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Equipment practice questions

28 questions from the phlebotomy technician practice test.

Equipment practice test

10 questions, graded as you go, with the reason for every answer. No sign-up.

What this covers

Sample questions

Which needle gauge is the usual choice for routine adult venipuncture with an evacuated tube system?

  1. 16 gauge
  2. 25 gauge
  3. 21 gauge
  4. 27 gauge
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C. 21 gauge

A 21-gauge needle gives good flow without undue damage to the vein and is the standard for routine adult draws. A 16-gauge needle is used for blood donation, and very fine needles slow the flow and can damage red cells.

Reference: Venipuncture equipment: needle selection

A phlebotomist chooses a winged infusion (butterfly) set for an elderly patient with small, fragile hand veins. Which gauge is most commonly used?

  1. 23 gauge
  2. 18 gauge
  3. 20 gauge
  4. 16 gauge
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A. 23 gauge

A 23-gauge winged set is the usual choice for small or fragile veins because it is gentle on the vessel while still allowing adequate flow. An 18-gauge or larger needle would be too large for these veins.

Reference: Venipuncture equipment: winged infusion sets

Why is a very small needle, such as 25 gauge, avoided for filling standard evacuated tubes when a larger one can be used?

  1. The tubes will overfill past the fill line
  2. The vein is more likely to form a hematoma
  3. The additive will be drawn back into the vein
  4. Red cells may be damaged, causing hemolysis
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D. Red cells may be damaged, causing hemolysis

Blood forced through a narrow bore by tube vacuum is subject to shear that can rupture red cells, and flow is slow. A small needle makes a smaller hole in the vein, so a hematoma is less likely, not more.

Reference: Preanalytical errors: hemolysis

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