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Respiratory

Arterial Oxygen Content (CaO₂)

Total oxygen carried in arterial blood — bound to haemoglobin plus dissolved.

Written for clinicians. If you're a parent or patient, don't act on these numbers — talk to your child's doctor.

Inputs

FieldUnitNotes
Haemoglobin g/dL 2–25
Arterial O₂ saturation (SaO₂) % 30–100
PaO₂ (optional) mmHg For the small dissolved term

FAQ

What is the Arterial Oxygen Content (CaO₂)?

Total oxygen carried in arterial blood — bound to haemoglobin plus dissolved.

What inputs does the Arterial Oxygen Content (CaO₂) need?

Haemoglobin (g/dL), Arterial O₂ saturation (SaO₂) (%), PaO₂ (optional) (mmHg).

Related guides

Arterial Oxygen Content (CaO₂): Why Haemoglobin Beats Saturation

Arterial oxygen content CaO₂ — the bound-plus-dissolved formula, why anaemia matters more than a small SaO₂ dip, its role in oxygen delivery (DO₂), and a worked example.

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Difference between alveolar and arterial oxygen tension — assesses the cause of hypoxaemia (gas-exchange defect vs hypoventilation).

Oxygen Saturation Index (OSI)

Non-invasive oxygenation severity index (uses SpO₂ instead of PaO₂) for grading pediatric ARDS (PALICC).

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