Which anticoagulant is used in a lavender top tube?

The correct answer is EDTA, as it is the anticoagulant specifically used in lavender top tubes. EDTA, or ethylenediaminetetraacetic acid, is a chelating agent that binds to calcium in the blood, effectively preventing clot formation. This property makes it particularly suitable for hematological studies, where the preservation of the blood cells' morphology and the accurate evaluation of blood cell counts is critical.

When blood is collected into a lavender top tube, the presence of EDTA ensures that the sample remains in a fluid state for testing, allowing laboratories to conduct a complete blood count (CBC) and other related tests without interference from clot formation. This is particularly important because clotted samples can lead to inaccurate results or the need for repeat draws, which can be stressful for both the patient and the practitioner.

The other options refer to different anticoagulants used for other specific purposes. For example, calcium oxalate is typically found in gray top tubes, heparin is used in green top tubes, and citric acid is usually associated with blue top tubes for coagulation studies. Each type of tube is designed for specific tests and appropriate handling of blood specimens, highlighting the importance of using the correct anticoagulant