Collect

Specimen must be collected from a stasis-free vein of a fasting patient. Smoking should also be avoided before specimen collection. EDTA plasma must be free from hemolysis.

Requirements for patient drawn off site:
  • Draw one 4 mL Lavender EDTA and immediately place on ice. Keep specimen tightly stoppered.
  • Centrifuge immediately and remove plasma. 
  • Place plasma into transport tube and tightly stopper.
  • Freeze immediately. Critical Frozen.

Pediatric Collection

NICU minimum: 0.5 mL Microtainer Lavender EDTA whole blood

Unacceptable Conditions

Hemolyzed specimens and serum.

Storage/Transport Temperature

1mL plasma tightly stoppered. Freeze immediately. CRITICAL FROZEN.

Stability (from collection to initiation)

Lavender EDTA on ice must be tested within 20-30 minutes.
Frozen seperated EDTA plasma stable for several days.

Performed

Daily

Notes

Testing performed at Methodist Pathology Center Core Lab.

Performed

Daily

Methodology

Enzymatic

Reference Interval

0D - 15D 21 - 110 umol/L
15D - 150Y 10 - 36 umol/L

CPT Codes

82140

Test Build Information

OrderCode OrderName ResultCode ResultName ResultUnits LOINC CPT
AMMPL AMMONIA, PLASMA AMMR Ammonia umol/L 16362-6 82140

Example Report

Collection

Collect

Specimen must be collected from a stasis-free vein of a fasting patient. Smoking should also be avoided before specimen collection. EDTA plasma must be free from hemolysis.

Requirements for patient drawn off site:
  • Draw one 4 mL Lavender EDTA and immediately place on ice. Keep specimen tightly stoppered.
  • Centrifuge immediately and remove plasma. 
  • Place plasma into transport tube and tightly stopper.
  • Freeze immediately. Critical Frozen.

Pediatric Collection

NICU minimum: 0.5 mL Microtainer Lavender EDTA whole blood

Unacceptable Conditions

Hemolyzed specimens and serum.

Storage/Transport Temperature

1mL plasma tightly stoppered. Freeze immediately. CRITICAL FROZEN.

Stability (from collection to initiation)

Lavender EDTA on ice must be tested within 20-30 minutes.
Frozen seperated EDTA plasma stable for several days.

Performed

Daily

Notes

Testing performed at Methodist Pathology Center Core Lab.
Ordering

Performed

Daily

Methodology

Enzymatic
Result Interpretation

Reference Interval

0D - 15D 21 - 110 umol/L
15D - 150Y 10 - 36 umol/L
Administrative

CPT Codes

82140
RPS Interface Information

Test Build Information

OrderCode OrderName ResultCode ResultName ResultUnits LOINC CPT
AMMPL AMMONIA, PLASMA AMMR Ammonia umol/L 16362-6 82140

Example Report