NBSTSA Sterile Technique & Asepsis 2 — Questions and Answers
Question 1: Which sterilization method is preferred for heat-sensitive surgical instruments?
- Steam autoclave
- Dry heat oven
- Ethylene oxide (EtO) gas (Correct answer)
- Boiling water
Correct answer: Ethylene oxide (EtO) gas
Ethylene oxide gas sterilization is preferred for heat-sensitive items because it operates at low temperatures.
Question 2: What is the correct action when a circulator passes a non-sterile item over the sterile field?
- Accept the item if it was done quickly
- Consider the entire sterile field contaminated (Correct answer)
- Discard only the item that was passed over
- Continue if the item did not touch the field
Correct answer: Consider the entire sterile field contaminated
Any non-sterile item passing over the sterile field contaminates it because particles may fall from above onto the field.
Question 3: During case setup, sterile drapes must be placed on the back table by:
- Holding them at arm's length and shaking them open
- Unfolding them from the center outward while keeping hands above table level (Correct answer)
- Asking the circulator to spread them on the table
- Placing them folded and then unfolding once all items are added
Correct answer: Unfolding them from the center outward while keeping hands above table level
Drapes are unfolded from the center outward while keeping hands above table level to prevent contamination of the sterile field from below.
Question 4: Which biological indicator organism is used to verify steam autoclave sterilization efficacy?
- Bacillus atrophaeus
- Geobacillus stearothermophilus (Correct answer)
- Clostridium difficile
- Staphylococcus aureus
Correct answer: Geobacillus stearothermophilus
Geobacillus stearothermophilus spores are the standard biological indicator for steam (moist heat) sterilization monitoring.
Question 5: A flash (immediate use) steam sterilization cycle is appropriate for:
- Routine sterilization of instrument trays
- An instrument that was dropped and is urgently needed (Correct answer)
- Sterilizing implantable devices as a backup
- All instruments used in total joint replacement
Correct answer: An instrument that was dropped and is urgently needed
Flash sterilization is reserved for emergency situations such as when a critical instrument is dropped and immediately needed, not for routine processing.
Question 6: The purpose of a chemical indicator (Class 1 process indicator) placed on the outside of a sterilization pack is to:
- Confirm that sterilization conditions were met inside the pack
- Show that the pack has been exposed to the sterilization process (Correct answer)
- Replace biological indicator monitoring
- Measure steam penetration to the pack center
Correct answer: Show that the pack has been exposed to the sterilization process
Class 1 indicators (e.g., autoclave tape) only confirm exposure to the sterilization process, not that sterilization conditions were achieved.
NBSTSA Sterile Technique & Asepsis 2
Which sterilization method is preferred for heat-sensitive surgical instruments?