CET Infection Control & Sterilization Techniques 3 — Questions and Answers
Question 1: According to SGNA guidelines, what is the maximum time allowed for a reprocessed endoscope to hang in storage before it must be reprocessed again?
- 24 hours
- 48 hours
- 5–7 days, per facility policy based on validated evidence (Correct answer)
- 30 days if sealed in a sterile wrap
Correct answer: 5–7 days, per facility policy based on validated evidence
SGNA and AORN recommend that facilities establish a hang time based on validated evidence; typically 5–7 days in a properly ventilated cabinet is accepted, but facilities must follow their validated policy.
Question 2: What distinguishes a high-level disinfectant from a sterilant?
- High-level disinfectants kill all microorganisms including spores with sufficient contact time; sterilants do not kill spores
- Sterilants destroy all forms of microbial life; HLD kills most pathogens but may not eliminate high numbers of bacterial spores (Correct answer)
- HLD is applied via automated reprocessors only; sterilants are always manual
- There is no practical difference; the terms are interchangeable
Correct answer: Sterilants destroy all forms of microbial life; HLD kills most pathogens but may not eliminate high numbers of bacterial spores
Sterilants destroy all microbial life including high levels of spores; HLD eliminates most pathogens but may leave trace spore populations, making sterilization the higher standard.
Question 3: A colonoscope is classified under Spaulding's classification as which category, requiring which reprocessing level?
- Critical — requires sterilization
- Semi-critical — requires at minimum high-level disinfection (Correct answer)
- Non-critical — requires low-level disinfection
- Semi-critical — requires intermediate-level disinfection only
Correct answer: Semi-critical — requires at minimum high-level disinfection
Colonoscopes contact intact mucous membranes and are classified as semi-critical, requiring at minimum high-level disinfection between patient uses.
Question 4: Which PPE ensemble is required when manually cleaning contaminated flexible endoscopes?
- Gloves only
- Gloves and face mask
- Gloves, waterproof gown, eye protection, and surgical mask or face shield (Correct answer)
- Sterile gloves and a hair cover only
Correct answer: Gloves, waterproof gown, eye protection, and surgical mask or face shield
Manual cleaning involves aerosolization and splashing of potentially infectious fluids; full PPE including gloves, waterproof gown, eye protection, and mask/face shield is required.
Question 5: What effect does biofilm formation have on endoscope reprocessing?
- Biofilm enhances the penetration of disinfectants into the channel walls
- Biofilm protects embedded organisms from disinfectants and increases risk of patient transmission (Correct answer)
- Biofilm has no effect because HLD concentrations are sufficient to penetrate it
- Biofilm forms only on the exterior of scopes and is removed by wiping
Correct answer: Biofilm protects embedded organisms from disinfectants and increases risk of patient transmission
Biofilm creates a protective matrix that shields embedded microorganisms from disinfectants, making adequate initial cleaning essential to prevent biofilm-related reprocessing failures.
Question 6: In an automated endoscope reprocessor (AER), what role does the rinse cycle play?
- It re-sterilizes the scope after HLD
- It removes residual disinfectant that could cause chemical injury to patients or scope components (Correct answer)
- It introduces enzymatic cleaners to complete the cleaning process
- It applies a lubricant to internal channels
Correct answer: It removes residual disinfectant that could cause chemical injury to patients or scope components
The rinse cycle removes residual high-level disinfectant from channels and surfaces, preventing chemical burns to mucosal tissue during subsequent patient procedures.
Question 7: When performing the pre-cleaning step at the point of use, what is the immediate action the technician should take after scope withdrawal from the patient?
- Immerse the insertion tube in enzymatic solution for 10 minutes
- Wipe the insertion tube and suction air/water to flush channels while still at bedside (Correct answer)
- Transport the scope to the reprocessing room without any bedside steps
- Apply a dry sterile drape over the scope and transport
Correct answer: Wipe the insertion tube and suction air/water to flush channels while still at bedside
Immediately after scope withdrawal, the insertion tube is wiped with a moist cloth and channels are flushed with air and water to remove gross debris before biofilm can begin forming.
CET Infection Control & Sterilization Techniques 3
According to SGNA guidelines, what is the maximum time allowed for a reprocessed endoscope to hang in storage before it must be reprocessed again?