Allowable Blood Loss using Gross's formula: ABL = EBV × (Hᵢ − H_f) ÷ Hᵢ
Result
1,750mL
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EBV = 70 kg × 70 mL/kg = 4900 mL
ABL = EBV × (Hi − Hf) ÷ Hi
ABL = 4900 × (42 − 27) ÷ 42
ABL = 1750 mL
Clinical note: ABL estimates the volume of blood loss tolerated before transfusion becomes appropriate. Use alongside hemodynamics, ongoing-loss rate, and patient-specific transfusion triggers. Education only — not a substitute for clinical judgment.