What is the maximum time that a tourniquet should be applied when drawing blood?

The maximum time that a tourniquet should be applied when drawing blood is no more than one minute. This recommendation is based on the need to minimize the likelihood of complications such as hemoconcentration, which can lead to inaccurate test results. When a tourniquet is applied for too long, it can cause blood to pool in the veins, increasing the concentration of cellular components and proteins in the blood sample, and potentially altering the results of certain tests.

The one-minute guideline helps ensure that blood flow is restricted just enough to make veins more prominent for easier access while preventing the adverse effects associated with prolonged application. It's also essential for maintaining patient comfort and safety during the blood draw process.