UCSF Clinical Laboratories Test Directory

Ordering

Ordering Recommendations

Follow the link for information about Blood Gas Panels that contain this test.

Available Stat

Yes

Performing Lab

Parnassus, Mission Bay and Mt Zion Chemistry

Performed

Test available 24 hours per day 7 days per week

Methodology

Radiometer ABL 90 FLEX Plus

Reported

10 min

Additional Information

This panel includes the following:

pH (PH37), pCO2 (PCO2), pO2 (PO2), Base excess (BEX), Bicarb (HCO3) and oxygen saturation (SAO2)

All reported values are corrected to 37C unless otherwise specified. Results beyond the linear range of the instrument will be reported as < or > the extreme of the linear range. Samples containing small bubbles may be run at the laboratory's discretion. If analyzed, a comment will be added to the result regarding the presence of bubbles in the sample.

Synonyms

pH
pCO2
pO2
O2 Saturation
O2 Sat
Base excess
A-a gradient
HCO3-
ABG
BG
BE
oxygen
carbon dioxide
bicarbonate
MVBGO
CVBGO
CAPBGO
CORBGA
CORBGV
ABGCOX
VBGCOX
CVBGCX
ARTBGL
VENBGL
CVBGL
MVBGL
CAPBG
MVBGCX
CIRBGA
CIRBGV

Collection

Sample Type

Heparinized whole blood

Collect

Plastic blood gas syringe containing approximately 70 IU dry heparin in a 3 mL syringe or 23 IU in a 1 mL syringe - or a capillary tube coated with 70 IU heparin (Radiometer Clinitube).

Amount to Collect

3 mL blood

Preferred Volume

3 mL blood

Minimum Volume

1 mL blood

Remarks

Arterial puncture:
Due to the risk of arterial damage and subsequent distal ischemia, prior to puncturing an artery the RN assesses the collateral circulation. If the radial artery is to be punctured, then the pulse of the ulnar artery is assessed. If the dorsalis pedis artery is to be accessed then the posterial tibial pulse is assessed and likewise if the posterial tibial approach is used the dorsalis pedis pulse is assessed. The modified Allens's test may be used to assess collateral circulation of the ulnar artery before a radial artery puncture, but it does not always ensure adequate flow. A Doppler ultrasound flow indicator may be used to verify collateral circulation. If the collateral circulation is poor and the RN cannot palpate a pulse then the physician should be notified before proceeding. If for any reason the circulation is compromised to the extremity being assessed for arterial puncture then the physician should be notified prior to proceeding.

1. Palpate the radial artery and identify the site where the pulse is the strongest. Avoid areas with overlying veins to prevent venous admixture.
2. Prepare the patient's skin with an alcohol or 2% chlorhexidine wipe/swab.
3. Place two or three fingers along the course of the artery both to locate its position and direction, and to stabilize it.
4. Penetrate the skin smoothly holding the needle at 30-60 degree angle with the needle bevel up and pointed proximally. The angle of the “butterfly" IV catheter should not exceed 45° for pediatric patients.
5. Re-establish the position and direction of the artery by palpation.
6. Gently and slowly advance the needle or “butterfly", aiming directly for the area of maximum pulsation.
7. When the arterial lumen has been entered, less resistance is felt and blood appears in the syringe above the needle hub.
8. Obtain required amount of arterial blood for test(s).
9. If blood is not obtained on first attempt, withdraw the needle to just below the skin surface and advance needle at same angle but at 1 mm to either side of previous attempt.
10. Place the 2x2 gauze over the site of the puncture then withdraw the needle from the artery. Press firmly at the site for at least five minutes, or until the bleeding stops. Apply bandage or pressure dressing.
11. Expel any air bubble in the syringe with air filter cap placed on specimen syringe.
12. Label sample with patient's name, ID number and DOB.

Venous samples:
1. Avoid excessive venous stasis from prolonged tourniquet application or clenching of the fist prior to sample collection.
2. For central line draws make sure to waste a full red top tube then draw via the blood gas syringe as noted above.
3. Fill syringe completely, remove needle (in peripheral draws), cap sample, expel all bubbles (while holding syringe upright) until blood hits the top of cap.
4. Label sample with patient's name, ID number and DOB.

Capillary Samples:
1. The following are recommended sampling sites: earlobe, finger tip, big toe, heel. The heel and big toe are more suitable for use on neonates and infants.
2. Warm the area or puncture site for 5 to 10 minutes prior to actual sampling. This accelerates flow for blood to be representative of general status of patient.
3. Make a puncture using a lancet or similar device. Do not squeeze the area to avoid tissue juice from mixing into blood sample.
4. Wipe off the first drop of blood. Take the sample from the center of the second drop of blood and hold the capillary at a slightly downward angle for an uninterrupted blood flow. Avoid getting air bubbles in the specimen.
5. Refrain from squeezing or milking the puncture site as this may result in faulty measurements or cause hemolysis of blood sample and cause elevated K+ readings.
6. Apply accompanying caps to both ends of the capillary tube and mix the sample with the heparin immediately after collection to prevent blood from clotting. The manufacturer recommends the use of a mixing wire and magnet for capillary samples.
7. Label sample with patient's name, ID and DOB.

Deliver samples immediately to lab for testing. Samples delivered to the lab > 30 minutes after collection may yield erroneous results.

Stability (from collection to initiation)

30 min.

Unacceptable Conditions

Samples submitted > 30 min after collection. Samples with needle attached, containing large bubbles, unlabeled, mislabeled, clotted or of insufficient volume for testing.

Processing

Test Code

LAB5818 (ABGO) (blood gas from arterial source)
LAB5819 (VBGO) (blood gas from venous source)
LAB5901 (MVBGO) (blood gas from mixed venous source)
LAB5900 (CVBGO) (blood gas from central venous source)
LAB5902 (CAPBGO) (blood gas from capillary source)

LAB 5808 (CORBGA: arterial cord blood source)

LAB5809 (CORBGV: venous cord blood source)

LAB5815 (blood gas from arterial circuit source)

LAB5816 (blood gas from venous circuit source)

Test Group

Blood Gases

Performing Lab

Parnassus, Mission Bay and Mt Zion Chemistry

Preferred Volume

3 mL blood

Minimum Volume

1 mL blood

Unacceptable Conditions

Samples submitted > 30 min after collection. Samples with needle attached, containing large bubbles, unlabeled, mislabeled, clotted or of insufficient volume for testing.

Stability (from collection to initiation)

30 min.

Result Interpretation

Units

mmHg, mmol/L, %

Reference Interval

Analyte	Arterial	Venous	Mixed and central venous	Cord blood umbilical artery	Cord blood umbilical vein	Capillary
pH	7.35-7.45	7.29-7.41	7.32-7.42	7.14-7.42	7.22-7.44	0-3 days, 7.31-7.47; >3 days, 7.35-7.45
pCO2 (mmHg)	<1year: 27-41; >=1 year: 32-46	37-65	37-51	34-78	30-63	0-3 days, 29-49; >3 days, 32-46
pO2 (mmHg)	<30 days: 80-100; >=30 days: 83-108	Not applicable	Not applicable	<41	12-43	0-3 days: 33-61; 4-29 days:80-100; >=30 days: 83-108
HCO3- (mmol/L)	23-29	23-31	23-29	21-29	20-28	23-29
Base Excess (BE) (mmol/L)	-3 to 3	Not applicable	-3 to 3	-7 to 3	-6 to 2	-3 to 3
Oxygen saturation (SaO2)	95-100%	Not applicable	Mixed venous: 75-84%; central venous: 67-82%	<81%	23-94%	95-100%

Arterial reference ranges for pH and pO2 adopted from the UCSF reference range previously used with the ABL 835 blood gas analyzers.

Arterial reference range for base excess and oxygen saturation adopted from Klaestrup et al, 2011, Clin Chem Lab Med, 49(9): 1495-1500 using the ABL 837 and 725 blood gas analyzers. Arterial reference range for pCO2 (adult) and bicarbonate was adopted from Klaestrup et al, with modifications made for the ABL 90 Flex Plus analyzers. Pediatric arterial reference range for pCO2 adopted from Radiometer “Acute Care Testing Handbook,” 2014.

Venous reference ranges for pH and bicarbonate were adopted from Ress KL et al, Pathology, 2018, volume 50, supplement page S94. Venous reference ranges for pCO2 were calculated using the Robust method in MedCalc. Reference ranges were verified by running 25 male and 25 female normal volunteers from UCSF Clinical Laboratories.

Note: it is not recommended to use venous blood for assessing oxygenation status.

Critical Values

Arterial:

pH	< 7.20	> 7.55
pCO2	< 25 mmHg	> 65 mmHg
pO2 (patient age <30 days old)	< 40 mmHg	> 100 mmHg
pO2 (patient age ≥30 days old)	< 40 mmHg

Venous:

pH	< 7.20 and > 7.59
pCO2	< 20 and > 75 mm Hg

Mixed Venous:

pH	< 7.20 and > 7.59
pCO2	< 20 and > 65 mm Hg

Central Venous:

pH	< 7.20 and > 7.55
pCO2	< 20 and > 65 mm Hg

Capillary (Parnassus only):

pH	< 7.20	> 7.55
pCO2	< 25 mmHg	> 65 mm Hg

Capillary (Mission Bay and Mount Zion):

pH	< 7.20 and > 7.55
pCO2	< 25 and > 65 mmHg
pO2	0-3 days: < 33 mmHg >= 4 days: < 40 mmHg < 30 days: > 100 mmHg

Cord Blood*:

pH	< 7.0
Base excess	< -10

* Only called to ICN

Additional Information

This panel includes the following:

pH (PH37), pCO2 (PCO2), pO2 (PO2), Base excess (BEX), Bicarb (HCO3) and oxygen saturation (SAO2)

All reported values are corrected to 37C unless otherwise specified. Results beyond the linear range of the instrument will be reported as < or > the extreme of the linear range. Samples containing small bubbles may be run at the laboratory's discretion. If analyzed, a comment will be added to the result regarding the presence of bubbles in the sample.

Administrative

Complete View

Available Stat

Yes

Ordering Recommendations

Follow the link for information about Blood Gas Panels that contain this test.

Test Code

LAB5818 (ABGO) (blood gas from arterial source)
LAB5819 (VBGO) (blood gas from venous source)
LAB5901 (MVBGO) (blood gas from mixed venous source)
LAB5900 (CVBGO) (blood gas from central venous source)
LAB5902 (CAPBGO) (blood gas from capillary source)

LAB 5808 (CORBGA: arterial cord blood source)

LAB5809 (CORBGV: venous cord blood source)

LAB5815 (blood gas from arterial circuit source)

LAB5816 (blood gas from venous circuit source)

Test Group

Blood Gases

Performing Lab

Parnassus, Mission Bay and Mt Zion Chemistry

Performed

Test available 24 hours per day 7 days per week

Methodology

Radiometer ABL 90 FLEX Plus

Remarks

Arterial puncture:
Due to the risk of arterial damage and subsequent distal ischemia, prior to puncturing an artery the RN assesses the collateral circulation. If the radial artery is to be punctured, then the pulse of the ulnar artery is assessed. If the dorsalis pedis artery is to be accessed then the posterial tibial pulse is assessed and likewise if the posterial tibial approach is used the dorsalis pedis pulse is assessed. The modified Allens's test may be used to assess collateral circulation of the ulnar artery before a radial artery puncture, but it does not always ensure adequate flow. A Doppler ultrasound flow indicator may be used to verify collateral circulation. If the collateral circulation is poor and the RN cannot palpate a pulse then the physician should be notified before proceeding. If for any reason the circulation is compromised to the extremity being assessed for arterial puncture then the physician should be notified prior to proceeding.

1. Palpate the radial artery and identify the site where the pulse is the strongest. Avoid areas with overlying veins to prevent venous admixture.
2. Prepare the patient's skin with an alcohol or 2% chlorhexidine wipe/swab.
3. Place two or three fingers along the course of the artery both to locate its position and direction, and to stabilize it.
4. Penetrate the skin smoothly holding the needle at 30-60 degree angle with the needle bevel up and pointed proximally. The angle of the “butterfly" IV catheter should not exceed 45° for pediatric patients.
5. Re-establish the position and direction of the artery by palpation.
6. Gently and slowly advance the needle or “butterfly", aiming directly for the area of maximum pulsation.
7. When the arterial lumen has been entered, less resistance is felt and blood appears in the syringe above the needle hub.
8. Obtain required amount of arterial blood for test(s).
9. If blood is not obtained on first attempt, withdraw the needle to just below the skin surface and advance needle at same angle but at 1 mm to either side of previous attempt.
10. Place the 2x2 gauze over the site of the puncture then withdraw the needle from the artery. Press firmly at the site for at least five minutes, or until the bleeding stops. Apply bandage or pressure dressing.
11. Expel any air bubble in the syringe with air filter cap placed on specimen syringe.
12. Label sample with patient's name, ID number and DOB.

Venous samples:
1. Avoid excessive venous stasis from prolonged tourniquet application or clenching of the fist prior to sample collection.
2. For central line draws make sure to waste a full red top tube then draw via the blood gas syringe as noted above.
3. Fill syringe completely, remove needle (in peripheral draws), cap sample, expel all bubbles (while holding syringe upright) until blood hits the top of cap.
4. Label sample with patient's name, ID number and DOB.

Capillary Samples:
1. The following are recommended sampling sites: earlobe, finger tip, big toe, heel. The heel and big toe are more suitable for use on neonates and infants.
2. Warm the area or puncture site for 5 to 10 minutes prior to actual sampling. This accelerates flow for blood to be representative of general status of patient.
3. Make a puncture using a lancet or similar device. Do not squeeze the area to avoid tissue juice from mixing into blood sample.
4. Wipe off the first drop of blood. Take the sample from the center of the second drop of blood and hold the capillary at a slightly downward angle for an uninterrupted blood flow. Avoid getting air bubbles in the specimen.
5. Refrain from squeezing or milking the puncture site as this may result in faulty measurements or cause hemolysis of blood sample and cause elevated K+ readings.
6. Apply accompanying caps to both ends of the capillary tube and mix the sample with the heparin immediately after collection to prevent blood from clotting. The manufacturer recommends the use of a mixing wire and magnet for capillary samples.
7. Label sample with patient's name, ID and DOB.

Deliver samples immediately to lab for testing. Samples delivered to the lab > 30 minutes after collection may yield erroneous results.

Collect

Plastic blood gas syringe containing approximately 70 IU dry heparin in a 3 mL syringe or 23 IU in a 1 mL syringe - or a capillary tube coated with 70 IU heparin (Radiometer Clinitube).

Amount to Collect

3 mL blood

Sample Type

Heparinized whole blood

Preferred Volume

3 mL blood

Minimum Volume

1 mL blood

Unacceptable Conditions

Samples submitted > 30 min after collection. Samples with needle attached, containing large bubbles, unlabeled, mislabeled, clotted or of insufficient volume for testing.

Units

mmHg, mmol/L, %

Reference Interval

Analyte	Arterial	Venous	Mixed and central venous	Cord blood umbilical artery	Cord blood umbilical vein	Capillary
pH	7.35-7.45	7.29-7.41	7.32-7.42	7.14-7.42	7.22-7.44	0-3 days, 7.31-7.47; >3 days, 7.35-7.45
pCO2 (mmHg)	<1year: 27-41; >=1 year: 32-46	37-65	37-51	34-78	30-63	0-3 days, 29-49; >3 days, 32-46
pO2 (mmHg)	<30 days: 80-100; >=30 days: 83-108	Not applicable	Not applicable	<41	12-43	0-3 days: 33-61; 4-29 days:80-100; >=30 days: 83-108
HCO3- (mmol/L)	23-29	23-31	23-29	21-29	20-28	23-29
Base Excess (BE) (mmol/L)	-3 to 3	Not applicable	-3 to 3	-7 to 3	-6 to 2	-3 to 3
Oxygen saturation (SaO2)	95-100%	Not applicable	Mixed venous: 75-84%; central venous: 67-82%	<81%	23-94%	95-100%

Arterial reference ranges for pH and pO2 adopted from the UCSF reference range previously used with the ABL 835 blood gas analyzers.

Arterial reference range for base excess and oxygen saturation adopted from Klaestrup et al, 2011, Clin Chem Lab Med, 49(9): 1495-1500 using the ABL 837 and 725 blood gas analyzers. Arterial reference range for pCO2 (adult) and bicarbonate was adopted from Klaestrup et al, with modifications made for the ABL 90 Flex Plus analyzers. Pediatric arterial reference range for pCO2 adopted from Radiometer “Acute Care Testing Handbook,” 2014.

Venous reference ranges for pH and bicarbonate were adopted from Ress KL et al, Pathology, 2018, volume 50, supplement page S94. Venous reference ranges for pCO2 were calculated using the Robust method in MedCalc. Reference ranges were verified by running 25 male and 25 female normal volunteers from UCSF Clinical Laboratories.

Note: it is not recommended to use venous blood for assessing oxygenation status.

Critical Values

Arterial:

pH	< 7.20	> 7.55
pCO2	< 25 mmHg	> 65 mmHg
pO2 (patient age <30 days old)	< 40 mmHg	> 100 mmHg
pO2 (patient age ≥30 days old)	< 40 mmHg

Venous:

pH	< 7.20 and > 7.59
pCO2	< 20 and > 75 mm Hg

Mixed Venous:

pH	< 7.20 and > 7.59
pCO2	< 20 and > 65 mm Hg

Central Venous:

pH	< 7.20 and > 7.55
pCO2	< 20 and > 65 mm Hg

Capillary (Parnassus only):

pH	< 7.20	> 7.55
pCO2	< 25 mmHg	> 65 mm Hg

Capillary (Mission Bay and Mount Zion):

pH	< 7.20 and > 7.55
pCO2	< 25 and > 65 mmHg
pO2	0-3 days: < 33 mmHg >= 4 days: < 40 mmHg < 30 days: > 100 mmHg

Cord Blood*:

pH	< 7.0
Base excess	< -10

* Only called to ICN

Synonyms

pH
pCO2
pO2
O2 Saturation
O2 Sat
Base excess
A-a gradient
HCO3-
ABG
BG
BE
oxygen
carbon dioxide
bicarbonate
MVBGO
CVBGO
CAPBGO
CORBGA
CORBGV
ABGCOX
VBGCOX
CVBGCX
ARTBGL
VENBGL
CVBGL
MVBGL
CAPBG
MVBGCX
CIRBGA
CIRBGV

Stability (from collection to initiation)

30 min.

Reported

10 min

Additional Information

This panel includes the following:

pH (PH37), pCO2 (PCO2), pO2 (PO2), Base excess (BEX), Bicarb (HCO3) and oxygen saturation (SAO2)

All reported values are corrected to 37C unless otherwise specified. Results beyond the linear range of the instrument will be reported as < or > the extreme of the linear range. Samples containing small bubbles may be run at the laboratory's discretion. If analyzed, a comment will be added to the result regarding the presence of bubbles in the sample.