Ammonia

Message

Chemistry

Test Code

LAB47

Alias/See Also

NH3

CPT Codes
82140

Includes

Ammonia

Preferred Specimen

Light green top tube (lithium heparin plasma)
FULL TUBE, ON ICE; DELIVER TO CHEMISTRY
IMMEDIATELY.

Minimum Volume

Whole blood: 600 uL (one full light-green-top microtainer or two full red-top microtainers).

Serum/plasma: 300 uL plasma.

Other Acceptable Specimens

Serum should not be used for ammonia measurements because ammonia is produced during the clotting process.

Instructions

LAB: Collect specimen and keep on ice. Separate and remove plasma from the cells within 15 minutes of collection in cold centrifuge, deliver to Chemistry and ANALYZE PROMPTLY. DO NOT remove stopper/cap.

If not analyzed immediately, refrigerate for up to three hours or frozen up to 24 hours.

Note: Serum should not be used for ammonia measurements because ammonia is produced during the clotting process.

Transport Temperature

On ice

Specimen Stability

Keep specimen on ice
Ambient: Not recommended.
Referigerated: 3 hours
Frozen: 24 hours

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Hemolyzed, contaminated, not enough volume, Not on ice.

FDA Status
Approved

Setup Schedule

Everyday

Report Available

Same day

Limitations

Glucose at 600 mg/dL (33.3 mmol/L) can cause a decrease of 8 to 40 μmol/L in ammonia concentration

Reference Range

9 - 30 umol/L

Performing Laboratory
Hoag Newport/ Hoag Irvine

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.