Ammonia

SIM

10280 

CPT

82140 

Synonyms

NH3, 4 

Specimen Type

Plasma 

Container

Green - Lithium Heparin plasma 

Lavender -  EDTA plasma

Collection Instructions

Centrifuge within 30 minutes of collection.  Do not remove stopper, test must be performed on an unopened tube. (unless removing EDTA plasma for refrigerated storage)
 

Volume

Max: 2 ml plasma 
Min: 0.5 ml

Additional Information

None

Patient Preparation

None

Specimen Processing Instructions

Plasma:  Centrifuge at 3380 rpm’s (±100) for a minimum of 10 minutes within 30 minutes of collection.
Do not remove stopper. Test must be performed on an unopened tube.  (unless EDTA plasma has been separated and refrigerated, see sample stability below.)
 

Transport Requirements

Inpatient- On Ice, deliver STAT to Specimen Processing. 

For outpatient areas, EDTA tubes must be spun and plasma will be separated/refrigerated. 

Specimen Stability

Lithium Heparin plasma- Test must be performed immediately, within 30 minutes after collection 

EDTA plasma  2-8 C  (3 hours)

Rejection Criteria

•Specimen not received in the lab within 30 minutes after 
  collection in Lithium Heparin tube.
•Grossly hemolyzed samples are rejected. 
•Specimen tube that has been opened or aliquoted if not refrigerated.

Reference Range

18-53 umol/L

Critical Value

None 

Test Includes

Ammonia 

Methodology

Timed endpoint method 

Testing Frequency

Performed STAT, Daily, Monday - Sunday 

Reviewed By

Summer Brochu

Reviewed Date

3/7/2022

Supplemental