PCT NHA EXAM PRACTICE QUESTIONS COMPLETE WITH
100% CORRECT ANSWERS AND DETAILED RATIONALE
1. The lavender-topped tube contains which of the following
additives?
A. No additive
B. SPS
C. Na+ citrate
D. EDTA
Correct Answer: D. EDTA
Rationale: Lavender-topped tubes contain EDTA
(ethylenediaminetetraacetic acid), which is an anticoagulant that binds
calcium and prevents blood clotting by chelating calcium ions. EDTA is
commonly used for hematology studies such as complete blood counts
(CBC).
2. Which additive is found in a gray-topped tube?
A. Na+ citrate
B. EDTA
C. K+ oxalate
D. None of the above
Correct Answer: C. K+ oxalate
Rationale: Gray-topped tubes contain potassium oxalate as an
,anticoagulant and sodium fluoride as a preservative. This combination is
specifically used for glucose testing because the sodium fluoride inhibits
glycolysis, preserving glucose levels in the blood sample.
3. Which needle has the largest gauge?
A. 25 g
B. 20 g
C. 21 g
D. 16 g
Correct Answer: D. 16 g
Rationale: In needle sizing, the smaller the gauge number, the larger the
diameter of the needle. Therefore, a 16-gauge needle has the largest
diameter compared to 20g, 21g, and 25g. 16-gauge needles are
typically used for blood donation or rapid fluid administration.
4. Which gauge needle is typically used for a standard adult
venipuncture?
A. 23 g
B. 25 g
C. 21 g
D. 16 g
Correct Answer: C. 21 g
Rationale: A 21-gauge needle is the standard size for routine adult
venipuncture. It provides a good balance between patient comfort and
adequate blood flow. Needles that are too small (like 23g or 25g) can
,cause hemolysis, while larger needles (like 16g) cause more patient
discomfort.
5. What is the venipuncture equipment that consists of a needle
attached to plastic tubing called?
A. Micro-collection container
B. Syringe
C. Winged infusion set
D. Evacuated tube
Correct Answer: C. Winged infusion set
Rationale: A winged infusion set, commonly known as a "butterfly,"
consists of a small needle attached to flexible plastic tubing with
"wings" that allow for easier manipulation. It is particularly useful for
drawing blood from small or fragile veins and for patients who are
difficult to access.
6. All of the following are true about winged infusion sets EXCEPT:
A. Commonly referred to as a butterfly
B. Used on fragile veins
C. Comes in needle sizes of 16g and 18g
D. Preferred over a syringe
Correct Answer: C. Comes in needle sizes of 16g and 18g
Rationale: Winged infusion sets typically come in smaller gauge sizes
such as 21g, 23g, or 25g, not 16g and 18g. 16g and 18g needles are too
large for the types of veins that butterflies are designed to access. The
other statements are true: butterflies are commonly called butterflies,
, used on fragile veins, and often preferred over syringes for difficult
venipunctures.
7. A patient scheduled for a fasting blood glucose test states that he
took his medications with orange juice this morning. What should the
PCT do next?
A. Draw the patient's blood
B. Tell the patient to call his physician immediately
C. Explain that you cannot draw his blood without speaking to his
physician first
D. Ask the patient to leave and come back tomorrow
Correct Answer: C. Explain that you cannot draw his blood without
speaking to his physician first
Rationale: Fasting blood glucose tests require the patient to have
nothing by mouth except water for 8-12 hours. Orange juice contains
sugar that will affect the test results. The PCT should not draw the blood
for a fasting test and should consult with the physician to determine
whether to proceed with a non-fasting test or reschedule.
8. Which action is incorrect when performing a dermal puncture?
A. Puncturing the plantar surface of the heel
B. Allowing the alcohol to dry prior to puncture
C. Collecting the first drop of blood
D. Using a 2.0 mm lancet on a child
Correct Answer: C. Collecting the first drop of blood
Rationale: The first drop of blood should be wiped away because it may
100% CORRECT ANSWERS AND DETAILED RATIONALE
1. The lavender-topped tube contains which of the following
additives?
A. No additive
B. SPS
C. Na+ citrate
D. EDTA
Correct Answer: D. EDTA
Rationale: Lavender-topped tubes contain EDTA
(ethylenediaminetetraacetic acid), which is an anticoagulant that binds
calcium and prevents blood clotting by chelating calcium ions. EDTA is
commonly used for hematology studies such as complete blood counts
(CBC).
2. Which additive is found in a gray-topped tube?
A. Na+ citrate
B. EDTA
C. K+ oxalate
D. None of the above
Correct Answer: C. K+ oxalate
Rationale: Gray-topped tubes contain potassium oxalate as an
,anticoagulant and sodium fluoride as a preservative. This combination is
specifically used for glucose testing because the sodium fluoride inhibits
glycolysis, preserving glucose levels in the blood sample.
3. Which needle has the largest gauge?
A. 25 g
B. 20 g
C. 21 g
D. 16 g
Correct Answer: D. 16 g
Rationale: In needle sizing, the smaller the gauge number, the larger the
diameter of the needle. Therefore, a 16-gauge needle has the largest
diameter compared to 20g, 21g, and 25g. 16-gauge needles are
typically used for blood donation or rapid fluid administration.
4. Which gauge needle is typically used for a standard adult
venipuncture?
A. 23 g
B. 25 g
C. 21 g
D. 16 g
Correct Answer: C. 21 g
Rationale: A 21-gauge needle is the standard size for routine adult
venipuncture. It provides a good balance between patient comfort and
adequate blood flow. Needles that are too small (like 23g or 25g) can
,cause hemolysis, while larger needles (like 16g) cause more patient
discomfort.
5. What is the venipuncture equipment that consists of a needle
attached to plastic tubing called?
A. Micro-collection container
B. Syringe
C. Winged infusion set
D. Evacuated tube
Correct Answer: C. Winged infusion set
Rationale: A winged infusion set, commonly known as a "butterfly,"
consists of a small needle attached to flexible plastic tubing with
"wings" that allow for easier manipulation. It is particularly useful for
drawing blood from small or fragile veins and for patients who are
difficult to access.
6. All of the following are true about winged infusion sets EXCEPT:
A. Commonly referred to as a butterfly
B. Used on fragile veins
C. Comes in needle sizes of 16g and 18g
D. Preferred over a syringe
Correct Answer: C. Comes in needle sizes of 16g and 18g
Rationale: Winged infusion sets typically come in smaller gauge sizes
such as 21g, 23g, or 25g, not 16g and 18g. 16g and 18g needles are too
large for the types of veins that butterflies are designed to access. The
other statements are true: butterflies are commonly called butterflies,
, used on fragile veins, and often preferred over syringes for difficult
venipunctures.
7. A patient scheduled for a fasting blood glucose test states that he
took his medications with orange juice this morning. What should the
PCT do next?
A. Draw the patient's blood
B. Tell the patient to call his physician immediately
C. Explain that you cannot draw his blood without speaking to his
physician first
D. Ask the patient to leave and come back tomorrow
Correct Answer: C. Explain that you cannot draw his blood without
speaking to his physician first
Rationale: Fasting blood glucose tests require the patient to have
nothing by mouth except water for 8-12 hours. Orange juice contains
sugar that will affect the test results. The PCT should not draw the blood
for a fasting test and should consult with the physician to determine
whether to proceed with a non-fasting test or reschedule.
8. Which action is incorrect when performing a dermal puncture?
A. Puncturing the plantar surface of the heel
B. Allowing the alcohol to dry prior to puncture
C. Collecting the first drop of blood
D. Using a 2.0 mm lancet on a child
Correct Answer: C. Collecting the first drop of blood
Rationale: The first drop of blood should be wiped away because it may
