Cleveland HeartLab S, Test

CPT Code: 84295
Order Code: C103
ABN Requirement:  No
Synonyms: Na
Specimen: Serum
Volume: 0.5 mL
Minimum Volume: 0.2 mL
Container: Gel-barrier tube (SST, Tiger Top)



  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 5 times immediately after draw. DO NOT SHAKE.
  3. Allow blood to clot 30 minutes.
  4. Centrifuge at 1300 rcf for 10 minutes.

Transport: Store serum at 2°C to 8°C after collection and ship the same day per packaging instructions provided with the Cleveland HeartLab, Inc. shipping box.


Ambient (15-25°C): 14 days
Refrigerated (2-8°C): 14 days
Frozen (-20°C): >14 days
Deep Frozen (-70°C): >14 days

Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits; hemolyzed or grossly lipemic specimens.

Methodology: Ion Specific Electrode (ISE) test

Turn Around Time: 1 to 3 days

Reference Range:

Age mmol/L
All Ages 136-145

Critical Value:

Age Critical Low, mmol/L Critical High, mmol/L
All Ages ≤120 ≥160

Intended Use: A sodium test may be ordered to monitor electrolyte balance. A sodium test can be used to detect hyponatremia or hypernatremia associated with dehydration, edema, and a variety of diseases.

Limitations: Grossly lipemic specimens cause pseudohyponatremia as a result of fluid displacement.