Are checklists a valuable tool to prevent wrong-side blocks?

We read with interest the audit published by McLellan et al ¹ assessing the introduction of a mandatory pre-block safety checklist. Wrong-side blocks are uncommon, may cause morbidity and should be regarded as ‘never’ events ² . Following one such event, the authors undertook a quality improvement project aiming to achieve 80% compliance with a pre-existing institution-specific checklist. Checklist compliance increased from 31% to 91% post-intervention. Importantly, no detrimental impact to other quality measures was identified in the post-intervention audit.

We have several concerns about the objective and effectiveness of the intervention. Taking into consideration the block room setup described by the authors and the rarity of wrong-side blocks (the authors quote 1/2800–1/8100), aiming for less than 100% checklist compliance is questionable. For an intervention that achieved departmental consensus and was considered mandatory, both the aim of 80% and the result of 91% compliance appear inadequate. Increased compliance with the checklist also made no statistically significant difference to immediate complications (4% versus 3%), raising the question of whether a wrong-side block would indeed be prevented.

The focus on completing a multi-item pre-block checklist may inadvertently de-emphasise the critical importance of the block ‘time-out’. When the Nottingham University Hospital anaesthetic department originally introduced ‘Stop Before You Block’, they emphasised the ‘stop moment’ that occurs just prior to needle insertion as the most important element ³ . The Australian and New Zealand College of Anaesthetists guideline similarly recommends a block time-out before regional procedures, rather than a checklist ⁴ . The original article also highlights the nine-point pre-block checklist recommended by the American Society of Regional Anesthesia and Pain Medicine ⁵ . However that paper too underscores the crucial importance of the block time-out, acknowledging that there is insufficient evidence to affirm that checklists of themselves reduce wrong-side blocks.

Given that a wrong-side block triggered the quality improvement process, the rationale for persisting with a broad pre-existing checklist was not clearly explained. The checklist contains 17 items, many of which are already incorporated in the widely adopted Australian version of the World Health Organization sign-in checklist ⁶ . Checklists themselves are unlikely to improve safety if they are not coupled with behaviour and culture change, and at worst may foster complacency through inattentive box-ticking ⁷ . Their overuse during the perioperative period can impede clinicians through ‘checklist fatigue’ ⁸ . The early success of the authors’ model and its collateral benefits (trainee involvement, ultrasound recording) may reflect the care and effort afforded to attitude change, rather than the mandatory completion of a checklist.