Test Code AMM.1 AMMONIA
Methodology
Colorimetric
Useful for assisting in diagnosis of impending or existing hepatic coma, investigating inborn errors of metabolism, and evaluating patients with advanced liver disease.
Specimen Requirements
Specimen must be centrifuged and plasma removed from cells within 20 minutes of draw.
Preferred:
Container/Tube: Green-top (lithium heparin) tube
Specimen Volume: Full tube
Collection Instructions:
- Fill tube completely.
- Immediately place specimen on WET ICE.
If there is a delay in transport of >20 minutes, spin down, separate plasma from cells, and send 1 mL (minimum volume: 0.5 mL) of plasma frozen in plastic vial.
Alternate:
Container/Tube: Lavender-top (ETDA) tube
Specimen Volume: Full Tube
Collection Instructions:
- Fill tube(s) completely.
- Immediately place specimen on WET ICE.
If there is a delay in transport of >20 minutes, spin down, separate plasma from cells, and send 1 mL (minimum volume: 0.5 mL) of plasma frozen in plastic vial.
Day(s) Test Set Up
Monday through Sunday
Reference Values
9-30 µmol/L
Critical value (automatic call-back): >100 µmol/L
Performing Laboratory
Logan Health Medical Center-Chemistry
Test Classification and CPT Coding
82140
Specimen Transport Temperature
On wet ice