Regional Anaesthesia Block placement contamination risk
Ultrasound‐guided Regional Anaesthesia (RA)
Ultrasound‐guided Regional Anaesthesia (RA) has become a cornerstone for block placement. With quick turnaround times:
- Performing 10 to 30 blocks per day,
- Catheter placements,
- Not practical to move probes to and from Central Sterilisation Departments for disinfection.
Common practice (conventional technique*) is low‐level disinfection with a sterile probe cover. If the probe cover is compromised, high‐level disinfection is necessary. 1
However, this integrity is subjective rather than factually proven.
Most clinicians performing these procedures know that perforation of the cover does occur, exposing the patient procedure site to cross-infection risk. 2
*Conventional technique – Interventional percutaneous procedure transducers.
Prevention is Better than Cure 100%
Research study (HLD & no probe cover), highlighted key advantages over the conventional techniques. 2
- The HLD process is ultrafast. Researches stated that placing a probe in a sterile cover with gel takes longer than the 90 second UV-C HLD cycle.
- The researchers found without a cover, “enables enhancement of ultrasound contrast, which can facilitate better visualisation of anatomic landmarks and improve the feasibility of ultrasound-guided regional anaesthesia.”
- Automated traceability.
- Probe can be immediately disinfected before a new procedure.
In similar studies in Transoesophageal Echocardiography (TOE) studies question whether the cover sheath offers any advantage in reducing infection risk. 3-4
- As cleaning and disinfection are still needed to prevent probe contamination, it is not clear whether the cover sheath offers any advantage over standard measures for infection prevention. 4-6
- Sheaths are subject to perforation which may be undetectable to the naked eye.
- Perforation rates are as high as 4.4%.
Studies concluded, probes should undergo high level disinfection before each procedure and guidelines recommend sheath covers to be used. 6-8
Probe Covers NOT 100% Protection Proof
- AIUM – Official Statement – Guidelines for Cleaning and Preparing External- and Internal-Use Ultrasound Transducers Between Patients, Safe Handling, and Use of Ultrasound Coupling Gel Approved 5/16/2017; Revised 3/25/2018; Revised 11/3/18 https://www.aium.org/accreditation/Guidelines_Cleaning_Preparing.pdf
- Bloc S1, Mercadal L, Garnier T, Komly B, Leclerc P, Morel B, Ecoffey C, Dhonneur G. (2011) Evaluation of a new disinfection method for ultrasound probes used for regional anesthesia: ultraviolet C light. J Ultrasound Med. 2011 Jun;30(6):785-8. https://www.ncbi.nlm.nih.gov/pubmed/21632992
- Geneviève Côté, André Denault. Review Article: Transesophageal echocardiography-related complications [Complications associées à l’échocardiographie transoesophagienne] Can J Anesth 2008 / 55: 9 / pp 622–647.
- Fritz S, Hust MH, Ochs C, Gratwohl I, Staiger M, Braun B. Use of a latex cover sheath for transesophageal echocardiography (TEE) instead of regular disinfection of the echoscope? Clin Cardiol 1993; 16: 737–40.
- Khandheria BK. The transesophageal echocardiographic examination: is it safe? Echocardiography 1994; 11: 55–63.
- Richard Steeds. et al. Guidelines for transoesophageal echocardiographic probe cleaning and disinfection from the British Society of Echocardiography Article in European Heart Journal – Cardiovascular Imaging October 2011.
- Cote G, Denault A. Transoesophageal echocardiography-related complications. Can J Anesth 2008; 55(9): 622-647.
- Fritz S, Hust MH, Ochs C, et al. Use of latex cover sheath for transoesophageal echocardiography (TEE) instead of regular disinfection of echoscope? ClinCardiol 1993;16:737-40.