Estimated Blood Volume
Choose a method and enter anthropometric data to calculate total blood volume. Provide hematocrit to split into plasma and red cell components.
Used to partition blood volume into plasma and red cell volumes.
Total blood volume
4985 mL
(4.98 L)
Plasma volume
2891 mL
Red cell volume
2094 mL
How to Use This Calculator
Select the estimation method
Nadler requires height and weight and is more precise; simplified uses weight-based factors (75 mL/kg male, 65 mL/kg female).
Provide anthropometric data
Enter height in centimeters and weight in kilograms. Consider using ideal or lean body weight for obese patients.
Interpret results for clinical planning
Use total blood volume to guide transfusion strategy, estimate allowable blood loss, or plan exchange transfusions.
Formula
Nadler (male) = 0.3669 × (Height(m))³ + 0.03219 × Weight(kg) + 0.6041
Nadler (female) = 0.3561 × (Height(m))³ + 0.03308 × Weight(kg) + 0.1833
Simplified = Weight(kg) × Factor (male 75 mL/kg, female 65 mL/kg)
Plasma volume = TBV × (1 − Hematocrit); Red cell volume = TBV × Hematocrit
Full Description
Estimated blood volume (EBV) is crucial for perioperative blood management, trauma resuscitation, and pharmacokinetic dosing. The Nadler formula incorporates height and weight for accuracy, whereas weight-based factors are suitable for quick estimates. Adjust EBV for specific populations (pregnancy, obesity, pediatrics) and monitor laboratory trends to validate estimates during clinical care.
Frequently Asked Questions
When should I use Nadler vs simplified?
Use Nadler when height and weight are known and precision matters. Simplified factors are acceptable for rapid approximations.
How do I adjust for obesity?
Consider using adjusted or lean body weight in obese patients to avoid overestimating blood volume.
Does hematocrit affect total blood volume?
Hematocrit partitions blood volume into plasma and red cell components but does not change total blood volume in the equation.
Can this inform transfusion thresholds?
Combine EBV with allowable blood loss and hemoglobin targets to plan transfusions, but always use clinical judgment and guidelines.