The U.S. Food and Drug Administration published suggested reprocessing methods for duodenoscopes, to be implemented in conjunction with manufacturers’ recommendations.
The suggestion, published in an FDA Safety Communication in August, followed earlier reports of injuries and deaths attributed to inadequate reprocessing of duodenoscopes. Those reports led the FDA in February 2015 to publish a warning to healthcare providers and the public that even the most meticulous attention paid to cleaning and disinfecting the scopes may not be enough to protect patients from infection passed on by other users. One month later, in March, the Centers for Disease Control and Prevention issued an interim protocol for facilities that want to test their duodenoscopes for contamination with bacteria after cleaning and disinfection.
Duodenoscopes are flexible, lighted tubes that are threaded through the mouth, throat, and stomach into the top of the small intestine (duodenum). They are used in more than 500,000 procedures, called endoscopic retrograde cholangiopancreatography – or ERCP – in the United States each year, according to the FDA. ECRP is said to be the least invasive way of draining fluids from pancreatic and biliary ducts blocked by tumors, gallstones or other conditions.
Duodenoscopes are complex instruments, which contain many small working parts, according to the FDA. Proper cleaning and disinfection of the elevator mechanism is of particular concern. The moving parts of the elevator mechanism contain microscopic, hard-to-reach crevices. If not thoroughly cleaned and disinfected, tissue or fluid and residual bacteria from one patient may remain in device crevices of a duodenoscope, exposing subsequent patients to risk of infection.
Reprocessing measures
Hospitals and healthcare facilities that use duodenoscopes can, in addition to meticulously following manufacturer reprocessing instructions, take one or more of the following additional steps to further reduce the risk of infection and increase the safety of duodenoscopes:
- Microbiological culturing. Microbiological culturing involves sampling duodenoscope channels and the distal end of the scope and culturing those samples to identify any bacterial contamination that may be present on the scope after reprocessing. Some facilities have successfully implemented routine or periodic surveillance culturing to assess the adequacy of duodenoscope reprocessing and to identify duodenoscopes with persistent contamination despite reprocessing.
- Ethylene oxide (EtO) sterilization following cleaning and high-level disinfection. At a minimum, as per the manufacturer’s instructions, duodenoscopes should be subjected to high-level disinfection following manual cleaning after each use. When possible and practical, duodenoscopes should be sterilized, due to the greater margin of safety provided by sterilization. Since it does not rely on heat, EtO gas sterilization may be an effective method for heat-sensitive instruments, such as duodenoscopes, which can be damaged by high temperatures, according to the FDA.
- Use of a liquid chemical sterilant processing system following cleaning and high-level disinfection. A liquid chemical sterilant (LCS) processing system is a device that uses a chemical solution to destroy all viable forms of microbial life. Notably, because this process requires rinsing with highly purified (but not sterile) water following device sterilization, the device does not remain completely free of all viable microbes, says FDA. The concentration, exposure time and temperature of a liquid chemical sterilant are crucial, because inappropriate dilution, insufficient exposure, or inadequate temperature may result in ineffective reprocessing outcomes.
- Repeat high-level disinfection. Because a small number of duodenoscopes may have persistent microbial contamination despite reprocessing, some healthcare facilities have implemented repeat high-level disinfection (HLD) after the first HLD cycle in their duodenoscope reprocessing procedures, either manually or through the use of automated endoscope reprocessors (AERs), according to FDA. HLD involves immersing the device with a disinfectant and is expected to inactivate all microorganisms except for large numbers of bacterial endospores. AERs are devices that wash and high-level disinfect endoscopes and scope accessories to decontaminate them between uses. AERs are designed to expose outside surfaces and interior channels of endoscopes to chemical solutions in order to kill microorganisms.
FDA says that it recognizes that not all healthcare facilities can implement one or more of these measures, which require specific resources, training, and expertise. Therefore, it is critical that staff responsible for reprocessing duodenoscopes have the manufacturer’s instructions readily available to promote strict adherence to the reprocessing instructions in the device labeling, understand the importance of their role in reprocessing the device, and maintain proficiency in performing these reprocessing tasks.
To view the FDA Safety Communication, go to http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/ucm454766.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery