Handling injectable medications in anaesthesia: Guidelines from the Association of Anaesthetists.

Peri-operative medication safety is complex. Avoidance of medication errors is both system- and practitioner-based, and many departments within the hospital contribute to safe and effective systems. For the individual anaesthetist, drawing up, labelling and then the correct administration of medications are key components in a patient's peri-operative journey. These guidelines aim to provide pragmatic safety steps for the practitioner and other individuals within the operative environment, as well as short- to long-term goals for development of a collaborative approach to reducing errors. The aim is that they will be used as a basis for instilling good practice.

New guidelines for research in airway device evaluation: time for an updated approach (ADEPT-2) to the Difficult Airway Society's 'ADEPT' strategy?

In this article we present the learning from a clinical study of airway device evaluation, conducted under the framework of the Difficult Airway Society (DAS, UK) 'ADEPT' (airway device evaluation project team) strategy. We recommend a change in emphasis from small scale randomised controlled trials conducted as research, to larger-scale observational, post-marketing evaluation audits as a way of obtaining more meaningful information.

Assessing a novel second generation laryngeal mask airway using the 'ADEPT' approach: results from the LMA® Protector™ observational study.

To address the problem of lack of clinical evidence for airway devices introduced to the market, the Difficult Airway Society (UK) developed an approach (termed ADEPT; Airway Device Evaluation Project Team) to standardise the model for device evaluation. Under this framework we assessed the LMA Protector, a second generation laryngeal mask airway. A total of 111 sequential adult patients were recruited and the LMA Protector inserted after induction of general anaesthesia. Effective insertion was confirmed by resistance to further distal movement, manual ventilation, and listening for gas leakage at the mouth. The breathing circuit was connected to the airway channel and airway patency confirmed with manual test ventilation at 20 cm H20 (water) pressure for 3 s. Data was collected in relation to the time for placement, intraoperative performance and postoperative performance of the airway device. Additionally, investigators rated the ease of insertion and adequacy of lung ventilation on a 5-point scale. The median (interquartile range [range]) time taken to insertion of the device was 31 (26-40[14-780]) s with the ability to ventilate after device insertion 100 (95% CI 96.7- 100)%. Secondary endpoints included one or more manoeuvres 60.3 (95% CI 50.6-69.5)% cases requiring to assist insertion; a median ease of insertion score of 4 (2-5[3-5]), and a median adequacy of ventilation score of 5 (5-5[4-5]). However, the first time insertion rate failure was 9.9% (95% CI 5.1-17.0%). There were no episodes of patient harm recorded, particularly desaturation. The LMA Protector appears suitable for clinical use, but an accompanying article discusses our reflections on the ADEPT approach to studying airway devices from a strategic perspective.

The effect of overlapping surgical scheduling on operating theatre productivity: a narrative review.

This article reviews the background to overlapping surgery, in which a single senior surgeon operates across two parallel operating theatres; anaesthesia is induced and surgery commenced by junior surgeons in the second operating theatre while the lead surgeon completes the operation in the first. We assess whether there is any theoretical basis to expect increased productivity in terms of number of operations completed. A review of observational studies found that while there is a perception of increased surgical output for one surgeon, there is no evidence of increased productivity compared with two surgeons working in parallel. There is potential for overlapping surgery to have some positive impact in situations where turnover times between cases are long, operations are short (<2 h) and where 'critical portions' of surgery constitute about half of the total operation time. However, any advantages must be balanced against safety, ethical and training concerns.

Oxygen sensing, anaesthesia and critical care: a narrative review.

In 2019, the scientists who discovered how cells sense and adapt to oxygen availability were awarded the Nobel Prize. This elegant sensing pathway is conserved throughout evolution, and it underpins the physiology and pathology that we, as clinicians in anaesthesia and critical care, encounter on a daily basis. The purpose of this review is to bring hypoxia-inducible factor, and the oxygen-sensing pathway as a whole, to the wider clinical community. We describe how this unifying mechanism was discovered, and how it orchestrates diverse changes such as erythropoiesis, ventilatory acclimatisation, pulmonary vascular remodelling and altered metabolism. We explore the lessons learnt from genetic disorders of oxygen sensing, and the wider implications in evolution of all animal species, including our own. Finally, we explain how this pathway is relevant to our clinical practice, and how it is being manipulated in new treatments for conditions such as cancer, anaemia and pulmonary hypertension.

Major complications of airway management: a prospective multicentre observational study.

We conducted an observational study of serious airway complications, using similar methods to the fourth UK National Audit Project (NAP4) over a period of 1 year across four hospitals in one region in the UK. We also conducted an activity survey over a week, using NAP4 methods to yield an estimate for relevant denominators to help interpret the primary data. There were 17 serious airway complications, defined as: failed airway management leading to cancellation of surgery (eight); airway management in recovery (five); unplanned intensive care admission (three); and unplanned emergency front of neck access (one). There were no reports of death or brain damage. This was an estimate of 0.028% (1 in 3600) complications using the denominator of 61,000 general anaesthetics per year in the region. Complications in patients with 'predicted easy' airways were rare (approximately 1 in 14,200), but 45 times more common in those with 'predicted difficult' airways (approximately 1 in 315). Airway management in both groups was similar (induction of anaesthesia followed by supraglottic airway or tracheal tube). Use of awake/sedation intubation, videolaryngoscopy and high-flow nasal oxygenation were uncommon even in the predicted difficult airway patients (in 2.7%, 32.4% and 9.5% of patients, respectively). We conclude that the incidence of serious airway complications is at least as high as it was during NAP4. Despite airway prediction being used, this is not informing subsequent management.

An analysis of the academic capacity of anaesthesia in the UK by publication trends and academic units.

Over a decade ago, bibliometric analysis predicted the disappearance of UK publishing in anaesthesia by 2020. We repeated this analysis to assess if this had turned out to be the case, searching PubMed for papers associated with UK consultant anaesthetists for 2017-2019 across 15 journals. Although the rate of decline has flattened using the same search filter, including a wider range of publication types shows that outputs still remain at half 1990s levels (381 papers for all 3 years combined), authored by 769 anaesthetists, 274 of whom are associated with an academic centre. There are now 11 identifiable academic units, and a further 15 places where anaesthetists have affiliations with academic centres as individuals. The majority of papers (71%) are in secondary analysis (observational, database and association studies, surveys and meta-analyses), rather than in primary research (clinical trials or laboratory studies). These data reflect the current academic capacity in terms of publications, academic units and staffing. We discuss how this information can be used to inform a new strategy for UK academic anaesthesia.

General anaesthesia in end-of-life care: extending the indications for anaesthesia beyond surgery.

In this article, we describe an extension of general anaesthesia - beyond facilitating surgery - to the relief of suffering during dying. Some refractory symptoms at the end of life (pain, delirium, distress, dyspnoea) might be managed by analgesia, but in high doses, adverse effects (e.g. respiratory depression) can hasten death. Sedation may be needed for agitation or distress and can be administered as continuous deep sedation (also referred to as terminal or palliative sedation) generally using benzodiazepines. However, for some patients these interventions are not enough, and others may express a clear desire to be completely unconscious as they die. We summarise the historical background of an established practice that we refer to as 'general anaesthesia in end-of-life care'. We discuss its contexts and some ethical and legal issues that it raises, arguing that these are largely similar issues to those already raised by continuous deep sedation. To be a valid option, general anaesthesia in end-of-life care will require a clear multidisciplinary framework and consensus practice guidelines. We see these as an impending development for which the specialty should prepare. General anaesthesia in end-of-life care raises an important debate about the possible role of anaesthesia in the relief of suffering beyond the context of surgical/diagnostic interventions.

How can Never Event data be used to reflect or improve hospital safety performance?

The absolute number of Never Events is used by UK regulators to help assess hospital safety performance, without account of hospital workload. We applied funnel plots, as an established means of taking workload into account, to published Never Event data for 151 acute Trusts in NHS England, matched to finished consultant episodes for 3 years, 2017-2020. Trusts with excess event rates should have the most Never Events if absolute number is a valid way to judge performance. The absolute number of Never Events was correlated with workload (r2 = 0.51, p < 0.001), but the five Trusts above the upper 95% confidence limit did not have the highest number of Never Events. However, a limitation to interpretation was that the data were skewed; 12 out of 151 Trusts lay below the lower 95% limit. This skew probably arises because funnel plots pool all Never Events and workload data; whereas, ideally, different Never Events should use as denominator only the relevant workload actions that could cause them. We conclude that the manner in which Never Event data are currently used by regulators, in part to judge or rate hospitals, is mathematically invalid. The focus should shift from identifying 'outlier' hospitals to reducing the overall national mean Never Event rate through shared learning and an integrated system-wide approach.

General anaesthetic and airway management practice for obstetric surgery in England: a prospective, multicentre observational study.

There are no current descriptions of general anaesthesia characteristics for obstetric surgery, despite recent changes to patient baseline characteristics and airway management guidelines. This analysis of data from the direct reporting of awareness in maternity patients' (DREAMY) study of accidental awareness during obstetric anaesthesia aimed to describe practice for obstetric general anaesthesia in England and compare with earlier surveys and best-practice recommendations. Consenting patients who received general anaesthesia for obstetric surgery in 72 hospitals from May 2017 to August 2018 were included. Baseline characteristics, airway management, anaesthetic techniques and major complications were collected. Descriptive analysis, binary logistic regression modelling and comparisons with earlier data were conducted. Data were collected from 3117 procedures, including 2554 (81.9%) caesarean deliveries. Thiopental was the induction drug in 1649 (52.9%) patients, compared with propofol in 1419 (45.5%). Suxamethonium was the neuromuscular blocking drug for tracheal intubation in 2631 (86.1%), compared with rocuronium in 367 (11.8%). Difficult tracheal intubation was reported in 1 in 19 (95%CI 1 in 16-22) and failed intubation in 1 in 312 (95%CI 1 in 169-667). Obese patients were over-represented compared with national baselines and associated with difficult, but not failed intubation. There was more evidence of change in practice for induction drugs (increased use of propofol) than neuromuscular blocking drugs (suxamethonium remains the most popular). There was evidence of improvement in practice, with increased monitoring and reversal of neuromuscular blockade (although this remains suboptimal). Despite a high risk of difficult intubation in this population, videolaryngoscopy was rarely used (1.9%).

Incidence of accidental awareness during general anaesthesia in obstetrics: a multicentre, prospective cohort study.

General anaesthesia for obstetric surgery has distinct characteristics that may contribute towards a higher risk of accidental awareness during general anaesthesia. The primary aim of this study was to investigate the incidence, experience and psychological implications of unintended conscious awareness during general anaesthesia in obstetric patients. From May 2017 to August 2018, 3115 consenting patients receiving general anaesthesia for obstetric surgery in 72 hospitals in England were recruited to the study. Patients received three repetitions of standardised questioning over 30 days, with responses indicating memories during general anaesthesia that were verified using interviews and record interrogation. A total of 12 patients had certain/probable or possible awareness, an incidence of 1 in 256 (95%CI 149-500) for all obstetric surgery. The incidence was 1 in 212 (95%CI 122-417) for caesarean section surgery. Distressing experiences were reported by seven (58.3%) patients, paralysis by five (41.7%) and paralysis with pain by two (16.7%). Accidental awareness occurred during induction and emergence in nine (75%) of the patients who reported awareness. Factors associated with accidental awareness during general anaesthesia were: high BMI (25-30 kg.m-2 ); low BMI (<18.5 kg.m-2 ); out-of-hours surgery; and use of ketamine or thiopental for induction. Standardised psychological impact scores at 30 days were significantly higher in awareness patients (median (IQR [range]) 15 (2.7-52.0 [2-56]) than in patients without awareness 3 (1-9 [0-64]), p = 0.010. Four patients had a provisional diagnosis of post-traumatic stress disorder. We conclude that direct postoperative questioning reveals high rates of accidental awareness during general anaesthesia for obstetric surgery, which has implications for anaesthetic practice, consent and follow-up.

Recommendations for standards of monitoring during anaesthesia and recovery 2021: Guideline from the Association of Anaesthetists.

This guideline updates and replaces the 5th edition of the Standards of Monitoring published in 2015. The aim of this document is to provide guidance on the minimum standards for monitoring of any patient undergoing anaesthesia or sedation under the care of an anaesthetist. The recommendations are primarily aimed at anaesthetists practising in the UK and Ireland, but it is recognised that these guidelines may also be of use in other areas of the world. Minimum standards for monitoring patients during anaesthesia and in the recovery phase are included. There is also guidance on monitoring patients undergoing sedation and during transfer. There are new sections specifically discussing capnography, sedation and regional anaesthesia. In addition, the indications for processed electroencephalogram and neuromuscular monitoring have been updated.

Rational performance metrics for operating theatres, principles of efficiency, and how to achieve it.

BACKGROUND: Several performance metrics are commonly used by National Health Service (NHS) organizations to measure the efficiency and productivity of operating lists. These include: start time, utilization, cancellations, number of operations and gap time between operations. The authors describe reasons why these metrics are flawed, and use clinical evidence and mathematics to define a rational, balanced efficiency metric. METHODS: A narrative review of literature on the efficiency and productivity of elective NHS operating lists was undertaken. The aim was to rationalize how best to define and measure the efficiency of an operating list, and describe strategies to achieve it. RESULTS: There is now a wealth of literature on how optimally to measure the performance of elective surgical lists. Efficiency may be defined as the completion of all scheduled operations within the allocated time with no over- or under-runs. CONCLUSION: Achieving efficiency requires appropriate scheduling using specific procedure mean (or median) times and their associated variance (standard deviation or interquartile range) to calculate the probability they can be completed on time. The case mix may be adjusted to yield better time management. This review outlines common misconceptions applied to managing scheduled operating theatre lists and the challenges of measuring unscheduled operations in emergency settings.

ANTECEDENTES: Las organizaciones del National Health Service (NHS) suelen utilizar varias métricas de rendimiento para medir la eficiencia y la productividad de las listas quirúrgicas. Estas incluyen: hora de inicio, utilización, cancelaciones, número de operaciones, e intervalo de tiempo entre casos. Describimos las razones por las cuales estas métricas son defectuosas y nuestro objetivo es utilizar la evidencia clínica y las matemáticas para definir una métrica racional y equilibrada de eficiencia. MÉTODOS: Realizamos una revisión descriptiva de la literatura sobre la eficiencia y la productividad de las listas de cirugía electiva del NHS. Nuestro objetivo era racionalizar la mejor manera de definir y medir la eficiencia de una lista quirúrgica, y describir estrategias para lograrlo. RESULTADOS: Actualmente existe una gran cantidad de literatura sobre cómo medir de manera óptima el rendimiento de las listas quirúrgicas electivas. La eficiencia puede definirse completando todas las operaciones programadas dentro del tiempo asignado, sin excesos, ni infrautilización del tiempo. CONCLUSIÓN: Para lograr la eficiencia se requiere una programación adecuada utilizando la media (o mediana) de tiempo específica por caso y su varianza asociada (desviación estándar o rango intercuartílico) para calcular la probabilidad de que la programación se pueda completar a tiempo. Se puede ajustar el case mix para obtener una mejor gestión del tiempo. Esta revisión presenta conceptos erróneos frecuentemente aplicados a la gestión de listas de quirófanos programadas y los desafíos de medir operaciones urgentes no programadas.

Rational planning of operating lists: a prospective comparison of 'booking to the mean' vs. 'probabilistic case scheduling' in urology.

The efficient use of operating theatres requires accurate case scheduling. One common method is 'booking to the mean'. Here, the mean times for individual operations are summed to approximate the time allocated to the list. An alternative approach is 'probabilistic scheduling'. Here, the means and standard deviation of the individual case times are combined to estimate the probability that the planned list will finish on time. This study assessed how probabilistic booking would have changed list utilisation, over-running and case cancellations in 60 urology lists during eight months that had been 'booked to the mean'. Booking to the mean resulted in 53/60 (88%) lists over-running and correctly predicted the finish times in just 13% of lists. Out of 264 patients, 36 (14%) were cancelled on the day due to over-runs in 24/60 (40%) lists. In contrast, probabilistic scheduling correctly predicted an over-run or under-run in 77% of lists, which would have allowed the case mix to be adjusted to prevent cancellation and optimise utilisation.

Mathematical model of the risk of drug error during anaesthesia: the influence of drug choices, injection routes, operation duration and fatigue.

The incidence of an anaesthetic drug error can be directly observed in large trials. In an alternative approach, we developed a probabilistic mathematical model in which the anaesthetist is modelled as a 'fallible entity' who makes repeated drug administration choices during an operation. This fallibility was factored in the model as an initial 'intrinsic error rate'. The choices faced included: dose; timing of administration; and the routes available for injection (e.g. venous, arterial, epidural, etc.). Additionally, we modelled the effect of fatigue as a factor that magnifies the cumulative error rate. For an initial intrinsic error rate of 1 in 1000 (which from first principles we consider a reasonable estimate), our model predicted a cumulative probability of error over a ~12 h operation of ~10%; that is, 1 in 10 operations this long results in some drug error. This is similar to the rate reported by large observational trials. Serious errors constitute a small fraction of all errors; our model predicts a Poisson distribution for the uncommon serious errors, also consistent with independent observations. Even modest assumptions for the development of fatigue had a dramatic and adverse impact on the cumulative error rate. The practice implications of our modelling include: exercising caution or avoiding starting work if under par; added vigilance in unfamiliar environments; keeping anaesthetic recipes simple; and recognising that operation durations > 5-6 h constitute a time of exaggerated risk. These implications are testable predictions in observational trials. If validated, our model could serve as a potential research tool to investigate the impact of safety interventions on the rate of intrinsic error using simulation.

Legal and ethical implications of defining an optimum means of achieving unconsciousness in assisted dying.

A decision by a society to sanction assisted dying in any form should logically go hand-in-hand with defining the acceptable method(s). Assisted dying is legal in several countries and we have reviewed the methods commonly used, contrasting these with an analysis of capital punishment in the USA. We expected that, since a common humane aim is to achieve unconsciousness at the point of death, which then occurs rapidly without pain or distress, there might be a single technique being used. However, the considerable heterogeneity in methods suggests that an optimum method of achieving unconsciousness remains undefined. In voluntary assisted dying (in some US states and European countries), the common method to induce unconsciousness appears to be self-administered barbiturate ingestion, with death resulting slowly from asphyxia due to cardiorespiratory depression. Physician-administered injections (a combination of general anaesthetic and neuromuscular blockade) are an option in Dutch guidelines. Hypoxic methods involving helium rebreathing have also been reported. The method of capital punishment (USA) resembles the Dutch injection technique, but specific drugs, doses and monitoring employed vary. However, for all these forms of assisted dying, there appears to be a relatively high incidence of vomiting (up to 10%), prolongation of death (up to 7 days), and re-awakening from coma (up to 4%), constituting failure of unconsciousness. This raises a concern that some deaths may be inhumane, and we have used lessons from the most recent studies of accidental awareness during anaesthesia to describe an optimal means that could better achieve unconsciousness. We found that the very act of defining an 'optimum' itself has important implications for ethics and the law.

A national survey of out-of-hours working and fatigue in consultants in anaesthesia and paediatric intensive care in the UK and Ireland.

The tragic death of an anaesthetic trainee driving home after a series of night shifts prompted a national survey of fatigue in trainee anaesthetists. This indicated that fatigue was widespread, with significant impact on trainees' health and well-being. Consultants deliver an increasing proportion of patient care resulting in long periods of continuous daytime duty and overnight on-call work, so we wished to investigate their experience of out-of-hours working and the causes and impact of work-related fatigue. We conducted a national survey of consultant anaesthetists and paediatric intensivists in the UK and Ireland between 25 June and 6 August 2018. The response rate was 46% (94% of hospitals were represented): 84% of respondents (95%CI 83.1-84.9%) contribute to a night on-call rota with 32% (30.9-33.1%) working 1:8 or more frequently. Sleep disturbance on-call is common: 47% (45.6-48.4%) typically receive two to three phone calls overnight, and 48% (46.6-49.4%) take 30 min or more to fall back to sleep. Only 15% (14.0-16.0%) reported always achieving 11 h of rest between their on-call and their next clinical duty, as stipulated by the European Working Time Directive. Moreover, 24% (22.8-25.2%) stated that there is no departmental arrangement for covering scheduled clinical duties following a night on-call if they have been in the hospital overnight. Overall, 91% (90.3-91.7%) reported work-related fatigue with over half reporting a moderate or significantly negative impact on health, well-being and home life. We discuss potential explanations for these results and ways to mitigate the effects of fatigue among consultants.