infection prevention
infection prevention
By Daniel Merton , BS , RDMS , FAIUM , FSDMS
Ultrasound Technologies and IP & C : Balancing Appropriate Disinfection , Workflow and Manufacturer Recommendations
The use of diagnostic ultrasound imaging is rapidly growing in conventional settings , such as radiology and cardiology , as well as for a wide range of point of care ultrasound ( POCUS ) applications . The use of non-ionizing radiation allows ultrasound to be used on the most vulnerable of tissues such as the fetal brain , and structures in the eye , and permits its use when and where other imaging modalities cannot . While the clinical value of ultrasound imaging is well known , use of the modality can also present the potential for patient harm , most notably cross contamination leading to infection .
Regardless of whether it ’ s a premium cart-based scanner used in a maternal-fetal medicine setting , a handheld wireless probe used for a quick assessment of a patient ’ s lungs in the emergency department , or a portable scanner used to guide vascular access in the ICU , safe use of ultrasound devices demands appropriate and effective reprocessing . Ultrasound professionals ( e . g ., sonographers , echocardiographers ) are expected to be familiar with the processes used to clean and disinfect the equipment they use , but many “ new users ’” of POCUS may not recognize the importance and particulars of properly reprocessing ultrasound devices – especially transducers ( AKA probes ). Some recent advances , such as touchscreens and sealed user interfaces , facilitate reprocessing , while others , such as probes that wirelessly connect to a smartphone for data display , pose additional infection prevention concerns , particularly if a clinician uses their personal smart device for POCUS applications .
Dr . Earle Spaulding , a microbiologist at Temple University in Philadelphia , classified reuseable medical devices as critical , semi-critical , and non-critical based on the potential risk of patient infections from their use , and defined the required level of disinfection to minimize risk . 1 Spaulding also classified levels of germicidal effectiveness as low-level disinfection ( LLD ), high-level disinfection ( HLD ) and sterilization . Several organizations and professional societies including the American Institute of Ultrasound in
Regardless of whether it ’ s a premium cart-based scanner used in a maternal-fetal medicine setting , a handheld wireless probe used for a quick assessment of a patient ’ s lungs in the emergency department , or a portable scanner used to guide vascular access in the ICU , safe use of ultrasound devices demands appropriate and effective reprocessing .”
Medicine ( AIUM ), Society of Diagnostic Medical Sonography ( SDMS ), and ECRI have published guidelines and recommendations pertaining to reprocessing ultrasound devices based on the Spaulding scheme . 2-4 When applied to ultrasound probes , the Spaulding categories are noncritical ( e . g ., transducers that only contact intact skin ), semi-critical ( e . g ., probes that come in contact with mucosal surfaces and probes used to scan near open wounds ), and critical ( e . g ., probes used in sterile body cavities such as laparoscopic ultrasound probes , intracardiac echocardiography ( ICE ) catheter probes and robotic “ drop-in ” probes ). More detailed information can be found in the references .
Vendors of ultrasound equipment are required to validate reprocessing products and processes for their scanners and probes as part of the FDA 510 ( k ) clearance requirements . 5 Device instructions for use ( IFUs ) include information regarding the approved cleaning and disinfection products and recommended procedures . The lists of approved products can be quite extensive , are frequently updated as new products become available , and it can sometimes be challenging to identify an approved product to use on a given transducer . The need to use vendor approved products can be particularly onerous for facilities that have ultrasound equipment from multiple vendors and their inventory includes many types of probes . Vendors base their recommendations on the intended clinical application of the probe – for example a probe used to perform abdominal or obstetric sonograms , and considered a non-critical device typically requires cleaning and LLD , which can be performed using a vendor-approved disinfectant wipe . However , a probe used to perform an endovaginal gynecologic ultrasound exam requires cleaning and HLD , which is more labor intensive and time consuming than LLD .
Note that the Spaulding system calls for sterilization of semi-critical devices such as endovaginal ultrasound probes , but HLD is commonly used as a chemical sterilant because most probes cannot undergo heat sterilization . Vendor approved products have been verified to be both biologically effective and not detrimental to device surfaces . Thus , it is important for users to follow a vendor ’ s reprocessing recommendations or risk ineffective disinfection , damage to the probe and possibly voiding the warranty . While vendors provide recommendations , it remains the responsibility of the user to choose appropriate cleaning and disinfection products based on the exam performed and facility policies .
Unfortunately , reprocessing recommendations from different sources are not always consistent , which can lead to uncertainty and inconsistency in reprocessing . For example , the 2021 Intersocietal Position Statement titled “ Disinfection of Ultrasound Transducers Used for Percutaneous Procedures ” indicates ultrasound probes that are covered by a sterile sheath and used in percutaneous interventional procedures , such as biopsies and vascular access guidance , require cleaning and LLD between use . 6 This updated recommendation has been embraced by some users , such as vascular access ( VA ) teams who perform numerous ultrasound guided VA procedures every day . The previous recommendation of HLD for these devices was time and labor intensive , which adversely impacted workflow . However , this change has not been universally accepted and adopted .
10 • www . healthcarehygienemagazine . com • june 2024