What is the primary anticoagulant found in a light blue top tube?

The primary anticoagulant found in a light blue top tube is sodium citrate. This specific anticoagulant functions by binding calcium ions in the blood, which are essential for the coagulation process. By chelating calcium, sodium citrate effectively prevents blood from clotting, allowing for the accurate measurement of coagulation factors in tests such as PT (Prothrombin Time) and aPTT (Activated Partial Thromboplastin Time).

This mechanism is crucial for laboratories that need precise results in clotting studies, making the light blue top tube a standard choice for these tests. Sodium citrate is typically used at a 3.2% concentration in these tubes, ensuring optimal performance and accurate diagnostic results in various clinical settings.