PRBC Bag Volume
A standard packed red blood cell (PRBC) bag contains approximately 300 mL of volume, though this can range from 270-330 mL depending on preparation methods. 1, 2
Standard Volume Specifications
- The typical PRBC unit volume is approximately 300 mL after plasma removal from whole blood donation 1, 2
- Hyperpacked preparations can reduce volume to 180 mL (shelf-stored) or 162 mL (previously frozen RBCs) with hematocrits of 90-98%, though these require washing and take longer to administer 3
- Conventionally packed unwashed red blood cells have volumes of 270-330 mL 3
Clinical Relevance of Volume
Each 300 mL unit of PRBCs typically raises hemoglobin by 1 g/dL or hematocrit by 3% in normal-sized adults without concurrent blood loss 1
- This hemoglobin increment applies specifically to hemodynamically stable patients not experiencing ongoing hemorrhage 1
- Larger patients may require more blood volume to achieve the same hemoglobin increment 1
- The actual hematocrit increase per liter of PRBCs transfused averages 6.4% ± 4.1%, which translates to approximately 1.9% ± 1.2% per 300 mL unit 2
Important Caveats
- Substantial variability exists in transfusion response due to fluid resuscitation status, dehydration, patient age, and persistent hemorrhage 2
- The iron contained in transfused red cells (147-278 mg per unit) is NOT immediately available for erythropoiesis, as it is only released after phagocytosis of senescent cells over their 100-110 day lifespan 1