Oklahoma Clinical Laboratory
Assistant Assessment Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf.
1. Which phase of laboratory testing includes patient identification,
specimen collection, labeling, transport, and preparation before the
specimen is analyzed?
A. Analytical phase
B. Post-analytical phase
C. Pre-analytical phase
D. Verification phase
The pre-analytical phase encompasses all activities that occur before
actual testing, including correct patient identification, specimen
collection, labeling, handling, and transportation. Errors during this
phase can significantly compromise laboratory results.
, 2. A clinical laboratory assistant is preparing to collect a blood
specimen. Which action is most important for preventing patient-
identification errors?
A. Confirming the patient's room number
B. Asking another staff member to identify the patient
C. Checking the specimen tube before approaching the patient
D. Using at least two approved patient identifiers and comparing them
with the laboratory order
Two patient identifiers, such as the patient's full name and date of birth,
should be compared with the laboratory request before collection to
reduce the risk of collecting a specimen from the wrong patient.
3. Which antiseptic is commonly used for routine venipuncture when
there is no special testing requirement?
A. Sterile water
B. Hydrogen peroxide only
C. 70% isopropyl alcohol
D. Sodium chloride solution
70% isopropyl alcohol is commonly used to disinfect the venipuncture
site for routine blood collection because it effectively reduces skin
microorganisms and evaporates readily.
4. During venipuncture, a patient suddenly becomes pale, diaphoretic,
and lightheaded. What should the laboratory assistant do first?
,A. Continue collecting the remaining tubes
B. Ask the patient to stand and walk around
C. Stop the procedure and protect the patient from falling or injury
D. Immediately administer oral medication
Pallor, sweating, and lightheadedness can indicate a vasovagal
reaction. The immediate priority is to stop the collection and protect the
patient from injury while obtaining appropriate assistance.
5. Which vein is generally the first choice for routine venipuncture in
the antecubital area?
A. Basilic vein
B. Cephalic vein
C. Median basilic vein
D. Median cubital vein
The median cubital vein is generally preferred because it is usually large,
relatively stationary, and often provides good access while reducing the
likelihood of contacting nerves or arteries.
6. What is the primary purpose of applying a tourniquet during
venipuncture?
A. Sterilize the collection site
B. Increase arterial blood flow
C. Promote venous filling and make the vein easier to locate
D. Prevent hemolysis in every specimen
, A tourniquet temporarily restricts venous return, causing the veins to
become more prominent and easier to palpate and access.
7. Why should a tourniquet generally not remain applied for an
excessively long period?
A. It causes immediate arterial occlusion
B. It sterilizes the blood
C. Prolonged venous stasis can alter certain laboratory analytes and
contribute to inaccurate results
D. It prevents blood from entering the collection tube
Prolonged tourniquet application can cause hemoconcentration and
alter concentrations of some analytes, potentially affecting laboratory
results.
8. Which sequence correctly represents the commonly accepted order
of draw for evacuated blood collection tubes?
A. Lavender, blue, serum, green, gray
B. Gray, lavender, green, serum, blue
C. Blood culture, light blue, serum, green, lavender, gray
D. Serum, gray, lavender, light blue, blood culture
The order of draw helps prevent additive carryover between tubes. A
commonly taught sequence is blood cultures, citrate tubes, serum tubes,
heparin tubes, EDTA tubes, and fluoride/oxalate tubes.
9. Which additive is present in a light-blue-top tube?
Assistant Assessment Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf.
1. Which phase of laboratory testing includes patient identification,
specimen collection, labeling, transport, and preparation before the
specimen is analyzed?
A. Analytical phase
B. Post-analytical phase
C. Pre-analytical phase
D. Verification phase
The pre-analytical phase encompasses all activities that occur before
actual testing, including correct patient identification, specimen
collection, labeling, handling, and transportation. Errors during this
phase can significantly compromise laboratory results.
, 2. A clinical laboratory assistant is preparing to collect a blood
specimen. Which action is most important for preventing patient-
identification errors?
A. Confirming the patient's room number
B. Asking another staff member to identify the patient
C. Checking the specimen tube before approaching the patient
D. Using at least two approved patient identifiers and comparing them
with the laboratory order
Two patient identifiers, such as the patient's full name and date of birth,
should be compared with the laboratory request before collection to
reduce the risk of collecting a specimen from the wrong patient.
3. Which antiseptic is commonly used for routine venipuncture when
there is no special testing requirement?
A. Sterile water
B. Hydrogen peroxide only
C. 70% isopropyl alcohol
D. Sodium chloride solution
70% isopropyl alcohol is commonly used to disinfect the venipuncture
site for routine blood collection because it effectively reduces skin
microorganisms and evaporates readily.
4. During venipuncture, a patient suddenly becomes pale, diaphoretic,
and lightheaded. What should the laboratory assistant do first?
,A. Continue collecting the remaining tubes
B. Ask the patient to stand and walk around
C. Stop the procedure and protect the patient from falling or injury
D. Immediately administer oral medication
Pallor, sweating, and lightheadedness can indicate a vasovagal
reaction. The immediate priority is to stop the collection and protect the
patient from injury while obtaining appropriate assistance.
5. Which vein is generally the first choice for routine venipuncture in
the antecubital area?
A. Basilic vein
B. Cephalic vein
C. Median basilic vein
D. Median cubital vein
The median cubital vein is generally preferred because it is usually large,
relatively stationary, and often provides good access while reducing the
likelihood of contacting nerves or arteries.
6. What is the primary purpose of applying a tourniquet during
venipuncture?
A. Sterilize the collection site
B. Increase arterial blood flow
C. Promote venous filling and make the vein easier to locate
D. Prevent hemolysis in every specimen
, A tourniquet temporarily restricts venous return, causing the veins to
become more prominent and easier to palpate and access.
7. Why should a tourniquet generally not remain applied for an
excessively long period?
A. It causes immediate arterial occlusion
B. It sterilizes the blood
C. Prolonged venous stasis can alter certain laboratory analytes and
contribute to inaccurate results
D. It prevents blood from entering the collection tube
Prolonged tourniquet application can cause hemoconcentration and
alter concentrations of some analytes, potentially affecting laboratory
results.
8. Which sequence correctly represents the commonly accepted order
of draw for evacuated blood collection tubes?
A. Lavender, blue, serum, green, gray
B. Gray, lavender, green, serum, blue
C. Blood culture, light blue, serum, green, lavender, gray
D. Serum, gray, lavender, light blue, blood culture
The order of draw helps prevent additive carryover between tubes. A
commonly taught sequence is blood cultures, citrate tubes, serum tubes,
heparin tubes, EDTA tubes, and fluoride/oxalate tubes.
9. Which additive is present in a light-blue-top tube?
