Utilisation of ‘verbalisation’ to reduce the complications of tracheal intubation

We read with interest the study in which Jelacic et al. 1 demonstrate the benefit of a pre-induction aviation-style computerised checklist in reducing non-routine induction events and missing critical pre-induction actions. With the increasing recognition of the advantages of utilising checklists to act as prompts in order to avoid missing critical steps, the Difficult Airway Society (DAS), in collaboration with the Intensive Care Society, the Royal College of Anaesthetists and the Faculty of Intensive Care Medicine have recently launched a tracheal intubation checklist for the preparation of tracheal intubation in the critically ill adult patient. Checklist-based approaches to maximise patient safety at induction are to be commended and should be considered for all patients requiring tracheal intubation. Although rare, the National Audit Project of the Royal College of Anaesthetists on major complications of airway management (NAP4) and accidental awareness during general anaesthesia (NAP5) demonstrate that catastrophic complications occur during and after tracheal intubation. These events include: failure to perform timely front-of-neck access in the occurrence of a ‘can't intubate can't oxygenate’ (CICO) event; failure to oxygenate caused by unrecognised oesophageal intubation; accidental endobronchial intubation; and accidental awareness during general anaesthesia (AAGA) caused by a failure to turn on the vaporiser following successful intubation. In many reported cases, better planning, communication and situational awareness could have mitigated or prevented patient harm, lending further credence to the benefit of utilising checklists and prompts that ensure all necessary steps are reliably performed. As well as written checklists and aviation-style checklists, verbalisation of important steps (also known as risk-triggered commentary) has been demonstrated to reduce human error when complex tasks are performed 2. The act of verbalisation facilitates the cognitive control processes that are necessary for effective retrieval and activation of working memory to be reinforced. In addition, if the operator is part of a team it allows the coworkers to know that the task has been satisfactorily completed. Consequently, it is used extensively by the airline and rail industries to reduce human error 2, 3 and is especially recommended for single pilots 3. Therefore, we propose that all of the aforementioned pre-intubation checklists could, and should, be improved by the addition of a further five standardised statements to be verbalised during and immediately after tracheal intubation in order to ensure safe placement of the tracheal tube and to reduce the occurrence of induction-related AAGA. These statements and their rationale are summarised in Table 1. We congratulate Jelacic et al. and DAS for their efforts to enhance safety and pre-induction preparation through the use of checklists. Moreover, in line with other safety-conscious industries, we suggest the anaesthetic community considers adopting the practice of ‘verbalisation’, especially during the period of tracheal intubation.