NHCO Phlebotomy Practice Exam 2
Questions and Answers with Rationales
Top Rated A+
1. Which step should occur immediately before venipuncture after the patient
and equipment have been prepared?
A. Label all tubes away from the patient
B. Cleanse the selected site according to protocol
C. Remove the tourniquet permanently
D. Centrifuge the tubes
Answer: B. Cleanse the selected site according to protocol
Rationale: Once the patient and collection equipment are ready and the site has
been selected, appropriate skin antisepsis is performed before needle insertion. The
site should then be allowed to dry according to the antiseptic's instructions.
2. Which vein is usually preferred because it is relatively well anchored and
located away from major nerves and arteries?
A. Median cubital
B. Basilic
C. Femoral
D. Radial artery
Answer: A. Median cubital
Rationale: The median cubital vein is commonly the first choice for routine
antecubital venipuncture because it is generally stable and accessible.
3. A patient has very small, fragile veins. Which approach is most
appropriate?
,A. Use excessive suction
B. Use appropriate equipment and a gentle technique
C. Probe repeatedly with the needle
D. Apply maximum tourniquet pressure
Answer: B. Use appropriate equipment and a gentle technique
Rationale: Fragile veins can rupture easily. Appropriate needle/device selection,
careful anchoring, and gentle technique reduce trauma.
4. Which tube is generally used for hematology testing such as a CBC?
A. Lavender
B. Light blue
C. Gray
D. Green
Answer: A. Lavender
Rationale: Lavender tubes generally contain EDTA, which preserves cellular
components and is commonly used for CBC and other hematology tests.
5. A phlebotomist notices that the patient's blood is not entering the tube.
What should be done FIRST?
A. Probe aggressively
B. Assess needle and vein position and troubleshoot according to training
C. Increase the tourniquet pressure indefinitely
D. Shake the tube
Answer: B. Assess needle and vein position and troubleshoot according to
training
Rationale: Lack of blood flow may result from needle position, vein collapse, or
equipment problems. The phlebotomist should assess the situation rather than
blindly manipulating the needle.
,6. Which of the following can cause a vein to collapse during evacuated-tube
collection?
A. Excessive vacuum relative to a small or fragile vein
B. Proper tube selection
C. Correct patient identification
D. Proper site cleansing
Answer: A. Excessive vacuum relative to a small or fragile vein
Rationale: A fragile or small vein may collapse when exposed to strong vacuum.
Appropriate equipment selection and technique can help minimize this problem.
7. What is the purpose of a tourniquet during venipuncture?
A. To completely stop circulation
B. To temporarily increase venous prominence
C. To sterilize the arm
D. To prevent all hematomas
Answer: B. To temporarily increase venous prominence
Rationale: The tourniquet temporarily restricts venous return, allowing veins to
become more prominent for collection. It should not significantly obstruct arterial
flow.
8. Which tube commonly contains sodium citrate?
A. Light blue
B. Lavender
C. Green
D. Gray
Answer: A. Light blue
, Rationale: Sodium citrate is the anticoagulant commonly used in light-blue
coagulation tubes. Maintaining the appropriate blood-to-additive ratio is essential.
9. Which test commonly requires a light-blue-top tube?
A. CBC
B. PT/INR
C. Hemoglobin A1c
D. Routine blood culture
Answer: B. PT/INR
Rationale: PT/INR is a coagulation test and is commonly collected in a sodium-
citrate light-blue tube.
10. Why should a phlebotomist avoid drawing blood through an area of
infection?
A. Infection makes blood impossible to collect
B. It can increase patient risk and compromise specimen quality
C. It always causes hemolysis
D. It makes the needle magnetic
Answer: B. It can increase patient risk and compromise specimen quality
Rationale: Inflamed or infected tissue should generally not be selected for
venipuncture. An appropriate alternative site should be used.
11. Which action is appropriate when a patient has an active IV in one arm?
A. Prefer the opposite arm when possible
B. Always draw directly above the IV
C. Stop the IV independently
D. Draw through the infusion without consideration
Answer: A. Prefer the opposite arm when possible
Questions and Answers with Rationales
Top Rated A+
1. Which step should occur immediately before venipuncture after the patient
and equipment have been prepared?
A. Label all tubes away from the patient
B. Cleanse the selected site according to protocol
C. Remove the tourniquet permanently
D. Centrifuge the tubes
Answer: B. Cleanse the selected site according to protocol
Rationale: Once the patient and collection equipment are ready and the site has
been selected, appropriate skin antisepsis is performed before needle insertion. The
site should then be allowed to dry according to the antiseptic's instructions.
2. Which vein is usually preferred because it is relatively well anchored and
located away from major nerves and arteries?
A. Median cubital
B. Basilic
C. Femoral
D. Radial artery
Answer: A. Median cubital
Rationale: The median cubital vein is commonly the first choice for routine
antecubital venipuncture because it is generally stable and accessible.
3. A patient has very small, fragile veins. Which approach is most
appropriate?
,A. Use excessive suction
B. Use appropriate equipment and a gentle technique
C. Probe repeatedly with the needle
D. Apply maximum tourniquet pressure
Answer: B. Use appropriate equipment and a gentle technique
Rationale: Fragile veins can rupture easily. Appropriate needle/device selection,
careful anchoring, and gentle technique reduce trauma.
4. Which tube is generally used for hematology testing such as a CBC?
A. Lavender
B. Light blue
C. Gray
D. Green
Answer: A. Lavender
Rationale: Lavender tubes generally contain EDTA, which preserves cellular
components and is commonly used for CBC and other hematology tests.
5. A phlebotomist notices that the patient's blood is not entering the tube.
What should be done FIRST?
A. Probe aggressively
B. Assess needle and vein position and troubleshoot according to training
C. Increase the tourniquet pressure indefinitely
D. Shake the tube
Answer: B. Assess needle and vein position and troubleshoot according to
training
Rationale: Lack of blood flow may result from needle position, vein collapse, or
equipment problems. The phlebotomist should assess the situation rather than
blindly manipulating the needle.
,6. Which of the following can cause a vein to collapse during evacuated-tube
collection?
A. Excessive vacuum relative to a small or fragile vein
B. Proper tube selection
C. Correct patient identification
D. Proper site cleansing
Answer: A. Excessive vacuum relative to a small or fragile vein
Rationale: A fragile or small vein may collapse when exposed to strong vacuum.
Appropriate equipment selection and technique can help minimize this problem.
7. What is the purpose of a tourniquet during venipuncture?
A. To completely stop circulation
B. To temporarily increase venous prominence
C. To sterilize the arm
D. To prevent all hematomas
Answer: B. To temporarily increase venous prominence
Rationale: The tourniquet temporarily restricts venous return, allowing veins to
become more prominent for collection. It should not significantly obstruct arterial
flow.
8. Which tube commonly contains sodium citrate?
A. Light blue
B. Lavender
C. Green
D. Gray
Answer: A. Light blue
, Rationale: Sodium citrate is the anticoagulant commonly used in light-blue
coagulation tubes. Maintaining the appropriate blood-to-additive ratio is essential.
9. Which test commonly requires a light-blue-top tube?
A. CBC
B. PT/INR
C. Hemoglobin A1c
D. Routine blood culture
Answer: B. PT/INR
Rationale: PT/INR is a coagulation test and is commonly collected in a sodium-
citrate light-blue tube.
10. Why should a phlebotomist avoid drawing blood through an area of
infection?
A. Infection makes blood impossible to collect
B. It can increase patient risk and compromise specimen quality
C. It always causes hemolysis
D. It makes the needle magnetic
Answer: B. It can increase patient risk and compromise specimen quality
Rationale: Inflamed or infected tissue should generally not be selected for
venipuncture. An appropriate alternative site should be used.
11. Which action is appropriate when a patient has an active IV in one arm?
A. Prefer the opposite arm when possible
B. Always draw directly above the IV
C. Stop the IV independently
D. Draw through the infusion without consideration
Answer: A. Prefer the opposite arm when possible
