What is the main purpose of the lavender tube top during blood collection?

The main purpose of the lavender tube cap during blood collection is associated with whole blood collections. Lavender-top tubes typically contain anticoagulants, such as ethylenediaminetetraacetic acid (EDTA), which prevent the blood from clotting. This is crucial for tests that require whole blood samples, as it allows for the analysis of cells and plasma without interference from clotting.

These tubes are commonly utilized in hematology tests, such as complete blood counts (CBCs), where the components of blood, including red and white blood cells, are evaluated. The use of a lavender tube cap ensures that the integrity of the blood sample is maintained by preserving the cellular components necessary for accurate testing.

In contrast, blood culture, serum separation, and coagulation studies typically utilize other colored tube tops. Blood cultures generally require sterile technique and different additives, serum separation often involves tubes that are serum separator types, and coagulation studies are usually performed with light blue-top tubes that contain specific anticoagulants for those tests.