Ew, Gross: Reusable Endoscopes Are Not Clean

Yeesh. After surveying 275 reusable gastrointestinal endoscopes from U.S. hospitals, researchers found that 15 percent aren’t up to cleanliness standards.

Gastrointestinal endoscopes carry cameras into the small intestine, stomach or colon, to help doctors examine those areas. As you can imagine, they get pretty dirty. If they’re not well cleaned, they can transmit microbes and other biological matter between people.

Researchers from the technology company 3M gathered endoscopes from five U.S. hospitals. They found different numbers of substandard cleaning for different types of scopes. Thirty percent of endoscopes designed to go into the small intestine weren’t cleaned to standard. Twenty-four percent of endoscopes designed to go into the stomach had the same problem. Scopes for the colon fared the best, with only 3 percent hitting below standard.

Scientists have long known that clean endoscopes are a problem in hospitals. A 2008 report from the U.S. Centers of Disease Control and Prevention found that while the numbers of reported infections from contaminated endoscopes were low–one in 1.8 million endoscopy procedures causes infections–the scopes were still the number-one medical device associated with hospital infection outbreaks. The same report found that following strict rules on how to clean endoscopes works well, but technicians don’t always follow the rules.

In general, technicians are supposed to follow several steps when they clean endoscopes. They first scrub and flush the devices, using water and a detergent. Then they soak the scopes in a disinfectant for however long the disinfectant maker suggests. Finally, they rinse the scopes with water and alcohol and dry them quickly, to prevent them from getting recontaminated by microbes present in water.

The Centers for Disease Control and Prevention don’t mention a standard for measuring whether a cleaned endoscope is really clean. The 3M researchers used a benchmark that other studies have used, based on ATP, an enzyme that all cells have. A properly cleaned scope should have less than 200 light matter units of ATP on it. One previous study found that before cleaning, the exteriors of scopes have, on average, more than 10,000 light matter units of ATP.

The 3M researchers are presenting their survey today at a conference for infection control specialists.