NHCO PHLEBOTOMY EXAM 200 ACTUAL QUESTIONS AND
CORRECT SOLUTIONS WITH RATIONALE LATEST UPDATE
OF THIS YEAR ALREADY GRADED A+
This comprehensive 200-question examination bank is specifically designed
for the NHCO Phlebotomy Exam, covering the full scope of phlebotomy
practice from patient preparation to specimen handling and safety protocols.
Each question presents a unique clinical scenario involving venipuncture
techniques, capillary punctures, tube selection, order of draw, additive
identification, complications management, and infection control procedures.
Topics include patient identification, site selection, syncope prevention,
hematoma management, needle gauges, blood culture collection, and handling
of special patient populations. No question is repeated, ensuring thorough
preparation for the certification examination and clinical competency
assessment.
1. A phlebotomist is preparing to perform a venipuncture on a patient who reports
a history of fainting during previous blood draws. Which intervention is most
appropriate to prevent syncope?
A) Have the patient lie supine with legs elevated
B) Have the patient sit upright with head between knees
C) Have the patient stand during the procedure
D) Have the patient hold their breath during the draw
Answer: A
Rationale: Patients with a history of vasovagal syncope should be drawn in a
supine position to prevent fainting. Elevating the legs improves venous return.
Standing or sitting upright increases the risk of syncope.
2. A phlebotomist is selecting a vein for venipuncture in the antecubital area.
Which vein is the preferred first choice for routine venipuncture?
A) Basilic vein
B) Cephalic vein
C) Median cubital vein
D) Median antebrachial vein
Answer: C
,Rationale: The median cubital vein is the preferred site because it is large, well-
anchored, and less likely to roll. It is also less painful and has fewer nearby nerves
and arteries compared to the basilic and cephalic veins.
3. A patient is on anticoagulant therapy. Which needle gauge is most appropriate
for routine venipuncture in this patient?
A) 18 gauge
B) 20 gauge
C) 22 gauge
D) 25 gauge
Answer: C
Rationale: A 22-gauge needle is appropriate for routine venipuncture in patients on
anticoagulants because it is smaller and causes less trauma. Larger gauges increase
bleeding risk. Smaller gauges may hemolyze specimens.
4. A phlebotomist accidentally punctures a patient's radial artery during a
venipuncture attempt. Which immediate action should the phlebotomist take?
A) Apply pressure to the site for at least 5 minutes
B) Apply a tourniquet above the site
C) Elevate the arm above the heart
D) Apply ice to the site
Answer: A
Rationale: Accidental arterial puncture requires firm pressure for at least 5 minutes
to prevent hematoma formation and control bleeding. Elevation and ice are not
primary interventions. A tourniquet is not used for arterial bleeding control.
5. A blood specimen for a complete blood count is collected in a lavender-top tube.
What is the additive in this tube and its primary function?
A) Sodium citrate; prevents clotting by binding calcium
B) EDTA; prevents clotting by chelating calcium
C) Heparin; prevents clotting by inhibiting thrombin
D) Sodium fluoride; preserves glucose
Answer: B
Rationale: Lavender-top tubes contain EDTA (ethylenediaminetetraacetic acid),
which chelates calcium and prevents blood from clotting. It is used for hematology
tests such as CBC. Sodium citrate is in light blue tops, heparin in green tops, and
fluoride in gray tops.
6. A phlebotomist is performing a venipuncture and the patient suddenly becomes
pale and diaphoretic. What is the priority action?
,A) Complete the draw quickly and then assess
B) Remove the needle, apply pressure, and assess the patient
C) Lower the patient's head below the heart
D) Administer smelling salts
Answer: B
Rationale: The first priority is to remove the needle to prevent injury, apply
pressure to the site, and assess the patient for syncope or other reactions. Lowering
the head may help, but needle removal and patient safety come first.
7. A patient requires a blood culture collection. Which is the correct antiseptic for
site preparation before blood culture collection?
A) Isopropyl alcohol 70%
B) Povidone-iodine or chlorhexidine gluconate
C) Hydrogen peroxide
D) Betadine followed by alcohol
Answer: B
Rationale: Blood cultures require a more rigorous skin preparation. Chlorhexidine
gluconate or povidone-iodine is the recommended antiseptic. Alcohol alone is not
sufficient. A two-step process (iodine then alcohol) may be used but chlorhexidine
is preferred.
8. A phlebotomist is collecting a specimen for a coagulation study (PT/INR).
Which tube should be used and what is the correct order of draw?
A) Light blue top tube, drawn before any other tubes
B) Light blue top tube, drawn after sterile tubes but before additive tubes
C) Light blue top tube, drawn last
D) Light blue top tube, drawn after the lavender top tube
Answer: B
Rationale: Light blue top tubes containing sodium citrate are used for coagulation
studies. They should be drawn after blood culture tubes (sterile) but before other
additive tubes to prevent contamination with additives from other tubes.
9. A phlebotomist is preparing to draw blood from a patient with an IV line in the
left arm. What is the best practice regarding venipuncture site selection?
A) Draw from the arm with the IV, below the IV site
B) Draw from the arm with the IV, above the IV site
C) Draw from the opposite arm if possible
D) Draw from the same arm after stopping the IV infusion
Answer: C
, Rationale: The preferred practice is to draw from the opposite arm when an IV is in
place. If not possible, the draw should be performed below the IV site, and the IV
should be stopped for a few minutes before drawing to prevent contamination with
IV fluids.
10. A phlebotomist notes that a patient's vein is small and rolling. Which needle
gauge and technique should be used?
A) 21 gauge needle with a 15-degree angle
B) 23 gauge butterfly needle with a shallow angle
C) 18 gauge needle with a 30-degree angle
D) 20 gauge needle with a 45-degree angle
Answer: B
Rationale: A butterfly needle (23 gauge) with a shallow angle of 10 to 15 degrees
is best for small or rolling veins. Butterfly needles allow better control. Larger
gauges and steeper angles increase the risk of going through the vein.
11. A phlebotomist collects a specimen in a gray-top tube. Which test is most
commonly associated with this tube?
A) Complete blood count
B) Coagulation studies
C) Glucose tolerance testing
D) Chemistry panel
Answer: C
Rationale: Gray-top tubes contain sodium fluoride and potassium oxalate. Sodium
fluoride preserves glucose by inhibiting glycolysis, and potassium oxalate prevents
clotting. They are used for glucose testing, including glucose tolerance tests.
12. A phlebotomist is performing venipuncture and the needle enters the vein but
no blood flows into the tube. What is the first action to troubleshoot?
A) Remove the needle and start over
B) Adjust the needle angle slightly
C) Apply a new tourniquet
D) Change the tube
Answer: B
Rationale: If the needle is in the vein but no blood flows, the needle bevel may be
against the vein wall. Slight adjustment of the angle or rotation of the needle can
correct this. Changing the tube is not the first action.
13. A patient states that they are allergic to latex. Which action should the
phlebotomist take?
CORRECT SOLUTIONS WITH RATIONALE LATEST UPDATE
OF THIS YEAR ALREADY GRADED A+
This comprehensive 200-question examination bank is specifically designed
for the NHCO Phlebotomy Exam, covering the full scope of phlebotomy
practice from patient preparation to specimen handling and safety protocols.
Each question presents a unique clinical scenario involving venipuncture
techniques, capillary punctures, tube selection, order of draw, additive
identification, complications management, and infection control procedures.
Topics include patient identification, site selection, syncope prevention,
hematoma management, needle gauges, blood culture collection, and handling
of special patient populations. No question is repeated, ensuring thorough
preparation for the certification examination and clinical competency
assessment.
1. A phlebotomist is preparing to perform a venipuncture on a patient who reports
a history of fainting during previous blood draws. Which intervention is most
appropriate to prevent syncope?
A) Have the patient lie supine with legs elevated
B) Have the patient sit upright with head between knees
C) Have the patient stand during the procedure
D) Have the patient hold their breath during the draw
Answer: A
Rationale: Patients with a history of vasovagal syncope should be drawn in a
supine position to prevent fainting. Elevating the legs improves venous return.
Standing or sitting upright increases the risk of syncope.
2. A phlebotomist is selecting a vein for venipuncture in the antecubital area.
Which vein is the preferred first choice for routine venipuncture?
A) Basilic vein
B) Cephalic vein
C) Median cubital vein
D) Median antebrachial vein
Answer: C
,Rationale: The median cubital vein is the preferred site because it is large, well-
anchored, and less likely to roll. It is also less painful and has fewer nearby nerves
and arteries compared to the basilic and cephalic veins.
3. A patient is on anticoagulant therapy. Which needle gauge is most appropriate
for routine venipuncture in this patient?
A) 18 gauge
B) 20 gauge
C) 22 gauge
D) 25 gauge
Answer: C
Rationale: A 22-gauge needle is appropriate for routine venipuncture in patients on
anticoagulants because it is smaller and causes less trauma. Larger gauges increase
bleeding risk. Smaller gauges may hemolyze specimens.
4. A phlebotomist accidentally punctures a patient's radial artery during a
venipuncture attempt. Which immediate action should the phlebotomist take?
A) Apply pressure to the site for at least 5 minutes
B) Apply a tourniquet above the site
C) Elevate the arm above the heart
D) Apply ice to the site
Answer: A
Rationale: Accidental arterial puncture requires firm pressure for at least 5 minutes
to prevent hematoma formation and control bleeding. Elevation and ice are not
primary interventions. A tourniquet is not used for arterial bleeding control.
5. A blood specimen for a complete blood count is collected in a lavender-top tube.
What is the additive in this tube and its primary function?
A) Sodium citrate; prevents clotting by binding calcium
B) EDTA; prevents clotting by chelating calcium
C) Heparin; prevents clotting by inhibiting thrombin
D) Sodium fluoride; preserves glucose
Answer: B
Rationale: Lavender-top tubes contain EDTA (ethylenediaminetetraacetic acid),
which chelates calcium and prevents blood from clotting. It is used for hematology
tests such as CBC. Sodium citrate is in light blue tops, heparin in green tops, and
fluoride in gray tops.
6. A phlebotomist is performing a venipuncture and the patient suddenly becomes
pale and diaphoretic. What is the priority action?
,A) Complete the draw quickly and then assess
B) Remove the needle, apply pressure, and assess the patient
C) Lower the patient's head below the heart
D) Administer smelling salts
Answer: B
Rationale: The first priority is to remove the needle to prevent injury, apply
pressure to the site, and assess the patient for syncope or other reactions. Lowering
the head may help, but needle removal and patient safety come first.
7. A patient requires a blood culture collection. Which is the correct antiseptic for
site preparation before blood culture collection?
A) Isopropyl alcohol 70%
B) Povidone-iodine or chlorhexidine gluconate
C) Hydrogen peroxide
D) Betadine followed by alcohol
Answer: B
Rationale: Blood cultures require a more rigorous skin preparation. Chlorhexidine
gluconate or povidone-iodine is the recommended antiseptic. Alcohol alone is not
sufficient. A two-step process (iodine then alcohol) may be used but chlorhexidine
is preferred.
8. A phlebotomist is collecting a specimen for a coagulation study (PT/INR).
Which tube should be used and what is the correct order of draw?
A) Light blue top tube, drawn before any other tubes
B) Light blue top tube, drawn after sterile tubes but before additive tubes
C) Light blue top tube, drawn last
D) Light blue top tube, drawn after the lavender top tube
Answer: B
Rationale: Light blue top tubes containing sodium citrate are used for coagulation
studies. They should be drawn after blood culture tubes (sterile) but before other
additive tubes to prevent contamination with additives from other tubes.
9. A phlebotomist is preparing to draw blood from a patient with an IV line in the
left arm. What is the best practice regarding venipuncture site selection?
A) Draw from the arm with the IV, below the IV site
B) Draw from the arm with the IV, above the IV site
C) Draw from the opposite arm if possible
D) Draw from the same arm after stopping the IV infusion
Answer: C
, Rationale: The preferred practice is to draw from the opposite arm when an IV is in
place. If not possible, the draw should be performed below the IV site, and the IV
should be stopped for a few minutes before drawing to prevent contamination with
IV fluids.
10. A phlebotomist notes that a patient's vein is small and rolling. Which needle
gauge and technique should be used?
A) 21 gauge needle with a 15-degree angle
B) 23 gauge butterfly needle with a shallow angle
C) 18 gauge needle with a 30-degree angle
D) 20 gauge needle with a 45-degree angle
Answer: B
Rationale: A butterfly needle (23 gauge) with a shallow angle of 10 to 15 degrees
is best for small or rolling veins. Butterfly needles allow better control. Larger
gauges and steeper angles increase the risk of going through the vein.
11. A phlebotomist collects a specimen in a gray-top tube. Which test is most
commonly associated with this tube?
A) Complete blood count
B) Coagulation studies
C) Glucose tolerance testing
D) Chemistry panel
Answer: C
Rationale: Gray-top tubes contain sodium fluoride and potassium oxalate. Sodium
fluoride preserves glucose by inhibiting glycolysis, and potassium oxalate prevents
clotting. They are used for glucose testing, including glucose tolerance tests.
12. A phlebotomist is performing venipuncture and the needle enters the vein but
no blood flows into the tube. What is the first action to troubleshoot?
A) Remove the needle and start over
B) Adjust the needle angle slightly
C) Apply a new tourniquet
D) Change the tube
Answer: B
Rationale: If the needle is in the vein but no blood flows, the needle bevel may be
against the vein wall. Slight adjustment of the angle or rotation of the needle can
correct this. Changing the tube is not the first action.
13. A patient states that they are allergic to latex. Which action should the
phlebotomist take?
