Anaesthetists reminded to 'stop before you block'

New guidance on anaesthetic nerve blocks aims to avoid errors.

Despite several initiatives aimed at improving the safety of anaesthetic blocks - where local anaesthetic is used to numb the nerves on a part of the body - errors do occasionally occur. In an MDU study of anaesthetic claims, needle misplacement, including during nerve block procedures, occurred in 17% of cases and was the third most common cause of claims.

The Safe Anaesthesia Liaison Group (SALG) has recently updated the 'stop before you block' (SBYB) guidance. The revised and updated guidance follows a Healthcare Safety Investigations branch report into wrong side regional anaesthetic block in 2018.

On its new guidance webpage, SALG reports that despite the introduction and widespread use of the SBYB process, wrong side blocks remain difficult to eradicate, affecting approximately one in 6,000 regional anaesthetics.

In producing the revised guidance, SALG emphasises that the second 'stop' stage of the process is meant to occur immediately before the needle is inserted. The new process is designed as a standard operating policy that it is hoped will be adopted nationally. The process is broken down into three steps.

Step 1: preparation

The guidance explains that this stage includes the blocker (usually the anaesthetist) preparing the local anaesthetic solution and placing "the labelled syringe with a suitable nerve block needle in a dedicated tray/container, which is handed over to the assistant, out of the blocker's immediate reach".

Step 2: stop

This is described in the guidance as, "a two-person step that happens only after preparation is complete and thus immediately before needle insertion. When ready, the blocker formally announces that they have completed all preparation and is ready to block using a consistent form of words: 'I've completed my prep; let's Stop before You Block.' The assistant similarly should reply: 'OK, let's Stop before You Block.'

"The blocker and blocker's assistant together should then check the block side by viewing the surgical site mark and verbally confirming the correct side; the assistant reconciles this with the consent form. If the patient is awake and unsedated they may also confirm the side is correct."

Step 3: block

The guidance explains: "Only when the correct side is confirmed does the assistant hand the tray/container [containing the anaesthetic] to the blocker. The blocker immediately performs the block. Any delay between handing back the tray and/or performing the block should require the blocker and assistant to re-start the SBYB process at Step 1."

Along with improving patient safety by avoiding wrong site errors, another benefit of rolling out the new SBYB guidance as a standard operating policy is that future patient safety incidents involving wrong side anaesthetic blocks should be easier to investigate. This is because the procedure is likely to be more consistently followed.

This page was correct at publication on 06/01/2022. Any guidance is intended as general guidance for members only. If you are a member and need specific advice relating to your own circumstances, please contact one of our advisers.

Mike Devlin, Interim Medical Editor

by Dr Michael Devlin LLM, MBA, FRCP, FRCGP, FFFLM MDU head of professional standards and liaison

Michael was an MDU medico-legal adviser for 15 years, latterly as head of medico-legal services, before taking up the new role of head of professional standards and liaison. He sat on the FFLM's academic committee and was previously treasurer, and an examiner for the MFFLM. He has published widely on medico-legal matters, and has significant experience in teaching and assessing knowledge in medico-legal subjects.