Controversy erupts over whether to disinfect or sterilize endoscopes
New estimate: 2.7% of procedures with disinfected scopes cause infections
As if same-day surgery managers didn’t have enough to worry about: A newly published article estimates that 2.7% of the approximately 10 million procedures done each year in the United States with nonsterilized endoscopes cause infections.1
Actually, the 2.7% figure is "probably quite conservative," according to the author, David L. Lewis, PhD, research microbiologist at the Environmental Protection Agency’s (EPA) National Exposure Research Laboratory in Athens, GA. Lewis is on assignment to the University of Georgia in Athens to study infection control with dental and medical devices. His views don’t represent official views of the EPA.
The Food and Drug Administration and the Centers for Disease Control and Prevention (CDC) recently issued a public health advisory on reprocessing endoscopes. The advisory followed a CDC report that found infections were transmitted by bronchoscopes inadequately reprocessed in automated endoscope reprocessors. (For more on the advisory, see Same-Day Surgery, January 2000, p. 9. For more on the initial CDC report, see SDS, September 1999, p. 104.)
Most national groups, as well as the CDC, recognize high level disinfection as the standard for endoscopes. However, Lewis calls on health care providers to use a peracetic acid sterilization process or sheath technology. Only one manufacturer provides the sheath technology: Vision-Sciences in Natick, MA. (To contact manufacturer, see source box, p. 15.) Olympus Optical Co. in Tokyo has patented the technology, but a product is not yet on the market.
Although there always is a cost involved in purchasing new technology, these costs are offset by freedom from federal standards that require ventilation systems, personal protection equipment, and monitoring of glutaraldehyde vapors, Lewis said in his article.
When it comes to the groups that say disinfection with glutaraldehyde is sufficient, Lewis’ opinions and words are strong. "Current infection control standards are based on willful ignorance, not sound science," he said in his article. "Upgrading infection control standards for endoscopy, therefore, is not so much about resolving differences in scientific opinions. Instead, it is simply about getting people who oversee the issue to put the welfare of patients above their own professional interests."
And Lewis’ stance of bucking the system doesn’t stop there. For providers who disinfect, "My advice is that physicians should inform their patients that there is a small, but real, risk of infection from nonsterilized endoscopes, and let patient make the decision on whether they’re comfortable with disinfection vs. sterilization."
That advice leaves providers with the difficult decisions of whether to sterilize and whether to inform patients if they don’t. And they face another dilemma: Conflicting recommendations on soak times for endoscopes from national groups and manufacturers.
"I’ve certainly not seen such a level of confusion over what to do in any other area of medical practice, regarding infection control," Lewis says.
Why sterilize? Disinfectants are not effective unless a device is completely clean, Lewis emphasizes. "Plain and simple: Any difficult to clean medical device is going to have blood and other patient material that will escape any type of manual cleaning."
Newly published research indicates that endoscopes retain patient materials, even after following cleaning instructions from manufacturers and medical associations, he said in his article.2 And manufacturers have known for some time that endoscopes cannot be completely cleaned, he claimed in his article, citing an Olympus Optical Co. patent.3
"Therefore, I recommend that these devices be submitted to sterilization process, which is more rigorous than disinfection," he says. Lewis recommends using an automated peracetic acid sterilization system. Currently, only one system is on the market: Steris System 1 Process from Steris Corp. in Mentor, OH. The price is $16,200. (For contact information, see source box, p. 15.)
Others disagree with the recommendation for sterilization.
"There are no data independent of corporate influence that documents a validated method for cleaning and sterilizing the instrument," says Lynne Sehulster, PhD, M(ASCP), microbiologist at the CDC.
Reports have been published in popular press and medical periodicals that are geared toward medical professionals, but aren’t peer-reviewed scientific literature, Sehulster says. "Some of these articles call for sterilization of instruments. The thing is, there are no data to support that these instruments can be sterilized."
The worldwide standard for cleaning endoscopes is high-level disinfection, she says.
Is a 10-minute soak acceptable?
Citing research, Lewis claims that most health care providers soak endoscopes in glutaraldehyde for only 10 minutes.4,5 This short soak time is particularly common in outpatient surgery, where facilities are often in a time crunch, he says. (For information on a new product that provides high level disinfection in 12 minutes, see resource box, at right.)
According to Lewis’ article, it takes 34.8 minutes for heat and germicides to penetrate slightly viscous bodily fluid when 2% glutaraldehyde is used.
"If a health care facility makes a decision to use high level disinfection rather than sterilization procedure, then I strongly recommend they follow manufacturers guidelines for those high level disinfectants," Lewis says. "It seems like it’s not even worth saying, but the fact is, look at the label on 2% glutaraldehyde. It says, Soak for 45 minutes to achieve highest level of disinfection,’ yet few medical facilities are following those guidelines."
While it’s true that some facilities perform a 10-minute soak, these same facilities tend to have outstanding quality assurance on their cleaning and reprocessing, Sehulster says. "They keep adequate documentation of all parameters that need to be measured: concentration of glutaraldehyde, the procedures used for cleaning. Their documentation is really without peer. With all this documentation, plus staff are dedicated to cleaning and reprocessing, the ones I know that do 10 minutes are almost a model that other clinics should aspire to."
However, the only way a facility can adequately disinfect in 10 minutes is "if you clean endoscopes within an inch of their lives," Sehulster emphasizes.
Research indicates that staff who paid the greatest attention to proper cleaning had fewer reports of contaminated instruments after cleaning and reprocessing compared to facilities that had lapses in this process, she says.6
"From my review of literature, I haven’t found one which found a problem with a thoroughly cleaned and disinfected scope," Sehulster says. "There was always some break in protocol."
Meticulous manual cleaning followed by high level disinfection with 20-minute exposure to 2% glutaraldehyde is supported by the Association of periOperative Registered Nurses in Denver; the American Society for Gastrointestinal Endoscopy in Manchester, MA; the American Gastroenterological Association in Bethesda, MD; the American College of Gastroenterology in Arlington, VA; and the Association for Profes-sionals in Infection Control and Epidemiology in Washington, DC; as well as the Society for Gastroenterology Nurses and Associates (SGNA) in Chicago, according to SGNA’s "Guideline for the Use of High Level Disinfectants and Sterilants for Reprocessing of Flexible Gastrointestinal Endoscopes." (For information on how to order a copy of the SGNA guideline, see resource box, above. For information on proper use of flash sterilization, see SDS, September 1999, p. 101. For information on problems with cleaning bronchoscopes, see SDS, September 1999, p. 104.)
The 20-minute recommendation is different from the 45-minute exposure recommended on the glutaraldehyde label because the current label assumes a "worst-case scenario" when there’s been no cleaning of the endoscope before chemical exposure, according to Sehulster.
A study at the University of North Carolina compared a 45-minute soak time with thoroughly cleaned items undergoing a 20-minute soak time. "Through this independent observation, they determined the most critical part of the operation was the cleaning," Sehulster says. "If you thoroughly clean the instrument or surface, in essence you are reducing the organic contamination on the surface. That in turn sets up a better opportunity for the chemical germicide to do its job."
Managers often are reluctant to soak instruments for 45 minutes because the chemicals are strong and might reduce the use time of the instruments, she says. Thorough cleaning with 20-minute exposure to high level disinfectant is the middle ground, Sehulster says. "For all practical purposes, and according to world wide standards, it is considered appropriate for making the instrument ready for the next patient."
References
1. Lewis DL. A sterilization standard for endoscopes and other difficult to clean medical devices. Practical Gastro-enterology 1999; 23:28-56.
2. Alfa MJ, Degagne P, and Olson N. Worst-case soiling levels for patient-used flexible endoscopes before and after cleaning. Am J Infect Control 1999; 27:392-401.
3. Olympus Optical Co., Ltd. Tokyo, Japan. 1995. U.S. Patents 5,408,991; 5,419,311; 5,431,150; 5,458,132; 5,458,133.
4. Gorse G J, Messner RL. Infection control practices in gastrointestinal endoscopy in the United States: A national survey. Infect Control Hosp Epidemiol 1991; 12:289-296.
5. Foss D, Monagan D. A National Survey of Physicians’ and Nurses’ Attitudes Toward Endoscope Cleaning and the Potential for Cross-infection. Chicago: Society of Gastroenterology Nurses and Associates; 1992.
6. Deva AK, Vickery K, Zou J, et al. Detection of persistent vegetative bacteria and amplified viral nucleic acid from in-use testing of gastrointestinal endoscopes. J Hosp Infect 1998; 39:149-157.
For more information on disinfection and sterilization of endoscopes, contact:
• David L. Lewis, PhD, Research Microbiologist, National Exposure Research Laboratory, Environmental Protection Agency, Athens, GA. E-mail: [email protected]. Web site: members.aol.com/lewisdavel.
• Lynne Sehulster, PhD, M(ASCP), Microbiologist, Centers for Disease Control and Prevention, NCID Hospital Infection Program, Mail Stop C16, Atlanta, GA 30333. Telephone: (404) 639-2314. Fax: (404) 639-3241. E-mail: [email protected].
For more information on the Steris System 1 Process, contact:
• Steris Corp., Customer Service, 9260 Progress Parkway, Mentor, OH 44060-1834. Telephone: (800) 548-4873 or (440) 354-2600. Fax: (440) 639-4450. Web site: www.steris.com.
For more information on sheath technology, contact:
• Vision-Sciences, 9 Strathmore Road, Natick, MA 01760. Telephone: (800) 874-9975 or (508) 650-9971. Fax: (508) 650-9976. E-mail: info @visionsciences.com.
"Guideline for the Use of High Level Disinfectants and Sterilants for Reprocessing of Flexible Gastrointestinal Endoscopes" is available for $5 for members of the Society of Gastroenterology Nurses and Associates and $10 for nonmembers. Shipping and handling is $4.95. Contact:
• Society of Gastroenterology Nurses and Associates, Department of Membership Services, 401 N. Michigan Ave., Chicago, IL 60611-4267. Telephone: (800) 245-SGNA or in Illinois (312) 321-5165. E-mail: SGNA@sba. com. Web site: www.SGNA.org.
Advanced Sterilization Products, part of Johnson & Johnson, has launched a new product, Cidex OPA, a glutaraldehyde-free product that provides high level disinfection in 12 minutes. For more information, contact:
• Advanced Sterilization Products, 33 Technology Drive, Irvine, CA 92618. Telephone: (877) 672-6699. Fax: (949) 453-6353.
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