CRNFA Surgical Instrumentation and Equipment 2 — Questions and Answers
Question 1: Which electrosurgical mode uses a continuous waveform to achieve tissue cutting with minimal hemostasis?
- Blend mode
- Coagulation mode
- Cut mode (Correct answer)
- Bipolar mode
Correct answer: Cut mode
The cut mode delivers a continuous, unmodulated waveform that rapidly vaporizes tissue, producing a clean cut with minimal lateral thermal spread.
Question 2: The CRNFA notes that a laparoscopic trocar is labeled '12 mm.' This measurement refers to the:
- Length of the trocar sleeve
- Inner diameter of the trocar cannula
- Outer diameter of the trocar cannula (Correct answer)
- Diameter of the insufflation port
Correct answer: Outer diameter of the trocar cannula
Trocar sizes are designated by the outer diameter of the cannula, which determines the largest instrument that can be passed through it.
Question 3: Which of the following describes the correct technique when passing a sharp instrument to the surgeon?
- Place it directly into the surgeon's palm handle-first while maintaining eye contact
- Use a neutral zone or hands-free technique to avoid percutaneous injuries (Correct answer)
- Verbally announce the instrument and hand it tip-first for speed
- Pass it any way that is most convenient given the operative situation
Correct answer: Use a neutral zone or hands-free technique to avoid percutaneous injuries
AORN and OSHA standards recommend a neutral zone (hands-free passing technique) for all sharps to reduce percutaneous injury risk in the OR.
Question 4: A Harrington ('sweetheart') retractor is most commonly used to retract which structure?
- Brain tissue during craniotomy
- The liver during upper abdominal surgery (Correct answer)
- The bladder during pelvic surgery
- The lung during thoracotomy
Correct answer: The liver during upper abdominal surgery
The Harrington retractor, named for its heart-shaped blade, is designed to lift and retract the liver and spleen during upper abdominal procedures.
Question 5: Which vessel-sealing device uses bipolar energy combined with pressure to create a permanent seal on vessels up to 7 mm in diameter?
- LigaSure (Correct answer)
- Harmonic scalpel
- Monopolar ESU pencil
- Argon beam coagulator
Correct answer: LigaSure
LigaSure uses bipolar radiofrequency energy and mechanical pressure to denature collagen and elastin, creating a permanent seal on vessels up to 7 mm.
Question 6: The Harmonic scalpel achieves hemostasis primarily through which mechanism?
- Electrical current generating heat via resistance
- Ultrasonic vibration causing protein coagulation at low temperatures (Correct answer)
- Argon gas–enhanced coagulation
- Mechanical compression of vessel walls only
Correct answer: Ultrasonic vibration causing protein coagulation at low temperatures
The Harmonic scalpel vibrates at 55,500 Hz, denaturing proteins through mechanical energy at temperatures of 50–100°C, well below those of conventional ESU.
Question 7: When handling instruments that have been exposed to Creutzfeldt-Jakob disease (CJD) prions, standard sterilization with steam autoclave is:
- Sufficient if a full prevacuum cycle is used
- Insufficient; prions require specialized decontamination protocols (Correct answer)
- Sufficient when combined with glutaraldehyde soaking
- Sufficient only if high-temperature 273°F (134°C) cycles are doubled
Correct answer: Insufficient; prions require specialized decontamination protocols
Prions are not inactivated by standard steam sterilization or chemical disinfectants; WHO and CDC recommend instrument destruction or highly specialized alkaline/autoclaving protocols.
CRNFA Surgical Instrumentation and Equipment 2
Which electrosurgical mode uses a continuous waveform to achieve tissue cutting with minimal hemostasis?