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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Ammonia

Test Code(s): NH3 / GM2200

CPT Code(s): 82140

Methodology: Glutamate Dehydrogenase

Days Performed: Daily, 24 hours.

Turnaround Time: Stat: 1 hour. All requests processed stat.

Specimen Requirements

Specimen: Blood

Collection Instructions: Fill tube completely.

Collection Container: Preferred: Green top (with Lithium heparin)
Also Acceptable: Green cap with yellow ring (PST)

Collection Volume: Preferred: 4 mL
Pediatrics: 1 mL

Sample Analyzed: Plasma

Volume Required: Preferred: 0.5 mL
Pediatrics: 0.2 mL

Specimen Processing: Centrifuge with cap in place. Redraw specimen if hemolysis is present. Transfer cell-free plasma to plastic vial. Freeze specimen.

Specimen Transport: Transport specimen to laboratory immediately.  Whole blood specimen must arrive in the Core Lab within 30 minutes of collection if not on ice pack.  If in question, transport on ice pack.  Transport frozen plasma on dry ice if coming from outreach location.

Unacceptable Criteria: Hemolyzed specimens are not acceptable. Ice packed specimens greater than 60 minutes old or specimens not on ice pack greater than 30 minutes old when received by laboratory are not acceptable.

Stability: Ambient: 30 minutes
Refrigerated: 2 hours
Frozen: Okay


Reference Interval:
 Age:  umol/L
  15 - 29 days  0-50
  30 days and up  0-40

Critical Calls: View

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