Ammonia
Label Mnemonic: | PNH3 |
Epic code: | LAB47 |
Downtime form: | A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery |
Chemistry
6240 RCP
356-3527
6240 RCP
356-3527
Specimen(s):
Plasma
Collection Medium:
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Lavender top tube 3 mL (EDTA) |
Alternate
Collection Media:
Heelstick specimens are highly discouraged due to risk of artifactually elevated ammonia levels. or Call laboratory for additional acceptable specimen collection containers.
Minimum:
Full 3 mL lavender top (EDTA) tube or ONE lavender top (EDTA)
microtube for pediatric patients.
Rejection Criteria:
Syringe is not acceptable.
Delivery Instructions:

Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around
Time:
1 hour (upon receipt in laboratory)
Reference Range:
Birth to 48 hours old: 64-107 μmol/L
2 days old to 30 days old: 56-92 μmol/L
1 month to 18 years: 21-50 μmol/L
Male: 11-51 μmol/L
Female: 16-60 μmol/L
Clinically significant: >150 μmol/L (<18 years old only)
2 days old to 30 days old: 56-92 μmol/L
1 month to 18 years: 21-50 μmol/L
Male: 11-51 μmol/L
Female: 16-60 μmol/L
Clinically significant: >150 μmol/L (<18 years old only)
Comments:
This test is also performed in the Iowa
River Landing (IRL) clinical laboratory (for specimens drawn at that
site).
Test
Limitations:
Criterion: recovery within plus or minus 10% of initial values Icterus: No interference up to an I index of 30 (approximate conjugated and unconjugated bilirubin concentration: 30 mg/dL). Hemolysis: No interference up to an H index of 200 (approximate hemoglobin concentration: 200 mg/dL). Lipemia (Intralipid): No interference up to an L index of 150. There is poor correlation between turbidity and triglycerides concentration. Absorbance flagging may also be observed as a result of an absorbance increase.
Methodology:
Enzymatic
CPT Code:
82140
See Additional Information:
Specimens Requiring Immediate Delivery
Specimens Requiring Immediate Delivery