Red Blood Cell Transfusion Volume Calculator
Estimate the number of packed red cell units and total volume needed to raise haemoglobin to a target value in an adult.
How to Use the Red Blood Cell Transfusion Volume Calculator
- Enter patient weight in kg.
- Enter current haemoglobin in g/L.
- Enter target haemoglobin in g/L.
- Click Calculate to see estimated units and total volume.
Cas d'utilisation
- •Estimating RBC needs for anaemic adults.
- •Planning perioperative blood product orders.
- •Teaching transfusion medicine fundamentals.
Formule
Blood volume ≈ weight × 70 ml/kg. One RBC unit (~280 ml) raises haemoglobin by ~10 g/L in a 70 kg adult. Units ≈ ceil((Hb target − Hb current) / 10).
Questions fréquemment posées
What haemoglobin target should I use?
Most guidelines recommend a restrictive threshold: transfuse at Hb 70 g/L targeting 70–90 g/L for stable patients, 80 g/L for cardiac disease. Individual targets must be set clinically.
Does each unit really raise Hb by 10 g/L?
The ~10 g/L per unit rule is a rough average for a 70 kg adult. Smaller patients, active bleeding, and splenic sequestration change the response. Recheck Hb after transfusion.
Disclaimer
For educational purposes only. Transfusion decisions require full clinical assessment and informed consent.