Varying High-Level Disinfection Practices Can Have Untoward Results

By Libby Chinnes

Do we assume that an item has been high-level disinfected or sterilized appropriately in our surgery center? How can patients truly have faith that proper practices are used on their devices?

Critical assessment of high-level disinfection (HLD) practices as well as sterilization is a fundamental responsibility of not only the infection preventionist but also reprocessing department leadership. All healthcare workers involved in the HLD process must be familiar with best practices of HLD.

According to the Association for the Advancement of Medical Instrumentation (AAMI), HLD is a process that kills all microbial organisms but not necessarily large numbers of bacterial spores. Spaulding classification recommends this process be utilized on semi-critical equipment, such as endoscopes or instruments, which contact mucous membranes but do not enter sterile tissue.

While many of the steps in HLD are not covered in this article, the following are some tips for guidance on the process based on infractions witnessed in the field which can lead to items not being properly processed, patient safety issues and citations from surveyors.

High-Level Disinfection Tips

Have you noticed dirty instruments with blood and tissue being received in decontamination area? Are they transported in an open container with water to decontamination?

Tip: Instruments/scopes must be “pre-cleaned” properly at the bedside before arriving in decontamination area. In the operating or procedure room, this entails wiping the scope down with a sponge moistened with detergent solution as specified by manufacturer’s instructions as soon as the procedure is over. (Note: In surgery, the instrument should be wiped with sterile water throughout the procedure) Scope lumens should also have the lumens flushed with detergent solution. The precleaned item should be placed in a closed, leak-proof, puncture-resistant, biohazard labeled container and delivered to decontamination area.

AAMI suggests one of three methods for keeping the item moist until it is decontaminated: 1) placing a towel moistened with water (not saline) over instruments; 2) placing the item inside a package designed to maintain humid conditions; or3) applying a treatment designed for pretreatment. These methods delay the rapid process of biofilm development which makes cleaning more difficult and interferes with disinfection and/or sterilization.

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Are current manufacturer’s instructions for use (IFU) available for reprocessing staff to follow?

Tip: An item has been validated by the manufacturer’s processes to be cleaned, disinfected or sterilized. If every step of the IFUs are not followed, then we cannot assume that the item is correctly processed. If IFUs are not current, then proper processes may not be followed.

Remember that IFUs pertain to instruments, equipment, detergents, disinfectant, biological and chemical indicators, etc. For instance, detergents and enzymatics may state a specific volume of water to be used (i.e., measured), a specific temperature to use (measured by a thermometer) and specific concentration of the ingredient. If these processes are not followed, the item will not be considered properly cleaned.

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Are you taking time after cleaning and rinsing the item to be sure that the item is really clean before subjecting it to high level disinfection?

Tip: AAMI, the Association for periOperative Nurses (AORN) and the Society of Gastroenterology Nurses and Associates (SGNA) all recommend that this step be included in reprocessing. Visual inspection does not guarantee that decontamination is complete, but it can be considered a safety “time out” per SGNA to ensure the item is visually clean before proceeding to the next step of HLD.

Visually inspect the item for conditions that could affect the disinfection process (e.g., cracks, corrosion, discoloration, retained debris) with magnification and adequate lighting. Use a camera or borescope for inspecting internal channels, if available. Repeat manual cleaning steps if the item is not visually clean. Remove damaged items from service for repair or disposal.

Facilities should determine a method of manual cleaning verification. Ideally, per AAMI, cleaning verification by users should include a) visual inspection plus other verification methods that allow the assessment of both external surfaces as well as internal channels of medical devices, b) testing of the cleaning efficacy of equipment and c:) monitoring key cleaning parameters such as the volume and temperature of the cleaning solution per manufacturer’s IFU.

For verification of routine cleaning processes, users should incorporate commercially available, rapid-cleaning monitors for residual bioburden that verify the functionality of the mechanical cleaning equipment (if used) and the cleanliness of the specific devices after manual or mechanical cleaning is completed. If the results are positive, this allows for the re-cleaning of the item before disinfection. These tests (frequency determined by the individual institution) may also be useful for training and competency testing.

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Are your staff trained and competent to reprocess items properly by HLD?

Tip: Leadership is ultimately responsible for the quality of reprocessing activities. Managers must be educated, knowledgeable and empowered to address infractions “in the moment”

for patient and staff safety. Healthcare worker competencies must be maintained at least on initiation of a duty, annually and on introduction of new equipment or accessories.

Libby Chinnes, RN, CIC, is an infection prevention and control consultant with IC Solutions. Write her at


American National Standards Institute Inc./Association for the Advancement of Medical Instrumentation (ANSI/AAMI). ST91:2015. Flexible and semi-rigid endoscope processing in health care facilities. 2015.

American National Standards Institute Inc./Association for the Advancement of Medical Instrumentation (ANSI/AAMI). ST79:2017. Comprehensive guide to steam sterilization and sterility assurance in health care facilities. 2017.

AORN Guidelines for Perioperative Practice. 2018.

SGNA Standards of Infection Prevention in Reprocessing of Flexible Gastrointestinal Endoscopes (2018).

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