropriate.

Rh compatibility matters in transfusion. O-negative blood is the universal donor, but O-positive blood can be given to most patients, except those who could become pregnant or are currently pregnant, because Rh-positive cells can trigger the development of anti-D antibodies in an Rh-negative recipient. If a pregnant woman receives Rh-positive blood, she may become alloimmunized, and these anti-D antibodies can cross the placenta and cause hemolytic disease in current or future pregnancies. In a bleeding pregnant patient, using Rh-positive blood risks sensitization and harm to the fetus, so Rh-negative blood is preferred when possible. The other listed patients are men or a non-pregnant woman, for whom Rh-positive blood is acceptable in an emergency if needed. Therefore, the pregnant woman with placenta previa is the group for whom Rh-positive transfusion is inappropriate.