The endoscopes were used over a three-year period between 2012 and Dec 2014 at the University Hospital of Northern B.C.
The procedures included colonoscopies, upper gastric scopes, and endoscopic retrograde cholangiopancreatogram (ERCP) exams
Ronald Chapman, the vice president of medicine with Northern Health said the problem occurred during the pre-cleaning of the instrument.
"Generally, when an endoscope is used, the physician or the nurse who used the scope is responsible for doing the pre-cleaning to remove any tissue or fluid from a narrow air and water channel."
Chapman said the manufacturer's instructions say that a narrow channel in the instrument must be rinsed out for 30 seconds before cleaning.
"What some of the staff did is that, the button was pressed, but it wasn't normally held for 30 seconds, nor did the air suction get reliably applied for 10 seconds. This was the step incorrectly applied by our staff."
Extremely low infection risk
Chapman said improperly cleaned endoscopes could cause hepatitis B and C and HIV infection, but in this case, the B.C. Centre for Disease Control has determined that risk of infection is extremely low.
Between 2012 and last month, there is no evidence a single infection arose from use of the endoscopes, he said.
Northern Health will be contacting patients who have had one of the procedures during the time frame, and their physicians, to provide them with additional information.
"We would particularly like to apologize for any undue stress, especially ... for our patients," he said.
The error did not impact the diagnostic outcome of the tests, he said.
People with immediate concerns can contact 1-844-565-5516 or firstname.lastname@example.org.
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