CER Endoscope Sterilization Methods Questions and Answers 3 — Questions and Answers
Question 1: What is the primary advantage of hydrogen peroxide gas plasma sterilization over ETO for endoscope reprocessing?
- Lower cost per sterilization cycle
- No toxic residuals requiring aeration after the cycle (Correct answer)
- Effective on all lumen diameters including those under 1mm
- Faster sterilization cycle times than all other methods
Correct answer: No toxic residuals requiring aeration after the cycle
Hydrogen peroxide gas plasma sterilization leaves no toxic residuals, eliminating the lengthy aeration period required after ETO sterilization.
Question 2: Which sterilization method requires a mandatory aeration period after the cycle to remove toxic residuals before instruments can be used on patients?
- Hydrogen peroxide gas plasma (STERRAD)
- Peracetic acid liquid sterilization (STERIS)
- Ethylene oxide (ETO) (Correct answer)
- Vaporized hydrogen peroxide (VHP)
Correct answer: Ethylene oxide (ETO)
ETO sterilization requires a post-cycle aeration period because ETO and its byproducts (ethylene chlorohydrin, ethylene glycol) are toxic and must off-gas from materials before patient contact.
Question 3: What is the primary mechanism by which ethylene oxide (ETO) achieves sterilization of microorganisms?
- Protein denaturation through elevated heat
- Alkylation of DNA, RNA, and proteins disrupting cellular function (Correct answer)
- Oxidation of microbial cell membranes
- Disruption of bacterial cell wall synthesis
Correct answer: Alkylation of DNA, RNA, and proteins disrupting cellular function
ETO sterilizes by alkylating the nucleic acids and proteins of microorganisms, which prevents cellular replication and kills all forms of microbial life.
Question 4: The STERRAD sterilization system manufactured by ASP uses which sterilant as its primary active agent?
- Ethylene oxide gas
- Glutaraldehyde solution
- Peracetic acid solution
- Hydrogen peroxide gas plasma (Correct answer)
Correct answer: Hydrogen peroxide gas plasma
The STERRAD system uses vaporized hydrogen peroxide combined with low-temperature plasma to achieve sterilization of heat- and moisture-sensitive instruments.
Question 5: What is the typical temperature range used during an ethylene oxide (ETO) sterilization cycle?
- 37–55°C (98–131°F) (Correct answer)
- 60–80°C (140–176°F)
- 121–134°C (250–273°F)
- 170–180°C (338–356°F)
Correct answer: 37–55°C (98–131°F)
ETO sterilization operates at low temperatures (37–55°C), making it suitable for heat-sensitive endoscopes that cannot withstand steam autoclave temperatures.
Question 6: Which liquid chemical sterilant system uses peracetic acid as its active ingredient to achieve sterilization of flexible endoscopes?
- STERRAD NX (ASP)
- STERIS System 1E (Correct answer)
- Cidex OPA (ortho-phthalaldehyde)
- Metricide 28 (glutaraldehyde)
Correct answer: STERIS System 1E
The STERIS System 1E uses peracetic acid as the active sterilant and provides liquid chemical sterilization for heat-sensitive flexible endoscopes at the point of use.
Question 7: Which endoscope characteristic renders it INCOMPATIBLE with hydrogen peroxide gas plasma (STERRAD) sterilization?
- Flexible design with articulating bending section
- Lumens with an internal diameter less than 1mm or length-to-diameter ratio exceeding manufacturer limits (Correct answer)
- Presence of stainless-steel components within the insertion tube
- Outer sheath made of heat-sensitive polymers
Correct answer: Lumens with an internal diameter less than 1mm or length-to-diameter ratio exceeding manufacturer limits
Long, narrow lumens restrict hydrogen peroxide diffusion and plasma penetration, resulting in inadequate sterilant contact and potential sterilization failure.
CER Endoscope Sterilization Methods Questions and Answers 3
What is the primary advantage of hydrogen peroxide gas plasma sterilization over ETO for endoscope reprocessing?