HIDDEN MENACE Could biofilm — a slimy microscopic coating that harbors bacteria — be hiding in your lumened instruments?

Biofilms are a reprocessor's nightmare. Resilient, relentless and often microscopic, these slimy, sticky coatings that bacteria excrete can form in minutes on moist surfaces and in lumened instruments. Once they form, good luck removing them. Biofilms can be up to 1,000 times more resistant to antimicrobial agents than the standard bacteria you're used to fighting. But there are steps you can take to prevent biofilm from forming.

• Point-of-use cleaning. The longer biofilm sits on instruments, the stronger it becomes and the harder it is to remove. Begin the cleaning process as soon as possible after instruments have been used. After you wipe and rinse away all gross, heavy organic debris and flush cannulas with sterile water, keep instruments moist. You can spray them with an enzymatic solution or foam, cover them with a moist towel, or place them in a plastic bag or pouch. Don't let moist instruments sit for too long. The conditions for biofilm to form are perfect when bacteria remain in a wet environment for a long time. Then it becomes even more difficult to get your instrument microbe-free.
• Transport to central sterile. After point-of-use cleaning is complete, promptly transport instruments to central processing in a covered container. New AORN guidelines state that OR staff should document when the procedure ended so techs know how much time has elapsed between the end of the procedure and the start of cleaning.
• Cleaning. This step depends on the instrument and the manufacturer's instructions for use (IFU). Follow these instructions exactly to ensure thorough cleaning. Depending on the type of instrument, this might include manual cleaning, ultrasonic washing or using an automated washer. If allowed by the IFU, mechanical cleaning is preferred over manual scrubbing because it's more thorough and less variable, according to some endoscope reprocessing guidelines (osmag.net/oVrP6X).

When you manually clean, lumen-flushing devices, pull-through brushes and other endoscopic cleaning aids may boost the tech's effectiveness during scrubbing. Detergents have a difficult time penetrating biofilm colonies, so typically you'll need to scrub any observed biofilm with a brush and detergent several times. No studies show that one particular detergent is better than another at removing biofilm.

• Sterilization and/or high-level disinfection. Following the IFUs, it's time to sterilize or high-level disinfect the instrument after cleaning. If a biofilm has formed and survived cleaning, sterilization or high-level disinfection methods — including steam, ethylene oxide, and gas plasmas like hydrogen peroxide or ozone — might not kill the microbes the biofilm's slimy coating are protecting, potentially leading to cross-contamination. That goes for both high-level disinfection and all sterilization.

MOIST, ENCLOSED SPACES
Where's Biofilm Likely to Form?

CHANNELS AND TIPS Endoscopes are particularly at risk of developing biofilm.

Biofilm often grows in the enclosed spaces and lumens of medical devices that are difficult to clean and dry properly. The lumen channels and tips of inadequately decontaminated endoscopes are particularly susceptible to biofilm, but it can form on all surgical instruments and medical devices, and on most materials, including plastic, metal and even human tissue. In addition to endoscopes, instruments with at-risk designs include laparoscopic, arthroscopic and complex orthopedic instruments with cannulas (like depth gauges). Patients who undergo endoscopy or surgery with a biofilm-containing device are at risk for infection.

— Donna Swenson, BS, CRCST, CH

You're not done yet
Even after you've cleaned and sterilized/high-level disinfected the device, you're not done yet. Biofilm can grow on instruments even if you strictly follow the manufacturer's IFUs for cleaning. You must verify that the instrument is free of microbes and then properly store it.

• Verification. Don't just follow the reprocessing steps. Verify that the cleaning process worked by testing and inspecting devices for cleanliness.

Though there are no tests available outside of the laboratory to check for biofilm specifically, many post-cleaning verification tests ensure that there's no organic debris left on the device. Some tests, for example, will show the presence of protein, hemoglobin and/or adenosine triphosphate (ATP) on devices. To use these tests, you swab the instrument after cleaning and then either insert the swab into a handheld machine to test for bioburden, or into a solution that changes colors if organic debris is detected.

Your techs should also visually inspect the device for cleanliness. If the device is contaminated, they must repeat the entire cleaning process.

Also monitor mechanical equipment in your processing department to ensure it's in good working order. Some tests ensure that ultrasound cells in ultrasonic washers are functioning, others demonstrate that automated washers are effectively removing soil. Techs should perform these tests regularly, according to the machines' IFUs.

• Storage. Be careful with how you store the device, since biofilm can easily grow if you let moisture collect in the lumens and channels. For endoscopes, drying cabinets that circulate HEPA-filtered air and force air through the scope's channels can help prevent moisture and the growth of biofilm.

For surgical instruments, it's expected that the tray's blue wrap or covered container will keep the instruments sterile and ready for use after sterilization. But if you see any sign of moisture on the outside or inside of the container or wrap, consider the package contaminated and reprocess the instruments. To help prevent this, let instruments adequately cool after sterilization and before you move them from the sterilizer cart. If you move devices while they're still warm, condensation can occur and cause the devices in the sterile pack to become contaminated. OSM