CMDRT - Certified Medical Device Reprocessing Technician Low-Temperature Sterilization Questions and Answers — Questions and Answers
Question 1: A flexible endoscope cannot be sterilized using steam due to its heat-sensitive nature. Which of the following low-temperature sterilization methods is incompatible with devices containing cellulose-based materials like paper or linen?
- Hydrogen Peroxide Gas Plasma (Correct answer)
- Ethylene Oxide (EO)
- Ozone (O3)
- Peracetic Acid Immersion
Correct answer: Hydrogen Peroxide Gas Plasma
Hydrogen peroxide gas plasma sterilization is not suitable for items containing cellulose, such as paper and linen, because these materials absorb the hydrogen peroxide, which can lead to cycle cancellation or incomplete sterilization.
Question 2: A hospital's MDRD processes many heat-sensitive, complex devices. They are considering a low-temperature sterilization method known for its safety, as its primary byproducts are non-toxic. Which method breaks down into water and oxygen?
- Ethylene Oxide (EO)
- Formaldehyde
- Vaporized Hydrogen Peroxide (VHP) (Correct answer)
- Glutaraldehyde
Correct answer: Vaporized Hydrogen Peroxide (VHP)
Vaporized Hydrogen Peroxide (VHP) is considered an environmentally safe sterilization method because the active hydrogen peroxide vapor breaks down into harmless byproducts: water and oxygen. This contrasts with methods like Ethylene Oxide, which leave toxic residues requiring lengthy aeration.
Question 3: An MDRT is preparing a load for an Ethylene Oxide (EO) sterilizer. Which of the following is a critical parameter that must be controlled and monitored for a successful EO sterilization cycle?
- Generation of a plasma state
- Deep vacuum pressure below 1 millibar
- Relative humidity (Correct answer)
- Acidic pH level
Correct answer: Relative humidity
The effectiveness of Ethylene Oxide (EO) sterilization depends on the simultaneous control of four essential parameters: gas concentration, temperature, exposure time, and relative humidity. Humidity is crucial because water molecules help carry the EO gas to the microbial DNA to destroy it.
Question 4: After a successful low-temperature sterilization cycle using hydrogen peroxide gas plasma, a technician opens the sterilizer door. What is the immediate next step regarding the processed devices?
- They must be placed in an aerator for 8-12 hours.
- They require a quarantine period in a negative pressure room.
- They can be handled safely and are ready for immediate use or storage. (Correct answer)
- They need to be rinsed with sterile water to remove residue.
Correct answer: They can be handled safely and are ready for immediate use or storage.
A significant advantage of hydrogen peroxide gas plasma sterilization is that the byproducts are non-toxic (water vapor and oxygen), eliminating the need for an aeration period. Once the cycle is complete, the items can be safely handled and are ready for use or storage.
Question 5: Which type of biological indicator (BI) is used to monitor the efficacy of both Vaporized Hydrogen Peroxide (VHP) and Hydrogen Peroxide Gas Plasma sterilization cycles?
- Bacillus atrophaeus spores
- Bacillus subtilis spores
- Geobacillus stearothermophilus spores (Correct answer)
- Clostridium sporogenes spores
Correct answer: Geobacillus stearothermophilus spores
Geobacillus stearothermophilus spores are highly resistant to both steam and vaporized hydrogen peroxide sterilization processes, making them the standard microorganism used in biological indicators for these methods.
Question 6: A medical device reprocessing department is deciding between Ethylene Oxide (EO) and Vaporized Hydrogen Peroxide (VHP) for a new low-temperature sterilizer. A key consideration is the post-cycle processing time. What is a primary disadvantage of EO compared to VHP in this regard?
- EO cycles are significantly hotter.
- EO requires a lengthy aeration period to remove toxic residues. (Correct answer)
- EO cannot be used for devices with long lumens.
- EO sterilizers require more frequent maintenance.
Correct answer: EO requires a lengthy aeration period to remove toxic residues.
Ethylene Oxide is a toxic and carcinogenic gas that can be absorbed by certain materials. Therefore, after the sterilization cycle, a mandatory aeration period (which can last for several hours) is required to allow the residual gas to dissipate to safe levels before the devices can be handled or used. VHP does not have this requirement.
CMDRT - Certified Medical Device Reprocessing Technician Low-Temperature Sterilization Questions and Answers
A flexible endoscope cannot be sterilized using steam due to its heat-sensitive nature.
Which of the following low-temperature sterilization methods is incompatible with devices containing cellulose-based materials like paper or linen?