Carbon Dioxide, Bicarbonate (CO2)

Cleveland Heartlab C, Test

CPT Code: 82374
Order Code: C105
ABN Requirement:  No
Synonyms: CO₂; TCO₂; Bicarbonate
Volume: 0.5 mL
Minimum Volume: 0.2 mL
Specimen: Serum
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 for 10 minutes.

Special Instructions: Submit samples in tightly capped tubes.

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


Ambient (15-25°C): 40 hours
Refrigerated (2-8°C): 7 days
Frozen (-20°C): 6 months
Deep frozen (-70°C): 6 months

Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits

Methodology: Photometric

Turn Around Time: 1 to 3 days

Reference Range:

Age mmol/L
All Ages 21-33

Clinical Significance: Total carbon dioxide may be measured to identify electrolyte imbalances in individuals with acute or chronic illnesses.

Limitations: Bicarbonate content in serum or plasma stored in uncapped tubes decreases approximately 4 mmol/L after one hour. In very rare cases, gammopathy may cause unreliable results.

The CPT codes provided 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 payer being billed.