Scoping Infectious Patients

The problem, officials said, was that some older instruments were cleaned using a process usually reserved for newer ones. About 250 patients were examined during a 60-day period and followup tests were scheduled.

Nosocomial infection is a problem that may not be fully recognized among endoscopy professionals for the same reason that it is infrequently reported by hospitals and clinics.¹ According to the US Food and Drug Administration (FDA), healthcare workers (HCWs)are at a greater risk of being infected by patients than vice versa.² The hepatitis B virus, both more common and more easily transmitted than HIV, is estimated by the Centers for Disease Control and Prevention (CDC) to infect about 250,000 Americans annually, about 10,000 of whom are HCWs.²

Since 1990, when news reports first suggested HIV could be transmitted from a healthcare provider to a patient, federal agencies and professional organizations have worked to assure patients the risk is small and provide healthcare facilities with better, more thorough infection-control precautions.

Pat Tydell, risk manager at North Chicago Veterans Administration Medical Center (VAMC) in north Chicago, Ill., emphasizes that any time nurses are going to be exposed to mucous membranes or bodily fluids, as in an endoscopy procedure, they are putting themselves at risk for a variety of infections. The general rule, therefore, is to treat all patients as if they are infectious.

"If [nurses] know they have an infectious patient, everyone is very careful. But what they need to realize is they are never sure what they have," Tydell says.

This is particularly true in this day and age, she adds, with a greater emphasis on patient confidentiality and protecting medical information.

Infectious Scopes

Instrument design is a central component to preventing contamination that leads to infection. The Association for Professionals in Infection Control and Epidemiology (APIC) reports that while recent design advances have improved the capabilities of flexible endoscopes, there have been relatively few improvements that better facilitate cleaning and disinfection.¹

Tydell says the best endoscopic instruments have few moving parts, crevices, hollows, tubes, or cavities. A retractor, for example, has no enclosed areas in which tissue can hide. Tydell says tissue or blood that has not been completely removed from an instrument can harbor bacteria and allow it to grow. In other cases, foreign proteins from the patient's body may remain on an instrument, causing a localized allergic reaction in a subsequent patient. Endoscopes and accessories should be cleaned promptly after use so that secretions do not dry.

Maureen Cain, manager of GI Endoscopy at the Mayo Clinic in Scottsdale, Ariz., emphasizes that once a procedure is finished, before the scope is processed, staff should perform a leak test to check for damage to the scope. She says this should be routine practice in all endoscopy centers.

Nurses at the Mayo Clinic have been using disposable forceps for some time. The concern with the reusable forceps was that the spike used to grab tissue could prick a staff member during cleaning, resulting in infection.

Currently most of the accessories used in therapy at the Mayo Clinic, such as snares, are disposable. Because disposable devices can be more costly, many hospitals still opt for reusable devices. Cain has seen this become an issue in a number of facilities where cutting costs is a primary concern. She points out, however, that there are costs involved in reprocessing as well.

Equipment

Meticulous endoscope cleaning by trained professionals is crucial to preventing the spread of infections such as hepatitis B and HIV. According to APIC, there continues to be wide variation in the techniques hospitals use to clean and disinfect endoscopes.¹ Because manually cleaning and disinfecting endoscopes can be both complex and time consuming, the use of automated endoscope reprocessing machines has increased in the US.³

Unfortunately, improperly functioning machines can be a source of contamination. A 1991 report by the CDC described two hospitals that found contamination in automated reprocessing machines, specifically in water holding tanks, water hoses, and air vents. The CDC linked the problem to three factors: ineffective machine design; the reuse of detergent, disinfectant, and tap water in the auto disinfector; and reservoirs and tubing that remained moist or filled with fluid for extended periods.³

In April 1990, the Olympus Corporation mailed a safety alert to all consignees of particular machine models recommending all endoscope channels be rinsed with 70% isopropyl alcohol and suctioned with forced air after machine processing. At the time of the report, the CDC said such precautions still did not ensure elimination of contamination.

Tydell says a number of factors can affect cleaning effectiveness, from a break in technique to machine malfunction. Cain points out that newer scope models may also have attachments that do not fit properly into older machines, causing openings such as biopsy channels to be blocked during cleaning. Whenever a hospital or clinic gets a new scope, she recommends checking with the manufacturer to make sure the facility has the means to process it correctly.

Cain says a misconception among the general public is that hospitals can sterilize scopes. The process used in GI centers, she says, is called high-level disinfection. At the Mayo Clinic, trained professionals first clean scopes manually, brushing each channel, and then attaching them to the machine, which runs a cycle of soaking and flushing with water, and a 30-minute glutaraldehyde soak.

Proper cleaning not only prevents infection, but also can eliminate instrument deterioration and malfunction.

At the VAMC, Tydell says personnel test their reprocessing units daily, keeping logs of infection-related information that is reported to the infection control nurse.

Disinfectants

For many years, glutaraldehyde has been the disinfectant solution of choice within healthcare facilities. The non-corrosive solution does not damage endoscopes, and is highly resistant to neutralization by organic soil. The problem with the solution, however, is the health risks it can present to staff. Cain says nurses exposed to the caustic solution have complained of headaches and skin reactions. Breathing problems have also been reported in some facilities.

Tydell says a great number of disinfectants can be dangerous to HCWs. She stresses the importance of protective equipment and clothing as well as proper ventilation where the chemicals are used. Every hospital should have an accessible safety data sheet describing the risks of handling chemicals such as glutaraldehyde. APIC suggests installing exhaust hoods for tubs if at all possible.¹

Two disinfectant solutions that are becoming more widely used in endoscopy centers are Cidex OPA and Rapicide.

The endoscopy center at Desert Samaritan Hospital in Mesa, Ariz., began using Cidex OPA as an alternative to glutaraldehyde about a year ago. Ruthanne Hays, assistant to the director of endoscopy at Desert Samaritan, says the center decided to switch to Cidex OPA because it is less toxic to staff and accomplishes disinfection in a shorter time period.

"At that time, we had a really large volume and a very small area," she says. "So we were trying to make the most out of every minute."

Though the OPA solution is more expensive than glutaraldehyde, Hays says the time saved with the shortened soak cycle compensates for higher costs.

Good Samaritan Hospital in Phoenix, Ariz., also has been working primarily with Cidex OPA for the past year. Nancy Adamson, assistant director of endoscopy at the hospital, says the OPA better meets the staff's needs because it has no smell and requires only a 12-minute soaking period, as opposed to 20 minutes when using glutaraldehyde. She says once a center becomes aware of these new options in disinfectant solutions, it is likely to switch.

At Desert Endoscopy Center in Mesa, Ariz., the disinfectant of choice is Rapicide. The center switched from glutaraldehyde to facilitate quicker scope turn over, according to Technician Mike Daigle. He adds that in his experience, glutaraldehyde has a tendency to coat scopes with a thin layer of brownish film that can build up over time and clog an instrument's smaller channels. After a couple of years, this can become a major problem, he says. So far, he has not come across any downsides to Rapicide use.

FDA regulations state: "Devices that do not penetrate the skin or come in contact with normally sterile areas of the body, such as several types of endoscopes, must be disinfected, at a minimum, with an EPA-registered and FDA-cleared disinfectant. The disinfectant selected must be of appropriate strength to kill the types of organisms that may contaminate the particular device.²"

According to APIC, continuous use of a disinfectant solution for extensive periods of time can result in dilution.¹ For this reason, commercial test kits are available for chlorine, hydrogen peroxide, and glutaraldehyde solutions to determine whether an effective concentration of active ingredients is present.

Staff

While vaccinations are more readily available than ever, many HCWs still are not vaccinated. In 1990, the FDA estimated that about 250 healthcare workers die every year from complications of HBV acquired on the job. Tydell says that while it is crucial that nurses receive at least annual health surveillance, some hospitals are cutting down on employee health functions because of cost. She says ER staff should have access to stool sample testing and X-rays on a regular basis.

Taking measures to protect the clinician will also protect the patient.² Protective attire should be worn by all endoscopy personnel and readily accessible in the endoscopy area. Protective attire includes gloves, masks, eye protection, and moisture-resistant gowns or aprons.

The FDA and the CDC also identify a number of other general safety practices including: caution in handling sharp instruments, proper disposal of sharp instruments in labeled, puncture-resistant containers, and immediate hand washing following exposure to bodily fluids.

HIV and hepatitis are among nurses primary concerns when it comes to endoscopy-related infection, Tydell says. Tuberculosis is the main concern surrounding bronchoscopy. In a 1992 American Hospital Association survey/CDC survey, 90 of 729 respondents reported nosocomial TB transmission to HCWs.⁴

In 1994, OSHA revised and published guidelines regarding the responsibility of employers in preventing the transmission of TB. The guidelines identify several control methods, including the early identification, isolation and treatment of persons with TB, use of engineering and administrative procedures to reduce exposure, and the use of respiratory protection.

Tydell says some procedures will present greater risk than others. If endoscopy complications such as perforation arise, for example, a lot of bleeding may occur. As long as the staff is practicing the right precautions and do not break technique, however, she says they are not in serious danger.

There is a level of infection-control awareness that is yet to be attained, Tydell says. "The general public is very lackadaisical about infections. They figure we have something to cure them and that they won't die and get sick from these things anymore," she says. "It is really hard to convince people that these bugs are still out there and they are much better at causing disease than we are at stopping it at this point in time."

Since 1987, the National Centers for Disease Control and Prevention and the federal agency responsible for monitoring and controlling infectious disease in the US have identified universal precautions for all HCWs to prevent the spread of HBV, HIV, and other blood-borne infections. The most fundamental precaution is the assumption that the "blood and body fluids of all patients may be infectious, and measures to protect against exposure must be observed at all times.²"

The CDC and the FDA are continually working to assess the frequency and level of endoscope contamination within hospitals and clinics. Healthcare professionals are asked to report episodes of endoscopy-related infection in patients undergoing gastrointestinal endoscopy or bronchoscopy directly to their county or state health departments, or, when applicable, to internal safety, infection control, and risk-management programs.

If it is suspected that infection is being transferred through contaminated endoscopy equipment, it is useful to maintain a logbook that includes each patient's name and medical record number, the procedure, the endoscopist, and the serial number of the endoscope, according to APIC.

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