Surface probes have diverse applications and are used in over 70 different interventional procedures across all hospital departments. In some procedures, surface probes risk contacting nonintact skin, sterile tissue or the bloodstream. Examples include intraoperative probes and probes used to guide biopsies, drainages or injections. Like endocavitary probes, surface probes require high level disinfection (HLD) based on their use.

Ultrasound guided procedures can transmit infection

  • Surface probes used in emergency and critical care settings can be heavily contaminated. In a study across five emergency departments and five intensive care units, 57% of probes had blood contamination and 46% had microbial contamination.1
  • Sixty percent of transabdominal probes surveyed at a public hospital and a private practice had evidence of bacterial contamination after an ultrasound procedure.2
  • Outbreaks have resulted from ultrasound guided procedures, determined by isolating a common organism from the patient and the ultrasound transmission gel. Patients developed bloodstream infections following central line placements, with one of the outbreaks involving patient death.3,4
  • Another study documented a Mycobacterium massiliense outbreak in 40 patients over 3 years which was also linked to gel used in ultrasound guided invasive procedures. Procedures involved in the persistent outbreak included ultrasound guided amniocentesis, pericardiocentesis and arthrocentesis.5

When to HLD surface probes

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).6-8Under the Spaulding classification, semi-critical probes (e.g. probes scanning broken 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.6

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


  1. Keys M, Sim BZ, Thom Ogilvie, et al. Efforts to Attenuate the Spread of Infection (EASI): a prospective, observational multicentre survey of ultrasound equipment in Australian emergency departments and intensive care units. Crit Care Resusc. 2015;17(1): 43-46
  2. Westerway SC, Basseal JM, Brockway A, et al. Potential Infection Control Risks Associated with Ultrasound Equipment – A Bacterial Perspective. Ultrasound Med Biol. 2017;43(2):421-6.
  3. Shaban RZ, Maloney S, Gerrard J, et al. Outbreak of health care-associated Burkholderia cenocepacia bacteremia and infection attributed to contaminated sterile gel used for central line insertion under ultrasound guidance and other procedures. Am J Infect Control. 2017;45(9):954-58.
  4. Abdelfattah R, Aljumaah S, Alqahtani A, et al. Outbreak of Burkholderia cepacia bacteraemia in a tertiary care centre due to contaminated ultrasound probe gel. J Hosp Infect. 2018;98(3):289-94.
  5. Cheng A, Sheng WH, Huang YC, et al. Prolonged postprocedural outbreak of Mycobacterium massiliense infections associated with ultrasound transmission gel. Clin Microbiol Infect. 2016;22(4):382. e1-e11.
  6. Canadian Standards Association (CSA). CAN/CSA-Z314-18 Canadian medical device reprocessing. 2018.
  7. Health Canada. Guidance Document: Information to Be Provided by Manufacturers for the Reprocessing and Sterilization of Reusable Medical Devices. 2011.