Anticoagulant used in coagulation study is?
**Core Concept**
The question is testing the knowledge of anticoagulants used in coagulation studies. The underlying principle is to prevent blood clotting in vitro, allowing for accurate measurement of coagulation parameters.
**Why the Correct Answer is Right**
The correct answer is Citrate, which is a commonly used anticoagulant in coagulation studies. Citrate works by chelating calcium ions, which are essential for the coagulation cascade. By binding to calcium, citrate inhibits the activation of prothrombin and other coagulation factors, thereby preventing blood clotting. This allows for the accurate measurement of coagulation parameters, such as prothrombin time (PT) and activated partial thromboplastin time (aPTT).
**Why Each Wrong Option is Incorrect**
**Option A:** Heparin is a strong anticoagulant, but it is not typically used in coagulation studies due to its potential to activate platelets and cause bleeding.
**Option B:** EDTA (ethylenediaminetetraacetic acid) is a chelating agent that can also inhibit coagulation, but it is not the preferred choice for coagulation studies due to its potential to interfere with other laboratory tests.
**Option C:** Oxalate is another chelating agent that can inhibit coagulation, but it is not commonly used in coagulation studies due to its potential to interfere with calcium-dependent assays.
**Clinical Pearl / High-Yield Fact**
When performing coagulation studies, it is essential to use a consistent and reliable anticoagulant, such as citrate, to prevent variability in results. Citrate is widely used in clinical laboratories due to its effectiveness and safety profile.
**Correct Answer:** C. Citrate.