A review of current reprocessing guidelines for flexible endoscopes

Healthcare Purchasing News, August, 2005 by Greg Skorczewski

All too frequently national news carries a story of healthcare providers who have inadvertently exposed patients to infectious organisms because they have failed to properly reprocess invasive equipment. These unfortunate incidents are likely much more common than we imagine, frequently going unnoticed or unreported.

Some experts estimate the incidence of infections from inadequately disinfected colonoscopies to be as rare as 1 per 1.8 million procedures. Others say there may be as many as 270,000 infections (2) out of the total of approximately 10 million flexible endoscopies performed each year in the U. S. The truth is, no one knows how frequently infectious caused by inadequately disinfected endoscopes occur because there is no mechanism in place to collect the data.

The key to preventing the spread of infection from inadequately reprocessed instruments is clear: standardize and improve cleaning, disinfecting and sterilizing activities, monitor and validate reprocessing technology, and require strict adherence to industry-accepted process standards. The following review of current guidelines is intended to assist you in the development of policies that are appropriate for your facility or unit.

High Level Disinfection (HLD)

In 1968, a classification system for selecting the appropriate level of disinfection or sterilization for medical devices was developed by Dr. E. H. Spaulding. (1) Since then, this system has been widely adopted and has been frequently cited by the Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and other professional organizations. Based on the definitions in this system, flexible endoscopes fall into the semi-critical classification requiring a minimum of high-level disinfection (HLD). (1,2,11) By definition, instruments that are sterilized in the HLD process will be free of all vegetative microorganisms, mycrobacteria, small or non-lipid viruses, medium or lipid viruses, fungal spores, and some but not all bacterial spores.

Validating the HLD process, on the other hand, can be a challenge. There is no definitive way to assess and document that all surfaces of the scope have been adequately cleaned and exposed to the disinfectant. Likewise, there is no way to know for certain whether the reprocessing has achieved the required level of microbial kill. The assumption is that HLD reprocessing strictly adheres to a sequence of cleaning steps and controlled exposure to an approved disinfectant. Nonetheless, there have been documented examples of endoscopes carrying residual soil and viable microorganisms through the HLD process. (3,4,5,6,7,8) In these cases, failure to consistently follow the accepted guidelines for cleaning and disinfection has been cited as a common cause. (4,5,7,9,10).

The four phases of reprocessing

There are four fundamental phases involved in the reprocessing of flexible endoscopes. They are: (1) cleaning; (2) disinfection; (3) drying; and (4) storage/reuse. (See Figure 1.) Within each of these phases, there are specific steps to be taken. Within each step, there is a sequence of specific actions recommended by the instrument manufacturer: The exact sequence of actions and equipment needs may differ slightly depending on the type of endoscope and the manufacturer, so before establishing a protocol it is recommended that one first consult the manufacturer's operating instructions.

[FIGURE 1 OMITTED]

1. Cleaning:

Pre Cleaning: Immediately after use, clean the external surfaces and components of the endoscope. Repeatedly actuate the valves flushing and aspirating water or enzymatic solution through all accessible channels to remove all organic (e. g., blood, tissue) and other residues.

Mechanical Cleaning: Leak test before immersing endoscope. Manually clean internal and external surfaces, including brushing internal channels and flushing each internal channel with water and an enzymatic detergent.

2. Disinfection: Immerse the endoscope in high-level disinfectant (chemical sterilant). To eliminate air pockets and ensure contact of the germicide with the internal channels perfuse disinfectant into all accessible channels such as the suction/biopsy channel and air/water channel and expose for the time recommended for specific products. Rinse the endoscope and all channels with sterile water or filtered water (commonly used with AEWD, Automated Endo scope Washer Disinfector); if this is not feasible, tap water may be used.

3. Dry: Flush the insertion tube and inner channels with 70% to 90% ethyl or isopropyl alcohol then dry with forced air.

4. Store: Store the endoscope in a way that prevents recontamination and promotes drying (e. g., hung vertically).

Guidelines

To obtain copies of the authoritative guidelines for reprocessing of flexible endoscopes, (11) log onto The Society of Gastroenterology Nurses and Associates (SGNA) Website [http://www. sgna.org] or the Association for Professionals in Infection Control and Epidemiology, Inc. [http://www.apic.org]. The most recent guide line, "The Multi-Society Guideline for Reprocessing Flexible Gastrointestinal Endoscopes" (11), was published in 2003 by Gastrointestinal Endoscopy and Infection Control and Hospital Epidemiology. To obtain copies of this document, visit the Society for Healthcare Epidemiology of America, Inc. (SHEA) website [http://www.shea-online.org/ PositionPapers. html]. This document employs the CDC model of categorizing recommendations based on existing scientific data or theoretical rationale." (see figure 2)