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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Blood Gases and O2 Saturation


CPT Code(s): 82805

Test Description: Test Components: pH, pCO2, pO2, base excess, actual bicarbonate, oxygen saturation and oxygen content.

Methodology: Electrode/Spectrophotometry

Days Performed: Daily, 24 hours.

Turnaround Time: Stat: Up to 30 minutes. All requests processed stat.

Specimen Requirements

Specimen: Arterial, venous, or capillary

Patient Preparation: None.  For venous samples on outpatients, send patient to UWHC Outpatient Phlebotomy to be drawn.

Collection Instructions: Radiometer "PICO"® syringes must be free of bubbles and clots. Two full Radiometer capillaries free of air bubbles and clots are needed for capillary blood.

Collection Container: Preferred: Radiometer PICO® syringe
Also Acceptable: 2 full Radiometer capillary tubes

Collection Volume: Preferred: 1.5 mL
Pediatrics: 0.5 mL

Sample Analyzed: Whole Blood

Volume Required: Preferred: 1.5 mL
Pediatrics: 0.5 mL

Specimen Transport: Transport specimen to UWHC Core Lab (B4/220) immediately.  Specimen must arrive in the Core Lab within 30 minutes of collection.

Unacceptable Criteria: Clotted specimens, specimens with air, or specimens past stability time are not acceptable.

Stability: Ambient: 1 hour
Frozen: Not acceptable


Reference Interval:



 pH 10 days and up:



0 days-23 months:

24 months and up: 

27-41 mmHg

34-46 mmHg  



 pO2, resting 1 day and up:  80-90 mmHg 
 Base Excess 18 years and up:  -2.5 to +2.5 mmol/L 



18 years and up:  22.0-26.0 mmol/L 





1 year and up: 95.0-98.0% 


 1 year and up:   15.0-22.0 mL/dL 


Critical Calls: View

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