What is one common pre-examination error in hematology related to specimen handling?

In the context of hematology and specimen handling, one common pre-examination error is improper tourniquet technique. The use of a tourniquet is essential for venipuncture as it helps to engorge the veins, making them more prominent and easier to access. However, problems can arise if the tourniquet is left on for too long, which can lead to hemolysis or alter the concentration of certain components in the blood, such as potassium, and may even result in artifacts or erroneous test results. Proper technique involves applying the tourniquet just before the needle insertion and removing it as soon as blood flow is established.

While incorrect labeling of specimens, defective tubes, and insufficient mixing are indeed critical concerns in the pre-examination phase, improper tourniquet technique specifically relates to the immediate action taken during blood collection that can significantly impact the quality of the drawn sample. Thus, understanding the implications of tourniquet use is crucial for ensuring accurate hematological results.