I recently completed a fascinating one-hour course offered by Ofstead & associates that discussed insoluble substances inside endoscope after use. Infant gas relief drops, Gas-X, Mylanta Gas and other products that contain simethicone are inserted in the biopsy channel when there is trouble seeing due to bubbles or foam. These products contain silicone or simethicone which is an anti foaming agent. The use of these products aid seeing when foaming interferes with a colonoscopy.

The problem for reprocessing endoscopes with simethicone is that it is insoluble in water, detergent and alcohol. Simethicone will actually repel water, making removal from biopsy or water channels very difficult. This represents a very real problem when reprocessing endoscopes because any remaining silicone is a potential contaminant that can infect subsequent patients. It is possible to remove the droplets of simethicone by locating the droplets and using swabs. The borescope can then be used to verify the removal of the substance.

The course also discusses how Tissue glue may also be found inside the channels of colonoscopes. If tissue glue is allowed to harden in the working channel it may not able to be removed. The working channel may become blocked and require repair of the instrument. I was also surprised to learn that the use of cooking spray has a lubricant inside working channels is another source of simethicone (silicone) residue. The oils residue can be cleaned using hot water and detergent the simethicone still remains a problem.

This was a very revealing course that exposes many of the issues faced when reprocessing endoscopes. It also reinforces the need to use a borescope to inspect the lumens and channels of endoscopes. I recommend that anyone involved in the reprocessing of endoscopes take the time to learn from this webinar.

All endoscope lumens need to be visually inspected after cleaning to locate residual material that remains. The fact that simethicone is found inside endoscope lumens after cleaning makes a strong case for a visual inspection program center around the use of borescopes. Visually inspecting endoscope lumens after cleaning can prevent future infections. If any residual material remains in an endoscope lumen swabs should be used to remove the material. Brushes and water will typically not aid in removing simethicone. This process should be repeated until the lumen can verified to be clean with the aid of a borescope.