The guidelines governing the cleaning and disinfecting of endoscopes so that these instruments can be used again on patients are more than 50 years old.

Dr. Stephen Spanos

This needs to change, as our medical director, Dr. Stephen Spanos, recently wrote in Infection Control Today. In his op-ed, Spanos takes a closer a look at the Spaulding classification and the increasing complexity of bronchoscopes, duodenoscopes and others as federal regulators report new findings on contamination risks.

Millions of endoscopy procedures are performed annually in the U.S., critical to diagnosing problems in the airways, the gastrointestinal and urinary systems and in the ears, nose and throat.

The complexity of these scopes, and the fact that they become contaminated during use, makes cleaning and disinfecting them properly between uses very difficult. Even after being cleaned and disinfected, studies show a significant number of endoscopes remain contaminated with potential pathogens.

“Now that we have a clearer picture of the challenges and risks associated with endoscope reprocessing, we know that clarifying the Spaulding classification can prevent further contamination.”

—Dr. Stephen Spanos

Repeated outbreaks, according to new research from Dr. William Rutala—a University of North Carolina School of Medicine professor—have been blamed on inadequate cleaning and inappropriate disinfection (a failure to perfuse all channels, for example), damaged endoscopes or flaws in the design (the duodenoscope elevator channel has been cited), and issues with automated endoscope reprocessors (AERs). The complexity of endoscopes, with their unwieldy, long, narrow channels, right-angle turns and small crevices make them extremely difficult to clean.

In addition, microorganisms often reside in scratches, grooves, and irregular surfaces that invariably occur on endoscopes subject to regular use. If endoscopes are not completely dried after cleaning, any remaining viable microbes can rapidly proliferate and colonize the instrument. The age of the endoscope and improper storage have also been found to contribute to higher contamination rates.

As Spanos notes, while improvements to cleaning and monitoring guidelines and the design are important, revising the way that endoscopes are classified in the Spaulding scheme will be key in tackling the problem of contamination.

Developed in 1968 by Dr. Earle Spaulding, this classification scheme defined how an object should be disinfected based on its intended use. According to Dr. Spaulding’s protocol, instruments defined as “semi-critical” are any devices that contact intact mucous membranes. The recommended reprocessing guideline for semi-critical objects is cleaning followed by high-level disinfection (HLD).

Items defined as “critical” are those that enter sterile tissue or the vascular system or through which blood flows, and require cleaning followed by sterilization. It should also be noted that many of the tools which are used in these endoscopes have been deemed as critical in the Spaulding classification.

This lack of uniformity between scope and tool creates a problem, as the critical tool will become contaminated as it passes through a dirty channel.

Now that we have a clearer picture of the challenges and risks associated with endoscope reprocessing, Spanos writes, we know that clarifying the Spaulding classification can prevent further contamination. How? For one, by defining as critical and requiring sterilization of any complex devices—such as bronchoscopes, cystoscopes and duodenoscopes—that directly or indirectly enter normal sterile tissue or the vascular system.

For more from Dr. Spanos on the Spaulding Classification and why it needs to be updated, click here.