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BLOOD GASES
(WHOLE BLOOD)
Alternate Names: ABG, Arterial Blood Gases
Test includes: pH
pO2
pCO2
HCO3 (bicarbonate)
TCO2 (total CO2)
O2 Saturation
BE (base excess)
Performed: Daily, 24 Hours
Methodologies

pH:
pH electrode

pO2:
O2 electrode (amperometric)

pCO2:
CO2 electrode

HCO3 (bicarbonate):
calculated by instrument

TCO2 (total CO2):
calculated by instrument

O2 Saturation
calculated by instrument

BE (base excess):
calculated by instrument
Turnaround Time: Routine: 4 hours
Stat: < 1 hour (if procured by laboratory)

Container / Specimen Requirements

 All specimens (or requisitions) should indicate the level of O2 administration.
    Container / Tube: Heparinized syringe
or capillary tube
    Minimum Volume: 0.5 ml
Special Handling or Timing of Specimen: All specimens should be on ice and delivered to the laboratory immediately
Preparation of Patient: None
Reference Ranges

pH

arterial:
7.35 - 7.45

venous:
7.320 - 7.420

Critical Values:
<7.30 or >7.55

pO2

arterial:
70 - 100 mmHg

venous

 25 - 40 mmHg

Critical Values:

adults:

 <55 mmHg

neonate:

 <44 mmHg

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pCO2

arterial:

 35 - 45 mmHg

venous:

 41 -51 mmHg

Critical Values:
<20 mmHg or >60 mmHg

HCO3 (bicarbonate)

arterial:
22 - 26 mmol/L

venous:
24 - 28 mmol/L

Critical Values:
<10 mmol/L and >40 mmol/L

TCO2 (total CO2)

arterial:
23 - 27 mmol/L

venous:
25 - 29 mmol/L

Critical Values:
<10 mmol/L or >40 mmol/L

O2 Saturation

arterial:
96% - 97%

venous:
40% - 70%

BE (base excess)
- 2 to +2

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Causes for Specimen Rejection:  Improper labeling.
Presence of large air bubbles.
Specimen not on ice.
Specimen clotted.
CareManager Test Group:
CareManager Name/Alias:		 LAB
ABG
Specimen Labeling: Click here for policy