PediRounds

Acid–base / gases — paediatric reference ranges

5 reference ranges. Values vary by laboratory, assay and age — always check the range printed on your own report.

TestSpecimenReference range
pH (arterial)Blood gas7.35–7.45
PaCO₂Blood gas35–45 mmHg (4.7–6.0 kPa)
PaO₂Blood gas80–100 mmHg (10.6–13.3 kPa)
Base excessBlood gas−2 to +2 mmol/L
LactateBlood<2.0 mmol/L

Common questions

What is the normal ph (arterial) level in children?

pH (arterial) (Blood gas): 7.35–7.45.

Which acid–base / gases tests are covered?

pH (arterial), PaCO₂, PaO₂, Base excess, Lactate.

About this page

Compiled from standard paediatric references. Interpret against the child's clinical state and the ranges used by your own institution or laboratory.

Spotted something wrong? Report an error on this page — corrections from clinicians are welcome and are reviewed before any change is published.

Last reviewed 2026-08-12.