Platform
Company
Blood Gases
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Currently under review
Pending specialist review and validation.
This test measures the portion of your hemoglobin that is bound to carbon monoxide in a sample of venous blood. Hemoglobin normally carries oxygen, but carbon monoxide attaches to it more strongly, creating carboxyhemoglobin and reducing the blood’s ability to deliver oxygen to your body.
Clinicians use this measurement to assess recent exposure to carbon monoxide from sources such as faulty heaters, vehicle exhaust, house fires, or certain solvents. The result reflects how much carbon monoxide is tied up with your hemoglobin at the time the sample is collected.
Carbon monoxide is a colorless, odorless gas that can cause headache, dizziness, nausea, confusion, chest pain, and in severe cases loss of consciousness. Because it prevents oxygen from reaching organs like the brain and heart, timely recognition is important. This test helps confirm exposure and guides treatment decisions, including the need for oxygen therapy.
Your clinician may order this test if you have symptoms after potential exposure, if you are a smoker with unexplained complaints, after a fire or smoke inhalation, or to monitor your response to treatment. It can also help evaluate workplace or environmental safety concerns when carbon monoxide exposure is suspected.
Higher results generally indicate more carbon monoxide attached to hemoglobin and a greater impact on oxygen delivery. The meaning of a result depends on your symptoms, how long it has been since exposure, whether you received oxygen before the test, and your personal risk factors. People who smoke often have higher baseline values, which your clinician will consider.
If your result suggests significant exposure, your clinician will likely remove you from the source, provide oxygen, and monitor for complications. In some cases, specialized therapy may be considered. Repeat testing can show how levels change with time and treatment. Always seek urgent care if you develop severe symptoms or if others around you have similar symptoms in the same environment.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Levels can fall as you breathe clean air or receive oxygen, so a sample taken later may appear lower than one taken soon after exposure. Tell your clinician when the exposure occurred.
Breathing supplemental oxygen before your blood draw speeds removal of carbon monoxide from hemoglobin and can reduce the measured level. Let the team know if you used oxygen or were treated by first responders.
People who smoke, vape heated tobacco, or have heavy secondhand smoke exposure often have higher baseline carboxyhemoglobin. Your smoking status helps interpret the result.
Some paint strippers and solvents contain methylene chloride, which your body can convert to carbon monoxide. Exposure may raise measurements even without obvious smoke inhalation.
Venous and arterial values are typically similar for carboxyhemoglobin when measured by laboratory co-oximetry. Properly filled, sealed tubes and prompt analysis help ensure accuracy.
Anemia, heart or lung disease, pregnancy, and young age can increase vulnerability to carbon monoxide’s effects, so the same result may have different clinical significance across individuals.
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