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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Blood Gases

Test Code(s): BGAS / HCBGAS

CPT Code(s): 82803

Test Description: Test Component:

pH, pCO2, pO2, base excess, and actual bicarbonate.

Methodology: Electrode

Request Form: UWHC DOWNTIME Laboratory Request Form (UWH IPDOWNTIME, 4004202); Write in test if not on form.

Days Performed: Daily, 24 hours.

Turnaround Time: Stat: Less than 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 Laboratory (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:

Arterial specimen


1 day to 10 days:


  11 days and up: 7.36-7.44 
0 days to 23 months:  27-41 mmHg
  24 months and up: 34-46 mmHg
pO2, resting 1 day and up: 80-90 mmHg 
Base Excess 0 days to 30 days: -10.0 to -2.0 mmol/L       
  31 days to 12 months: -7.0 to -1.0 mmol/L
  1 year to 17 years: -4.0 to +2.0 mmol/L
  18 years and up: -2.5 to +2.5 mmol/L
Actual Bicarbonate  0 days to 30 days: 17.0-24.0 mmol/L
  31 days to 60 days: 19.0-24.0 mmol/L
  2 months to 2 years: 16.0-24.0 mmol/L
  3 years and up: 22.0-26.0 mmol/L

Critical Calls: View

pCO2 pO2 pH base excess actual bicarbonate

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