Awareness of how patients contract infections while in the hospital or in the course of invasive procedures is improving, as are measures to address them. (See our blog, “Controlling Staph Infections in the ICU”.) But a paper presented in June at the annual conference for the Association for Professionals in Infection Control and Epidemiology (APIC) would make anyone squeamish.
Approximately 15 in 100 gastrointestinal endoscopes used by hospitals, the research says, appear to be improperly disinfected. Endoscopes are instruments inserted to visually examine interior organs, such as the colon and stomach, to identify polyps or cancer. Duodenoscopes, gastroscopes and colonoscopes examine the duodenum (the first section of the small intestine), the stomach, and the colon, respectively.
“Three out of 20 is an unexpectedly high number of endoscopes failing a cleanliness criterion,” Marco Bommarito, Ph.D. and lead investigator, said in a news release from the APIC. “Clearly, we’d like no endoscopes to fail a cleanliness rating.”
About 15 to 20 million endoscopy procedures are performed every year.
According to the Centers for Disease Control and Prevention, more health-care associated infections have been linked to contaminated endoscopes than to any other medical device. And cross-contamination from flexible endoscopes has been identified as a primary health hazard by the ECRI Institute, an independent organization that researches patient safety and quality.
The risk to subsequent patients using dirty instruments is blood-borne infections, such as HIV and hepatitis B and C.
Just last week, a Las Vegas doctor who owned an endoscopy clinic was convicted on criminal charges, including second-degree murder, when the clinic was deemed responsible for a 2007 outbreak of hepatitis C. Although the endoscopes themselves were not specifically mentioned, the clinic, sometimes referred to as a “mill,” reused syringes and vials, and generally was in filthy condition.
The “biological dirt” found on the reusable instruments in the APIC paper includes cells and other matter left over from prior patients.
The study examined 275 instruments used at five U.S. hospitals. Thirty in 100 duodenoscopes were not clean enough, nor were 24 in 100 gastroscopes and 3 in 100 colonoscopes.
As described by the APIC, cleaning an endoscope involves two steps: first, manual cleaning with an enzymatic cleaner and flushing by a hospital technician and second, soaking the device in a high-level disinfectant. After manual cleaning, the technician visually inspects the instrument, but the new study found that contamination may be invisible to the naked eye.
After the manual cleaning, the study said, cleaning technicians were asked to flush the scopes with sterile water. That sample was analyzed by researchers for adenosine triphosphate (ATP) – a marker of bio contamination. The amount of ATP, in relative light units (RLUs), was measured with a hand-held luminometer. Based on previously published clinical data, a threshold for “pass/fail” was set at 200 RLUs. Instruments with more than 200 RLUs were deemed cleaning failures.
“The cleaning protocols for flexible endoscopes need improvement, such as guidelines tailored to the type of scope or identifying if there is a critical step missing in the manual cleaning process, and documented quality control measures,” said Bommarito. “These types of improvements could have a positive impact on patient safety.”
The APIC paper isn’t the first such negative report about insufficient instrument disinfection. Several years ago, reported AboutLawsuits.com, thousands of veterans were notified that they might have been exposed to contaminated blood during colonoscopy procedures at several Veterans Affairs hospitals because the staff had failed to clean the equipment properly.
Last year, an Air Force veteran was awarded $1.25 million from the VA because he contracted hepatitis C allegedly from a contaminated endoscope.
To learn more about infections acquired in the hospital, see our backgrounder.