Name two high-level disinfection methods for heat-sensitive instruments such as endoscopes.

• A. Hydrogen peroxide-based disinfection and peracetic acid solutions.
• B. Steam sterilization and dry heat.
• C. Ethanol and isopropyl alcohol.
• D. Glutaraldehyde alone.

Answer: (A)

When reprocessing heat‑sensitive instruments like endoscopes, you can’t rely on heat-based sterilization because the devices would be damaged. Instead, high‑level disinfection methods are used to inactivate a broad range of microorganisms while preserving the instrument’s integrity.

Two common chemical high‑level disinfection methods are hydrogen peroxide–based disinfection and peracetic acid solutions. Hydrogen peroxide–based systems use accelerated or stabilized hydrogen peroxide to achieve rapid, effective killing of bacteria, viruses, fungi, and many other pathogens within the complex channels of an endoscope. Peracetic acid solutions are highly potent and effective even in the presence of organic matter, offering strong antimicrobial action with relatively short cycles and compatibility with the device materials when used as directed. Together, they provide reliable high‑level disinfection suitable for lumen-containing, heat‑sensitive instruments.

Steam sterilization and dry heat are not appropriate for these devices because the temperatures involved would damage them. Ethanol and isopropyl alcohol are mainly surface disinfectants and do not reliably achieve high‑level disinfection throughout the internal channels of endoscopes. Glutaraldehyde is indeed a high‑level disinfectant, but it’s a single method with longer cycle times and more handling hazards, which is why the pair of hydrogen peroxide–based and peracetic acid methods is the preferred answer.