What Is the Oxygen Delivery (DO₂) & Extraction Ratio Calculator?
DO2 is the total volumetric rate of oxygen transported from the left ventricle to the peripheral microcirculation per minute.
How Does the Oxygen Delivery (DO₂) & Extraction Ratio Calculator Work?
Computes arterial oxygen content CaO₂ summing bound (1.34·Hb·SaO₂) and dissolved (0.0031·PaO₂) oxygen.
Multiplies by cardiac output to determine DO₂.
Evaluates tissue extraction ratio OER = VO₂ / DO₂.
Oxygen Delivery (DO₂) & Extraction Ratio Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
CaO₂ = 1.34·Hb·(SaO₂/100) + 0.0031·PaO₂, DO₂ = CO · CaO₂ · 10, OER = VO₂ / DO₂
Hüfner equation for oxygen content and systemic volumetric delivery.
How to Use the Oxygen Delivery (DO₂) & Extraction Ratio Calculator
- Enter cardiac output, hemoglobin, and arterial/venous blood gas saturations.
Step-by-Step Example Calculation
Resting Adult Oxygen Delivery
Input Values:
cardiacOutput:5
hemoglobin:14
saO2:98
paO2:95
svO2:75
Worked Steps: Normal resting adult delivering ~930 mL O2/min with 23% extraction ratio.
Understanding Your Result
Normal DO₂: 900 to 1,100 mL/min.
Normal OER: 20% to 30%.
OER > 50% indicates critical supply-dependency and tissue hypoperfusion.
Factors That Affect the Result
- Hemoglobin concentration, cardiac output, and arterial oxygenation.
When Should You Use This Calculator?
- Goal-directed therapy in shock, high-risk surgery, and trauma resuscitation.
Assumptions & Limitations
- Uses Hüfner binding constant 1.34 mL O2/g Hb.
Frequently Asked Questions
Calculation Accuracy & Reference Note
Standard physiological oxygen transport equations.