When is the lavender top tube primarily used?

The lavender top tube is primarily used for hematology tests, particularly complete blood counts (CBC). This specific tube contains EDTA, an anticoagulant that prevents blood from clotting. The use of EDTA is critical in these types of tests because it allows for the accurate analysis of blood cells, including red blood cells, white blood cells, and platelets, by preserving the cellular components in their native state.

When performing a CBC, it is essential to use a tube that does not promote clotting or alter the cellular composition of the blood sample. The lavender top tube's design meets these needs, making it the standard choice for hematology laboratories.