CMLA Specimen Collection & Processing

Question 1

What is the correct order of draw when collecting multiple blood tubes using a vacutainer system?

Accepted Answer

Blood cultures → light blue → red/SST → green → lavender → gray

Answer

Lavender → light blue → red/SST → green → blood cultures → gray

Answer

Red/SST → light blue → blood cultures → lavender → green → gray

Answer

Light blue → blood cultures → green → lavender → red/SST → gray

Question 2

Which evacuated tube color is used for coagulation studies such as PT and aPTT?

Accepted Answer

Light blue (sodium citrate)

Answer

Lavender (EDTA)

Answer

Green (heparin)

Answer

Gold/SST (clot activator)

Question 3

At what angle should the needle be inserted when performing a standard venipuncture?

Accepted Answer

15–30 degrees

Answer

5–10 degrees

Answer

45–60 degrees

Answer

70–90 degrees

Question 4

How long should a tourniquet remain applied during blood collection to prevent hemoconcentration?

Accepted Answer

No more than 1 minute

Answer

2–3 minutes

Answer

Up to 5 minutes

Answer

As long as needed to locate the vein

Question 5

Which additive is found in lavender (purple) top tubes and is used for most hematology testing?

Accepted Answer

EDTA (ethylenediaminetetraacetic acid)

Answer

Sodium citrate

Answer

Sodium fluoride

Answer

Lithium heparin

Question 6

What is the proper procedure for labeling a blood specimen?

Accepted Answer

Label the tube at the patient's side immediately after collection, verifying the patient's identity

Answer

Label the tube before leaving the patient's room to save time

Answer

Label the tube upon arrival at the laboratory to prevent smearing

Answer

Allow the patient to write their own name on the label for accuracy

Question 7

Which tube color contains thrombin or clot activator plus a gel barrier and is used for serum chemistry testing?

Accepted Answer

Gold or SST (serum separator tube)

Answer

Light blue

Answer

Lavender

Answer

Gray