#TheAnaesthesiaBlog

We often hear calls for the use of PROMs and PREMs in research, and a range of studies report their use in the September issue. O’Carroll et al. report the largest multicentre dataset of day 1 and 30 postpartum recovery metrics using PROMs in patients from the UK. They provide data from 1631 patients in 107 centres and find that complications occur in 1 in 5 postpartum patients following hospital discharge, with 5% of these requiring readmission (Fig. 1). In the associated editorial, Bamber outlines why anaesthetists should care about postnatal care. Perhaps any quality improvement study in obstetrics should look to use a PROM such as ObsQoR as a core outcome, because this standardised tool can help improve postnatal outcomes.

There remains a long way to go to improve prescribing in the postoperative period, and this new national cohort study from Baamer et al. looks for predictors of persistent postoperative opioid use following colectomy in > 90k patients. They found that 16% of patients were prescribed opioids within 90 days of discharge. Three months after surgery, 8% continued to receive opioids. Persistent use was more common in patients who were exposed pre-operatively, and minimally invasive surgical approaches were protective. In the associated editorial, Simpson et al. highlight the prescribed opioid crisis as an impetus to improve postoperative pain management. Several interventions should occur at various stages of the peri-operative pathway (Fig. 2). Do opioids influence patient well-being and anxiety? This new observational study from Eikemo et al. finds that these benefits are relatively rare, with most patients reporting the same or lower levels of ‘feeling good’ after opioids. 

This new systematic review from Tsan et al. has been extremely popular on social media. The authors performed the study to respond to a need to determine whether tranexamic acid in non-cardiac surgery influences thromboembolism. They did not find a difference in the incidence of a composite cardiovascular thromboembolic outcome in patients undergoing non-cardiac surgery between those given prophylactic intravenous tranexamic acid and placebo/no treatment. However, the trial sequential analysis demonstrated that this finding was not conclusive due to inadequate information size. More trials are now justified scientifically. Also on social media, the editorial by Gadsden on reproducibility in the anaesthetic literature has been popular. The context are studies by Kang et al. and Albrecht et al., which although different are valid. He picks out the subtle differences between the studies that may account for their respective findings. 

The hybrid technique utilises videolaryngoscopy and flexible bronchoscopy simultaneously to intubate the trachea. This new registry study in children with a difficult tracheal intubation finds that the hybrid technique had overall success and complication rates comparable with flexible bronchoscopy despite being used more frequently as a rescue device (Fig. 3). Would you use it? Let us know!

Our new position statement sets out best practice in academic medical publishing for Anaesthesia and Anaesthesia Reports. It provides recommendations on our scope, the role of our Editors, authorship, data sharing, EDI, ethics, errors, appeals and research misconduct. We hope this work protects the rights and welfare of research participants, ensures the integrity of study results and aids the communication and dissemination of novel findings into clinical practice. Earlier this year, Darbyshire et al. reported a novel scoring system that performs as well as the NELA score but only requires pre-operative data. This new editorial from Yates et al. sets the work in context and calls for a focus on patient-centres outcomes. They conclude that future studies could use exclusively pre-operative variables to provide mortality predictions for patients who are candidates for emergency bowel surgery but who do not undergo an operation.

Elsewhere we have: the third iteration multispecialty COVID-19 timing of surgery guidelines; an RCT comparing different epidural dosing strategies for labour analgesia; an RCT of prehabilitation for cardiac surgery; and an observational study of aerosol generation and supraglottic airway devices. 

Finally, this month’s Reviewer Recommendations sets out how a narrative review should be written and provides tips on getting such articles accepted for publication. A list of potential topics is provided, and we invite you to pick one of these and get working on it today! We will see you later on today for a live discussion with the authors of a new paper which is all about gastric ultrasound. 

Mike Charlesworth and Andrew Klein

The PUMA guidelines for preventing unrecognised oesophageal intubation were published nearly a year ago, and the paper was arguably one of the most important of 2022. This new editorial from Qureshi et al. builds on this guidance by considering capnography during cardiopulmonary resuscitation, and there has been much discussion from this on social media and in our correspondence pages. There was also much debate on Twitter about the utility of clinical tests for confirming tracheal intubation, which include: tube misting; lung auscultation; 5-point auscultation; and the use of an oesophageal detector device (ODD). The chances are you will not have used or even seen such a device, originally described by Wee as long ago as 1988 but with later variants. The Nunn version is a self-inflating balloon that is connected to the proximal end of the tracheal tube, with reinflation in expiration indicating tracheal placement. This new systematic review suggests the ODD outperforms all other methods tested with a relatively low false positive rate (Fig. 1). Rather than now mandating each anaesthetic room should have an oesophageal detector, the research reinforces a key message from the PUMA guidelines that waveform capnography is fundamental to excluding oesophageal intubation, and use of any one or combination of: tube misting; chest rise/fall; absence of abdominal distension; auscultation; bougie ‘hold up’; maintained saturations; chest radiograph; or recall of the tube passing through the cords, may lead to disaster. 

No discussion of the need to avoid unrecognised oesophageal intubation is complete without mention of videolaryngoscopy, and this month we have two important new papers. First, Kamga et al. report a randomised trial of Flexible nasal bronchoscopy vs. Airtraq® videolaryngoscopy for awake tracheal intubation. Although they failed to demonstrate the non-inferiority of Airtraq videolaryngoscopy vs. flexible nasal bronchoscopy for awake tracheal intubation, it might still be a reliable alternative in certain patients. Second, Choi et al. videolaryngoscopy had a higher first attempt success rate, a shorter time to tracheal intubation and reduced requirement for additional airway manoeuvres than flexible fibrescopy in patients with cervical spine immobilisation using a cervical collar to simulate a difficult airway (Fig. 2). The new editorial from Hansel and El-Boghdadly adds to these papers by discussing the recently published EMMA trial. Although there will likely be further trials, they argue we already know which technique is best, and this is what we should offer our patients. 

This new paper from Yang et al. is a nice randomised controlled trial that contains lots of patients and data, is clinically relevant, and of interest to all anaesthetists. For those seeking to conduct their own trials comparing clinical interventions, the methods used here are a good example of how to proceed. The main conclusion is more patients with a tracheal tube developed postoperative pulmonary complications compared with a supraglottic airway device. An alternative perspective is that there were few differences between groups regarding major complications and core safety outcomes, with the main effects seen in low-grade complications. Given that most included patients were healthy, low risk and undergoing short procedures without significant blood loss, it remains to be seen whether similar trends are seen in higher-risk populations.

We already know from NAP7 that more anaesthetists are using TIVA, and recent NHS data suggests some have made a straight switch to TIVA from desflurane. This editorial examines how nudging clinicians to make sustainable choices is better than prohibition. However, sustainable healthcare is more than volatile management or life-cycle comparisons. As such, in 2024 we will be publishing a special collection of articles that aims to bring all the available evidence on peri-operative sustainability together in one place along with some well-established and newer, perhaps more controversial opinions. 

Elsewhere we have: an editorial on assessing risk in emergency laparotomy; a feasibility trial of erythropoietin in critical care; a trial of nociception index for gynaecological laparotomy; a cohort study of new persistent sedative use after surgery; and a review of chronic pain after lung surgery. In this month’s Reviewer Recommendations, Hughes et al. provide guidance on how best to produce meaningful and visually pleasing figures. You can catch up with this special collection of articles here. You can also listen to all our podcasts here, which have now received >42k downloads. We have published four new episodes in just the last month!

Mike Charlesworth and Andrew Klein

The association between ethnicity and outcomes in obstetrics is well known, but there has been little published about its relationship with obstetric anaesthetic care. This new national cohort study of women who gave birth between 2011–2021 from Bamber et al. finds differences between ethnic groups in rates of general anaesthesia received by women who had caesarean births and in rates of neuraxial anaesthesia received by women who had vaginal births (Fig. 1). In the associated editorial, Lee and Palanisamy examine parallels and paradoxes with care in the USA. Although this is the first study of this kind outside the USA, the overall themes seem to be pervasive. Some may suggest the two healthcare systems are different for many reasons, but it is argued instead that there are similar factors at play requiring similar solutions.

The New Zealand Early Warning Score (NZEWS) is a blended EWS system developed in Wellington Regional Hospital, Wellington, New Zealand and subsequently implemented in every public and private hospital as part of the national patient deterioration programme. The primary objective of this new study from Mohan et al. was to validate the ability of NZEWS to predict serious adverse advents. They found that NZEWS is similar to NEWS in discriminating between patients at risk of serious adverse events, and that blended NZEWS system is safe, accurate and fit for purpose. In the associated editorial, Murali and Inada-Kim highlight the global picture as well as the use of single parameters vs. aggregate scoring. They argue that aggregate rather than blended early warning scores should remain the method of choice for the detection of the deteriorating patient in hospitals.

Is it possible to predict pain after major surgery? This new secondary analysis from Armstrong et al. and the PQIP delivery team shows the development and validation of a prediction model for severe pain on postoperative day 1 after major, non-cardiac surgery which utilises only pre-operative patient data. This is the first attempt to systematically develop a peri-operative pain prediction model using such a large, high-quality dataset in a mixed surgical population (Fig. 3). In the associated editorial, Abdallah et al. ask whether it is time to move beyond the ‘kitchen-sink’ approach for postoperative pain management. They argue that truly personalised pain management requires perfect prediction: the ability to predict who, among a group of patients undergoing the same surgical intervention, will proceed to develop moderate-to-severe pain, who will specifically benefit from a more inclusive approach to selecting analgesic modalities and who will benefit from longer vs. shorter duration of initial postoperative pain treatment. 

There is growing interest in how artificial intelligence will affect our lives in the future, but can machine learning predict myocardial injury and death after cardiac surgery? This new secondary analysis of the VISION study from Nolde et al. finds that it can, and that most discriminatory information was provided by pre-operative patient characteristics, with discrimination increased by pre-operative investigations and peri-operative variables. Two editorials provide important context to work published earlier in the year. First, Shanthanna discussed risk factors and prediction modelling for chronic post-surgical pain after breast cancer surgery. Importantly, chronic post-surgical pain is an important health concern for nearly 64% of women having breast cancer surgery. It is crucial therefore to precisely define the outcome being measured and understand the associated complexity. Second, Wiles comments on a consensus statement that was endorsed by multiple specialty bodies on the use of CT as an ancillary investigation to support a diagnosis of death using neurological criteria. He argues it is an investigation that will be used more frequently and that the guideline will help maintain public and clinician confidence in diagnosing neurological death. Elsewhere we have reviews of renal medicine, liver care and haematological malignancies in ICU, and two brand new Reviewer Recommendations looking at survey-based research and engaging in social media. 

Finally, we hope to see you for Annual Congress this coming September in Edinburgh. Our highlights include seeing Dr Tanya Selak from New South Wales demystify sugammedex as well as Prof Mike Irwin talking all things TIVA. 

Mike Charlesworth and Andrew Klein

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