Phlebotomy Test Venipuncture Procedures 2 — Questions and Answers
Question 1: Which vein is considered the FIRST choice for routine venipuncture in most patients?
- Cephalic vein
- Median cubital vein (Correct answer)
- Basilic vein
- Median antebrachial vein
Correct answer: Median cubital vein
The median cubital vein is the preferred first choice because it is large, well-anchored, and less painful to puncture.
Question 2: What is the maximum recommended time a tourniquet should remain applied before venipuncture?
- 30 seconds
- 1 minute (Correct answer)
- 2 minutes
- 3 minutes
Correct answer: 1 minute
A tourniquet should not remain in place for more than 1 minute to prevent hemoconcentration and erroneous lab results.
Question 3: A phlebotomist notices the needle bevel is facing downward during insertion. What problem will likely occur?
- Hemolysis of the sample
- Failure to enter the vein or poor blood flow (Correct answer)
- Air bubbles in the tube
- Petechiae at the site
Correct answer: Failure to enter the vein or poor blood flow
The bevel must face upward to allow smooth entry into the vein; a downward bevel causes the needle tip to press against the vein wall, impeding flow.
Question 4: When using an evacuated tube system, which tube should be filled LAST to avoid carryover contamination?
- Red/gold SST
- Lavender EDTA (Correct answer)
- Light blue citrate
- Green heparin
Correct answer: Lavender EDTA
EDTA in the lavender tube can contaminate other tubes and is drawn last among additive tubes to protect coagulation and chemistry results.
Question 5: A patient's arm shows signs of a hematoma forming during blood draw. What is the FIRST action to take?
- Apply more pressure to the tourniquet
- Release the tourniquet and remove the needle immediately (Correct answer)
- Redirect the needle to find the vein
- Continue drawing to complete the collection
Correct answer: Release the tourniquet and remove the needle immediately
A forming hematoma indicates blood is leaking into surrounding tissue; the tourniquet must be released and the needle removed to stop further extravasation.
Question 6: What needle gauge is most commonly used for routine adult venipuncture?
- 18 gauge
- 21 gauge (Correct answer)
- 23 gauge
- 25 gauge
Correct answer: 21 gauge
A 21-gauge needle provides an optimal balance of blood flow rate and patient comfort for routine adult venipuncture.
Question 7: After venipuncture, gauze pressure should be applied for at least how long to ensure hemostasis in a normal patient?
- 30 seconds
- 1–2 minutes (Correct answer)
- 5 minutes
- 10 minutes
Correct answer: 1–2 minutes
Firm pressure for 1–2 minutes is adequate for most patients with normal coagulation to achieve hemostasis at the puncture site.
Phlebotomy Test Venipuncture Procedures 2
Which vein is considered the FIRST choice for routine venipuncture in most patients?