What is the primary purpose of using a tourniquet before IV insertion?

The primary purpose of using a tourniquet before intravenous (IV) insertion is to locate the vein more easily. When a tourniquet is applied to the upper arm, it temporarily restricts venous blood flow while allowing arterial blood to continue to flow into the arm. This results in vein engorgement, making the veins more prominent and easier to visualize and palpate. The visibility and palpability of the veins are crucial for successful cannulation, as it allows the healthcare provider to accurately identify the best site for insertion and reduce the risk of unsuccessful attempts.

Venous structures are deeper and often difficult to locate without the use of a tourniquet, especially in patients with smaller or deeper veins. By enhancing the visibility of veins, the tourniquet serves as an essential tool in the preparation for IV access, thus improving outcomes and efficiency in the procedure.