CER - Certified Endoscope Reprocessor High-Level Disinfection Processes Questions and Answers — Questions and Answers
Question 1: A reprocessor is preparing a reusable high-level disinfectant (HLD) solution, such as glutaraldehyde, for use. According to best practices, what must be done before immersing the first endoscope of the day?
- Record the date the solution was opened and discard it after 24 hours.
- Test the solution for its minimum effective concentration (MEC) using a product-specific test strip. (Correct answer)
- Add a neutralizing agent to the solution to prevent damage to the endoscope.
- Heat the solution to 50°C (122°F) to accelerate the disinfection process.
Correct answer: Test the solution for its minimum effective concentration (MEC) using a product-specific test strip.
Before each use, reusable HLD solutions must be tested with a product-specific test strip to ensure the active ingredient is at or above the minimum effective concentration (MEC). This quality control step verifies that the solution is still capable of achieving high-level disinfection. The reuse life (e.g., 14 or 28 days) is also tracked, and the solution is discarded when the MEC fails or the reuse life expires, whichever comes first.
Question 2: During a manual high-level disinfection process using ortho-phthalaldehyde (OPA), which of the following represents a critical parameter that must be strictly followed according to the manufacturer's instructions for use (IFU)?
- A 30-minute soak time at 15°C (59°F).
- A 12-minute soak time at 20°C (68°F). (Correct answer)
- A 5-minute soak time at any ambient temperature.
- A 20-minute soak time followed by an alcohol rinse only.
Correct answer: A 12-minute soak time at 20°C (68°F).
The effectiveness of high-level disinfectants like OPA is dependent on specific parameters of time and temperature. A common FDA-cleared contact condition for OPA is a 12-minute soak time at a minimum of 20°C (68°F) for manual reprocessing. Deviating from these validated parameters can lead to disinfection failure.
Question 3: A facility's automated endoscope reprocessor (AER) completes a high-level disinfection cycle. Which of the following is the most critical next step to prevent recontamination of the endoscope before storage?
- Wiping the exterior with a sterile gauze.
- A final rinse with unfiltered tap water.
- Immediate placement in a non-ventilated cabinet.
- Thorough rinsing with sterile or filtered water, followed by an alcohol flush and forced air drying. (Correct answer)
Correct answer: Thorough rinsing with sterile or filtered water, followed by an alcohol flush and forced air drying.
After HLD, endoscopes must be thoroughly rinsed with sterile or bacteria-free water (e.g., passed through a 0.2-micron filter) to remove toxic disinfectant residue. This is followed by flushing channels with 70% alcohol to aid in drying and then purging all channels with forced, filtered air until visibly dry. Inadequate rinsing can cause patient injury, and inadequate drying can allow remaining waterborne microorganisms to proliferate.
Question 4: When selecting a high-level disinfectant for endoscope reprocessing, which characteristic of Peracetic Acid is a notable advantage?
- It is non-corrosive to all metals, including brass and copper.
- It requires an alkaline activator before each use.
- It has a long reuse life, typically exceeding 60 days.
- It lacks toxic aldehyde vapors and has environmentally friendly byproducts (acetic acid and oxygen). (Correct answer)
Correct answer: It lacks toxic aldehyde vapors and has environmentally friendly byproducts (acetic acid and oxygen).
Peracetic acid is a strong oxidizing agent that is effective as a high-level disinfectant. A key advantage is that it breaks down into harmless byproducts: acetic acid (vinegar) and oxygen, making it more environmentally friendly and reducing toxic vapor concerns compared to aldehyde-based disinfectants. However, it can be corrosive to some metals like brass and copper.
Question 5: A reprocessing technician is documenting the manual HLD process for a colonoscope. Which of the following data points is LEAST critical to record in the reprocessing log?
- The lot number of the high-level disinfectant.
- The name of the patient the endoscope was previously used on. (Correct answer)
- The result of the MEC test strip.
- The soak time and temperature of the disinfection.
Correct answer: The name of the patient the endoscope was previously used on.
While patient information is crucial for tracking in case of an exposure event, the name of the *previous* patient is not a critical parameter of the HLD process itself that needs to be logged for process quality control. The essential HLD process records include the lot number of the HLD, the MEC test result, the soak time and temperature, and the identifier of the endoscope being reprocessed to ensure traceability and confirm that all critical parameters were met.
Question 6: Which of the following scenarios would require the immediate disposal of a reusable high-level disinfectant solution, regardless of the number of days it has been in use?
- The temperature of the solution drops slightly below the manufacturer's recommendation.
- The test strip indicates a concentration below the Minimum Effective Concentration (MEC). (Correct answer)
- The logbook for the solution is misplaced.
- A new brand of test strips is introduced for use with the existing solution.
Correct answer: The test strip indicates a concentration below the Minimum Effective Concentration (MEC).
The Minimum Effective Concentration (MEC) is the lowest concentration of the active chemical that can still achieve high-level disinfection. If a test strip indicates the solution's concentration has fallen below this level, it is no longer effective and must be discarded immediately, even if it has not reached its stated reuse-life date (e.g., 14 or 28 days).
A reprocessor is preparing a reusable high-level disinfectant (HLD) solution, such as glutaraldehyde, for use.
According to best practices, what must be done before immersing the first endoscope of the day?