What is the primary additive in the Light Blue Tube Top that aids in coagulation testing?

The primary additive in the Light Blue Tube Top is Sodium Citrate, which plays a crucial role in coagulation testing. Sodium Citrate acts as an anticoagulant by binding calcium ions in the blood. Calcium is essential for the coagulation process, and by chelating it, Sodium Citrate effectively prevents the blood from clotting. This property makes it particularly useful for tests such as prothrombin time (PT) and activated partial thromboplastin time (aPTT), both of which are vital for assessing the coagulation pathway.

In coagulation testing, maintaining the sample in a non-clotting state is paramount to obtaining accurate results, and the use of Sodium Citrate in the Light Blue Tube facilitates this. The specific ratio of anticoagulant to blood is critical to ensure proper test results, further highlighting the importance of this additive in coagulation studies.