Which sequence describes the correct order of events for collecting and processing tubes?

Which sequence describes the correct order of events for collecting and processing tubes?

• A. Inversion, then filling.
• B. Filling the tube followed by immediate inversion.
• C. Storing the tube, then inversion.
• D. Inverting after centrifugation.

Answer: (B)

Mixing the blood with the additive right after collection is essential so the additive can interact uniformly with the sample. The correct sequence starts by filling the tube first, then immediately inverting it the required number of times to ensure the additive and blood mix thoroughly. This immediate mixing prevents clotting in anticoagulant tubes or proper clot activation in clot-promoting tubes and sets up the sample for accurate processing. Inverting before filling would not expose the collected blood to the additive, so it wouldn’t be effective. Storing the tube before inversion allows changes like clotting or settling to begin, which can skew results. Inverting after centrifugation misses the chance to mix blood with the additive at the collection stage and is inappropriate for the initial processing steps.

Mixing the blood with the additive right after collection is essential so the additive can interact uniformly with the sample. The correct sequence starts by filling the tube first, then immediately inverting it the required number of times to ensure the additive and blood mix thoroughly. This immediate mixing prevents clotting in anticoagulant tubes or proper clot activation in clot-promoting tubes and sets up the sample for accurate processing.

Inverting before filling would not expose the collected blood to the additive, so it wouldn’t be effective. Storing the tube before inversion allows changes like clotting or settling to begin, which can skew results. Inverting after centrifugation misses the chance to mix blood with the additive at the collection stage and is inappropriate for the initial processing steps.