When collecting multiple tubes of blood, when should a technician release the tourniquet?

The correct timing for releasing the tourniquet is within one minute of its application. This practice is essential because prolonged application of the tourniquet can lead to hemoconcentration, which can artificially elevate the levels of certain blood components. Maintaining a strict timeline helps ensure that the blood sample is representative of the patient’s actual state, preventing any skewed results due to the prolonged constriction of blood flow.

Releasing the tourniquet too early, such as immediately after the first tube is filled or as soon as blood starts to flow, can prevent sufficient blood being drawn, particularly if multiple tubes are needed. Waiting for longer than one minute can risk the quality of the samples collected, hence why the emphasis is on releasing it within that timeframe. This practice aligns with standard protocols for phlebotomy to ensure accurate and reliable laboratory results.