CER CER - Certified Endoscope Reprocessor Chemical Disinfectants and Germicides Questions and Answers 4 — Questions and Answers
Question 1: Which factor most significantly reduces the efficacy of glutaraldehyde when reprocessing endoscopes?
- High ambient temperature
- Presence of organic soil on the device (Correct answer)
- Low relative humidity in the reprocessing room
- Elevated pH of the rinse water
Correct answer: Presence of organic soil on the device
Organic soil (blood, mucus, bioburden) acts as a physical barrier that shields microorganisms from the disinfectant, dramatically reducing germicidal efficacy.
Question 2: A healthcare facility wants to switch from 2.4% glutaraldehyde to ortho-phthalaldehyde (OPA). Which statement about OPA is correct?
- OPA requires a longer minimum exposure time than glutaraldehyde at room temperature
- OPA does not require activation before use (Correct answer)
- OPA is less effective against mycobacteria than glutaraldehyde
- OPA must be diluted with sterile water before use
Correct answer: OPA does not require activation before use
Unlike glutaraldehyde, OPA (e.g., Cidex OPA) is a ready-to-use, pre-activated solution that does not require mixing or activation.
Question 3: The minimum effective concentration (MEC) test strip for a glutaraldehyde-based HLD solution reads below the MEC. What is the correct action?
- Add fresh disinfectant to bring the solution back up to the MEC
- Continue use for the remainder of the current shift only
- Discard the solution immediately and document the result (Correct answer)
- Retest after 30 minutes before making a decision
Correct answer: Discard the solution immediately and document the result
A solution that tests below the MEC can no longer reliably achieve high-level disinfection and must be discarded immediately per manufacturer and CDC guidelines.
Question 4: Peracetic acid (PAA) automated endoscope reprocessors (AERs) are often preferred over manual glutaraldehyde soaking primarily because they:
- Eliminate the need for manual pre-cleaning before reprocessing
- Reduce worker exposure to toxic chemical vapors (Correct answer)
- Achieve sterilization rather than high-level disinfection
- Require shorter total reprocessing cycle times
Correct answer: Reduce worker exposure to toxic chemical vapors
PAA-based AERs reduce occupational chemical exposure because the chemical is contained within a closed-loop system, limiting vapor release to staff.
Question 5: Which concentration of hydrogen peroxide is approved for high-level disinfection of heat-sensitive endoscopes when used at room temperature?
- 3%
- 6–7.5% (Correct answer)
- 10%
- 30%
Correct answer: 6–7.5%
A 7.5% (and some 6%) hydrogen peroxide formulation is FDA-cleared for HLD of heat-sensitive medical devices at room temperature.
Question 6: When using an automated endoscope reprocessor (AER) with peracetic acid, the term 'single-use cycle' refers to:
- Using the same chemical charge for no more than one endoscope per cycle
- Running the AER through one complete disinfection cycle per work day
- Discarding the peracetic acid solution after each complete AER cycle (Correct answer)
- Limiting each endoscope to one reprocessing cycle per patient case
Correct answer: Discarding the peracetic acid solution after each complete AER cycle
Peracetic acid in AERs such as the MEDIVATORS ADVANTAGE PLUS is formulated for single-use; the solution is discarded after each cycle to ensure potency.
Question 7: Which statement accurately describes the sporicidal activity of OPA compared to glutaraldehyde?
- OPA is a superior sporicide and achieves sterilization within the standard HLD contact time
- OPA is a poor sporicide compared to glutaraldehyde and cannot achieve HLD
- OPA has limited sporicidal activity, making it suitable for HLD but not sterilization (Correct answer)
- OPA and glutaraldehyde have identical sporicidal activity at equivalent concentrations
Correct answer: OPA has limited sporicidal activity, making it suitable for HLD but not sterilization
OPA has limited sporicidal activity and achieves HLD (killing vegetative bacteria, mycobacteria, viruses, fungi) but does not achieve sterilization because it cannot reliably kill bacterial spores within the HLD contact time.
CER CER - Certified Endoscope Reprocessor Chemical Disinfectants and Germicides Questions and Answers 4
Which factor most significantly reduces the efficacy of glutaraldehyde when reprocessing endoscopes?