External ultrasound probes are those which only come into contact with intact skin during a procedure. These probes are considered non-critical devices and require cleaning and low‐level disinfection after each use.
Although external probes are intended for use on intact skin, they can still contribute to the transmission of infectious agents either by contaminated hands of a health-care professional, contamination on the probe itself, or, even from the gel/gel bottle used during procedures.
While reusable multi-use non-sterile gel bottles may be used for low-risk general examinations on intact skin, they are not considered best practice. These reusable multi-use non-sterile gel bottles can be easily contaminated and have been involved in the transmission of infectious agents associated with outbreaks of infection.
The following practices must be adhered to when using reusable multi-use non-sterile gel containers/bottles:
- Dispense gel from the original gel manufacturer’s container and use a clean dispensing device
- Never “top up” gel bottles that are partially full
- Refill the bottle only after it has been emptied, cleaned (using a medical grade detergent, rinsed and dried) and then disinfected with a medical grade low-level disinfectant
- Label a newly opened or newly refilled gel bottle with the date
- Discard any unused gel left in bottle after 28 days
- Unused gel is discarded if at any time the cleanliness of the bottle or contents is questioned or compromised, or if the bottle is not marked with the fill date
- After each patient use, wipe the outside of the gel bottle with a medical grade low-level disinfectant and ensure lid is closed
- Never heat gel bottles for use
If an external ultrasound probe is used for a procedure that involves a sterile field, such as for needle guidance, both the gel and the probe cover must be sterile.
Always follow the manufacturer’s instructions for the ultrasound probe. Other basic infection prevention and control measures, including hand hygiene and environmental cleaning and disinfection, are also essential to prevent the transmission of pathogens in medical ultrasound.