Which vacutainer additive is known to cause the most carryover issues in laboratory testing?

The additive that is known to cause the most carryover issues in laboratory testing is EDTA (Ethylenediaminetetraacetic acid). EDTA is a chelating agent commonly used as an anticoagulant in blood collection tubes. Its primary function is to bind calcium ions, which are crucial for the clotting process. However, its ability to complex with metal ions can lead to contamination of other tests, particularly those that rely on metal ion concentration, such as trace element analysis or certain biochemical assays.

When there is carryover from EDTA tubes, it can interfere with assays that are sensitive to changes in metal ion concentrations or that involve enzymatic reactions that depend on specific ions present in the sample. This contamination can result in inaccurate test results, making it imperative for laboratories to employ proper protocols to mitigate these carryover effects, such as using appropriate wash techniques or utilizing dedicated equipment.

The other additives, such as lithium heparin, sodium citrate, and sodium heparin, can also cause carryover issues, but to a lesser extent than EDTA. Each of these additives has its own specific roles and potential interactions, but EDTA stands out for its broad potential to affect various assay outcomes due to its chelating properties