EDTA salts (ethylenediaminetetraacetic acid) are used to anticoagulate whole blood for haematological investigations as the cellular components of the blood are particularly well preserved by EDTA. It works as an anticoagulant as it forms complexes with metal ions such as calcium, therefore inhibiting the coagulation cascade. Anticoagulation with EDTA is irreversible.
The EDTA concentration in BD Vacutainer® Tubes is 1.8 mg per mL of complete blood when the fill level is correct, as recommended by the ICSH (International Council Society of Haematology). The ICSH recommends dipotassium EDTA salt (K2 EDTA) for haematological investigation. BD Vacutainer® plastic tubes are available with spray dried K2 EDTA
Mixing the Tube
Correct mixing (8-10 inversions) of the EDTA tube immediately after the blood sample has been taken is extremely important to avoid microclotting