Reprocessing of Reusable Ultrasound Transducer Assemblies Used for Biopsy ProceduresJun 19, 2006 Dear Colleagues:
This is to alert you to the importance of properly cleaning and sterilizing reusable ultrasound biopsy transducer assemblies (i.e., transducer device and associated accessories), and to provide recommendations for doing so. If these devices are not correctly reprocessed between patients, residual material from a previous patient may contaminate the biopsy needle and needle guide when the system is reused for biopsies. This could lead to patient infections.
On April 3, 2006, the Department of Veterans Affairs (VA), Veterans Health Administration issued a Patient Safety Alert related to a particular company's ultrasound transducer assemblies. During patient safety rounds, the lumen of a needle guide of an ultrasound transducer assembly was found to be soiled. The alert provided recommendations on reprocessing that brand of transrectal ultrasound transducer, which is widely used throughout the VA. FDA is issuing this notification as a supplement to the VA alert because we believe inadequate reprocessing procedures may be a problem for all invasive ultrasound transducer assemblies.
Health care professionals use ultrasound transducer assemblies to view body structures and obtain biopsy samples under ultrasonic guidance. To facilitate biopsy, these devices may have a needle guide attached that directs the insertion of a biopsy needle. The procedure often involves placing the transducer in a body cavity where contact with blood, other body fluids, or feces is likely. During this procedure, the transducer assembly should be covered with a sterile barrier sheath (e.g., a condom). It is important to follow the manufacturer’s labeling with regard to the use of sterile covers for each particular device in order to reduce the risk of patient infection.
Insertion of the biopsy needle is often repeated through the guide. Since a biopsy needle contacts the needle guide before it penetrates sterile tissue for biopsy, the needle and needle guide should be reprocessed as critical devices. * The biopsy needle and its containing guide must always be sterilized. This should apply even if a sterile barrier sheath is used on the transducer assemblies during a biopsy procedure, as the sheath is compromised by the penetration of the needle.
[Critical devices require sterilization between patients unless they cannot withstand the rigors of sterilization. In these cases only, high level disinfection can suffice for the parts that cannot be sterilized. Definitions for critical device, semi-critical device, high-level disinfection, and sterilization available at: ANSI/AAMI ST58:2005, Chemical Sterilization and High-Level Disinfection in Health Care Facilities. http://www.aami.org].
The importance of cleaning
For any reprocessing method to be effective, the reusable device must be thoroughly cleaned before it is subjected to the sterilization process. Brushes should be used, when required, to effectively clean the transducer assemblies, especially the lumens. Failure to brush needle guide lumens has resulted in improper reprocessing, and may have been associated with the transmission of patient infections. We have received reports of visible residue in the biopsy needle-guide channels of some patient-ready reusable transducer assemblies.
If your transducer assembly kits are not supplied with brushes, ask the manufacturer for all relevant specifications for the appropriate brush and a source(s) for purchase of these brushes.
It is also essential to use appropriate detergents for cleaning and enzymatic cleaners for removing proteins from the transducer assemblies. Refer to the manufacturer’s instructions for information on compatible detergents and cleaners.
In order to avoid reprocessing problems, it is critical that you follow the manufacturers’ instructions for reprocessing these transducer assemblies. The operators manuals/user guides for these transducers should give detailed instructions for cleaning and sterilization for each specific brand and model of device, and specify the equipment and supplies needed to correctly reprocess the assemblies. These reprocessing instructions have been validated by the manufacturer. Sterilization processes that are recommended by the transducer manufacturer should be used. Steam sterilization or liquid chemical high level disinfection is to be used as recommended by the transducer assembly manufacturer. If there is anything in the manufacturer’s instructions that is not clear, contact the manufacturer for clarity. Make no assumptions.
Remember, you can not achieve sterilization or high-level disinfection unless the assembly is cleaned first.
When cleaning and sterilizing re-usable ultrasound transducers, be sure to:
- Disassemble the transducer assembly parts for cleaning.
- Use a clean and properly-sized brush for each lumen of the device that is being cleaned.
- Thoroughly clean all surfaces of reusable components.
- Brush and thoroughly rinse the channels through which the biopsy needles pass and any areas where the needle guide passes through the transducer to loosen materials inside the lumens, and check to be sure that no visible soil remains.
- Thoroughly examine all surfaces that have been cleaned and visually inspect the ENTIRE device to make sure it is clean.
- Steam-sterilize all heat-stable, reusable components after each use. If using automatic reprocessing equipment, be sure to utilize the proper connections to the transducer assemblies.
- Use a liquid chemical high-level disinfectant ONLY for heat-sensitive components that cannot withstand steam sterilization. Be sure to flush any lumens or channels with the disinfectant to ensure that the disinfectant reaches all areas inside the lumens.
- Always use sterile water for rinsing or removing residual germicides from devices which have been processed using liquid chemical germicides. Do not rinse reprocessed devices with tap water, which may recontaminate the device.
- Thoroughly dry the device after rinsing with sterile water.
- Do not reuse or reprocess items labeled for single-use (e.g., single-use biopsy needles), which have not been validated for reprocessing.
- After sterilization, appropriately package and store the device or component to ensure that sterility is not compromised prior to reuse.
Reporting to FDA
FDA requires hospitals and other user facilities to report deaths and serious injuries associated with the use of medical devices. If you suspect that a reportable adverse event was related to the use of an ultrasound transducer assembly, you should follow the reporting procedure established by your facility.
We also encourage you to report adverse events related to ultrasound transducers used for biopsy procedures that do not meet the requirements for mandatory reporting. You can report these directly to the device manufacturer. You can also report to MedWatch, the FDA’s voluntary reporting program. You may submit reports to MedWatch by phone at 1-800-FDA-1088; by FAX at 1-800-FDA-0178; by mail to MedWatch, Food and Drug Administration, 5600 Fishers Lane, Rockville, MD 20852-9787; or online at http://www.fda.gov/medwatch/report.htm.
Getting More Information
If you have questions about this notification, please contact the Office of Surveillance and Biometrics (HFZ-510), 1350 Piccard Drive, Rockville, Maryland, 20850, Fax at 240-276-3356, or by e-mail at firstname.lastname@example.org. You may also leave a voice mail message at 240-276-3357 and we will return your call as soon as possible.
FDA medical device Public Health Notifications are available on the Internet at http://www.fda.gov/cdrh/safety.html. You can also be notified through e-mail each time a new Public Health Notification is added to our web page. To subscribe to this service, visit: http://service.govdelivery.com/service/subscribe.html?code=USFDACDRH_10.
Daniel Schultz, MD
Center for Devices and Radiological Health
Food and Drug Administration