Phlebotomy Technician Practice Exam (NCPT/CPT)

What is the correct order of draw for a CBC/PTT and chemical Panel when using a wing-tip needle?

1. Red, Light Blue, Lavender

2. Light Blue, SST, Lavender

3. Lavender, Light Blue, SST

4. SST, Light Blue, Lavender

The correct answer is: Light Blue, SST, Lavender

For a CBC/PTT and chemical Panel, the correct order of draw using a wing-tip needle is Light Blue, SST, Lavender. This option ensures that the blood samples collected in the light blue tube, which contains sodium citrate as an anticoagulant, are collected first to prevent contamination from other additives in the other tubes. The second sample collected in the SST tube will help to clot the blood faster and separate the serum from the blood cells. Finally, the lavender tube, which contains EDTA as an anticoagulant, is used to collect the samples for the CBC/PTT test. This will prevent cross-contamination and ensure accurate results. The other options are incorrect because they do not follow the recommended order of draw and may result in incorrect test results. For example, in option A, drawing the lavender tube first may cause the blood to clot, resulting in