What is a common test performed using a light blue topped tube?

The light blue topped tube is commonly used for tests that require plasma or whole blood for coagulation studies. The Partial Thromboplastin Time (PTT) test specifically is designed to assess the intrinsic pathway of the coagulation cascade, which is crucial for diagnosing bleeding disorders and monitoring patients on anticoagulation therapy.

In the context of how specimens are collected and utilized, the light blue tube contains sodium citrate, which acts as an anticoagulant. This is important because it helps preserve the sample and ensures accurate measurement of clotting factors by preventing the blood from clotting before the test is performed.

Other tests mentioned, such as the Basic Metabolic Panel and Comprehensive Metabolic Panel, typically use gold or green topped tubes as these are designed for serum collection, requiring the blood to clot first before the serum is separated. The Arterial Blood Gas testing usually requires specific heparinized syringes to prevent clotting, making the light blue tube unsuitable for this particular purpose as well.