Why is it important to minimize the time a tourniquet is in place during phlebotomy?

Minimizing the time a tourniquet is in place during phlebotomy is crucial primarily because it helps to prevent hemoconcentration. When a tourniquet is applied, it restricts blood flow in the veins below the site of application, which can cause the blood components to become concentrated in the vascular space. This increased concentration can lead to inaccurate laboratory results, as the levels of certain substances may appear artificially elevated. For instance, proteins, enzymes, and other solutes may become concentrated, skewing the results of tests that rely on accurate serum or plasma levels.

While reducing patient discomfort, facilitating faster blood collection, and ensuring accurate test results are also important considerations in the phlebotomy procedure, the primary concern when it comes to the duration of tourniquet application directly relates to hemoconcentration and its potential impact on laboratory accuracy. Therefore, keeping the tourniquet on for the shortest time necessary is essential for obtaining reliable test results.