HLD reduces infection risk

Ultrasound is used in almost all hospital departments and can contact intact skin, mucous membranes, non-intact skin, sterile tissue or the bloodstream. Failure to perform HLD before some of these procedures has led to outbreaks and death.

  • In 2012 a patient died from hepatitis B infection after an endocavitary ultrasound procedure where the probe was improperly reprocessed.1
  • A population-level study has established the epidemiological link between endocavitary probe low level disinfection and increased infection risk.2
  • A meta-analysis found a pooled-prevalence of 12.9% for pathogenic bacteria and 1% for pathogenic viruses on endocavitary probes after low level disinfection with use of a cover between patients.3 The probability of infection transmission of viral pathogens to patients from these procedures has been estimated to be 1-6%.4

HLD is required by Canadian national standards

The Spaulding classification specifies medical device reprocessing requirements based on the intended use of the device. This classification is used in federal guidelines (Health Canada) and national standards (CAN/CSA Z314-18).5-7

Under the Spaulding classification, semi-critical probes (e.g. endocavitary probes, external probes scanning non-intact skin) must undergo HLD with use of a sheath. Critical probes must be sterilized, however if sterilization is not possible CAN/CSA-Z314-18 permits high level disinfection.5

Observing requirements from evidence based standards is important for patient safety and is the foundation of healthcare accreditation requirements for reimbursement.

When developing policy at your facility, it is important to apply the Spaulding classification to ultrasound probes used in each type of procedure.

When to apply HLD?

  1. Medicines and Healthcare Products Regulatory Agency (MHRA). Medical Device Alert: Reusable transoesophageal echocardiography, transvaginal and transrectal ultrasound probes (transducers) (MDA/2012/037). 28 June 2012. Available at: https://assets.publishing.service.gov.uk/media/5485abf1ed915d4c0d000261/con160567.pdf
  2. Scott D, Fletcher E, Kane H, et al. Risk of infection following semi-invasive ultrasound procedures in Scotland, 2010 to 2016: A retrospective cohort study using linked national datasets. Ultrasound. 2018;26(3):168-177
  3. Leroy, S. “Infectious risk of endovaginal and transrectal ultrasonography: systematic review and meta-analysis.” J Hosp Infect. 2013;83(2): 99-106.
  4. Leroy, S., et al. “Impact of vaginal-rectal ultrasound examinations with covered and low-level disinfected transducers on infectious transmissions in France.” Infect Control Hosp Epidemiol. 2014;35(12): 1497-1504.
  5. Canadian Standards Association (CSA). CAN/CSA-Z314-18 Canadian medical device reprocessing. 2018.
  6. Health Canada. Guidance Document: Information to Be Provided by Manufacturers for the Reprocessing and Sterilization of Reusable Medical Devices. 2011.
  7. Health Canada. Guidance Document: Safety and Effectiveness Requirements for High-Level Disinfectants and Sterilants for use on Reusable Semi-Critical and Critical Medical Devices. 2018.