With the number of ultrasound procedures increasing every year in the United Kingdom, the exponential risk factor of cross-contamination infection between patients increases.
The concern about patient crosscontamination due to incorrect ultrasound reprocessing is supported by a groundbreaking population-led study undertaken by Health Protection Scotland and NHS National Services Scotland.1
The first-of-a-kind study was released in 2017 and documents results collected between 2010 and 2016. It demonstrates a greater risk of positive microbiological reports and antibiotic prescriptions within 30 days for adults who had undergone semi-invasive ultrasound procedures when high level disinfection was not used as standard of care.1
During the study period, (before high level disinfection was recommended as standard in 2016), low level disinfection was the primary method used for the disinfection of endocavitary probes.
In relation to transvaginal ultrasound scans, the study found that in the 30 days after a scan, patients were 41% (HR=1.41) more likely to have positive bacterial cultures and 26% (HR=1.26) more likely to be prescribed antibiotics than similar patients who underwent gynaecological procedures without ultrasound (p<0.001).
For transrectal scans, patients were 3.4 (HR=3.4) times more likely to have positive bacterial cultures and 75% (HR=1.75) more likely to be prescribed antibiotics (p<0.001).
The study concluded: “Analysis of linked national datasets demonstrated a greater risk of positive microbiological reports and community antibiotic prescriptions within 30 days for Scottish adults who had undergone semiinvasive ultrasound procedures in Scotland. This indicates that, prior to the publication of NHS Scotland guidance advocating high level disinfection, the re-use of semi-invasive ultrasound probes without high level disinfection posed an increased risk of infection… failure to comply with guidance recommending high-level disinfection of semi-invasive ultrasound probes will continue to result in an unacceptable risk of harm to patients.”
Commenting on the Scottish study, Claire Manning-Jones, decontamination lead, critical care, theatres, anaesthetics, pain and sleep, Leicester Royal Infirmary, said: “This is an important publication for a decontamination lead as this documents a risk and the reasoning why there is a need for the ultrasound probe to be high level disinfected. This also provides the evidence for the clinicians to embrace the change to the way we are disinfecting our probes.
“The Health Protection Scotland and NHS National Services Scotland study was very valuable as it supported what many of us had suspected about cross-contamination risks and had been concerned about. We have guidelines in place to ensure best practice standards but sometimes pressurised workflows and human error can be a factor in incorrect reprocessing. This can be avoided by using an automated high level disinfection solution as referenced in local and international reprocessing guidelines. Whatever solution is chosen, it’s important that it complies with guidelines, is a validated process that provides evidence for audit, and does not interfere with our busy workloads.”
Traceability is key to best practice standards
To reduce the risk of ultrasound probe crossinfection, it’s not enough that relevant probes should be high level disinfected. The disinfection system must also offer a compliant traceability system.
According to various United Kingdom guidelines, including the updated joint Society & College of Radiographers and the British Medical Ultrasound Society recommendations, traceability refers to the documentation collected to link medical devices and their reprocessing parameters with patient use.2,3,4,5 The correct recording of information is important, especially in the event of infection outbreaks.
United Kingdom Health Technical Memorandums also require that records pertaining to cleaning, disinfection, patient use, operator, as well as records relating to qualification and validation are maintained, preferably via an automated system.3,4
Taking all these operational considerations into account is trophon2, the latest innovation for high level disinfection from Nanosonics (the creator of trophon EPR).
Bryn Tudor-Owen, Nanosonics country manager for UK and Ireland said: “With trophon2, Nanosonics has gone further in providing the world’s most advanced ultrasound high level disinfection solution in a closed door system offering smarter protection, flexibility, functionality, traceability and integration.”
He added: “We have listened to what sonographers need to do their important work and the majority wanted an improved traceability function. As a result, one of the central and most valued features is trophon2’s AcuTrace™ traceability capability. Sonographers no longer have to rely on their hand written notes to create disinfection records.”
Instead, the record keeping process offers digital traceability and documentation of disinfection cycles. trophon2’s ultrasound probe tags, operator cards, disinfectant cartridges and chemical indicators contain RFID (Radio Frequency Identification) chips that store digital information. Additionally, correct storage of ultrasound probes after high level disinfection is a crucial reprocessing step and this can be achieved by using trophon Clean Ultrasound Probe Covers. These covers protect ultrasound probes from recontamination while being transported to and from storage areas, or placed in the ultrasound device holders visually indicating they have been high level disinfected and ready to be used on the next patient.
As the sonographer steps through the ultrasound probe reprocessing workflow, supported by animated visual instructions on a colour touch screen, the built-in AcuTrace reader automatically captures and stores the disinfection cycle data on to the trophon2 device for complete records. This results in improved compliance with required standards.
The information can be downloaded on to a USB for record keeping, or the last disinfection cycle can be reviewed onscreen. Labels can also be printed out and placed on a Clean Ultrasound Probe Cover, another in the patient’s medical records, or the serial and cycle numbers can be recorded into the patient’s Electronic Medical Record.
The optional AcuTrace PLUS software enables trophon2 to be integrated into a hospital IT system so all data can be stored and accessed centrally. Electronic Disinfection Records can be linked directly to Electronic Patient Records for future reference.
Comprehensive patient protection
The trophon family consists of trophon2 and trophon EPR. Nanosonics has conducted extensive testing to validate the effectiveness of trophon against a wide variety of microorganisms.
Tudor-Owen added: “Patient safety and reducing the risk of infection spread is paramount to us and drives our clinical research and testing. Going far beyond the minimum regulatory requirements, we prioritise having the broadest possible microbial efficacy programme.”
Furthermore, in a closed chamber, trophon inactivates the mandated subset of microorganisms as required by European Standards, as well as eliminating an extended range of infectious pathogens including those that cause sexually transmitted infections, drug resistant bacteria and high numbers of bacterial spores (Clostridium difficile), of which a small number are permitted to remain.
Importantly, trophon2 complies with reprocessing guidelines issued by Health Facilities Scotland, NHS Wales, Ireland’s Health Services Executive, The Society & College of Radiographers and the British Medical Ultrasound Society, and the European Society of Radiology.2-6 These guidelines state the preference for an automated high level disinfection system for the reprocessing of semi-critical ultrasound probes, semi-invasive and non-invasive ultrasound probes.
Confusion about when to use high level disinfection
Tudor-Owen believes there is an element of confusion about when to high level disinfect ultrasound probes. “It’s not only endocavitary probes that should be high level disinfected before a procedure but also surface probes,” he asserted.
“The simplest way of explaining this is to refer to the Spaulding Classification which defines the disinfection requirements for medical devices, including ultrasound probes.”
The classification states that for the semi-critical category (medical devices), high level disinfection is required for probes that may come into contact with mucous membranes and non-intact skin. This occurs during transvaginal and transrectal scans using intracavitary probes. Surface probe procedures include wound scanning and probe guided wound assessment and probe guided cannulation/venepuncture procedures.
For the critical category (medical devices), high level disinfection is required for probes that may contact sterile tissue or blood. Procedures include intraoperative, drainages, biopsies, needle guidance, transvaginal oocyte retrieval, venous catheter placement and vascular access.
Becoming standard of care
Currently trophon can be found in nearly 100 health facilities in the United Kingdom, including seven of the top 20 hospitals in England and Wales (based on staffing size). trophon2’s compact size and the added advantage of a closed disinfection chamber, makes it ideal for point of care use, offering improved cost and workflow efficiencies. From an operational perspective, trophon is compatible with more than 1,000 probe models from all major and many smaller ultrasound probe manufacturers. What’s more, trophon’s sonicated ultrafine hydrogen peroxide mist reduces exposure to traditionally harsh chemicals.
Finance options are available
Whatever your facility’s budget, Nanosonics has different financing options to suit. To find out more, please call 01484 860581.
Nanosonics UK
Unit 2, Linfit Court, Colliers Way Clayton West, Huddersfield West Yorkshire HD8 9WL United Kingdom
Tel: 01484 860581
Web: www.nanosonics.co.uk
Email: ukinfo@nanosonics.co.uk
References for this article are available upon request.
