Reproducible, validated probe decontamination

Transoesophageal Echocardiography (TOE), being a semi invasive procedure, means that the potential for the transmission of infection between patients is a risk. Examples of agents that can potentially be transferred, from patient to patient, through inadequate decontamination of TOE probes, include: bacteria (such as Helicobacter pylori, Pseudomonas aeruginosa, Salmonella species and mycobacterium species); viruses (such as hepatitis B and C, and HIV); and prions (including vCJD). There is also a risk of contamination from the decontamination procedure, including exposure to Pseudomonas aeruginosa, Legionella pneumophila and mycobacteria. 

In 2011, guidelines were published in The European Journal of Echocardiography – Guidelines for Transoesophageal echocardiographic probe cleaning and disinfection from the British Society of Echocardiography – offering advice on ‘best practice’ for TOE probe decontamination.1 Although the authors found minimal evidence that there is a risk of cross-infection, they stated that the absence of such evidence should not be considered as evidence of the absence of risk. They went on to state that estimating the infection risk is difficult because there are no well performed comprehensive studies relating to infection control TOE practice and the onset of infections relating to procedures may be delayed until after the patient is discharged from hospital, making diagnosis and reporting unlikely. 

However, in 2012, an inquest into the death of a 68 year old patient subsequently identified that a TOE probe used during heart surgery was inadequately decontaminated and caused a cross infection of Hepatitis B. The Coroner found that it was more than likely that Hepatitis B was transferred from another patient because of failures in decontaminating a TOE probe.