#TheAnaesthesiaBlog

The effect of COVID-19 infection on peri-operative mortality was characterised by the first CovidSurg study, which found an increased postoperative mortality across an international cohort if surgery was undertaken within the first 7 weeks following infection. In this issue, a service evaluation examined perioperative mortality in an English cohort (via OpenSAFELY) of over 3.5 million patients comparing pre-pandemic, pre-vaccination, and post-vaccination groups. It found that the same pattern of increased postoperative mortality following infection was present in both vaccinated and pre-vaccination cohorts, but that the absolute risk of death was much lower in England than CovidSurg data suggested. The implication of this is that in contrast with previous guidance, low risk patients might benefit from a shorter delay to surgery, in an approach more in line with other acute respiratory infections. An accompanying editorialexplores whether even modest changes in mortality can have large effects, and advocates considering individual risks and benefits.

The first publication from the NAP7 study analyses the results of the activity survey – a snapshot of all cases performed under the care of an anaesthetist during four days in November 2021. They find several important trends in patient characteristics – compared to NAP5 in 2013 patients are older, have a higher BMI, and are more comorbid. Anaesthetic practice has also changed, with an increase in total intravenous anaesthesia cases from 8% to 26%, but a relative stable proportion of regional anaesthesia cases. Overall, these data show an increase in the complexity of anaesthetic patients, which is likely to have substantial effects on anaesthetic and peri-operative services. An editorialuses this data to explore the larger term trends in staffing and productivity within the NHS and explores the potential system wide changes which could improve productivity.

Despite substantial advancements in human and technological factors associated with anaesthesia, tracheal intubation remains a fundamentally high-risk activity, associated with rare but potentially catastrophic adverse events. This multicentre randomised controlled trial comparing first attempted tracheal intubation using direct and video-laryngoscopes found that successful first pass intubation was significantly more common with a MacGrath videolaryngoscope using a Mac blade than with direct laryngoscopy (94% versus 82%). From secondary analyses, they found this effect persisted when limiting the analysis to consultants only, and that the total two attempt intubation failure rate was 4% for direct laryngoscopy and 1% for the McGrath. Whilst these results are consistent with other results published examining similar questions, this study stands out as showing a substantial benefit for videolaryngoscopy in an undifferentiated but low risk population in a large well-conducted trial where the benefits might have been expected to be limited. The accompanying editorial has generated much discussion by exploring the potential pitfalls of a first line videolaryngoscopy approach has advocating for ongoing training in direct approaches.

Felton et al. report a study examining whether volatile organic compounds could be used as biomarkers for ventilator-associated pneumonia, finding that there were several candidate compounds. A test which could reliably rule this out would be very valuable in minimising inappropriate antibiotic exposure. An editorial explains the difficulties with finding and assessing biomarkers in the context of inconsistent results between studies.

A randomised controlled trial found that the use of pneumatic compression stockings reduced post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy, with associated reductions in vasopressor use and no complications associated with their use. With further validation this represents a potential avenue for a non-invasive intervention to help maintain better cardiovascular stability during anaesthesia, which would be particularly valuable in this older patient group.

Concern about how to teach regional anaesthesia to novice practitioners, given the substantial learning curve and many individual micro-skills, informs Chuan et al. reporting their evaluation of a novel virtual reality trainer for regional anaesthesia, finding substantial inter-individual variability in learning. Also published in this issue was new guidance from the Association of Anaesthetists regarding the management of vagus nerve stimulation therapy in the peri-operative period, alongside this month’s Reviewer Recommendations which explains how to undertake and reportpatient and public involvement in research.

Finally, it was great to see the journal represented at the ANZCA ASM with a variety of Editors, Associate Editors and Anaesthesia Reports Editors in attendance. Booking for Annual Congress 2023 in Edinburgh is now open, and we hope to see you there too!

Paul Bramley and Andrew Klein

We are delighted to present an original article and systematic review on the use of risk scores to predict 30-day mortality after surgery in this month’s issue of Anaesthesia. Darbyshire et al. evaluated the predictive ability of three novel risk scores for 30-day mortality after emergency bowel surgery. The results showed that the individual scores were reasonable predictors of mortality, but they were poorly calibrated. A logistic regression model that incorporated age, National Early Warning Score, Laboratory Decision Tree Early Warning Score, and Hospital Frailty Risk Score demonstrated good discrimination and calibration but was slightly less effective than the National Emergency Laparotomy Audit score. Meanwhile, in a systematic review, Vernooij et al. assessed prediction models for 30-day postoperative mortality in non-cardiac surgical cohorts. Although 10 models were evaluated, they were considered to have unclear or high risk of bias in their development. However, the surgical outcome risk tool (SORT) demonstrated the best combination of predictive performance and clinical usability. The accompanying editorial emphasises the importance of high predictive accuracy and clinical usability in the adoption of pre-operative mortality risk prediction models in routine clinical practice.

In older adult patients, postoperative cognitive disorders are a common occurrence. Although neuropsychiatric assessment is the gold standard for diagnosis, it is expensive and often unavailable in resource-limited healthcare settings. Zuylen et al. conducted a single-centre prospective observational study comparing simple neurocognitive tests, such as the Modified Telephone Interview for Cognitive Status and Montreal Cognitive Assessment, to neuropsychiatric testing. However, the results showed limited agreement between the tests (Fig. 1), indicating that these simplified tests should not be used in isolation to diagnose postoperative neurocognitive disorders.

Aerosol-generating procedures are high risk interventions for airborne transmission of pathogens. Shrimpton et al.investigated the risk of aerosol generation during awake tracheal intubation and nasoendoscopy procedures, and found that they can generate high concentrations of respiratory aerosol, especially when lidocaine is sprayed on the vocal cords or the bronchoscope is passed through the vocal cords. The authors suggest that airborne infection control precautions are recommended for such procedures if respirable pathogens cannot be confidently excluded.

In this issue of Anaesthesia, two studies on the use of dexmedetomidine are presented. The first study examines the introduction of a nurse-led sedation service for magnetic resonance imaging in children using intravenous and intranasal dexmedetomidine. The study found an impressive overall sedation success rate of 98.4%, concluding that paediatric sedation with dexmedetomidine can be both safe and successful. The second study investigates the effect of dexmedetomidine on delirium after cardiac surgery. While the study found no significant difference in the incidence of delirium between the dexmedetomidine and saline groups (Fig. 2), the use of dexmedetomidine was associated with an increased risk of postoperative renal impairment.

In the wake of the remifentanil shortage, Hughes et al explore alternative options for total intravenous anaesthesia, in a comprehensive narrative review. The review presents a range of compelling opioid (Fig. 3) and non-opioid analgesic (Fig. 4) options for TIVA, along with detailed explanations of their pharmacokinetic profiles. The authors’ thorough analysis is a valuable resource, providing an opportunity to explore lesser-known analgesics and broaden our practice.

Open science is a movement towards making scientific research, data, and dissemination freely accessible to all without any barriers or restrictions. It fosters collaboration and encourages the sharing of information and ideas among researchers, while also promoting the use of open-source software and tools to facilitate scientific research. In this issue, our editorial  explores the benefits and drawbacks of open science and takes a closer look at its current status in anaesthesia.

This issue delves into two vital aspects of ICU management: viral infections and end of life care. Viral infections form a significant part of ICU workload, with managing them becoming more challenging due to increased availability of molecular diagnostics. This review provides an overview of managing viral infections in critical care, including complications, rare and emerging viruses, and the importance of infection control to prevent nosocomial viral transmission. In another review, Gutiez et al. address ethical dilemmas around withholding and withdrawing life-sustaining treatment, balancing paternalism and shared decision-making, legal challenges, conflict resolution, and practical issues. This review clarifies the differences between withdrawing/withholding treatment and euthanasia, offers practical suggestions for using sedation and analgesia, and advocates for family inclusion in decision-making. The article also proposes a step-escalation approach to family conflict and highlights the importance of communication skills in medical and nursing training.

This month’s Reviewers Recommendations examines how to measure academic impact.  Measuring academic impact is complex and multifactorial. This article discusses the strengths and weaknesses of existing metrics used to quantify or qualify academic impact, from individual researcher level to journal level. It explains that no single measure exists to accurately represent the impact of a researcher or an individual article, and thus a holistic approach drawing together multiple parameters should be taken to measure academic impact. The full collection of reviewers recommendations can be found here, and is an excellent ‘how to’ manual for all who wish to get involved with research and the communication of scientific fact and opinion.

Finally, don’t miss out on The Association of Anaesthetists Annual Congress 2023 in Edinburgh, from 13th-15th September. This highly anticipated in-person conference offers a wide range of diverse speakers, practical workshops, great clinical content and hands-on experience with the latest technology at the industry exhibition. Early booking is available until August 1st, 2023, so register here now.

Eimear Keane and Andrew Klein

This month, we are delighted to publish a narrative review and guideline on human factors in anaesthesia. The guideline recently received > 11k downloads after being shared widely by Martin Bromiley and holds an Altmetric score of > 200, having been tweeted by 250 users and reported by two news outlets. Publishing a review and guideline together in this way seems to work well, as the review can synthesise and comment on the relevant scientific evidence whilst the guideline builds on this with expert analysis, opinion and consensus. The authors should be congratulated, as the work going into such an endeavour is extraordinary and the content of both papers are clinically useful for doctors and aim to make care for patients safer. In the associated editorial, Professor Marshall takes us through the background to the papers, how views have changed over time and how organisations should continue to move beyond error as a cause of incidents. 

The April issue also contains several articles featuring in our special intensive care collection. A former ICU patient, Catherine White, shares her perspectives following a critical illness in 2006. She describes how things were then, which may come as a shock to some. That said, there remains work to be done to properly embrace multidisciplinary collaboration, eliminate ICU delirium and examine our outcome metrics and the support patients and their relatives are provided well beyond discharge from hospital. Dr Matt Morgan reflects on 70 years of modern critical care, highlights the importance of all the associated papers and calls for more routine use of patient-centred and functional outcomes. This month, we have included reviews on the management of traumatic brain injury in the non-neurosurgical ICU and the problems around making a clinical diagnosis in ICU.

Around 70% of surgical patients are prescribed postoperative opioids, but there is much we do not know about opioid type and persistent use rates. This new retrospective cohort study from Lam et al. compared oxycodone and tapentadol in > 100k patients discharged from one of four Australian centres (Fig. 1). They found that, after controlling for socio-economic characteristics, comorbidities and other established risk factors, there were lower odds of patients developing persistent postoperative opioid use with tapentadol compared with oxycodone in those that received modified release opioids at discharge and those undergoing orthopaedic surgery. The associated editorial from Bicket et al. set the results in the context of the US opioid epidemic and provide seven principles for effective acute peri-operative pain management. The solutions provided might not be simple and they go far beyond substituting one drug for another, but they do make sense.

Persistent pain after breast cancer surgery has important socio-economic and healthcare implications. From their prospective cohort study of 210 patients, Tan et al. developed a risk-stratification model for persistent pain after breast cancer surgery by analysing a wide range of potential risk factors (Fig. 2). Four months after surgery, persistent pain was present in 64% of patients and was independently associated with younger age, diabetes, increased pre-operative pain score at sites other than the breast, previous mastitis and higher perceived stress scale score. Can virtual reality be used for cancer-related neuropathic pain? This new pilot RCT from Chuan et al. might be the first step towards answering that question, as it demonstrates feasibility of recruitment for a definitive trial. Elsewhere, Diallo et al. review the predictors and impact of postoperative atrial fibrillation following thoracic surgery and Xu et al. compare the ESP and paravertebral block for laparoscopic nephro-uretectomy.

Finally, this month’s Reviewer Recommendations tackles retrospective cohort studies. These papers account for a large proportion of submissions to the journal, but the acceptance rate is low as compared with other study design types. This guide lists and discusses: their advantages and disadvantages; the difference between research, audit and service evaluation; how to collect and analyse data; considerations for databases; statistical corrections; and manuscript preparation and publication. The full collection can be found here, and is an excellent ‘how to’ manual for all who wish to get involved with research and the communication of scientific fact and opinion.

Mike Charlesworth and Andrew Klein

We are delighted to announce that our 2024 special supplement will focus on sustainable healthcare and the role of the anaesthetist. This month’s issue shows how important this theme is also in 2023. First, Waspe and Orr review regulatory guidelines for environmental risk assessment of propofol in wastewater. They outline the two phases of an environmental risk assessment for medicinal products and remind us that other drugs such as: erythromycin; clarithromycin; ibuprofen; diclofenac; ethinylestrodiol; metformin; and propranolol have the highest ecotoxicological risk to the surface water environment. In the associated editorial, White, Fang and Shelton outline the propofol life cycle (Fig. 1). Their interpretation is that ‘worst-case’ propofol wastewater exposure estimates fall far below the threshold at which aquatic species sustain adverse effects. They call on all anaesthetists to continuously make incremental progress in understanding and lowering our professional environmental impact.

Medicinal nitrous oxide use has well described consequences for the environment and this new editorial from Lucan et al. accompanies a paper from 2022 by Pinder et al. They remind us that there is no simple switch from nitrous oxide for labour analgesia and this makes the balance between patient choice and environmental concern a delicate one. They call for more widespread implantation of ‘cracking devices’ in delivery units across the UK. Getting it right first time is key to reducing out environmental impact, and this new editorial from Coldwell and Craig outlines how this might be done by better deploying anaesthetic skills and workforce. One interesting point relates to who trainees should anaesthetise with distant supervision and how this has changed over time. There remain many questions and concerns about the anaesthetic workforce, and we will no doubt see this becoming an important issue over the coming years. 

Tranexamic acid is a useful adjunct to reduce peri-operative bleeding and the need for blood transfusion. This new population-based study from Taiwan looked at 226,719 total knee replacements during 2010–2019. They found that tranexamic acid treatment was associated with a 50% decrease in red blood cell transfusion rates, with no increased risk of all vascular outcomes or in-hospital mortality. However, they did identify an association between TXA use and an increased risk of renal injury (Fig. 2). In the associated editorial, Bailey summarises the evidence for tranexamic acid in total knee arthroplasty. He argues it is effective, affordable and safe, and that its use should be enshrined in routine practice.

This new multicentre retrospective cohort study from Suleiman et al. tackles an old question – which reversal agent is best? They included 83,250 patients from 2016–2021 and found no association between the choice of the primary reversal drug and postoperative respiratory complications or advanced healthcare utilisation. Equivalence and non-inferiority were also established between sugammadex and neostigmine. Another therapy under question is pre-operative intravenous iron before major abdominal surgery for iron deficiency anaemia. This secondary analysis of the PREVENTT trial found no beneficial effect of the use of intravenous iron compared with placebo, regardless of the metrics to diagnose iron deficiency, on postoperative complications or length of hospital stay. There are several other clinical implications of this research that are discussed in depth in the associated free podcast. Another important paper is a new multidisciplinary consensus statement on the use of cerebral computed tomographic angiography as an ancillary investigation to support a clinical diagnosis of death using neurological criteria. Cerebral CT angiography has been shown to have 100% specificity in these circumstances and is an investigation available in all acute hospitals in the UK. There are 10 recommendations which are essential reading for all intensivists, radiologists, radiographers and neurosurgeons.

Elsewhere we have: a randomised controlled trial of intravenous dexmedetomidine added to dexamethasone for arthroscopic rotator cuff repair and duration of interscalene block; a review of cognitive aids in the management of clinical emergencies; a review of postoperative systemic inflammatory dysregulation and corticosteroids; and a systematic review of dexmedetomidine for adult cardiac surgery.

This month, we have two ‘Reviewer Recommendations’ papers which tackle how to perform and write a trial sequential analysis and how to write a Science Letter for Anaesthesia. Our aim is that these articles not only help those who wish to submit their work to the journal, but they are of wider use to all who wish to learn more about research methods and how papers are published. 

Finally, we are advertising for new Editors and a LMIC-based Editorial Fellow. We hope you will consider joining our team.

Mike Charlesworth and Andrew Klein

January is one of our favourite times at the journal as we publish our special supplement issue of focussed reviews under the umbrella of a wider theme. This year, the theme is ‘specialist intensive care for the generalist’, and it could not come at a better time. Matt Morgan introduces the background problems tackled by the reviews in ‘Intensive care 2.0‘. One way of looking at these articles is that, whilst past supplements tended to report on what we know, this contribution, led by experts, focusses instead on uncertainties. Alas, it could be argued that 9 in 10 critical care interventions are not truly evidence-based. The second article has already attracted a lot of attention on Twitter following publication and is about patient reflections on intensive care medicine. It is written by Catherine White who had a critical illness in 2006 and has spent the last 15 years trying to make patient experience in intensive care better. There are many things we must strive to improve such as eliminating ICU delirium, but the toll of what we ask of ICU staff must also be considered.

The first of the reviews from Van Eldere and Pirani tackles the liver. They outline the principles behind how to interpret deranged liver function tests, common primary causes of liver failure in ICU, management considerations, hepatic encephalopathy, coexisting renal failure management, coagulation, gastrointestinal haemorrhage, infection and extracorporeal liver support devices. Overall however, intensive care management of liver dysfunction is largely supportive and the usual evidence-based principles of general critical care management are helpful. Wiles et al. provide up-to-date evidence on the management of traumatic brain injury in the non-neurosurgical ICU. Whilst some specialist interventions might not be available in this setting, high quality care for these patients can still be ensured by following the principles set out in this article. Tanaka Gutiez et al. discuss end of life care in ICU, including issues around ethics, limiting life-sustaining therapies, analgesia and sedation around the time of death, family discussions and the law. Some practical tips are provided on how to approach the family as well as eight end-of-life practice recommendations.

Maternity critical care is very much a developing area and this new review from Cranfield et al. tells us how to get it right (Fig. 1). It focusses on recognition of critical illness, where care should be delivered, critical care strategies, timing of birth, teamworking and implications for resource limited settings. There is an urgent need here for the evidence base to catch up with other areas of intensive care medicine. Following on from the recent pandemic, our knowledge of how to treat respiratory viral infections in ICU is no doubt much improved. Conway Morris and Smielewska provide everything we need to know about this as well as other viral infections such as those that are blood-borne, enteric, reactivated and unusual/rare. The only certainty is that viruses will continue to wreak havoc in ICUs for years to come given the effects of climate change, habitat invasion and global interconnectedness.

Figure 1 Benefits and compromises associated with different locations for maternity critical care. PET, pre-eclampsia; MEOWs, maternal early obstetric warning scores.

Most of us think we know about acute kidney injury and renal medicine in ICU, and this review from Boyer et al. tackles all the usual areas but also discusses the emerging role of the nephrologist in the ICU. There is much left to study, including peri-operative biomarker-guided interventions, which promise to improve postoperative outcomes in patients who might have in the past developed a more severe acute kidney injury. Renal disease in ICU is common, and there are many areas where we can improve care for patients today. Finally, Pisciotta et al. discuss the intricacies of diagnosis in the ICU (Fig. 2). In a world with increasing availabilities of ‘tests’, they emphasise the importance instead of bedside clinical examination and spending time with the patient.

Figure 2 The diagnostic process and metacognition. Diagnostic process phases (in blue) are interspersed with metacognitive timeouts (in orange).

The February issue is also now available online and the first paper is the largest of its kind to look for an association between prenatal exposure to anaesthesia and impaired neurodevelopmental outcomes. They included the parents of 129 exposed and 453 unexposed children and conclude that, in the general population, prenatal exposure to anaesthesia for non-obstetric surgery is not associated with clinically meaningful impairments in neurodevelopmental outcomes (Fig. 3). In the associated editorial, Kearns et al. provide some practical considerations for non-obstetric surgery in the pregnant patient. It sets the new paper by Bleeser et al. in the context of previous related research. Overall, they argue that these new data provide further reassurance for parents and healthcare staff in what remains an area that has been under-researched.

Figure 3 Primary and secondary outcomes. Diamonds and error bars represent the estimate for the mean difference of t-scores (exposed minus unexposed) and their 95%CIs. Inverse probability of treatment weighting (panel a) was used to reduce bias by confounders. In the sensitivity analyses, other methods to reduce bias by confounders were used (panels b and c). Data were also analysed without taking confounders into account (panel d). BRIEF, Behavior Rating Inventory of Executive Function; CBC, Child Behavior Checklist.

Previously we published articles on aerosol generating procedures and fasting before surgery. This month, we have two important editorials on these topics. Checketts reminds us how multiple hospitals have turned the relationship between fluid fasting and safety in anaesthetic practice on its head. It seems that this is a good example of where guidelines have not kept pace with clinical practice. Speaking of which, Harrison et al. discuss the interface between research, guidance and implementation for aerosol-generating procedures. They list the changes in NHS England guidance occurring between January–May 2020 and then the final version in June 2022.

Elsewhere we have: a randomised non-inferiority trial of ultrasound-guided genicular nerve blockade vs. local infiltration analgesia for total knee arthroplasty; a review of anaesthesia for vascular emergencies; and a review of the management of thoracic trauma. This month’s Reviewer Recommendations includes guides to conducting a Delphi consensus process and collaborative research studies.

As we return from a fantastic Winter Scientific Meeting in London, it is worth reflecting on our highlights, which include the launch of new human factors guidelines, a summary of our new ICU special issue, presentation of early NAP7 data and a live trauma simulation. We managed to catch Dr Fiona Kelly for a quick summary of her new guidelines, which you can now enjoy for free, here.

Mike Charlesworth and Andrew Klein

This new guideline is without doubt one of the most important papers from 2022 and essential reading for all. Oesophageal intubation during attempted tracheal intubation could happen to any one of us, yet traditional teachings and practice might lead to misdiagnosis. The case of Glenda Logsdail demonstrates the very real consequences when things go wrong. The key elements of the paper are the 11 core recommendations, the criteria for ‘sustained exhaled carbon dioxide’ and an algorithm for what should happen when these criteria are not met. Because many will not be skilled with airway ultrasound and because most will not have even seen an oesophageal detector device, the guideline reinforces the recently published Association of Anaesthetists recommendation for flexible bronchoscopes to be available for every general anaesthetic. The paper is free for all forever and as we saw live at Annual Congress, the associated cognitive aids located in the right place at the right time might just save a life. Ahmad and Wong provide the accompanying editorial and discuss the likely real-world impact of the guidelines. Afterall, it is extremely difficult to quantify true implementation and adherence of the recommendations provided.

If the PUMA guideline was the most important paper from this year, the results from NAP7 promise to deliver the same in 2023. But before all is revealed, this new paper takes us through the methods in detail. That the authorship delivered the project during the COVID-19 pandemic is a remarkable achievement and underscores the drive and determination behind the whole team. Not only that, the NAP7 infrastructure was activated to monitor the impact of COVID-19 on anaesthetic and surgical activity between October 2020 and January 2021 (ACCC-track). One of the many difficulties faced was to derive a unified definition of ‘peri-operative cardiac arrest’, which has been a source of controversy for many years. Although these events are rare and there is a great deal to learn from the analysis of individual cases, the project will also report some interesting trends at a national level with implications for all doctors, patients and policy makers.

Was it worth treating patient with COVID-19 in critical care areas? This new prospective single centre study from Schallner et al. found that direct medical costs for the treatment of COVID-19 patients were higher than for other critically ill patients, which was not exclusively due to longer length of stay (Fig. 1). Despite these high costs, they conclude the associated care to be cost-effective and beneficial regarding QALYS gained in relation to other medical measures. In the associated editorial, Pandit highlights several limitations of the analysis which suggest that we should not allow these data to inform public policy. 

Postoperative morbidity following colorectal surgery can only be improved if it is measured and modelled. This new study from Bedford et al. describes the development and internal validation of the PQIP colorectal risk model. It demonstrates good calibration to risk-adjust postoperative day 7 morbidity defined by the POMS in the setting of elective major colorectal surgery with discrimination performance superior to published morbidity risk models. In the associated editorial, Coulson et al. set the work in its context and describe a pyramid model of investigation into unexpected variation is proposed (Fig 2.). 

This new study aims to break the cycle of unnecessary lengthy periods of pre-operative fasting by using iterative ‘plan-do-study-act’ methods. They managed overall to reduce the median liquid fasting time from 12 h to 2 h, which is in keeping with international guidance. The key factor here is use of the term ‘unrestricted’, because putting limits on pre-operative clear fluid quantity and time presents logistical issues for staff, patients and hospitals. Is pre-oxygenation with high flow nasal oxygen easier for the anaesthetist and more comfortable for patients as compared with a facemask? This new RCT from Merry et al. finds this to be the case albeit with no clinically relevant differences in effectiveness (Fig. 3).

Elsewhere we have: a review of obstetric anaesthesia emergencies; a review of peri-operative frailty; and a comparison of standard and flexible tip bougies for tracheal intubation using a non-channelled hyperangulated videolaryngoscope. Finally, Shelton and Goodwin provide a guide on how to plan, report and get your qualitative study accepted. Teaching in this important area is scarce in undergraduate and postgraduate medical curricula, but this paper aims to bring us all up to speed on aspects such as reflexivity, generalisability and credibility. That’s all for 2022, but make sure you join us next year for WSM23 and look out for our new special supplement issue in the early new year!

Mike Charlesworth and Andrew Klein

Increasing numbers of NHS consultants are voluntarily reducing their time spent delivering contracted direct clinical care. The result is concerning, with experienced clinicians working less hours and retiring early. This new guidance aims to highlight contributory issues and list clear, implementable solutions. One theme is that ‘age’ in anaesthesia should not be perceived negatively and should instead be celebrated. Experienced clinicians have much to offer departments, hospitals and patients, and younger clinicians should think carefully now about how to ‘pace’ careers and continue to work well with age. However, to make the guidance work we all need now to signpost the eight recommendations to departments, colleagues and hospital managers because without action, the workforce gap will continue to increase.

When faced with a theatre list, some cases are plainly more complex than others. The reasons for this might be obvious to us, but less so for patients, surgeons, schedulers and managers. This is where the new OxAnCo score is useful, as it allows for the tacit to be quantified. Importantly, this is not about risk or outcomes, which are different. The score incorporates patient, anaesthetic, surgical and system factors related to complexity and was derived through a survey of clinicians. The authors validated their score prospectively against 688 cases and found a correlation with the grade of anaesthetist. One conclusion must be therefore that we are good already at rating complexity and matching it with resources. This brings the need to implement the score to this end into question. However, it could also be argued that with predicted problems with future workforce planning, a score such as this allows everyone involved with planning elective surgery and resources to read off the same peri-operative page.

We now know that the most environmentally damaging anaesthetic agents are desflurane and nitrous oxide, and we can reduce their use to zero in operating theatres through using alternatives. However, inhaled nitrous oxide continues to be used in maternity units as a first-line strategy for labour analgesia. As well as environmental harm, exhaled nitrous oxide is an important occupational risk for healthcare staff. Thankfully, technology is here to the rescue us and this new paper reports results from the use of catalytic nitrous oxide cracking equipment in clinical practice (Fig. 1). The equipment works and we know that from previous bench experiments. This translational work finds only minor issues with its implementation amongst participating staff. Importantly, ambient nitrous oxide levels were reduced by 71-81%. However, this is following a brief period of coaching and is dependent on parturient cooperation. 

There has been much discussion in the literature and on social media about anaesthetic single syringe admixtures. This new study tests a combination that might be useful for low- and middle-income countries such as South Africa: ketamine; lidocaine; and magnesium. They found that all three drugs were stable in solution and remained so 24 h later. Pharmacokinetic simulations suggested that a 24-h infusion of the described admixture would provide favourable plasma concentrations for analgesic efficacy. There is a theoretical basis for superiority of various modes of mechanical ventilation over others. However, clinical evidence tends to suggest differences in core outcomes are small or negligible. This new randomised controlled trial in patients having lung resection surgery finds that the selection of ventilation mode in the context of lung-protective ventilation had no impact on the occurrence of postoperative pulmonary complications within the first seven postoperative days (Fig. 2). Perhaps rather than the mode of intra-operative ventilation, factors such as patient selection, optimisation and enhanced recovery have a greater bearing on patient outcomes.

During the pandemic, transplant centres undertook few solid organ transplants for a variety of reasons. This new analysis from NHS Blood and Transplant finds that during the first year of the COVID-19 pandemic, hospitals saw an overall decrease in causes of deaths which typically contribute strongly to organ donation and, as such, fewer eligible potential deceased organ donors (predominantly DCD donors) were referred (Fig. 3). However, there were signs that the organ donation and transplantation system performed well despite pressures on the wider healthcare system. In this month’s Reviewer Recommendations, Bramley and Wiles tackle how to perform and write a meta-analysis. If you are planning a systematic review and meta-analysis and you would like to get it accepted at Anaesthesia, read this paper first. Everything is covered.

Elsewhere we have: a review of novel wearable contactless heart rate, respiratory rate, and oxygen saturation monitoring devices; a narrative review of transporting the trauma patient; a state-of-the-art review of management of the acutely unwell child; and a retrospective observational multicentre study of the prevalence of pre-operative anaemia in surgical patients. Finally, you can now book your place at the 2023 Winter Scientific Meeting where we will be hearing all about the recently published PUMA guidelines, NAP7 and our 2023 Supplement in intensive care. 

Mike Charlesworth and Andrew Klein

This month, we are delighted to publish our new special selection of review articles on emergencies in anaesthesia. Some of these reviews appear in the October issue and the others on Early View and in future issues. All are free to access for all, forever! 

First, Matt Wiles lists the evidence for airway management strategies in patients with suspected or confirmed traumatic spinal cord injury. He discusses: airway manoeuvres; manual in-line stabilisation; cricoid force; direct and indirect laryngoscopy; flexible bronchoscopy; and the associated risks of tracheal intubation. Overall, the risk of spinal cord injury during tracheal intubation appears to be minimal even in the presence of gross cervical spine instability. The evidence supporting practice choices is difficult to generalise to clinical practice, and practitioners should choose the tracheal intubation technique with which they are most proficient in the circumstances. 

Spoelder et al. discuss the transport of the patient with trauma, which is a complex process influenced by many factors. Immediate and precise identification of injury severity, with correct prioritisation of medical treatment and identification of the best mode of transport from accident scene to definite care, may impact morbidity and mortality. Edelman et al. bring together the last 5 years of studies reporting the prevalence and commonality of non-technical skills and human factors in airway management guidelines. They found that human factors were generally well represented in airway management guidelines but that further considerations are necessary for future clinical guidelines. McCahill et al. describe high quality basic care for the acutely unwell child, as well as advancements in the field which address issues around low case exposure and maintaining skills in different settings. Anaesthetists play a key role in the team of clinicians caring for sick children, which can be complex. Developments in training, cognitive aids, knowledge sharing and addressing human factors are vital to keep a workforce ‘paediatric ready’ to deal with these important emergencies. 

Prior et al. review six areas of obstetric emergencies: category-1 caesarean section; difficult and failed airway; massive obstetric haemorrhage; hypertensive crisis; emergencies related to neuraxial anaesthesia; and maternal cardiac arrest. They point to a need for more multidisciplinary training and simulation and outline the central role of obstetric anaesthetists in enhancing a culture of peri-delivery safety. Gottesman et al. review the concept of frailty, its epidemiology and approaches to evidence-based peri-operative management in the setting of emergency non-cardiac surgery. In the future there should be: specific focus on applying shared decision-making in time limited emergency surgery situations; optimal multidisciplinary peri-operative care pathways; effective frailty-friendly analgesic regimens; and effective physical and cognitive recovery after surgery. Finally, Shah et al. review the past, present and future of major haemorrhage.  They discuss: mechanisms; transfusion support; blood components;  ratios; pharmacological interventions; monitoring; and directions for future research (Fig. 1).

In the October issue, Sajayan et al. present their analysis of a national difficult airway database (Fig. 2). They find that unanticipated difficult airway management continues to occur despite airway assessment, and the rate of critical incidents in this cohort of patients is high. As has been reported before, there is still insufficient utilisation of safe techniques such as awake tracheal intubation when a difficult airway is anticipated. In the associated editorial, Smith and Rosenstock ask whether difficult airway cards help if practice doesn’t change?Anticipating airway management difficulties is an imperfect science, but we must better match the available techniques with patients identified or predicted to be at risk. 

This new prospective study from Kohse et al. has been extremely well received already on social media, with over 500 likes for one tweet! They developed a multivariable model and score that associates intubation-related characteristics with subsequent issuing of a difficult airway alert after videolaryngoscopy, tailored to be used as a classification tool to grade difficult videolaryngoscopic intubation (Fig. 3). It demonstrates high discrimination and even outperformed the Cormack–Lehane classification. Will you be using it? 

In addition, we have: a systematic review of the analgesic benefits of the quadratus lumborum block in total hip arthroplasty; a review of mechanical ventilation in patients receiving extracorporeal membrane oxygenation; a study of nocebo language in anaesthetic patient written information; a randomised controlled trial of interscalene block with 10 ml or 20 ml levobupivacaine 0.25% in patients undergoing arthroscopic shoulder surgery; and a study of the measurement of aerosols using a real-time sensor network. 

Shelton and Kearsley provide their top tips on how to write and publish a case report in anaesthesia and peri-operative medicine. This article is a must for anyone wishing to write about their interesting cases and achieve publication in a high-quality journal such as Anaesthesia Reports! We hope you enjoyed the recent Annual Congress 2022 meeting in Belfast as we did. Here are those top 10 article from 2021, which are all free to download forever. Congratulations to the COVIDSurg collaborative, who achieved three spots in the countdown, including paper of the year!

Mike Charlesworth and Andrew Klein

It is not clear yet why facemask ventilation becomes easier following neuromuscular blockade. This new prospective observational study from Lee et al. evaluates changes in tidal volume after administration of neuromuscular blockade and assesses the correlation of this with changes in the vocal cord angle. They found that tidal volume and vocal cord angle during induction of anaesthesia increased after neuromuscular blockade in patients with normal airways. In addition, both insufficiency of ventilation before neuromuscular blockade and improvement after neuromuscular blockade were correlated with vocal cord angle (Fig. 1). They suggest a new role for considering ‘vocal cord status’ to optimise facemask ventilation using neuromuscular blocking drugs. In the associated editorial, Chau and El-Boghdadly discuss the age-old question of whether adequate facemask ventilation should be confirmed before administering a neuromuscular blocking drug. They argue that drug administration is not just about a point of no return but about making the onward journey easier.

In ICU patients, there is a risk of unintended residual neuromuscular blockade and associated complications. This new prospective study from Ross et al. aims to determine the incidence and identify associated factors. They found that it occurred in at least one-third of patients with no difference between postoperative and non-postoperative patients. Worryingly, 63% of New Zealand ICUs rarely test neuromuscular function before tracheal extubation, and 37% never do. In the associated editorial, Bailey simply states that if we cannot measure it, we cannot manage it. Afterall, as far as the administration of neuromuscular blockade is concerned, the ICU environment should be considered the same as the operating theatre.

In the early COVID-19 pandemic, clinical guidelines in all areas of practices were changed beyond recognition in a matter of weeks and months. This new mixed methods study of UK anaesthetists from Shrimpton et al. looks at current practice and perceptions of so called ‘aerosol generating procedures’. The paper is rich with data and insight as well as lessons for the future. For example, some anaesthetists preferred using high level personal protective equipment during pre-operative patient assessment, despite this being at odds with national guidance. Overall, there was a call for more involvement of professional representative bodies, should practice change rapidly in this manner again. Severe maternal morbidity is of interest given that it is expected that historical reductions in maternal mortality might be reversed by increasing risk factors in the general population, such as obesity. This new cohort study from Masterson et al. found that severe maternal morbidity was recorded for about 1% of pregnant women in Scotland. Morbidity was independently associated with: maternal age; BMI; pre-existing morbidity; previous smoking; previous caesarean section; multiple pregnancy; and maternal birth in Africa or the Middle East. Morbidity was associated with delayed hospital discharge, stillbirths and maternal deaths. This paper was featured in the mainstream media with focussed placed on obesity as a significant risk factor. 

There is a need to prioritise equity, diversity and inclusion (EDI) within anaesthesia and medicine as a whole. This position statement outlines the Anaesthesia Editors’ current policies and practices aiming to achieve equity, represent the diversity of our specialty and actively include people engaged with this journal and beyond. We hope this will be an effective starting point towards embedding EDI into everything that the journal does and influences in clinical practice and academia. You can listen to a discussion of the statement, chaired by Association of Anaesthetists CEO Nicky de Beer, here. We all know that desflurane and nitrous oxide are bad for the environment, but how well can their avoidance and other strategies be implemented into clinical practice? This new guidance document from Devlin-Hegedus et al. provides recommendations for all clinicians that can be implemented right now. Will you start doing something different today? 

Another paper featured in major news outlets recently was this narrative review by Pandit et al. on the effect of overlapping surgical scheduling on operating theatre productivity. This might be a strategy that promises much in terms of reducing the waiting list backlog, but this must be balanced against the risk of adverse patient outcomes, safety, training and patient autonomy. You can read the associated press coverage here. Elsewhere we have: a feasibility trial of angiotensin-2 in cardiac surgery; a pooled cross-sectional analysis of trends in country and gender representation on editorial boards in anaesthesia journals; a discussion of SARS-CoV-2 and airway reactivity in children; and a narrative review of the consequences of COVID-19 for chronic pain patients and services.

Finally, this month’s ‘Reviewer Recommendations’ tackles scientific dissemination, with the aim to get research to the people that need it. The authors argue that scientific dissemination is not an optional extra, and there is much work to be done to optimise dissemination tools in academic anaesthesia and peri-operative medicine. 

We have two big papers coming soon from important collaborative groups – PUMA and NAP! Look out for details of publication dates and live broadcasts, with PUMA set to launch their avoidance of oesophageal intubation guideline on Wednesday evening! We will see you for the broadcast on Thursday at 2000 BST. 

Mike Charlesworth and Andrew Klein

We are all familiar with the successes of the National Emergency Laparotomy Audit, but what about those patients where emergency surgery is not appropriate? For five common acute surgical conditions, this new database study from Hutchings et al. compares those who did and did not receive emergency general surgery. They included nearly a million patients who were inpatients between 2010 and 2019. The primary outcome (DAH90) was similar for emergency surgery and non-emergency surgery strategies. However, the most striking result was the influence of frailty, age and number of comorbidities. There is a wealth of information which can be used to assist with discussions between clinicians and patients in the context of emergency general surgery. In the associated editorial, Forrester and Wren put the decision to operate in the context of its epidemiological triad (Fig. 1). They argue for caution when interpreting the results of Hutchings et al. because determining the ‘effectiveness’ of surgery is complex. It seems that more research is required and despite the advantages of instrument variable analysis provides, a prospective randomised study may provider more clarity.

Persistent pain following knee arthroplasty is common, and persistent opioid use in these patients is of concern. This new secondary analysis from Kluger et al. identified pre-operative opioid use, increased body mass index and multiple comorbid pain sites as important risk factors. In the associated editorial, Levy et al. argue for the need to improve opioid prescribing in patients undergoing orthopaedic surgery. They look to the pre-operative period and highlight the fact that opioids are not a benign class of drug. Adverse effects include: increased surgical site infection risk; increased rate of early revision surgery; prolonged hospital stay; and greater likelihood of non-home discharge. 

There has been increasing evidence that lower doses of oxytocin and carbetocin following caesarean section are just as effective as higher doses but with a better side effect profile. This new double-blind, randomised, controlled, non-inferiority trial from McDonagh et al. compared the effect of low- and high-dose carbetocin and low- and high-dose oxytocin on uterine tone intensity at elective caesarean delivery. They found that low-dose carbetocin (20 μg) was non-inferior to high-dose carbetocin (100 μg) for the primary and secondary outcomes of uterine tone intensity at 2, 5 and 10 min after drug administration. Similarly, low-dose oxytocin (0.5 IU) was non-inferior to high-dose oxytocin (5 IU) for these outcomes (Fig. 2). A systematic review and network meta-analysis from Halliday et al. compared ultra-low, low and high concentration local anaesthetic for labour epidural analgesia. They found that ultra-low concentration local anaesthetic is associated with reduced total local anaesthetic dose, shorter first stage of labour and reduced incidence of Apgar < 7 at 1 min compared with low concentration, without compromising maternal analgesia, side-effect profile, satisfaction or neonatal outcomes. A narrative review from McCombe and Bogod brings together learning from 21 years of litigation for anaesthetic negligence resulting in peripartum hypoxic ischaemic encephalopathy. They explore four themes: delay; communication; hypotension following neuraxial anaesthesia; and documentation. Their paper is essential reading for all anaesthetists who work with pregnant women. Earlier this year, Plaat et al. published guidance on prevention and management of intra-operative pain during caesarean section under neuraxial anaesthesia. This new editorial from McGlennan and Christmas explores the background to the paper as well as the clinical context. They remind us that we should always remain open to the possibility of a suboptimal block, and that true failure on behalf of the anaesthetist is failure to recognise and act. 

Elsewhere we have an evaluation of the outcome metric ‘days alive and at home’ in older patients after hip fracture surgery and an editorial praising developments in adult critical care transfer in England, which it is argued is a positive legacy of the COVID-19 pandemic. Finally, Miles and Story provide us with the first a new series of articles of ‘Reviewer Recommendations’. They takes us through the steps of how to design and publish quality science studies, which examine how readily and effectively research findings and guideline recommendations are translated into clinical practice and the outcomes of iterative quality improvement. These articles will become essential reading for anyone who wishes to increase their chances of publication acceptance not just in Anaesthesia, but wherever authors might choose to send their work. 

Make sure you book your place on the upcoming Annual Congress 2022 meeting in Belfast! We hope to see you there for plenty of great content including our annual paper of the year award. 

Mike Charlesworth and Andrew Klein