Cognitive aids: time for a change?

Cognitive aids are documents, visual prompts or decision guides that, unlike guidelines or protocols, are used when tasks are being performed. In anaesthetics and emergency care, checklists and algorithms are the most common formats used. Checklists contain actions or tasks that cannot be readily recalled due to their sheer number, or where the correct sequence of tasks is important. Their use does not imply cognitive impairment of the users, but they are used to improve individual and team performance. They are often used in high-pressure occupations and environments where a complete set of checks are vital, such as a take-off drill in aviation 1 or in pre-operative checks for surgery. All tasks performed by humans and healthcare systems are prone to error 2. When patient safety depends upon performing the correct actions in a complex system, any tool that reduces errors is potentially valuable. It has been argued that cognitive aids have this capability 3, and in medicine there is compelling evidence that they work, particularly in the avoidance of minor errors that have the potential to increase morbidity and mortality. The introduction of the World Health Organization (WHO) surgical safety checklist in 2009 was associated with a significant reduction in morbidity and mortality associated with surgery 4. This would prevent at least half a million deaths if the results of the study were extrapolated to a global scale. It is clear that a simple checklist, if used properly, is capable of improving patient care and delivering major organisational benefit. There are many other examples of the benefits of checklists in high-risk situations. In anaesthesia, checklists have been developed to reduce the incidence of harm that may result from forgetfulness, carelessness or distraction such as wrong-side nerve blocks 5, retained throat packs 6 and residual anaesthetic drugs retained in intravenous cannulae 7. Typically, they are a developed locally as part of an action plan to address critical incidents that have occurred, and take the form of posters designed to aid recollection of the main message. For example, in a checklist designed to help prevent wrong injections 8, an acronym (REFLECT) was used to aid recollection. Design is important. The Association of Anaesthetists of Great Britain and Ireland (AAGBI)'s guidelines Checking Anaesthetic Equipment 2012 9, 10 is a commonly used cognitive aid designed to reduce the incidence of errors associated with the use of anaesthetic equipment, and it demonstrates many key features of a good cognitive aid. The listed items are the result of consensus decisions by experts and summarise best evidence at the time of publication. In order to remain relevant, such guidelines are updated regularly in response to critical incident reports 11 and where the introduction of new equipment necessitates modification of the checklist. Checking an anaesthetic machine by using the AAGBI checklist provides evidence that due care and diligence has been applied in at least that part of an anaesthetist's work. Anaesthetists are supervisors of complex systems, and they continuously interact with equipment, patient physiology, and other theatre users. Although there is much that can go wrong with these interactions, many problems can be anticipated. An anaesthetist becomes more experienced by learning complex patterns that are continuously reinforced during training and practice, but the vast majority of learning takes place during management of routine cases rather than emergencies. Inevitably, skills are less developed to manage emergency situations, even if there has been specific training for emergency management. Emergencies may be novel and difficult to predict, and tend to result from a chain of events rather than a single human or equipment failure 12. In the management of anaesthetic emergency situations, there tends to be an over-reliance on experience gained during routine practice to solve problems posed by emergencies, and a reluctance to discard prior assumptions in order to find a solution. In other words, there is always potential for disaster in emergency management because of an unwillingness or inability to revert to more systematic thinking. This is termed fixation error 13 and it has been well described in anaesthesia 14, 15. An example of this type of error in the literature is that of a case of ventilation failure during anaesthetic management of a paediatric patient. This was misdiagnosed as bronchospasm, whereas in fact equipment failure (tube blockage) was the cause 16. Another factor to be considered during management of emergencies is stress. Emergencies are by their very nature stressful, resulting in an increase in cortisol and other stress hormones that are associated with a change in cognition and behaviour. In such circumstances, accurate recall of information may be lost, resulting in missed treatment steps or mistakes in sequential procedures 17-19. Again, even when appropriate training in emergency management has been received, application of knowledge under stressful circumstances may be challenging, inconsistent and error-prone. Some emergency procedures are more complex than others. A sequence of tasks may change, depending on management choices made or the patient's response to treatment that only becomes clear as the task list is processed. Cognitive aids that encapsulate these decision-driven processes are often referred to as decision trees or algorithms, such as those used in Advanced Life Support (ALS) training 20. In situations such as this, these aids may be viewed as ‘cognitive crutches’ to provide visual and textual prompts during lapses of memory or, on another level, as tools that help individuals and teams cope with a rapidly changing, complex and stressful environment 3. However, algorithms may be overly complex and lead to errors of translation 21. In most anaesthetic emergencies, checklists are used. Most of the data on the usefulness of cognitive aids in emergencies have been derived from simulated crises, and indeed this may be the best method of assessment 22-24. It is known from simulated practice that there is considerable deviation from standard management of cardiac arrest in operating theatres 25, and that cognitive aids have been shown to improve adherence to stand-ard treatment and promote more effective management in similar circumstances, such as during the emergency management of malignant hyperthermia 22, 23 and local anaesthetic toxicity 26. They may also help by reducing dependency on factual recall during stress, and reduce errors by constraining actions to a pre-determined sequence of evidence-based interventions. In some cases, modern technology such as mobile phones may also play a part by making the cognitive aid immediately accessible whatever the location 27. Marshall has recently reviewed the use of cognitive aids during anaesthetic emergencies 21. He lists the properties of an ideal cognitive aid thus: (i) content must be derived from ‘best practice’ guidelines or protocols; (ii) the design should be appropriate for use in the context of the emergency situation; (ii) the cognitive aid should be familiar, in a format that has been used in practice and training; (iv) it should also assist other team members to perform their tasks in a coordinated manner. The first two properties seem self-evident; the third property makes the point that the aid should link to appropriate training, and the fourth property is important in teamworking. Marshall also makes the point that poorly designed cognitive aids have the potential for harm, whereas well-considered cognitive aids are capable of promoting and standardising best practice. The amount of visible information should be proportionate to the task to be carried out, and should not act as a distraction or impediment due to poor design. The implication is that their use should be validated and agreed before use. In another review, Nanji and Cooper have suggested that the use of cognitive aids should be considered for all rare emergency situations in anaesthesia 22, stating that they promote economy of action and speed of management. There is some evidence to support this view 22, 25, 28, but some studies have not reported improvement 29, 30 and poorly designed cognitive aids may even act as a distractor 21. The case for the widespread use of cognitive aids in emergency management currently appears weak, despite enthusiasm from some researchers. This issue of Anaesthesia includes an article by Marshall and Mehra that explores the effect of cognitive aids on team behaviours 31. These authors simulated a cannot-intubate cannot-ventilate scenario and studied the team interactions with and without a cognitive aid. The introduction of the cognitive aid significantly improved the non-technical skills of the anaesthetist in a simulated emergency. Successful management of anaesthetic emergencies relies not only on the individual skills of the anaesthetist, but also on the way in which the individual skills of the team are used. Non-technical skills such as standardised communication are known to be important in teamworking in emergencies 32. Cognitive aids allow access to the same management plan for all members of the team, aiding communication and facilitating the sharing of knowledge 33. In Marshall and Mehra's study, the Anaesthetic Non-Technical Skill (ANTS) scoring system 34, a validated, commonly used method of assessment, was used to assess team behaviours, and the significant practical problems inherent in this type of study seem to have been well managed. These results are encouraging, and add to the body of evidence that supports the use of cognitive aids in emergency management. It is already known that they promote retention of skills following resuscitation training 35, and they are already a component of this type of training. Perhaps the main focus of resuscitation training and assessment should now move from rote learning of facts by individuals to team development, using cognitive aids as a focus and guide. This method could also be used for operating theatre emergencies. Checklists are already being used extensively, but theatre team training for common emergencies using cognitive aids would seem a logical next step. This may also reduce the emphasis on expensive individual training, where skills and knowledge are known to deteriorate rapidly following training 36, perpetuating a never-ending requirement for retraining and recertification. Changing culture to adopt and embrace cognitive aids may take some time. However, it seems a more logical approach than perpetuating intermittent emergency training that can only prepare the individual for standardised emergencies. We know that the actual workplace is far more complex, and that many emergencies are too rare to demonstrate convincingly an improvement in management in the workplace as a result of training. Planned links between the knowledge and skills gained during training and the workplace environment (such as cognitive aids) may help to address this problem of translation. Although the case for the use of cognitive aids in anaesthetic emergencies is still being developed, an increase in their use seems inevitable with the proliferation of national and local guidelines and the inexorable demand for accountability and transparency of clinical decisions. Most of the evidence for cognitive aids inevitably comes from a small number of studies that use simulated emergencies as a proxy for actual emergencies. Even with the adoption of nationally developed cognitive aids and widespread adoption, efficacy will be difficult to prove and there may never be first-level evidence, for a variety of reasons 37. On the other hand, much of the current evidence base for emergency management in anaesthesia is built on consensus of experts rather than evidence of efficacy. The evidence for the adoption of cognitive aids using simulated emergencies seems as strong as the evidence for what we would currently regard as best practice. The AAGBI has already developed a comprehensive list of guidelines to guide practice (see www.aagbi.org/publications/publications-guidelines). Perhaps the next step should be the development of cognitive aids for the management of anaesthetic room emergencies using national expert consensus and pooled resources. Aids developed in such a way, fully considering human factors in design, must surely be better than locally developed aids that, due to lack of resources, may not be ideal or even fit for purpose. However, to meet local needs the cognitive aid may need to be adapted for local circumstances without losing critical design elements. Experience with the AAGBI's Checking Anaesthetic Equipment has shown that national development and local adaption is possible and desirable. Despite local differences in equipment, it would seem unthinkable to return to a position of locally developed cognitive aids for checking anaesthetic equipment. Investment in cognitive aids seems to be an effective measure to help the clinician to apply the principles of best practice when most needed, and has the potential to reduce morbidity and mortality from anaesthetic emergencies. To maximise benefit, cognitive aids need to be developed at a national level. No external funding or competing interests declared.