Final answer:
Heparin is the anticoagulant used in ABG syringes to prevent blood from clotting and ensure accurate measurements during arterial blood gas analysis.
Step-by-step explanation:
The anticoagulant used for ABG (arterial blood gas) syringes is heparin. Heparin is a short-acting anticoagulant that is stored in mast cells and released when tissues are injured. It opposes the conversion of prothrombin (factor II) to thrombin in the common pathway of blood coagulation. Thus, heparin ensures an accurate measurement by preventing the blood sample from clotting. This is crucial for testing as clotted blood cannot be analyzed properly for gases and pH levels. Of the options provided, Heparin would be the correct answer.