What is the preferred container for carbon monoxide hemoglobin testing?

The preferred container for carbon monoxide hemoglobin testing is an EDTA or purple top tube. This choice is correct because EDTA acts as an anticoagulant, which preserves the blood sample by preventing clotting and maintaining the integrity of the hemoglobin. Carbon monoxide binds to hemoglobin, creating carboxyhemoglobin, and accurate measurement of this compound is critical for diagnosing carbon monoxide exposure. Using an EDTA tube ensures that the sample remains in its native state, allowing for reliable test results.

Other containers, such as the sodium citrate or light blue top, are typically used for coagulation studies and may not adequately preserve the sample integrity for carboxyhemoglobin testing. Similarly, while serum separator tubes or red top tubes are commonly used for serum testing, they allow for clot formation, which can affect the accuracy of the measurements. The NaF or grey top is generally used for glucose testing due to its ability to inhibit glycolysis but is not suitable for carbon monoxide testing. Thus, the EDTA purple top is specifically chosen for its compatibility with the requirements of measuring carboxyhemoglobin levels accurately.