To reduce ultrasound probe cross infection risk, you need to know why and when to perform the high level disinfection process.
Why HLD ultrasound probes?
HLD ensures that you deliver a standard of care for patient and staff safety during ultrasound procedures while maximising compliance.
1. Deliver Patient and Staff Safety
If certain standards of care are not met, the consequences can be serious.
- Australian acute healthcare facilities encounter around 200,000 healthcare associated infections (HAIs) each year, some of which could be serious or life-threatening.1
- One of the risk factors for HAIs is the use of reusable medical devices (RMDs) like ultrasound probes that can become contaminated with micro-organisms, blood, mucous and other biological materials.2
- HAI rates can be significantly reduced by implementing effective infection prevention and control practices.1
- Inadequate cleaning and reprocessing of ultrasound probes and non-compliance with recommended reprocessing procedures may increase the risk of infection transmission and outbreaks arising from ultrasound.3
- Death has been associated with improperly reprocessed ultrasound probes.4
2. Maximise Compliance
The ASUM-ACIPC guidelines recommend HLD as the minimum standard in ultrasound reprocessing for intra-cavity ultrasound probes contacting mucous membranes as well as surface probes used in semi-critical or critical procedures (e.g. open wounds, intact infected skin, ultrasound guided interventional and surgical procedures, needle guided procedures and intra-operative uses).
Additionally these guidelines highlight automation, validation, and traceability as key features of disinfection systems for ultrasound probes as well as the use of sterile gel and sterile probe covers.3
HLD as the minimum reprocessing standard for ultrasound probes used in semi-critical procedures is also advised by the ASNZS 4187- 2014, Therapeutic goods Order 54 and NHMRC 2010 guidelines.1,2,5
ASUM-ACIPC guidelines and ASNZS 4187 standards recommend HLD between patients to reduce the risk of cross contamination. Infection-control professionals need to ensure that their internal policies are consistent with these national guidelines to ensure compliance.
“The guidelines stated that in Germany, Merz et al., like others, favours automated systems for high level disinfection, in particular devices using hydrogen peroxide (Trophon® EPR), now approved by the US Food and Drug Administration. Another important aspect of automated systems is the standardised and reproducible decontamination process thus avoiding operator-associated errors or variations. Ultraviolet (UV) light is less effective in eradicating microbes in comparison to hydrogen peroxide.”
Nyhsen CM, Humphreys H, Koerner RJ, Grenier N, Brady A, Sidhu P, et al. Infection prevention and control in ultrasound - best practice recommendations from the European Society of Radiology Ultrasound Working Group. Insights Imaging. 2017:doi: 10.1007/s13244-017-0580-3.
“Following cleaning, transducers must undergo high level disinfection (HLD) using a TGA approved instrument grade disinfection method following the manufacturer’s instructions for use (IFU).”ASUM-ACIPC Guidelines 2017
“If the transducer comes in direct contact with non-intact skin, blood or mucous membranes transducers should be cleaned with HLD irrespective of the use of a transducer cover. If transducer cover is broken during a procedure then HLD must be performed.”ASUM-ACIPC Guidelines 2017
“These devices (Semi-critical medical devices), when disinfected, must be subjected to at least a high level disinfection process with an ‘instrument grade high level disinfectant’.”Therapeutic Goods Order No. 54, 2009
GUIDELINE ALERTS – NON COMPLIANCE ISSUES
When to HLD?
HLD should be performed on ultrasound probes that are used in semi-critical procedures, as defined by the Spaulding Classification. Applying the correct level of disinfection is based on the procedure the probe is going to be used for on the next patient.
Ultrasound probes used in examinations that may have a remote chance of contacting dry/cracked skin (or other non-intact skin) and bodily fluids (including blood) should be minimally high level disinfected.3,6
If the patient is high-risk or the skin is not intact then general purpose probes should be high level disinfected.3
Heat-sensitive devices can be HLD, at a minimum, when sterilisation cannot be done due to the potential damage to the device.
High Level Disinfection (HLD):
Is one of three disinfection levels used in hospital and clinics for reprocessing ultrasound probes.
HLD results in the complete elimination of all microorganisms in or on a probe, except for bacterial spores, small numbers of which may remain.6,7
- The Spaulding Classification forms the basis for multiple US guidelines.
HLD is recommended by ASUM-ACIPC guidelines as the mimimum standard in ultrasound probe reprocessing for critical and semi-critical procedures (i.e. intracavitary and surface ultyrasound probes that contact mucous membranes or non-intact skin).
The ASUM-ACIPC, ASNZS 4187, NHMRC 2010 and Therapeutic Goods Order 54 guidelines require that a reusable medical device be properly reprocessed between patients to prevent infection, and applies the Spaulding Classification.
Ensure you comply
Following the correct probe disinfection/sterilisation requirements ensures you maintain the high standards in patient safety.
Compliance with the applicable regulatory standards is an important factor in maintaining your healthcare facility accreditation.
- Semi-critical probes should be high level disinfected even if a sheath is used6
- Critical probes should be sterilised, or can also be high level disinfected and used with a sterile sheath6
- Ultrasound probes used in examinations that may have a remote chance of contacting dry/cracked skin (or other non-intact skin) and bodily fluids (including blood) should be minimally high level disinfected3,6
- Non-intact skin includes any breakage or damage to healthy intact skin, including but not limited to dry/cracked skin, wounds, cuts, incisions, lacerations, gashes, grazes, abrasions, avulsions, eczema, rashes and burns
- If the intended use of an ultrasound probe should change prior to or during a procedure, the ultrasound probe should be reprocessed appropriately before commencing or continuing the examination
Sterilisation: All viable microorganisms must be destroyed
SEMI-CRITICAL: A device that may come into contact with intact mucous membranes and does not ordinarily penetrate sterile tissue. These devices should minimally receive HLD which is defined as the destruction of all vegetative bacteria, mycobacteria, enveloped and non-enveloped viruses, fungal spores, and some bacterial spores.6
High Level Disinfection: All viable microorganisms must be destroyed, except a small number bacterial spores
NON-CRITICAL: Devices that do not ordinarily contact the patient or contact only intact skin. These devices should be low level disinfected.
Low Level Disinfection: Most vegetative bacteria and viruses destroyed, except bacterial spores, mycobacteria, fungi, or small non-lipid viruses.
1. Australian Government/ National Health and Medical Research Council (NHMRC) Australian Guidelinesfor the Prevention and Control of Infection in Healthcare (2010). NHMRC; 2010 (https://www.nhmrc.gov.au/guidelines-publications/cd33).
2. Standards Australia/Standards New Zealand. AS/NZS 4187:2014 Reprocessing of reusable medical devices in health service organizations (superseding AS/NZS 4187:2003). Standards Australia; 2014.
3. ACIPC-ASUM. Guidelines for Reprocessing Ultrasound Transducers. Australasian Journal of Ultrasound in Medicine. 2017;20(1):30-40.
4. GOV.UK Medical Safety Alert; Reusable transoesophageal echocardiography, transvaginal and transrectal ultrasound probes (transducer) – failure to appropriately decontaminate. (https://www.gov.uk/drug-device-alerts/medical-device-alert-reusable-transoesophageal-echocardiography-transvaginal-and-transrectal-ultrasound-probes-transducers-failure-to-appropriately-decontaminate).
5. Therapeutic Goods Order No. 54B. Standard for Disinfectants and Sterilants (Amendment to Therapeutic Goods Order No. 54). Therapeutic Goods Act 1989; 2009 (https://www.legislation.gov.au/Details/F2009C00327).
6. Rutala WA, Weber DJ, HICPAC. Guideline for Disinfection and Sterilization in Healthcare Facilities. USA: Centers for Disease Control; CDC 2008. (http://www.cdc.gov/hicpac/Disinfection_Sterilization/acknowledg.html).
7. Federal Drug Administration. Guidance for Industry and FDA Reviewers: Content and Format of Premarket Notification [510(k)] Submissions for Liquid Chemical Sterilants/High Level Disinfectants. 2000.