Critical Care · Cardiology
Oxygen Extraction Ratio (O₂ER) calculator
Enter the published formula inputs below to calculate and interpret this score.
Clinical inputs
Result
Complete all required inputs to calculate the score.
Formula inputs
- o2er hemoglobin g dl (g/dL)Accepted range: 3 to 25
- o2er sao2 percent (%)Accepted range: 50 to 100
- o2er svo2 percent (%)Accepted range: 20 to 90
Primary source
Oxygen extraction ratio O₂ER (%) = (CaO₂ − CvO₂) / CaO₂ × 100 derived from arterial and mixed-venous oxygen contents. DOI: 10.1164/ajrccm.158.1.9711041. PMID: 9655694. Scope: adult perfusion monitoring; typical resting extraction about 22–30%. (1998)
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