Implementing human factors in anaesthesia: guidance for clinicians, departments and hospitals: Guidelines from the Difficult Airway Society and the Association of Anaesthetists: Guidelines from the Difficult Airway Society and the Association of Anaesthetists.

Human factors is an evidence-based scientific discipline used in safety critical industries to improve safety and worker well-being. The implementation of human factors strategies in anaesthesia has the potential to reduce the reliance on exceptional personal and team performance to provide safe and high-quality patient care. To encourage the adoption of human factors science in anaesthesia, the Difficult Airway Society and the Association of Anaesthetists established a Working Party, including anaesthetists and operating theatre team members with human factors expertise and/or interest, plus a human factors scientist, an industrial psychologist and an experimental psychologist/implementation scientist. A three-stage Delphi process was used to formulate a set of 12 recommendations: these are described using a 'hierarchy of controls' model and classified into design, barriers, mitigations and education and training strategies. Although most anaesthetic knowledge of human factors concerns non-technical skills, such as teamwork and communication, human factors is a broad-based scientific discipline with many other additional aspects that are just as important. Indeed, the human factors strategies most likely to have the greatest impact are those related to the design of safe working environments, equipment and systems. While our recommendations are primarily provided for anaesthetists and the teams they work with, there are likely to be lessons for others working in healthcare beyond the speciality of anaesthesia.

Human factors in anaesthesia: a narrative review.

Healthcare relies on high levels of human performance, as described by the 'human as the hero' concept. However, human performance varies and is recognised to fall in high-pressure situations, meaning that it is not a reliable method of ensuring safety. Other safety-critical industries embed human factors principles into all aspects of their organisations to improve safety and reduce reliance on exceptional human performance; there is potential to do the same in anaesthesia. Human factors is a broad-based scientific discipline which aims to make it as easy as possible for workers to do things correctly. The human factors strategies most likely to be effective are those which 'design out' the chance of an error or adverse event occurring. When errors or adverse events do happen, barriers are in place to trap them and reduce the risk of progression to patient and/or worker harm. If errors or adverse events are not trapped by these barriers, mitigations are in place to minimise the consequences. Non-technical skills form an important part of human factors barriers and mitigation strategies and include: situation awareness; decision-making; task management; and team working. Human factors principles are not a substitute for proper investment and appropriate staffing levels. Although applying human factors science has the potential to save money in the long term, its proper implementation may require investment before reward can be reaped. This narrative review describes what is known about human factors in anaesthesia to date.

Impact of change in head and neck position on ultrasound localisation of the cricothyroid membrane: an observational study.

The ideal position for performing surgical cricothyroidotomy is with full neck extension. Some authors have recommended marking the cricothyroid membrane before general anaesthesia, typically with the patient's head and neck in a neutral position. The primary aim of this observational study was to determine whether skin marks made over the centre of the cricothyroid membrane with the head and neck in the neutral position moved outside the boundaries of the membrane when the neck was subsequently extended. The secondary aim was to assess changes in the height of the cricothyroid membrane between the neutral and extended positions. Twenty-two volunteers completed the study. With the head and neck in the neutral position, the distance between the upper and lower borders ('height') of the cricothyroid membrane was measured by a radiologist using ultrasound. The skin was marked over the mid-point of the membrane. The subject then maximally extended the neck, and the measurements and marking were repeated. The skin marking over the centre point of the cricothyroid membrane moved by median (IQR [range]) 5 (4-6 [0-10]) mm when the head and neck were moved from a neutral to a fully extended position. The initial skin mark moved to lie outside the boundary of the cricothyroid membrane in 12 of 22 subjects after extending the neck. The height of the cricothyroid membrane increased by 30% with the neck extended. We recommend that marking the skin in preparation for cricothyroidotomy should be performed with the neck extended, not with the head and neck in the neutral position as previously suggested.

A national survey of the impact of NAP4 on airway management practice in United Kingdom hospitals: closing the safety gap in anaesthesia, intensive care and the emergency department.

BACKGROUND: The 4th National Audit Project of the Royal College of Anaesthetists' and Difficult Airway Society (NAP4) made recommendations to improve reliability and safety of airway management in hospitals. This survey examines its impact. METHODS: A survey was sent to all UK National Health Service hospitals to examine changes in practice in response to NAP4. We performed a 'gap analysis' to determine whether NAP4 had reduced the 'safety gap' between actual and ideal practice. RESULTS: The response rate was 62% (192 of 307 hospitals), and 78% answered all questions. Most (97%) respondents reported changes in practice in response to NAP4 but these differed by specialty: 95% in anaesthesia; 80% in intensive care (ICU) and 59% in the emergency department (ED). Approximately 25% reported changes in organizational aspects of airway and human factors teaching. Practice changes led to a median closure of the 'safety gap' in anaesthesia of 39% (IQR 14-66%, range 11-83%), 59% in ICU (IQR 54-73%, range 31-81%) and 48% in ED (IQR 39-53%, range 35-53%). CONCLUSIONS: Publication of NAP4 was followed by changes in practice in the majority of responding departments within two yr. Improvements included improved provision of difficult airway equipment and more widespread routine use of capnography. The biggest change occurred in ICU; the impact on training nursing and junior staff was modest and here, significant safety gaps remain.

Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults.

These guidelines provide a strategy to manage unanticipated difficulty with tracheal intubation. They are founded on published evidence. Where evidence is lacking, they have been directed by feedback from members of the Difficult Airway Society and based on expert opinion. These guidelines have been informed by advances in the understanding of crisis management; they emphasize the recognition and declaration of difficulty during airway management. A simplified, single algorithm now covers unanticipated difficulties in both routine intubation and rapid sequence induction. Planning for failed intubation should form part of the pre-induction briefing, particularly for urgent surgery. Emphasis is placed on assessment, preparation, positioning, preoxygenation, maintenance of oxygenation, and minimizing trauma from airway interventions. It is recommended that the number of airway interventions are limited, and blind techniques using a bougie or through supraglottic airway devices have been superseded by video- or fibre-optically guided intubation. If tracheal intubation fails, supraglottic airway devices are recommended to provide a route for oxygenation while reviewing how to proceed. Second-generation devices have advantages and are recommended. When both tracheal intubation and supraglottic airway device insertion have failed, waking the patient is the default option. If at this stage, face-mask oxygenation is impossible in the presence of muscle relaxation, cricothyroidotomy should follow immediately. Scalpel cricothyroidotomy is recommended as the preferred rescue technique and should be practised by all anaesthetists. The plans outlined are designed to be simple and easy to follow. They should be regularly rehearsed and made familiar to the whole theatre team.

Human factors in the development of complications of airway management: preliminary evaluation of an interview tool.

The 4th National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society (NAP4) analysed reports of serious events arising from airway management during anaesthesia, intensive care and the emergency department. We conducted supplementary telephone interviews with 12 anaesthetists who had reported to NAP4, aiming to identify causal factors using a method based on the Human Factors Investigation Tool (HFIT). We identified contributing human factors in all cases (median [range] 4.5 [1-10] per case). The most frequent related to: situation awareness (failures to anticipate, wrong decision) (nine cases); job factors (e.g. task difficulty; staffing, time pressure) (eight cases); and person factors (e.g. tiredness, hunger, stress) (six cases). Protective factors, such as teamwork and communication, were also revealed. The post-report HFIT interview method identified relevant human factors and this approach merits further testing as part of the investigation of anaesthetic incidents.

Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: anaesthesia.

BACKGROUND: This project was devised to estimate the incidence of major complications of airway management during anaesthesia in the UK and to study these events. METHODS: Reports of major airway management complications during anaesthesia (death, brain damage, emergency surgical airway, unanticipated intensive care unit admission) were collected from all National Health Service hospitals for 1 yr. An expert panel assessed inclusion criteria, outcome, and airway management. A matched concurrent census estimated a denominator of 2.9 million general anaesthetics annually. RESULTS: Of 184 reports meeting inclusion criteria, 133 related to general anaesthesia: 46 events per million general anaesthetics [95% confidence interval (CI) 38-54] or one per 22,000 (95% CI 1 per 26-18,000). Anaesthesia events led to 16 deaths and three episodes of persistent brain damage: a mortality rate of 5.6 per million general anaesthetics (95% CI 2.8-8.3): one per 180,000 (95% CI 1 per 352-120,000). These estimates assume that all such cases were captured. Rates of death and brain damage for different airway devices (facemask, supraglottic airway, tracheal tube) varied little. Airway management was considered good in 19% of assessable anaesthesia cases. Elements of care were judged poor in three-quarters: in only three deaths was airway management considered exclusively good. CONCLUSIONS: Although these data suggest the incidence of death and brain damage from airway management during general anaesthesia is low, statistical analysis of the distribution of reports suggests as few as 25% of relevant incidents may have been reported. It therefore provides an indication of the lower limit for incidence of such complications. The review of airway management indicates that in a majority of cases, there is 'room for improvement'.