PaO₂
ABGNormal range
80–100 mmHg
SI: 10.6–13.3 kPa
Critical low: < 60 mmHg
☎ When to call
PaO₂ < 60 or falling despite increased O₂ — escalate with the FiO₂, device, and work of breathing.
What you do
- < 60 on room air ≈ SpO₂ ~90% — this is the cliff edge of the oxyhemoglobin curve
- Always chart the FiO₂ with the PaO₂ — 90 on room air and 90 on 100% FiO₂ are different diseases
Causes of HIGH pao₂
Causes of LOW pao₂
Source: Pagana, Mosby's Manual of Diagnostic and Laboratory Tests, 7th ed.Reference only — verify against your facility's policy.
