Infection Control

This page covers general considerations and specific directions; we draw heavily from the work of Ma et al and recommendations for machine disinfection in the context of COVID-19.(1)

GUIDING PRINCIPLES

  • For patients on infection control precautions we recommend POCUS be performed ONLY in situations where it will assist in diagnosis and management
  • Patients on precautions should not undergo “educational” scans where there is no indication for sonography
  • Clinical risk and testing status for transmissible pathogens should be assessed prior to every study
  • In scenarios where risk of exposure is high, scanning should be delegated to the most experienced operator to minimize exposure time to the patient environment
  • Strict infection control measures must be followed before and after every patient encounter

INFECTION CONTROL
The below practices should be used with all patients on contact, droplet, or airborne precautions.

  • Remove all extra equipment prior to entering the patient room (e.g. towels, gel, )
  • Configure appropriate transducer settings, patient details, and login information prior to entering the patient room
  • Consider use of sterile probe sheaths
  • Use only single-use sterile gel packs
  • Minimize scanning time
  • After completing the study, remain donned in PPE without exiting the patient room, change gloves, and sanitize the machine with viru/bactericidal wipes: to truly disinfect the machine components there must be a minimum of 1-3 min minute of ‘wet contact’ time, do not immediately dry

MACHINE CLEANING

Ultrasound carts/handheld devices are classified non-critical by Spaulding classification as they are in contact with intact skin and therefore require only low/intermediate disinfection with disinfecting wipes. Machines should be cleaned after EVERY patient encounter regardless of infection control precautions.

If there is need to use a probe on non-intact skin or mucus membranes a sterile cover should always be used.

In terms of cleaning sequence the overarching principle is to begin with areas of lowest soilage to highest to avoid contamination during the cleaning process as shown in the figure below.

Use only approved cleaning materials for machines/by unit policy; on our unit this includes Oxivir Wipes, Cavi Wipes, Bleach Wipes. Oxivir requires 1 minute of wet contact time, Cavi and bleach wipes require 3 minutes.

Always turn off the machine before disinfecting.

Remove gel/blood/debris with a cloth or blue pad before using disinfecting wipes. NEVER clean probes/machine components by immersion.

  1. Begin with all parts of the machine which have contact with the environment except the wheels (*trays/handles/tower/cord etc.); change wipes at this point
  2. Next wipe down the screen +/- lid of the display
  3. Next move to the controls/keyboard (if present)
  4. This is followed by transducer cords, clean from the connection to the console proximally to the transducer distally
  5. The transducer itself is last, clean the handle first; the head (point of contact with the patient) is cleaned last

Reference

  1. Ma IW, Somayaji R, Rennert-May E, Minardi J, Walsh MH, Wiskar K, Smyth LM, Burgoyne S, Chan B, Haroon BA, Desy J. Canadian Internal Medicine Ultrasound (CIMUS) recommendations regarding internal medicine point-of-care ultrasound (POCUS) use during Coronavirus (COVID-19) pandemic. Canadian Journal of General Internal Medicine. 2020 Apr 1;15(2):8-11.