Carbon Monoxide

Abbrev Code:CO   
Order Code:LAB3398Order Name:Carbon Monoxide
Synonyms:Carboxyhemoglobin; CO Hb
Methodology:Spectrophotometric analysis of hemolysate
CPT Codes: 82375 x1
Turnaround Time:Performed and reported 24 hours/day.
Special Instructions:Green (lithium heparin, no gel) and Green (sodium heparin, no gel) are acceptable tube types for Outreach and non-Co testing Fairview sites. For in-house testing, a dry heparin syringe is the preferred sample type.

Collection Instructions

Specimen:Whole Blood (arterial, venous, capillary)
Optimal Volume:1 mL
Minimum\Peds Volume:0.5 mL (3 mL syringe); 0.2 mL (tuberculin syringe); 0.1 mL (capillary tube)
Container:St Johns/St Joseph/Woodwinds - Dry heparin syringe, Dry heparin syringe
Alternate Containers: Capillary (lithium heparin) gas tube, Green (lithium heparin, no gel), Green (sodium heparin, no gel), St Johns/St Joseph/Woodwinds-Green (lithium heparin, no gel)
Collection Instructions:Sample should be free of air bubbles. If collecting in green (heparin, no gel), do not remove stopper. Do not process.
Patient Preparation:If carboxyhemoglobin is to be tested to work up smoking and COPD, collect samples as soon after the patient has smoked as possible. If the patient is a smoker or may have occupational exposure (e.g., mechanics), a sample collected in the late afternoon or evening may be more useful than a sample collected in the morning. Moderate levels of CO can be cleared from the blood in hours.
Causes for Rejection:Gross lipemia or the presence of >1% sulfhemoglobin. Samples collected in a gel tube.

Processing and Shipping

Specimen Processing:Do not process. Store at room temperature.
Shipping Instructions:Ship at room temperature or on ice. Must arrive within 72 hours.
Test Performed at or Referral Lab Chemistry  (Range, UMMC-East Bank, Lakes, Ridges, Northland, Southdale, UMMC/UMMCH-West Bank, UMMC West NICU, M Health Clinic and Surgery Center, Grand Itasca, St. Joseph's, St. John's, Woodwinds)


Critical Range:Disturbance of judgment, headache, and dizziness occur at 10-30%; coma at 50-60%; fatality can occur at 60% or more; and rapid death at levels of 80%.
Whole Blood Testing Critical Values and Reference Ranges
Reference Range:
0-1 mo 0-4%
1 mo & older, nonsmokers 0-2%
1 mo & older, smokers 0-10%
Some smokers may have higher levels.
Slight dyspnea may occur with even limited CO2 elevation.
Whole Blood Testing Critical Values and Reference Ranges
Use:Evaluate for suspected toxicity.

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