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NBSTSA CST EXAM/NBSTSA CST Final Exam
Newest Exam Preparation With Complete Questions
And Correct Answers With Rationales | Already
Graded A+||Brand New Version!!
QUESTION 1
A surgical technologist is preparing the sterile field for a laparotomy.
Which of the following actions violates aseptic technique?
A) Opening the inner wrapper of a sterile package away from the body
B) Placing sterile items within the 1-inch border of the sterile drape
C) Pouring sterile solution into a basin held off the edge of the table
D) Maintaining eye contact with the sterile field while moving around it
Answer: B) Placing sterile items within the 1-inch border of the sterile
drape
Explanation: The 1-inch border around the periphery of a sterile drape is
considered non-sterile because it is the area most likely to be touched or
contaminated during setup. Sterile items must be placed at least 1 inch
inward from this edge to maintain sterility. Opening inner wrappers
away from the body prevents shedding of microorganisms onto the
field, pouring solutions into a basin held off the table avoids wicking
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contaminants from the table surface, and maintaining visual awareness
of the field is a fundamental safety practice.
QUESTION 2
During a total hip arthroplasty, the surgeon requests a pulse lavage
system. What is the primary purpose of this device?
A) To remove bone cement remnants
B) To irrigate and debride the surgical wound with pressurized fluid
C) To maintain hemostasis through thermal coagulation
D) To aspirate bone marrow for grafting
Answer: B) To irrigate and debride the surgical wound with pressurized
fluid
Explanation: Pulse lavage systems deliver pressurized irrigation fluid to
mechanically dislodge debris, bacteria, and nonviable tissue from the
wound bed, particularly in orthopedic procedures. This reduces the
bioburden and prepares the bone surface for implant fixation. While
bone cement removal may involve lavage, the primary function is
irrigation and debridement, not cement extraction, thermal hemostasis,
or marrow aspiration.
QUESTION 3
Which of the following hemostatic agents works by providing a physical
matrix for platelet aggregation and clot formation without requiring an
active clotting cascade?
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A) Thrombin powder
B) Oxidized regenerated cellulose
C) Gelatin sponge
D) Bone wax
Answer: C) Gelatin sponge
Explanation: Gelatin sponge (e.g., Gelfoam) acts as a mechanical
scaffold that absorbs blood and provides a surface for platelet
adherence and aggregation. It does not require an active clotting
cascade, making it effective even in heparinized patients. Thrombin
powder directly activates fibrinogen to fibrin, oxidized cellulose
generates an artificial clot via pH-mediated erythrocyte aggregation,
and bone wax is purely a mechanical occlusive agent for bone bleeding.
QUESTION 4
A patient is positioned in the prone position for a lumbar laminectomy.
Which pressure point requires particular attention to prevent injury?
A) Heels
B) Ocular globes
C) Sciatic nerve
D) Brachial plexus
Answer: B) Ocular globes
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Explanation: In the prone position, the face is typically placed on a
padded headrest or horseshoe headrest. Direct pressure on the ocular
globes can cause retinal ischemia, corneal abrasion, or even blindness.
The heels are at risk in the supine position, the sciatic nerve is
vulnerable in the lithotomy position, and the brachial plexus is at risk in
the lateral decubitus or Trendelenburg position with arm board
extension.
QUESTION 5
What is the recommended method for cleaning surgical instruments
immediately after use in the operating room?
A) Soaking in normal saline solution
B) Wiping with alcohol-impregnated gauze
C) Rinsing with sterile distilled water
D) Placing in a container with enzymatic detergent
Answer: D) Placing in a container with enzymatic detergent
Explanation: Enzymatic detergents break down organic matter such as
blood, fat, and protein, preventing them from drying and adhering to
instruments. Immediate placement in an enzymatic solution is the
standard of care for point-of-use cleaning. Normal saline is corrosive to
stainless steel, alcohol fixes proteinaceous debris, and sterile distilled
water alone does not provide sufficient enzymatic breakdown.
QUESTION 6
NBSTSA CST EXAM/NBSTSA CST Final Exam
Newest Exam Preparation With Complete Questions
And Correct Answers With Rationales | Already
Graded A+||Brand New Version!!
QUESTION 1
A surgical technologist is preparing the sterile field for a laparotomy.
Which of the following actions violates aseptic technique?
A) Opening the inner wrapper of a sterile package away from the body
B) Placing sterile items within the 1-inch border of the sterile drape
C) Pouring sterile solution into a basin held off the edge of the table
D) Maintaining eye contact with the sterile field while moving around it
Answer: B) Placing sterile items within the 1-inch border of the sterile
drape
Explanation: The 1-inch border around the periphery of a sterile drape is
considered non-sterile because it is the area most likely to be touched or
contaminated during setup. Sterile items must be placed at least 1 inch
inward from this edge to maintain sterility. Opening inner wrappers
away from the body prevents shedding of microorganisms onto the
field, pouring solutions into a basin held off the table avoids wicking
,2|Page
contaminants from the table surface, and maintaining visual awareness
of the field is a fundamental safety practice.
QUESTION 2
During a total hip arthroplasty, the surgeon requests a pulse lavage
system. What is the primary purpose of this device?
A) To remove bone cement remnants
B) To irrigate and debride the surgical wound with pressurized fluid
C) To maintain hemostasis through thermal coagulation
D) To aspirate bone marrow for grafting
Answer: B) To irrigate and debride the surgical wound with pressurized
fluid
Explanation: Pulse lavage systems deliver pressurized irrigation fluid to
mechanically dislodge debris, bacteria, and nonviable tissue from the
wound bed, particularly in orthopedic procedures. This reduces the
bioburden and prepares the bone surface for implant fixation. While
bone cement removal may involve lavage, the primary function is
irrigation and debridement, not cement extraction, thermal hemostasis,
or marrow aspiration.
QUESTION 3
Which of the following hemostatic agents works by providing a physical
matrix for platelet aggregation and clot formation without requiring an
active clotting cascade?
,3|Page
A) Thrombin powder
B) Oxidized regenerated cellulose
C) Gelatin sponge
D) Bone wax
Answer: C) Gelatin sponge
Explanation: Gelatin sponge (e.g., Gelfoam) acts as a mechanical
scaffold that absorbs blood and provides a surface for platelet
adherence and aggregation. It does not require an active clotting
cascade, making it effective even in heparinized patients. Thrombin
powder directly activates fibrinogen to fibrin, oxidized cellulose
generates an artificial clot via pH-mediated erythrocyte aggregation,
and bone wax is purely a mechanical occlusive agent for bone bleeding.
QUESTION 4
A patient is positioned in the prone position for a lumbar laminectomy.
Which pressure point requires particular attention to prevent injury?
A) Heels
B) Ocular globes
C) Sciatic nerve
D) Brachial plexus
Answer: B) Ocular globes
, 4|Page
Explanation: In the prone position, the face is typically placed on a
padded headrest or horseshoe headrest. Direct pressure on the ocular
globes can cause retinal ischemia, corneal abrasion, or even blindness.
The heels are at risk in the supine position, the sciatic nerve is
vulnerable in the lithotomy position, and the brachial plexus is at risk in
the lateral decubitus or Trendelenburg position with arm board
extension.
QUESTION 5
What is the recommended method for cleaning surgical instruments
immediately after use in the operating room?
A) Soaking in normal saline solution
B) Wiping with alcohol-impregnated gauze
C) Rinsing with sterile distilled water
D) Placing in a container with enzymatic detergent
Answer: D) Placing in a container with enzymatic detergent
Explanation: Enzymatic detergents break down organic matter such as
blood, fat, and protein, preventing them from drying and adhering to
instruments. Immediate placement in an enzymatic solution is the
standard of care for point-of-use cleaning. Normal saline is corrosive to
stainless steel, alcohol fixes proteinaceous debris, and sterile distilled
water alone does not provide sufficient enzymatic breakdown.
QUESTION 6
