What is the purpose of a tourniquet during venipuncture?

The purpose of a tourniquet during venipuncture is to engorge the veins and make them more visible. When a tourniquet is applied above the venipuncture site, it restricts blood flow from the arm, causing the veins to swell with blood. This engorgement enhances the visibility and palpability of the veins, making it easier for the phlebotomist to locate the optimal site for needle insertion. By promoting better vein distension, the tourniquet aids in facilitating a successful venipuncture procedure, which ultimately contributes to accurate blood sample collection.

The other options focus on various aspects of phlebotomy that are separate from the primary role of the tourniquet. For instance, disinfecting the skin is essential for preventing infection, stabilizing the patient's arm ensures safety during the procedure, and minimizing pain during needle insertion is important for patient comfort, but these functions are not achieved by the use of a tourniquet.