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Disinfection of ultrasound and pachymeter probes

Wednesday March 14, 2018
Subject: Disinfection of ultrasound and pachymeter probes

Dear Karin and Joe,

On behalf of the membership of the Eye Physicians and Surgeons Association of Alberta (EPSAA) and the Canadian Ophthalmological Society (COS), we are writing to you to express our concerns with the recommendations put forward in the Alberta Health Services (AHS) Medical Device Reprocessing (MDR) of Semi-Critical Devices used in Ophthalmology Briefing Document, dated February 26, 2018, with regard to higher level sterilization of ultrasound probes and ultrasonic pachymeter probes.

First of all, thank you to you and Karin for involving Dr. Mike Ashenhurst and myself in these discussions. We believe that consultation with Ophthalmology on this proposed change is key to keeping patients’ best interest in mind – and this includes ensuring diagnostic instruments remain available and are accurate, while minimizing the risk of harm. As we move forward it is important that we weigh the risk of harm carefully by critically examining the available evidence before making decisions that may impact the accuracy or availability of testing.

The Canadian Ophthalmological Society and the Eye Physicians and Surgeons of Alberta (EPSAA) are in the process of reviewing the evidence and preparing a position statement on this issue. At the present time there is no published evidence of disease transmission from pachymeter or ultrasound probes and approved methods of high level disinfection can cause degradation of probe performance which reduces the accuracy of testing. Our key concerns with the suggested disinfection procedure changes include:

  • There is no published evidence to suggest the spread of infection via pachymeter and ultrasound probes. Disinfection chemicals or the process of doing so (constantly removing the probe tips) could damage devices resulting in loss of diagnostic accuracy and premature need for replacement. In addition, studies with tonometer tips have demonstrated the potential for surface breakdown from repeated high level disinfection leading to microfissures which harbour organisms and chemicals making them more resistant to cleaning. As these probes have a similar construction a similar problem might be expected.
  • A process which leaves disinfection chemicals in the room or the possibility of chemical residue on the probe tips increases the potential for iatrogenic damage to the patient’s cornea.

We also feel that attention could be given to preventative measures:

  • If a patient comes in with a red eye that is deemed by a health care worker to be possible conjunctivitis, then a ‘Red eye protocol’ could be instituted. This would mean the patient sits on a chair which is cleaned afterwards (to prevent fomite transmission), and that the room that they are examined in along with various pieces of equipment that they come into contact with are cleaned appropriately Use of contact testing equipment would be limited to disposable devices in this situation.

As the medical and surgical leaders in eye health, and the end users of this technology, we feel it’s important for us to stay involved in this process. We would appreciate the opportunity to work collaboratively to help inform a thoughtful approach as to how to address this issue in a way that keeps our patients’ best interests in mind, but also balances the provider and institutional interests. Please let us know how we can participate in next steps on this. We will also follow up with you shortly to discuss how we can further assist.

With best regards,

Karim F. Damji, MD, FRCSC, MBA
Professor and Chair, Department of Ophthalmology and Visual Sciences, University of Alberta Clinical Section Head for Ophthalmology, Edmonton, Zone