Is it Time to Sterilize Flexible Endoscopes?

The FDA announced earlier this year it was investigating the cause of 450 infections in patients who had undergone procedures involving urological endoscopes. The cases, which took place from January 2017 to February 2021, are chronicled in Medical Device Reports submitted to the FDA.

Inadequate reprocessing of the scopes involved in the procedures is one of the potential causes of the infections, says the FDA, which recommended high-level disinfection or low-temperature sterilization to minimize infection risks in its April letter announcing the investigations. The incidents and subsequent probes have sparked debate among experts as to which method of reprocessing the delicate instruments is best to ensure safe patient care.

Cori Ofstead, MSPH, founder and CEO of the medical research firm Ofstead & Associates, says the choice is simple. “In my view, endoscopes should be sterilized with low-temperature sterilization systems,” she says. “Urology scopes should be considered critical devices requiring sterilization because they come in contact with sterile tissue during procedures involving the bladder, ureter and kidneys.”

Urological endoscopes must be thoroughly dried before they’re sterilized, so microbial proliferation is reduced and is less than what is commonly seen in scopes that are stored after high-level disinfection. Also, sterilized scopes are packaged in ways that prevent contamination during transport and storage.“The sterilization process is more rigorous than high-level disinfection and provides a much larger margin of safety,” says Ms. Ofstead.

She believes the transition from high-level disinfection to low-temperature sterilization wouldn’t be an expensive one for facilities with low-temperature sterilization systems that employ hydrogen peroxide gas plasma, vaporized hydrogen peroxide gas, liquid chemical sterilization with peracetic acid or ethylene oxide gas.

In its April letter to healthcare facilities, the FDA says point-of-use cleaning, leak testing and manual cleaning of scopes must take place whether facilities use high-level disinfection or low-temperature sterilization. Ms. Ofstead and Alison Sonstelie, BS, CRCST, CIS, CHL, agree with the recommendation.

“Cleaning is the most critical reprocessing step,” says Ms. Sonstelie, sterile processing lead coordinator at Sanford Health in Fargo, N.D., and president of NoCoast Consulting. “It’s also the most challenging, as the cleaning process for some endoscopes involves more than 100 steps.”

Manufacturers’ instructions for use are difficult to follow and are particularly arduous for high-level disinfection. The directions for using and testing the disinfectants properly are complex, and monitoring the entire process can be time-consuming and confusing.

The sterilization process is more rigorous than high-level disinfection and provides a much larger margin of safety.
— Cori L. Ofstead, MSPH

Additionally, inadequate drying can lead to the formation of biofilm, which studies have shown present additional challenges to the high-level disinfecting process,” says Ms. Sonstelie. “This poses a risk to patient safety and can be an area of intense scrutiny during surveys by accrediting bodies.”

Overall, high-level disinfection removes all microorganisms with the exception of a relatively small number of bacterial spores. Improper cleaning will likely increase the number of spores remaining on the scope after the disinfecting process. “With proper cleaning, however, high-level disinfection can be adequate for certain lower-risk procedures,” says Ms. Sonstelie.

Low-temperature sterilization, meanwhile, kills bacterial spores. “If indicated by the device’s instructions for use, low-temp sterilization is the safest option,” says Ms. Sonstelie. “But no matter which reprocessing method is used in a facility, proper cleaning remains a critical part of the process.”

Low-temperature sterilization might actually be a better option for small ambulatory facilities, says Casey Czarnowski, BA, CRCST, CSPDT, CIS, CER, sterile processing educator at Stanford (Calif.) Health Care. The rigid sterilization containers required to house low-temp sterilized scopes require less storage space and are more durable in terms of maintaining sterility than the storage cabinets where high-level disinfected scopes are hung. Scopes in sterile containers can also be stored near the point of use, instead of a centralized scope cabinet, and transported more safely.

When considering sterilization over disinfection, workspace and inventory issues must be factored into the decision. Sterilization requires a facility to stock consumables such as sterilization locks that must be stored in accordance with the manufacturer’s IFU. These products may be new to staff, and careful training must be conducted to ensure they’re applied correctly. Sterilization containers must also be cleaned according to the manufacturer’s IFU, which require a decontamination workspace of ample size to accommodate large containers.

A facility’s workflow could also be impacted. “Most low-temperature sterilizers require instruments and containers to be completely dry before sterilization, so longer turnover times must be accepted,” says. Mr. Czarnowski.

As to whether low-temperature sterilization can be done effectively and efficiently in outpatient facilities, Ms. Ofstead says most reprocessing methods can be effective if sterile processing techs make sure scopes are free of damage and perform all required steps without delay after each procedure.

“The root of the endoscope reprocessing problem is generally that personnel cut corners because of time pressures or inadequate training and supervision,” says Ms. Ofstead. “They believe that doing things rapidly is the goal, rather than focusing on quality and safety.”

Skipping steps to shave a few minutes off the endoscope reprocessing process isn’t worth the time saved if improperly-cared-for scopes cause an infection that harms patients and is expensive for providers to treat — and potentially litigate. Ms. Ofstead notes facilities must be willing to spend what it takes to make patient care paramount, and invest in providing training and equipment to ensure scopes are cared for the right way every time. OSM

Note: This three-part article series is supported by ASP.