Patient Parameters
kg
g/dL
g/dL
Estimated Blood Volume
4,900
mL
EBV factor used70 mL/kg
Formula
Male: 70 mL/kg
Female: 65 mL/kg
Obese: 60 mL/kg
EBV = Weight × Factor
Female: 65 mL/kg
Obese: 60 mL/kg
EBV = Weight × Factor
Allowable Blood Loss (ABL)
3,267
mL before transfusion trigger
Hgb drop allowed14 → 7 g/dL
% of EBV67%
Formula
ABL = EBV × (Hgbi - Hgbt) / Hgbavg
where Hgbavg = (Hgbi + Hgbt) / 2
where Hgbavg = (Hgbi + Hgbt) / 2
Fluid Replacement Ratios
Crystalloid (3:1)9,801 mL
Colloid (1:1)3,267 mL
pRBC (1:1)3,267 mL
For blood loss up to ABL
Replace 1 mL blood loss with:
• 3 mL crystalloid, OR
• 1 mL colloid/albumin
• 3 mL crystalloid, OR
• 1 mL colloid/albumin
Transfusion Estimates
1 unit pRBC raises Hgb by~1 g/dL
Units to reach Hgb 103 units
Expected Hgb after 2 units9 g/dL
Rule of thumb
1 unit pRBC ≈ 300 mL
Raises Hgb ~1 g/dL in 70 kg adult
Raises Hct ~3%
Raises Hgb ~1 g/dL in 70 kg adult
Raises Hct ~3%
Intraoperative Blood Loss TrackerEBL: 0 mL
mL
Blood Loss vs ABL0% of ABL
0%50%100% (Transfuse)
EBV Reference by Patient Type
| Patient Type | mL/kg | 70 kg Example |
|---|---|---|
| Adult Male | 70 | 4,900 mL |
| Adult Female | 65 | 4,550 mL |
| Obese Adult | 60 | 4,200 mL |
| Infant (1-12 mo) | 80 | — |
| Neonate (term) | 85-90 | — |
| Premature neonate | 95-100 | — |