Which additive is preferred for clotting studies to minimize carryover?

Sodium citrate is the preferred additive for clotting studies primarily because it effectively prevents the coagulation of blood by binding calcium ions, which are essential for the clotting process. This property makes sodium citrate the standard choice for tests that assess how well and how quickly blood clots, such as prothrombin time (PT) and activated partial thromboplastin time (aPTT).

Moreover, sodium citrate minimizes carryover effects in laboratory testing. Carryover can occur when the additive from one sample contaminates another, potentially skewing results. Compared to other additives, sodium citrate’s specific interaction with clotting factors allows for accurate and reliable results in coagulation studies while minimizing the risk of interfering with subsequent tests.

In contrast, other anticoagulants like EDTA and potassium oxalate could complicate coagulation studies. EDTA is typically used for hematological analyses and may bind to calcium in a manner that disrupts coagulation testing. Potassium oxalate is primarily used in glucose and other chemistry tests, and while effective in those contexts, it interferes with some clotting assays. Sodium heparin is used in various laboratory tests, but it is not as optimal as sodium citrate for routine coagulation testing because it can affect the