Test Overview
Test Methodology

Abbott I-Stat - ion selective potentiometry

Test Usage

pH, pCO2, pO2 measurements are used in the diagnosis, monitoring, and treatment of respiratory disturbances and metabolic and respiratory-based acid-base disturbances.

Reference Range *

Reference ranges are available in the iSTAT CG4+ Blood Gas and Lactate test procedure located on the POC website: https://www.pathology.med.umich.edu/point-of-care.

Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

Results may be affected in the following situations: hemolysis, traumatic draw, pumping fist during draw, extended delay between drawing and testing specimen, exposure to air when measuring blood gases, and obtaining specimen from an arm with an IV.

Test Details
Analytic Time

2 minutes

Soft Order Code
MiChart Code
POC Venous BG, I-Stat
Point of Care
Point of Care
Specimen Requirements
Special Handling

Samples collected without anticoagulant must be tested immediately, within 3 minutes of draw time. Samples collected in anticoagulant must be tested within 10 minutes of draw time. Expel air bubbles and thoroughly mix syringe samples for >30 seconds by repeatedly inverting and rolling syringe immediately after sample collection.

Normal Volume
3 mL whole blood
Minimum Volume
95 µL whole blood
Rejection Criteria
Specimens; older than 30 minutes, containing bubbles, having prolonged exposure to room air, clotted, and/or grossly hemolyzed.
Additional Information

For more test specific information, please refer to the test procedure found on the Michigan Medicine POC website: https://www.pathology.med.umich.edu/point-of-care

CPT Code
NY State Approved