Carboxyhemoglobin

Test Code

COHB

Alias/See Also

Carbon Monoxide

CPT Codes
82375

Preferred Specimen

Lithium Heparin Whole Blood (green top tube)

Arterial or venous collections

Minimum Volume

1 mL

Other Acceptable Specimens

EDTA whole blood (purple top tube) on ice

Transport Container

Whole blood: heparinzed syringe or green top tube on slush ice

Transport Temperature

On slushed ice or refrigerated

Specimen Stability

Analyze within 14 days of collection

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

Clotted samples, frozen

Methodology
Hemoximetry

Setup Schedule

Performed daily upon receipt

Report Available

Upon completion of analysis

Reference Range

Non-smokers: <1.5% of tHb

Smokers: 1.5 - 5.0% of tHb

Heavy Smokers: 5.0 - 9.0% of tHb

Clinical Significance

FCOHb is the fraction of carboxyhemoglobin of the total amount of hemoglobin. It carries CO instead of O2, thereby blocking the capability of releasing oxygen to the tissue. CO’s affinity to Hb is 210 times higher than that of O2. CO comes from e.g. exhaust gases and tobacco smoke.

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.