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Transfusion Requirements Calculator
Hematology / Transfusion Medicine
Estimates the volume of packed red blood cells (pRBCs) and number of units required to raise hemoglobin to a target level. Based on estimated blood volume (Nadler formula) and average hemoglobin content of stored pRBC units (~22 g/dL).
Transfusion Thresholds
| Clinical Setting | Hgb Threshold | Notes |
|---|---|---|
| ICU (stable) | <7 g/dL | Restrictive transfusion strategy |
| Non-ICU (stable) | <8 g/dL | — |
| Cardiac surgery | <8–9 g/dL | Higher threshold in ACS |
| Active bleeding | Individualize | Based on symptoms and hemodynamics |
Formula
EBV (Nadler) — Male: 0.3669×H³ + 0.03219×W + 0.6041
Volume to transfuse = EBV × (Target Hgb − Current Hgb) / Hgb_pRBC
Units = Volume / Volume per unit
Hgb_pRBC assumed = 22 g/dL
Volume to transfuse = EBV × (Target Hgb − Current Hgb) / Hgb_pRBC
Units = Volume / Volume per unit
Hgb_pRBC assumed = 22 g/dL
For educational use only. Clinical decisions must incorporate full patient evaluation.
