Department
Chemical Pathology
Delphic Registration Code (Alpha Code)
EP50
Test Code (Numeric Code)
4503
Laboratory Handling
Sample Stability
30 mins
Synonyms
P50; Oxygen Dissociation Curve, Oxygen p50
Turnaround Time
30 minutes
Available 24 hours
Specimen Type
- Whole Blood
Specimen Requirements
Tube/Container Type:
Preferred
- Blood Gas Syringe
Acceptable
- Lithium Heparin - Non-gel (Green Cap)
Preferred Sample Volume (ml)
3
Minimum Sample Volume (ml)
1
Paediatric Specimen Requirements
Tube/Container Type:
Preferred
- Blood Gas Syringe
Minimum Sample Volume (ml)
0.3
Additional Specimen Information
Preferred sample: blood gas balanced heparinised syringe absolute minimum volumes:
3 mL blood gas syringe: - 1.0 mL
1 mL blood gas syringe: - 0.3 mL
May use a dedicated (cannot be shared with other biochemistry tests) 4 mL plain non-gel heparin tube (dark green top) to be fully filled to minimise air exposure.
An arterial blood sample is unsuitable for P50 analysis. A venous sample is required.
Last updated: 14/09/2026