CST Practice Test

The CST exam from the National Board of Surgical Technology and Surgical Assisting is for graduates of CAAHEP- or ABHES-accredited surgical technology programs. This page groups our free practice sets by topic and works through sample questions with full explanations. It also sums up the official facts you need: 175 questions, 4 hours, a passing mark of 98 of 150 scored items, and a $340 first-time fee.

CST Exam at a Glance

What the CST is and how it works

According to National Board of Surgical Technology and Surgical Assisting, “Format: 175 multiple-choice questions 150 scored 25 unscored pretest items (randomly placed)”^[1]

The CST (Certified Surgical Technologist) credential is awarded by the National Board of Surgical Technology and Surgical Assisting (NBSTSA). It shows you have the knowledge to work safely as a surgical technologist in the operating room.

Eligibility: you must graduate from a CAAHEP- or ABHES-accredited surgical technology program.

Delivery and format: you take the exam on a computer at a PSI test center. It is offered year-round, by appointment, after you are approved to test. You get 4 hours for 175 multiple-choice questions. Only 150 are scored. The other 25 are unscored pretest items placed at random, so you cannot tell which ones they are. Treat every question as if it counts.

Scoring: you pass by answering 98 of the 150 scored questions correctly. Current students who test at a PSI center get their score report by secure email link within 48 business hours. If you test another way, the timing may be different.

Fees and retakes: the first-time fee is $340, or $230 for AST members and $160 for military students. Each retake costs $300, and you can make up to 3 attempts per calendar year.

Renewal: certification runs on a 2-year cycle. You renew with 30 AST-approved CE credits and a $40 fee, or by taking the exam again ($440/$540).

Employer and state rules for surgical technologists vary, and fees can change. Check the current details at nbstsa.org before you apply.

CST content outline and where to practise each area

The content areas below are copied from the official CST content outline published by National Board of Surgical Technology and Surgical Assisting. The right-hand column shows which of our practice sets covers it.

Worked examples: how to reason through CST questions

These are practice questions written for this site, not questions from the real exam. Each explanation shows why the right answer is right and why the others are wrong.

Example 1

Question: During a carotid endarterectomy, the surgical technologist should have which shunt available to maintain cerebral perfusion while the carotid artery is clamped?

1. Javid shunt
2. Fogarty catheter
3. Pruitt-Inahara shunt
4. Argyle shunt

Answer: C. Pruitt-Inahara shunt

Explanation:

C, Pruitt-Inahara shunt, is the keyed answer. Its balloon tips inflate inside the common and internal carotid arteries. That holds the shunt in place and keeps blood flowing to the brain while the artery is clamped and opened.

B, Fogarty catheter, is an embolectomy catheter that pulls clots out of a vessel. It does not carry blood past a clamp. A, Javid, and D, Argyle, are also carotid shunts that some surgeons prefer. They have no balloon tips and are usually held with external clamps or tourniquets. The question is testing whether you know the balloon-tipped design.

Rule to remember: the choice of shunt depends on the surgeon, so check the preference card. Know which device restores flow (a shunt) and which removes clot (a Fogarty).

Example 2

Question: Which type of surgical drain works by passive gravity drainage and does not use suction?

1. Jackson-Pratt (JP) drain
2. Blake drain with bulb suction
3. Penrose drain
4. Hemovac drain

Answer: C. Penrose drain

Explanation:

C, Penrose drain, is correct. It is a soft, flat, open tube. Fluid leaves the wound by gravity and capillary action, with no suction attached.

A, Jackson-Pratt, and B, Blake drain with bulb suction, are closed drains connected to a compressible bulb. Squeezing the bulb creates gentle negative pressure. D, Hemovac, is also a closed suction drain. It uses a spring-loaded canister that pulls fluid out as it expands.

Rule to remember: if a drain has a bulb, canister or reservoir that you compress to create negative pressure, it is active (suction) drainage. The Penrose is the classic passive drain. It is open to the dressing, so expect it to be secured with a safety pin or suture and covered with absorbent dressings.

Example 3

Question: During a laparoscopic cholecystectomy, the scrub tech notices the laparoscope is fogging repeatedly. The MOST efficient intraoperative solution is:

1. Requesting a full scope exchange from SPD, halting the case
2. Warming the scope tip or applying anti-fog solution to clear the lens without interrupting flow
3. Asking the surgeon to proceed without visualization
4. Documenting the issue and addressing it post-case

Answer: B. Warming the scope tip or applying anti-fog solution to clear the lens without interrupting flow

Explanation:

B is correct. A scope fogs when a cooler lens meets the warm, humid air inside the abdomen. Warming the scope tip in a warmer or warm saline, or wiping on anti-fog solution, fixes the cause in moments and keeps the case moving.

A stops the case for a problem that does not need a new scope. C is unsafe: operating without a clear view risks injury to the bile duct, vessels or bowel. D puts off a problem that affects the patient right now, and documentation does not restore vision.

Rule to remember: when a question asks for the MOST efficient fix, choose the action that solves the problem at the field without putting patient safety or sterility at risk. Have warm water or anti-fog solution ready before the scope goes in so you can act without delay.

How to use these practice tests

Here is a simple way to prepare with these sets and the official material:

1. Start with the official outline. Get the current CST content outline and candidate information from nbstsa.org. Note its content areas: Perioperative Care, Basic Science and Ancillary Duties.
2. Take a baseline. Do a broad set such as Surgical Procedures and Techniques without notes. Mark every question you guessed on, not only the ones you got wrong.
3. Work by topic. Spend most of your time on perioperative skills: Asepsis and Sterilization, Counts and Documentation and Instrument Tray Assembly. Then move on to Surgical Anatomy and Pharmacology and Anesthesia.
4. Read every explanation. For each miss, write the rule down in a sentence, the way the worked examples above do.
5. Build stamina. Before test day, sit a long timed session close to the real 4 hours so the pacing feels familiar.
6. Finish with your weak spots. Redo the sets where you scored lowest, then reread your list of rules the night before.

Sources & last verified

1. National Board of Surgical Technology and Surgical Assisting — number of questions, time limit, score release (official source). “Format: 175 multiple-choice questions 150 scored 25 unscored pretest items (randomly placed)” Verified Oct 21, 2026.
2. National Board of Surgical Technology and Surgical Assisting — exam fee, retake fee, testing window (official source). “The CST Examination price for those who have never been certified before is $340. We offer a deeply discounted fee of $230 for AST members…” Verified Oct 21, 2026.
3. National Board of Surgical Technology and Surgical Assisting — passing score (official source). “98 on scored questions means you’ve passed!” Verified Oct 21, 2026 · source checked Oct 19, 2026.
4. National Board of Surgical Technology and Surgical Assisting — retake policy (official source). “Up to 3 exam attempts per calendar year Payment of examination retake fee of $300 required for each retake” Verified Oct 21, 2026.
5. National Board of Surgical Technology and Surgical Assisting — validity, renewal (official source). “CE Credits Required Live CE Requirement CST® 2 years 30 4 Live Credits” Verified Oct 21, 2026 · source checked Oct 19, 2026.
6. test-takers.psiexams.com — delivery (official source). “Certified Surgical Technologist Onsite (Test Center)” Verified Oct 21, 2026.
7. National Board of Surgical Technology and Surgical Assisting — eligibility (official source). “To be eligible to sit for the NBSTSA CST® exam you have to graduate from a CAAHEP or ABHES accredited surgical technology program.” Verified Oct 21, 2026 · source checked Oct 19, 2026.
8. National Board of Surgical Technology and Surgical Assisting — other (official source). “perioperative care” Verified Oct 22, 2026.

How we verify: editorial & fact-checking policy. Report an error: contact us.