Blood Collection Equipment & Supplies Flashcards

Which tube color indicates the presence of EDTA as an additive?

Answer: Lavender/Purple

Lavender/purple-top tubes contain EDTA (ethylenediaminetetraacetic acid), an anticoagulant used for hematology tests such as the CBC.

What is the primary purpose of yellow-top tubes containing sodium polyanethol sulfonate (SPS)?

Answer: Blood cultures

Yellow SPS tubes are used for blood culture collections because SPS inhibits complement, phagocytosis, and certain antibiotics that could interfere with microbial growth.

Which needle gauge is most commonly used for routine adult venipuncture?

Answer: 20–21 gauge

20–21 gauge needles are standard for routine adult venipuncture, providing adequate blood flow while minimizing patient discomfort and hemolysis.

The green-top tube contains which anticoagulant?

Answer: Heparin

Green-top tubes contain heparin (sodium, lithium, or ammonium form), which prevents clotting by inhibiting thrombin activity.

How many times should an EDTA tube be inverted after blood collection to ensure proper mixing?

Answer: 8–10 times

EDTA tubes should be inverted 8–10 times to ensure complete mixing of the anticoagulant with the blood and prevent microclot formation.

Which collection device is BEST suited for patients with fragile, small, or difficult veins?

Answer: Butterfly (winged infusion) set

Butterfly (winged infusion) sets allow more flexible positioning, a shallower insertion angle, and gentler blood collection, making them ideal for fragile or difficult veins.

Which tube color is used for prothrombin time (PT) and partial thromboplastin time (PTT) testing?

Answer: Light blue

Light blue-top tubes contain sodium citrate at a 9:1 blood-to-additive ratio, which is required for accurate coagulation studies including PT and PTT.