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🩸 Arterial Oxygen Content (CaO₂)

UseQuantify oxygen content for delivery and shunt calculations.

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SourceMarino PL. The ICU Book

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
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This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

Scene next step
📋circ hemoOpen scene pack →
Related scores
Score + version; reference only — not a substitute for care · no HIS write

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Methodology · worked example, guidelines & full notes
Clinical takeaway

Most oxygen is bound to haemoglobin; dissolved O₂ is small.

When to use

Quantify oxygen content for delivery and shunt calculations.

How it works

CaO₂ = 1.34 × Hb × SaO₂ + 0.0031 × PaO₂. Normal ≈ 18–20 mL O₂/dL.

Key points

  • Most oxygen is bound to haemoglobin; dissolved O₂ is small.
  • Anaemia lowers content despite a normal SaO₂.
  • Feeds into DO₂ and oxygen extraction calculations.

References

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

Haemoglobin15 g/dL
SaO₂98 %
PaO₂100 mmHg

→CaO₂20.0mL O₂/dL

  • Bound to Hb：19.7 mL/dL
  • Dissolved：0.31 mL/dL
  • Formula：1.34 × Hb × SaO₂ + 0.0031 × PaO₂
Verification & sources · governance
FAQ

Frequently asked questions

What are the limits and cautions when using Arterial Oxygen Content (CaO₂)?
For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
Does Arterial Oxygen Content (CaO₂) upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is Arterial Oxygen Content (CaO₂) calculated in practice? Can you show a worked example?
Inputs: Haemoglobin 15 g/dL, SaO₂ 98 %, PaO₂ 100 mmHg → Result: CaO₂ 20.0 mL O₂/dL（Bound to Hb: 19.7 mL/dL, Dissolved: 0.31 mL/dL, Formula: 1.34 × Hb × SaO₂ + 0.0031 × PaO₂）
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