Pre-operative isolation – friend or foe?

This month, we are delighted to publish another fantastic study from the COVIDSurg and GlobalSurg collaboratives who were recently awarded a Guinness World Record for work previously published in the journalThis new paper comes from 15,025 global authors based in over 1600 hospitals and reports data for 96,454 patients. The topic this time is pre-operative isolation, which was introduced as a precaution despite limited evidence on its benefits and harms. It aims to keep systems clean and patients safe, but is it risk free? They found that, following correction for various measured confounders, it was associated with a small but clinically important increase in postoperative pulmonary complications (Fig 1). In the associated editorial, Charlesworth and Grossman set out how this new information may help us move towards ‘COVID-19 secure’ elective surgery. If indeed pre-operative isolation is not without risk, then hospitals need to focus on how this may be tackled as well as other ways in which nosocomial transmission can be prevented.

Figure 1 Multivariable logistic regression model exploring the association between pre-operative isolation and postoperative pulmonary complications, adjusting for patient, surgery and surgical setting factors. Number in dataframe = 96,454; number in model = 96,067; missing = 387; AIC = 16,680.6; C-statistic = 0.784. Full model presented in online Supporting Information Table S4, including an interaction term of isolation and country income. Community prevalence of SARS-CoV-2 was defined as the median 14-day cumulative country case notification rate per 100,000 population during October 2020. Country income groups defined as per the World Bank classification. 

One such area where there remains room for improvement is incorporating what we now know about ‘aerosol-generating procedures’ into policy documents, guidelines and local procedures. This new study from Wilson et al. yet again shows that therapies such as high flow nasal oxygen and continuous positive airway pressure generate less aerosol as comparted with breathing, talking, exercising, shouting or coughing. Such therapies should not therefore be delayed in patients with COVID-19 and we should instead focus on ‘aerosol-generating patients’, not procedures. Also featuring this month is a new Association of Anaesthetists guideline for regional analgesia for lower leg trauma and the risk of acute compartment syndrome. This guideline generated a lot of debate on social media and the associated podcast provides some useful context. Perhaps one of the main talking points was recommendation six, which stated that neither the surgeon nor the anaesthetist has the right to veto a treatment recommended by the other. The associated editorial from Bogod and McCombe expands upon the associated controversies including aspects of patient ownership and autonomy. They also discuss the reasons why the British Orthopaedic Association were unable to endorse the final document. The editorial from Keating and Duckworth focusses on clinical aspects of the guideline with particular emphasis on the need for more monitoring in acute compartment syndrome. Such monitoring has been available now for over three decades and perhaps enables patients to receive appropriate analgesia appropriate to the circumstances.

For patients who have suffered traumatic injuries, reducing time from injury to definitive care is perceived to be associated with improved health outcomes. This new retrospective analysis of linked registry data from Lyons et al. aimed to evaluate the effect of the introduction of the Emergency Medical Retrieval and Transfer Service (EMRTS) on 30-day mortality in patients who had suffered blunt traumatic injuries (Fig. 2). After adjustment for differences in case-mix, they found a 37% reduction in the adjusted OR for 30-day mortality in patients with blunt traumatic injuries who were treated by EMRTS compared with standard pre-hospital care pathways. Hurst and Lendrum remind us of the reasons why this was not a good comparison of ground vs. helicopter emergency medical systems, but there remain some important clinical messages. For example, there is a need to include all trauma patients in national registries and establish why injured patients die in the early post-injury phase.

Figure 2 Inclusion criteria and data cleaning for the study population. EMRTS, Emergency Medical Retrieval and Transfer Service; TARN, Trauma Audit and Research Network; ISS, injury severity score; GCS, Glasgow coma scale; PMC, pre-existing medical conditions.

Postoperative sleep disturbance is perhaps more common than we think with significant consequences for patients. Earplugs and eye masks are low-cost interventions that may help, yet this is an area which has received little attention in the peri-operative literature. Leong et al. report their randomised controlled trial of effect of the use of earplugs and eye masks on the quality of sleep after major abdominal surgery. They did not find that the use of earplugs and eye masks as sleep aids on postoperative days 1–3 improved the sleep quality of patients after major abdominal surgery, nor did it affect patient satisfaction, reduce the frequency of nursing care required or reduce the incidence of delirium. We look forward to receiving more original articles in this area and there is much to be done. 

Severe pain after total hip arthroplasty can have major negative effects on recovery and mobilisation in the postoperative period. Pascarella et al. report their randomised observer-masked controlled trial of the impact of the pericapsular nerve group (PENG) block on postoperative analgesia and functional recovery following total hip arthroplasty (Fig. 3). They found that the PENG block improved postoperative analgesia following total hip replacement, and decreased pain scores and opioid consumption during the first 48 h after surgery. Time to now consider it as a valid analgesia option for fast-track hip surgery protocols? Finally, Finnerty et al. report their randomised trial of bilateral erector spinae plane block vs. no block for thoracolumbar decompressive spinal surgery. They found that the addition of intra-operative erector spinae block to multimodal analgesia improved recovery and reduced pain up to 24 h after thoracolumbar decompressive spinal surgery. Perhaps another indication for a block that has exploded in popularity despite being discovered and reported for the first time only recently

Figure 3 PENG block via a lateromedial approach. Once the needle was placed in the plane between the iliopsoas tendon (IPT) and periosteum and between the anterior inferior iliac spine (AIIS) and iliopubic eminence (IPE), the PENG block was performed by injecting 20 ml of local anaesthetic, the spread of which is visible under the iliopsoas muscle (IPM). Arrow, needle pathway; blue dashed line, local anaesthetic spread; FA, femoral artery. Asterisk, needle entry point.

Elsewhere we have: a review of oxytocin at birth and beyondan observational study of temporomandibular joint dysfunction following the use of a supraglottic airway device during general anaesthesia; and a randomised controlled trial of the effect of saline versus air for cuff inflation on the incidence of high intra-cuff pressure in paediatric MicroCuff® tracheal tubes.

Make sure you check out our top 10 papers of 2020 which we announced only last week at an excellent Annual Congress virtual conference! Congratulations to El-Boghdadly and team for winning paper of the year which was all about risks to healthcare workers following tracheal intubation of patients with COVID‐19!

Mike Charlesworth and Andrew Klein

Delivering person-centred critical care

There has been concern for some time in some areas of the UK that critical care admission is rationed according to age. This new retrospective observational study from Pugh et al., which was conceived and conducted before the outbreak of COVID-19, aimed to investigate trends in patient characteristics for adult critical care admissions in Wales between 2008-2017. They analysed 85,629 cases with the oldest cohort (≥ 80 years) accounting for 15% of critical care admissions. The proportions in each age bracket did not change over the study period. However, in contrast to several recent reports, they identified a significant decline in admissions of older patients (aged ≥ 65 years) relative to the national population, of those with comorbidity and those with a medical diagnosis (Fig. 1).

Figure 1 Rates of ICU admission per 10,000 population over time by age group with 95%CIs.

Has critical care capacity failed to keep pace with the needs of an ageing population? Lone and Suntharalingam make a case for the need to learn, adapt and ensure equity and appropriate best care for our growing cohorts of those aged > 65 years and new octogenarians. That said, the priority for many older critically unwell adults is not always survival at all costs. What will anaesthesia and peri-operative medicine look like to us when many of the current workforce are classed as an older adult in ~25 years? Fawcett and Klein discuss the implications for genomics, AI, service delivery, peri-operative medicine, green anaesthesia and radiology. The only certainty seems to be that our skills will continue to be in demand and there will inevitably be significant workforce shortages. 

Dexmedetomidine is now used widely for several indications in peri-operative practice and critical care medicine. This new randomised controlled trial from van Norden et al. is the first to investigate the effect of peri-operative administration of dexmedetomidine on the incidence of postoperative delirium in major cardiac and non-cardiac surgical patients aged > 60 years. They found that found a significant reduction in postoperative delirium to 18% from 44% when dexmedetomidine was administered as compared with placebo (Fig. 2). In the accompanying editorial from Chuan and Sanders, the biological plausibility of this finding is assessed, and dexmedetomidine might not be the much sought-after magic bullet for the prevention of postoperative.

Figure 2 Cumulative case count of delirium in dexmedetomidine (red) and placebo (blue) groups.

This new science letter from Shah et al. reports results from a retrospective cohort study of general ICU survivors in two large health regions in the UK aiming to benchmark how many patients had anaemia-specific treatment (excluding blood transfusion) initiated before hospital discharge. The key findings were: a high prevalence of anaemia at ICU discharge and subsequently hospital discharge; little active management of anaemia during this important time period; and Hb of < 100 g.l-1 was associated with prolonged hospitalisation following ICU discharge. Also in this month’s issue, van der Laan et al. report their retrospective analysis of anaemia among intensive care unit survivors and its association with days alive and at home. They found that among ICU survivors, anaemia was highly prevalent and persistent in most patients at hospital discharge. Haemoglobin concentration < 100 g.l-1 at ICU discharge was experienced by 2886 (45.4%) of ICU survivors and independently associated with five fewer days alive and at home to day 90. This association remained significant when accounting for confounders including ICU length of stay, illness severity and red blood cell transfusion, and was attributable predominantly to fewer days at home among anaemic ICU survivors. In addition, ICU discharge anaemia was also an independent predictor of ICU and hospital re-admission (Fig. 3). In the accompanying editorial, Agarwal and Karkouti discuss both studies and remind us that the findings from each might at best be hypothesis generating only. They remind us of the vast amount of work still to be done in what is becoming and increasingly important area of clinical practice.

Figure 3 Association between haemoglobin at ICU discharge and DAH90 by ICU length of stay.

We are delighted to publish a Special Article from Takla et al. in this month’s issue, which raises some difficult ethical and legal issues around the use of general anaesthesia in end-of-life care. They remind us that our speciality already has a self-declared mission to extend the role of anaesthetists beyond the operating theatre in its strategy of championing ‘peri-operative medicine’. They argue that their redefinition of the scope and reach of general anaesthesia through end-of-life care, radical though it is, would be entirely in line with that philosophy, recognising that anaesthetists have skills that can help alleviate suffering for the dying patient. Their main findings were that peri-operative lidocaine infusions of extended duration can be delivered safely and effectively in patients undergoing breast cancer surgery, and that a definitive, multicentre trial employing these design features is feasible. 

One of our most popular podcasts episodes was about the use of intravenous lidocaine in peri-operative practice released November 2020This new pilot multicentre randomised controlled trial of lidocaine infusion in women undergoing breast cancer surgery from Toner et al. enrolled 150 patients and looked at safety, effectiveness and the feasibility of a larger trial. Daliya et al. report their retrospective observational study of Opioid prescription at postoperative discharge. They were able to isolate a number of recognised risk-factors in the prescribing habits of clinicians at discharge that could contribute to a large unused pool of opioids in the community. In the accompanying editorial, Albrecht and Brummett remind us that if you cannot measure it, you cannot improve it. They argue that improvement can be made through: proper adherence to education and guidelines; by embracing simple measures such as prescription of non-opioid analgesics at regular intervals; specification on the duration of the course of immediate-release opioid tablets; avoidance of long-acting opioid formulations and compound analgesic preparations; and advice on deprescribing.

Elsewhere this month we have: a systematic review of suicide in anaesthetistsa systematic review of simulation-based team training in airway managementnew Association of Anaesthetists fire safety and evacuation guidelines; and a time-sensitivity analysis of the prognostic utility of vasopressor dose in septic shock

Finally, make sure you do not miss our next live broadcast with our Associate Editor Dr Tanya Selak chairing which is all about a new paper on the safety of day-case paediatric tonsillectomy in England from the Getting It Right First Time programme. You can tune in by coming to @Anaes_Journal (or following this link) at 1200 BST on Friday 17th September!

See you then!

Mike Charlesworth and Andrew Klein

Staff are our most valuable asset

In the UK, COVID-19 continues to impact upon the provision of all NHS services. This new serial service evaluation from Kursumovic et al. was able to measure and report on the impact on anaesthesia and critical care services in the UK between October 2020 and January 2021. Interestingly, this study made use of the NAP6 infrastructure, as the project was on hold during the pandemic. During this time, one in eight anaesthetic staff were not available for work and one in five operating theatres were closed, with activity falling significantly in those theatres that were open. During January 2021, the system was largely overwhelmed. Redeployed anaesthesia staff increased the critical care workforce by 125% and three quarters of critical care units were expanded. This all helps us to work out what happened which will hopefully mean we are better placed to respond to future pandemics. 

The survey focusses on three key factors – staff, space and stuff. In the accompanying editorial, Wong et al. argue that staff are our most valuable asset. We have all and will continue to work in new ways because of the pandemic, and there has been much focus on ways in which to combat the effects of workforce burnout. It nevertheless remains to be seen whether recommendations such as better provision of mental health support, improved pay, combating workplace bullying and delivering better workforce planning will be implemented. The arguments provided by Wong et al. are compelling and their thoughts seemed to resonate with our followers over on Twitter. For this workforce will also be the one that looks after our nation’s health for years to come. 

There have been numerous observational studies reporting on outcomes in patients with COVID-19 admitted to intensive care. This new systematic review and meta-analysis from Taylor et al. finds that increasing age, pre-existing comorbidities and greater severity of illness are associated with mortality in patients admitted to ICU with COVID-19, but male sex and increasing BMI were not. This surprising finding attracted a lot of attention on social media and with nine news outlets also featuring the study. In the associated editorial from Cook and Comporota, state the case for core datasets for critical care outcomes from COVID-19. These will not only be of benefit for this and other pandemics, but also for the major health challenges that affect ICUs across the world. 

How best to pre-oxygenate patients prior to rapid sequence intubation (RSI) continues to be debated. This new randomised controlled trial from Sjöblom aimed to compare high-flow nasal oxygen with tight-fitting facemask pre-oxygenation during RSI in patients undergoing emergency surgery in several different centres. They showed no difference in the number of patients desaturating < 93% between pre-oxygenation using high-flow nasal oxygen vs. tight facemask. Lam and Irwin ask, is high-flow nasal oxygen worth the hassle? It does seem to be safe, but it is more expensive, time-consuming, technically more difficult to prepare does not appear to have any major benefits over other accepted techniques. We need more research in specific patient groups such as obese, pregnant and high-risk patients more generally. Also this month, Sud et al. compare gastric gas volumes measured by computed tomography between high-flow nasal oxygen therapy and conventional facemask ventilation. They find that high-flow nasal oxygen does not increase gastric gas volume in fasted patients undergoing induction of anaesthesia in the supine position, which adds further support to the safety of its use. 

Figure 1 Oxygenation until 1 min after intubation. Lowest SpO2 (%) from start of pre-oxygenation until 1 min after intubation and apnoea time (s) is plotted for every patient pre-oxygenated with high-flow nasal oxygen (n = 174) or facemask (n = 175). High-flow nasal oxygen (red squares); facemask (blue dots). Desaturation was defined as SpO2 < 93% (dotted line). *No intubation time was noted. Therefore, this patient had the mean intubation time in the high-flow nasal oxygen group added to its apnoea time up until the laryngoscope passed the teeth.

Every year, > 130k patients survive an episode of critical illness in the UK. Focus on this patient group will no doubt increase as the pandemic hopefully eases. This new mixed-methods systematic review from Bench et al. finds that fatigue is common in critical illness survivors, with a prevalence ranging from 13.8–80.9%. This rises around one month following ICU discharge and improves over time but seldom resolves completely. There is a paucity of evidence on how best it should be detected or managed. In the accompanying editorial, Hosey et al. argue that we must help ICU survivors find new ways to live with chronic symptoms, with clinicians and researchers striving to design and evaluate multidisciplinary and comprehensive treatment modalities that support recovery from the ICU to home. 

Figure 2 SF-36 vitality scores over time for data from (a) observational cohort studies and (b) randomised controlled trials. Values are mean (95%CI).

The new Association of Anaesthetists 2021 recommendations for standards of monitoring during anaesthesia and recovery have now been cited 7 times and attracts an Altmetric score of > 250. Areas of controversy include new guidance on: capnography; transfer; quantitative neuromuscular monitoring; processed electroencephalogram monitoring; and electronic record keeping. They feature in this month’s issue, and they are essential reading for all. Elsewhere we have: a randomised controlled trial of deep serratus anterior plane block vs. sham block in ambulatory breast cancer surgerya narrative review of adjunctive treatments for the management of septic shocka systematic review of the association between intra-operative cardiac arrest and country Human Development Index statusan evaluation of group teaching before surgery (Fit-4-Surgery School); and a feasibility and pilot study of volatile anaesthesia and peri-operative outcomes related to cancer

Many of this month’s articles have an associated podcast which you can listen to here. It also features the most recent podcast which looks at the new COVIDSurg international prospective cohort study on the effects of pre-operative isolation on postoperative pulmonary complication rates. The paper remains free to access forever!

Mike Charlesworth and Andrew Klein

Dexamethasone for all?

Dexamethasone is a drug that has many uses for a range of indications and patient groups. This month, the results of the STRIDE randomised controlled feasibility trial are reported. Kluger et al. recruited 79 participants with hip fracture undergoing surgery and randomised to dexamethasone 20 mg or placebo. They found a number of factors that will help design and complete a larger definitive study. Although delirium was less severe in the dexamethasone group, there was no difference in terms of its incidence. We look forward to a larger definitive trial in the future which is evidently scientifically valid and feasible. In the accompanying editorial, Abraham and Neuman dissect the STRIDE study and draw their own conclusions. They highlight the need for future trials to consider the possible risks associated with steroids, such as postoperative infections. The important point is that this is an area that has not been well studied, and this trial means that trialists working in this area will be better equipped to provide the definitive evidence that we need.

The PROSPECT papers always receive a lot of attention on social media which is probably due to their pragmatic methods and clinically relevant suggestions. This new contribution is aimed at patients undergoing total hip arthroplasty with seven core evidence-based recommendations. The key difference here is that most other guidelines focus on enhanced recovery or anaesthetic technique rather than the best analgesic regimen. In the accompanying editorial, Abdallah and McCartney list what’s old, what’s new and what continues to be missing. Will new iterations include items such as day case surgery, the approach to patients with chronic pain, second- or third-line strategies and novel blocks, not in widespread use at the time of this literature search? Time will tell.

During the first COVID-19 wave in the UK, the general anaesthesia rate for caesarean sections in the north-west decreased significantlyThis new study analyses the impact of increased regional anaesthesia use during the pandemic on the decision-to-delivery interval and neonatal outcomes for category-1 caesarean sections. They conclude that the there was a small, clinically unimportant increase in decision-to-delivery interval for category-1 caesarean section during the first wave of the COVID-19 pandemic (Fig. 1). This arguably supports the safe use of regional anaesthesia for category-1 caesarean section except in those cases which warrant the most urgent delivery. Just what then is a clinically significant decision-delivery interval? Mike Kinsella sets out the evidence, the problem with general anaesthesia and considerations for rapid achievement of delivery under general anaesthesia for category-1 caesarean section with fetal compromise. He argues that 30 min, embedded in audit and clinical practice though it is, is too long for cases where there is fetal compromise. He calls for a new 20min target which should be seen as a new clinically-relevant standard. Do you agree? Let us know!

Figure 1 The significant dependency of general anaesthesia (GA) on indication ordered by neonatal morbidity is shown using non-parametric regression (median slope: 1.03% (95%CI 0.09–1.86), Spearman’s rho correlation 0.81, p = 0.022). Chi-square trend analysis shows a significant 5.6% (95%CI 4.2–7.0); p < 0.0001) change in general anaesthesia rate per ordered indication category. There is a significant use of general anaesthesia for the top four indications combined with adverse neonatal outcomes (odds ratio 3.5 (95%CI 2.2–5.4); p < 0.0001). APH, antepartum haemorrhage; CTG, cardiotocography.

The 7th UK National Audit Project has now begun, and the aim will be to advance our knowledge and understanding of peri-operative cardiac arrests. This new article from Kane et al. lists the challenges faced, such as defining peri-operative cardiac arrest, determining the scope of study and conducting the project in the era of COVID-19. You can hear all about the issues raised in the editorial and much more by listening to the podcast, which is free! One area that has been studied extensively is myocardial injury following non-cardiac surgery and the influence of remote ischaemic preconditioning (RIPC). This new 1-year follow-up from a randomised controlled trial from Ekeloef et al. finds that RIPC did not reduce the occurrence of major adverse cardiovascular events within 1 year of hip fracture surgery (Fig. 2). Looking at individual components of the primary outcome, the preventive effect of RIPC on myocardial infarction seems to hold for 1 year. 

Figure 2 Effect of remote ischaemic preconditioning on 1-year clinical outcomes expressed as hazard ratios. Error bars indicate 95%CIs. MACE, major adverse cardiac event.

This new paper from Maranhao et al. has been available on early view since late 2020 and has attracted a lot of attention on social media. They undertook a systematic review and network meta-analysis to compare spinal needles and their respective odds of post dural puncture headache. They find that the 26-G atraumatic spinal needle is the most likely needle to enable successful insertion while avoiding PDPH. Where this needle is not available, as seems to be the case in most institutions according to Twitter, they provide a rank order to help clinicians select the best among the available options. Whether an intrathecal catheter for labour analgesia reduces the incidence of post-dural puncture headache or need for an epidural blood patch has been questioned. Orbach-Zinger et al. report their literature review and clinical management recommendations for intrathecal catheter use after accidental dural puncture in obstetric patients. Although such a catheter might provide effective and satisfactory labour analgesia, there are several important complications that usually negate their use. Eight clear recommendations are provided.

Elsewhere we have: a description of the new Anaesthesia Case Report (ACRE) checklista prospective study of persistent headache and low back pain following accidental dural puncture in the obstetric populationa retrospective study of labour epidural case volume and the rate of accidental dural puncture; and a narrative review of routinely collected data and patient-centred research in anaesthesia and peri-operative care

Last but by no means least is the penultimate Contemporary Classic article in the series which tackles the 2010s. Kumar et al. have picked a paper from Blanco et al. from 2013 which was the first to describe the serratus plane block. They discuss the identification of new potential sono-anatomic targets, undertaking exploratory studies and translating this pioneering research into clinical practice. They argue the work from Blanco et al. is a classic because it taught us important lessons about how to introduce a novel and potentially useful fascial plane block into clinical practice. It also greatly influenced the expansion in ultrasound-guided block techniques, which increases the likelihood that all surgical patients may one day have access to regional anaesthesia as part of their peri-operative pain management.

Congratulations to our new trainee fellow, Dr Cara Hughes! Cara is a clinical research fellow based at the Academic Unit of Anaesthesia at the University of Glasgow. We look forward to welcoming her to the team!

Mike Charlesworth and Andrew Klein

Charting the way forward

COVID-19 has had a tremendous impact on access to healthcare services, including anaesthesia and surgery. What is the best way to proceed for those patients who have been infected with SARS-CoV-2? In this issue of AnaesthesiaEl-Boghdadly et al. outline key principles in the timing of surgery after SARS-CoV-2 infection in a multidisciplinary consensus statement supported by the Association of Anaesthetists, the Centre for Peri-operative Care, the Federation of Surgical Specialty Associations, the Royal College of Anaesthetists and the Royal College of Surgeons of England. Specific focus is afforded to symptoms and severity of disease, comorbid and functional status, priority and complexity of surgery, and anaesthetic technique. The consensus statement is informed by recent studies, such as the international prospective cohort study of the COVIDSurg and GlobalSurg Collaboratives, which was published in Anaesthesia, and which quantified mortality risk in patients with pre-operative SARS-CoV-2 infection based on the time interval between diagnosis and surgery. An accompanying editorial by Price et al. addresses the curtailment in surgical activity caused by the pandemic and its effects on the workforce, both in terms of reallocation of duties and psychological consequences. A further editorial by Stuart White asks whether a role exists for mandatory psychological assessment of those working in anaesthesia and critical care medicine during the pandemic. The impact of this pandemic on patients, healthcare workers and broader society will extend long beyond its end. 

Even in a world without COVID-19, access to safe and affordable surgical care in low- and middle-income countries can be erratic. Reliable data is essential for the evaluation and advancement of peri-operative care in these regions. In this issue, the Network for Peri-operative Critical Care reports on the establishment and initial output of an Ethiopian data registry that incorporated national surgery and quality indicators. There were 1748 care episodes in four hospitals recorded in the registry over a 12-month period, including data on anaesthetic adverse events and post-operative morbidity and mortality. In an accompanying editorial, Kluyts and Biccard discuss the role of peri-operative registries in improving the quality of care in low-resource environments and the challenges associated with their creation and interpretation.

The prevention and treatment of postoperative nausea and vomiting is one of the commonest everyday challenges faced by anaesthetists. Weibel et al. publish an abridged Cochrane network meta-analysis of the drugs used for preventing post-operative nausea and vomiting in adults after general anaesthesia (Fig. 1). Data are included from 585 trials and 97,516 participants, evaluating 44 single drugs and 51 drug combinations, making this the most comprehensive, up to date review of the evidence in this area. An accompanying editorial by Collier and Smith places these findings in the context of current anaesthesia practices and the broader challenges faced in preventing post-operative nausea and vomiting

Figure 1 Network geometry of eligible comparisons for postoperative vomiting within 24 h after surgery. The thickness of the edges is proportional to the number of included studies comparing two treatments.

As researchers continue to investigate the exact risks and benefits of apnoeic oxygenation with high-flow nasal oxygen in anaesthesia, areas of uncertainty include its merits in the paediatric population and capacity for clearance of carbon dioxide. The ability of apnoeic oxygenation with high-flow nasal oxygen to clear carbon dioxide in adults was first postulated by Patel and Nouraei in this journal in 2014. This phenomenon has not been demonstrated in paediatric patients. In this issue, Riva et al. publish their transcutaneous evaluation of carbon dioxide elevations in apnoeic children weighing 10-15 kg by comparing two oxygen flow rates.  

Regional anaesthesia also features in this issue – from assessment of the needle manipulation of novices to the role of adjunctive agents in brachial plexus blockade. Chuan et al. report the results of their randomised controlled trial examining the potential role for visuospatial ability screening in learning ultrasound-guided regional techniques. The visuospatial ability of anaesthetists, as measured by their ability to identify similar three-dimensional objects from different perspectives, was hypothesised to correlate with their ability to perform ultrasound-guided needle manipulation, which is an essential component of regional anaesthesia performance. The needling times of 140 medical students during ultrasound-guided tasks are reported, after randomisation by visuospatial ability, with some participants receiving deliberate practice and others assigned to discovery learning. Meanwhile, Sehmbi et al. report their meta-analysis of 100 trials on supraclavicular brachial plexus block characteristics when dexamethasone and dexmedetomidine are administered as adjunctive agents. The authors evaluated the effects of these agents on sensory block, motor block and analgesic duration by comparing with control supraclavicular blocks that were performed without adjuncts. The route of administration of the agents (perineural or intravenous) was incorporated into their analysis.

The bleeding post-cardiac surgery patient is both a unique haematological challenge and a commonly faced problem in cardiac intensive care units. How best to identify and manage specific deficits in coagulation, and measure the response, remains a matter of ongoing debate. This issue features a pilot randomised controlled trial comparing the use of prothrombin complex concentrate and fresh frozen plasma in adult patients who required coagulation factor replacement for bleeding within 24-hours of cardiac surgery. Elsewhere, Kataife et al. evaluate the impact of the Haemostasis Traffic Light cognitive aid on clinician performance during simulated bleeding scenarios (Fig. 2).

Figure 2 Design of the Haemostasis Traffic Light. The five steps are described (0 to 4) from left to right. Each step has its rationale and an example of an intervention (dotted line) to show how the Haemostasis Traffic Light concept may be adapted to institutional coagulation management protocols.

The dose of oxytocin administered during elective caesarean delivery has reduced over the last two decades. In this issue, Peska et al. report the results of an oxytocin dose-finding study in obese women at elective caesarean delivery, using the biased coin up-down method. The primary outcome was uterine tone as assessed by the operating obstetrician two minutes after drug administration.

Finally, in this month’s Contemporary Classics series, revisiting some notable papers that have featured in Anaesthesia in celebration of its 75th anniversary, Tim Cook, Ellen O’Sullivan and Fiona Kelly discuss the origins and impact of the 2004 Difficult Airway Society guidelines for the management of difficult tracheal intubation. To round off this issue, our popular Correspondence section has its reliable mixture of personal observations and insights along with commentary and debate surrounding recently published research in Anaesthesia.

We hope you enjoy the diverse range of topics featured in this month’s issue. Stay tuned to our twitter feed for daily updates on the journal’s articles, podcasts and live broadcasts!

Craig Lyons and Andrew Klein

Data, answers and questions

This month, we are delighted to publish a new international prospective cohort study from the COVIDSurg and GlobalSURG collaboratives. It is now our best performing paper on social media, ever, with an Altmetric score of > 2400! They studied > 140k patients in 116 countries and concluded that the risks of postoperative morbidity and mortality are greatest if patients are operated within 6 weeks of diagnosis of SARS-CoV-2 infection (Fig. 1). Their work highlights how collaboration on an international stage such as this can give us the answers we need to clinically important questions that matter to hospitals, clinicians and patients. Their work has helped formulate new guidelines which have been implemented across the UK. In the accompanying editorial, Wijeysundera and Khadaroo take us through the complexity of asking when the safest time to operate on a patient with prior SARS-CoV-2 infection is. They highlight the need for quality standards specifically tailored for these large multicentre collaborative studies. Provided that the research question, study design and team are strong and efficient, collaborative research is to be commended and must be continued.

Figure 1 Overall adjusted 30‐day postoperative mortality from main analysis and sensitivity analyses for patients having elective surgery and those patients with a reverse transcription polymerase chain reaction (RT‐PCR) nasopharyngeal swab positive result for SARS‐CoV‐2. ‘No pre‐operative SARS‐CoV‐2’ refers to patients without a diagnosis of SARS‐CoV‐2 infection. The time‐periods relate to the timing of surgery following the diagnosis of SARS‐CoV‐2 infection. Sensitivity analysis for RT‐PCR nasopharyngeal swab proven SARS‐CoV‐2 includes patients who either had RT‐PCR nasopharyngeal swab proven SARS‐CoV‐2 or did not have a SARS‐CoV‐2 diagnosis; patients with a SARS‐CoV‐2 diagnosis which was not supported by a RT‐PCR nasopharyngeal swab were not analysed. 

We have several high-quality obstetric anaesthesia papers this month, as well as a podcast. First, Odor et al. present the findings from their multicentre prospective cohort study – the direct reporting of awareness in maternity patients (DREAMY). Their main finding was that the incidence of accidental awareness during general anaesthesia (AAGA) in obstetrics, assessed by using direct questioning, is almost three times higher than previously ascertained when relying on patient self‐reports: 1 in 256 (95%CI 149–500) vs. 1 in 1200 (95%CI 714–2500). There are many other nuggets of information here of relevance to all anaesthetists, and the paper has reignited the debate about choice of anaesthetic agents for obstetric general anaesthesia as well as a range of other topics. In the accompanying editorial, Palanisamy and Paech discuss these practice changes, the associated controversies and the possible consequences of the work by Odor et al. They argue the most significant contribution is the association between AAGA and post-traumatic stress disorder, the incidence of which is broadly in keeping with previous reports in other patient populations. Therefore, early recognition of AAGA and subsequent intervention is more important now than ever.

Figure 2 Study flowchart of participant recruitment and outcome adjudications. Outcomes are stratified as accidental awareness during general anaesthesia (AAGA) and ‘No AAGA’, with ‘Unlikely AAGA’ included in the latter category. A total of six patients had screening Brice interview responses indicating suspected awareness during general anaesthesia; however, verification assessment was not able to be completed, hence insufficient evidence was available to adjudicate these reports using equivalent criteria to the remaining cases.

Second, this new randomised controlled trial from Chapron et al. finds that spinal anaesthesia with hyperbaric prilocaine induced a shorter and more reliable motor block compared with bupivacaine, administered in spinal anaesthesia for non‐breastfeeding women with uncomplicated pregnancies and undergoing elective caesarean section. The suggestion that prilocaine might be more useful than bupivacaine in this setting is sure to cause, at the very least, some raised eyebrows in the obstetric anaesthetic community. Carvalho and Sultan provide their analysis and conclude that if hyperbaric prilocaine is ever contemplated for routine use, it should be used in conjunction with a combined spinal‐epidural technique. This is so that if the surgical duration exceeded the duration of spinal anaesthesia, the epidural could be dosed to maintain anaesthesia and reduce the need for conversion to general anaesthesia. Third, Heesen et al. discuss the use of noradrenaline as compared with phenylephrine in women undergoing spinal anaesthesia for caesarean section. They highlight that the effect of noradrenaline on fetal acidosis is still unclear, but in the best case scenario it is no worse than phenylephrine. Some excellent suggestions are provided for those undertaking studies in this area. 

Sickle cell disease is one of the most common serious inherited single gene disorders worldwide and has a major impact on the health and life expectancy of the individual. These new Association of Anaesthetists guidelines were developed to highlight advances in peri‐operative care of patients with sickle cell disease, provide anaesthetists with a better understanding of sickle cell disease and to make recommendations about the organisation of care for this complex group of patients. Twelve key recommendations are provided, which are included in the infographic below. 

Elsewhere we have: a systematic review and meta-analysis of conventional landmark vs. preprocedural ultrasound for neuraxial analgesia and anaesthesia in obstetricsa systematic review of reporting quality for anaesthetic interventions in randomised controlled trialsa systematic review of melatonin for anaesthetic indications in paediatric patientsa pilot and feasibility study of postoperative wrist worn accelerometers; and an observational study of exploring the limits of prolonged apnoea with high-flow nasal oxygen

Finally, this new paper from Matt Wiles has been extremely popular on social media. He was tasked with taking on a classic paper from the 1990s and chose an article by Nolan and Wilson about tracheal intubation in patients with spinal injuries. Is manual in-line stabilisation (MILS) during tracheal intubation effective protection or harmful dogma? He presents a persuasive argument against, and urges clinicians to reflect on why they continue to choose to use MILS during tracheal intubation – is this for patient benefit, for protection against later criticism or medicolegal claims, or because ‘we have always done it this way’? Do you disagree? Send us your thoughts in a letter! We might just publish it and get Matt to respond.

Do you want to be our next journal fellow? The deadline for our next post is approaching, so make sure you start working on your application now. Previous fellows include Helen Laycock, Mike Charlesworth and Kariem El-Boghdadly, who are now all fully fledged Editors!

Mike Charlesworth and Andrew Klein

Old problems and new realities

Between the application of artificial intelligence to regional anaesthesia, the use of virtual reality in pain management and a modern interpretation of the iron lung for respiratory failure, the May issue of Anaesthesia examines some modern solutions to longstanding challenges.

Bowness, El-Boghdadly and Burckett-St Laurent discuss the role artificial intelligence for image interpretation in ultrasound-guided regional anaesthesia. The identification of anatomy under ultrasound is an essential step in the performance of regional blockade. Challenges with anatomical recognition and needle guidance limit the number of clinicians willing to learn or perform regional techniques. Might artificial intelligence become reliable to the point of recognising and highlighting different anatomical structures, whilst accounting for patient anatomical differences and proceduralist variability in image acquisition? Additionally, could this technology propose optimal needle trajectories to reduce the likelihood of nerve injury or intravascular injection of local anaesthetic?

Figure 1 Sono-anatomy of the adductor canal block. (a) Illustration showing a cross-section of the mid-thigh. (b) Enlarged illustration of the structures seen on ultrasound during performance adductor canal block. (c) Ultrasound view during adductor canal block. (d) Ultrasound view labelled by AnatomyGuide.

The application of virtual reality as a non-pharmacological pain therapy is reviewed by Chuan et al. in this issue. They discuss its potential role in acute and chronic pain scenarios, addressing the impact of their varied aetiological and biopsychosocial components on the efficacy of these programmes. In an accompanying editorial, Small and Laycock examine the broader application of virtual reality systems within healthcare along with the complexities involved in their evaluation in clinical trials

The familiarity of many clinicians with the ‘iron lung’ relates solely to their readings on polio epidemics. Improvements in positive-pressure ventilation technology in the mid-20th century resulted in a decline in the use of negative-pressure ventilation. But could the positive be turned into a negative once more with a comeback for the iron lung? This issue of the journal publishes an evaluation of the Exovent, a torso-only negative-pressure ventilatory support system, in volunteers. The device aims to generate continuous negative extra-thoracic pressure in order to increase functional residual capacity and avoid patient-ventilator dyssynchrony. The risk-benefit profile of the Exovent in clinical practice remains unknown at this time. 

Figure 2 Volunteer being ventilated in the Exovent in the semi‐recumbent position.

A new PROSPECT guideline on post-operative pain management for elective caesarean section features in the May issue of Anaesthesia. The guideline is based on analysis of 145 studies and addresses systemic non-opioid and opioid analgesics, neuraxial adjuvants, local and regional techniques, and surgical interventions. In an accompanying editorial, Landau and Richebé discuss procedure-specific and patient-specific approaches to pain management. They highlight procedure-related variations in caesarean delivery, such as parity, plurality and prior history. Patient-specific circumstances, such as substance abuse, mental health issues and patient expectations, also influence pain outcomes. The authors therefore advise caution against the indiscriminate application of such guidelines and encourage more comprehensive algorithmic approaches to address individual needs. 

Recent studies on peri-operative iron supplementation have raised as many questions as answers on this practice. This journal issue features two original research articles on the pre-operative use of intravenous iron in anaemic patients undergoing cardiac surgery. Both studies (one retrospective and one prospective observational) examine the impact of this intervention on haemoglobin level, transfusion rate and other complications. Meanwhile, Wittenmeier et al report the results of their prospective study on the detection of pre-operative anaemia in elective surgical patients using non-invasive haemoglobin measurement. The authors address the potential implications of these devices during pre-operative anaesthetic evaluation along with their limitations in determining when to administer a blood transfusion.

Meta-analyses and trial sequential analyses are only as good as their component trials enable them to be – working back to the methodological robustness of each study and individual patient enrolment. In this issue, an editorial by Kirkham and Taljaard discusses the role of trial sequential analysis in enabling us to draw firmer conclusions on existing literature and project future research needs. They use a recent meta-analysis and trial sequential analysis by Desai et al. on the role of epidural vs transverse abdominis plane block for abdominal surgery as a backdrop for their discussion. Ultimately, the conclusion of a meta-analysis traces its way back into the hands of every researcher involved in the included studies, each generating the bigger picture one paint stroke at a time.  

COVID-related research continues to feature prominently in Anaesthesia. Cook and Roberts model the impact of vaccination by priority group on UK deaths, hospital admissions and intensive care admissions from this illness. Meanwhile, Clinkard et al. evaluate the filtration efficacy of N95 respirators and modified snorkel masks in healthcare workers.

Chronic obstructive pulmonary disease is a co-morbidity frequently encountered by anaesthetists and an independent risk factor for peri-operative morbidity and mortality. In this issue, a review by Lee et al. provides advice on pre-operative optimisation of patients with this condition. Specific focus is afforded to pulmonary rehabilitation, smoking cessation, symptom and pharmacological optimization, nutrition and lung volume reduction procedures. The authors also discuss unmet research needs in this area and the potential role for a peri-operative disease pathway for the delivery of holistic care to patients with this potentially debilitating condition. 

In our Contemporary Classics series, commemorating 75 years of AnaesthesiaPearce, Duggan and El-Boghdadly ask whether Cormac and Lehane grading has stood the test of time. They examine the origins of this classification system, its subsequent modifications, and its role going forward, particularly as use of videolaryngoscopy increases.

Figure 3 Views obtained at laryngoscopy, assuming correct technique, as described by Cormack and Lehane [1]. (a) Grade-1 view; (b) grade-2 view; (c) grade-3 view; and (d) grade-4 view.

And… hot off the press! The May issue of Anaesthesia contains the malignant hyperthermia 2020 guideline from the Association of Anaesthetists. There have been a number of developments in the diagnosis and management of malignant hyperthermia since the last iteration of this guideline was published in 2011. Guidance is provided for anaesthetists beyond the acute period of the reaction, including critical care management, patient and family counselling, and referral for investigation. Patient populations at increased risk of developing malignant hyperthermia under anaesthesia are also discussed. You can listen to the podcast with Professor Phil Hopkins and patient, Connor Phillips, here!

All this, plus our popular correspondence section, is now available in the May issue of Anaesthesia. Please keep an eye on the journal’s twitter feed for live broadcasts, podcast releases and social media discussion surrounding our latest journal articles!

Craig Lyons and Andrew Klein 

Zombies circulate among us

Detecting false data presents reviewers, editors, journals, publishers and readers with many problems. Manuscripts alone, which are submitted to journals for peer review and consideration for publication, are seldom enough to make an informed judgment on the truth of included data. In this new study, John Carlisle reports his analysis of 153 randomised controlled trials submitted to Anaesthesia for which he requested authors supply individual patient data spreadsheets (Fig. 1). He detected false data in almost half of these spreadsheets, which likely translates to around a quarter of all randomised controlled trials submitted to the journal. He concludes that journals and editors should ask more questions about data on which submitted trials are based, rather than relying on summary statistics alone, which may not contain vital clues about data trustworthiness. In the accompanying editorial, Ioannidis looks at the nature and scale of the problem, as well as what can be done. The solutions are far from perfect, but include: more widespread use of individual patient data spreadsheets during review processes; a new focus on methods to interrogate other designs, such as observational studies; incorporation of the likelihood of false data into the design of systematic reviews; and promotion of transparency by funders and regulators. 

Figure 1 The cumulative submission of 526 randomised controlled trials (black line), in 73 (14%) of which Carlisle identified false data (solid red line) and in turn 43 (8%) he categorised ‘zombie’ (dashed red line). The rates Carlisle identified false data and categorised trials zombie increased after March 2019, when Anaesthesia adopted a policy of routinely requesting individual patient data spreadsheets from countries that submitted the most trials.

We have a number of important papers this month that each have an associated podcast, which can be accessed for free on PodbeanSpotify and iTunes. First, Odor et al. report the results from DREAMY in relation to general anaesthetic and airway management practice for obstetric surgery in England. They find that propofol and, to a lesser extent, rocuronium are now being used more frequently. The associated editorial from Wilson and Wrench suggests the UK is currently lagging the adoption of change, rather than leading it. Cook and Farrar, in our second most popular paper on social media, ever, discuss everything to do with COVID-19 vaccines, including the many implications for peri-operative practice as well as other wider issues for society (Fig. 2).

Figure 2 The access to COVID‐19 tools (ACT)‐accelerator is a collaboration whose stakeholders aim to speed up development, production and access to novel agents that are central to the response to COVID‐19, including diagnostics, therapeutics and vaccines. Stakeholders include organisations and individuals from the public, industry, commerce, academia and politics. Synergistic cooperation should mean its efficacy is greater than the sum of its parts. From‐accelerator with permission from ACT‐accelerator.

We were also delighted to publish this new consensus statement on the prevention of opioid-related harm in adult surgical patients by Levy et al. The document allows for all healthcare professionals to be aware of the risks and benefits of peri-operative opioid use, which will hopefully lead to better informed patients.

In 2008, it was predicted that there would be no publications in relation to peri-operative practice from UK authors by the year 2020. This new analysis from Ratnayake et al. provides and updated perspective, with ~124 papers per year published by UK groups in indexed journals. A worrying feature is the predominance of secondary research (for example, reviews) as compared with primary research (for example, clinical trials). Overall, the trend identified by Feneck et al. in 2008 seems to have been halted but not yet reversed. Paul Myles offers some insights and reminds us that the studies by Feneck et al. and Ratanayake et al. provide a UK-centric view, and that most peri-operative medicine journals across the world have improved in quality over the last ten years. Moreover, there are now more many more studies in high-impact general medical journals led or contributed to by UK anaesthetists, which is great progress. Yeung and Shelton argue that academic anaesthesia does not belong to the elite, as it belongs to us all. Perhaps where the real work is needed is advocacy, to encourage recognition of how and why research is fundamental to high-quality patient care. 

Each month, we are taking a look back through our archives at important papers from each decade, since the first issue of the journal was published 75 years ago. This month, Laycock and Harrop-Griffiths tackle the assessment of pain with reference to a key paper from 1976 by Revill et al. Note that the ‘assessment’ of pain and not its measurement is discussed, the importance of which is thoughtfully discussed. They argue that what perhaps is even more important than the assessment or measurement of pain is how we respond to its occurrence. 

Elsewhere we have: a systematic review of intra-articular infiltration analgesia for arthroscopic surgery; two prospective observational studies of alternative devices for postoperative patient temperature measurement;an ethnographic study of decision-making around admission to intensive care; and a feasibility study of the effect of advanced recovery room care on postoperative outcomes in moderate-risk surgical patients

Finally, we are looking for new Assistant Editors (deadline March 31st) and a new Trainee Fellow (deadline May 31st). Both adverts and all the details are provided here, on the journal webpage, on Twitter, in this month’s Anaesthesia News and via the Association of Anaesthetists. Join us!

Mike Charlesworth and Andrew Klein

In need of a distraction?

The phone rings. The pager bleeps. A colleague drops into the theatre to talk. Another message passes over the intercom. Each day, we run a gauntlet of distractions in the operating theatre. In the March issue of Anaesthesia, Van Harten et al. report their observations of 64 staff members lasting 148 hours in an effort at quantifying case-irrelevant verbal communication, smartphone usage and other distractions in the operating theatre. Qualitative research was performed with the collation of vignettes and by obtaining the perspective of participants on the importance of disruptions. In the accompanying editorial by Shelton and Smith, the double-edged sword of the smartphone in daily practice is discussed. Used optimally, the device may be more of an enabler of safety than a threat to it. The outcome is in our own hands – literally.

Figure 1 Relative importance of the distractors during incision to closure in three studies. Interference (frequency x impact) during surgery caused by different sources. Smartphones were not counted in earlier studies. The pattern in all studies is similar. CIC, case‐irrelevant communication.

How has this pandemic affected our learning as anaesthetists? Fawcett et al. look at the challenges faced in the dissemination of scientific knowledge during the COVID pandemic. During the past 12 months, the need for timely peer review and release of educational materials has coincided with a threat to some of our most trusted methods of accessing them. From challenges with journal printing and distribution to the cancellation of scientific meetings, novel and additional efforts have had to be made to place the journal’s offerings in the hands of its readers. Have we found better ways of doing things that should remain long-term? This journal has increased its use of twitter and podcasting. More recently, we have added live broadcasting to our armamentarium. Our enhanced social media presence was accelerated by the pandemic but we do not envisage this as a short-term effort. Instead, we expect twitter, podcasting and live broadcasting to become permanent fixtures of the broader conversation with our readers. 

COVID-related research continues to feature prominently in this journal. At the onset of the pandemic, concerns regarding occupational COVID-19 risk were greatest for anaesthesia and intensive care staff, and in particular their proximity to aerosol-generating procedures and patients utilising respiratory support devices. An editorial by Cook and Lennane explores this area by comparing expected and actual mortality and the implications of the findings on staff and patient safety. This pandemic has resulted in a re-appraisal of the risks of benefits of regional and general anaesthesia in some scenarios. Bhatia et al. examine the impact of COVID-19 on general anaesthesia rates for caesarean section across six maternity units in the north-west of England and hypothesise as to why this pandemic could influence our decision-making processes. With respect to critically ill patients with COVID-19, this journal issue contains two retrospective reviews on the impact of renal impairment and of high-intensity pharmacological thromboprophylaxis on clinical outcomes in this setting. As each month passes, our COVID-19 knowledge base grows, but as some uncertainties resolve, others arise.

Irrespective of any pandemic, the access of surgical patients to critical care units for postoperative care has always faced challenges. Understanding them has perhaps never been more important. Which patients should be admitted to critical care post-operatively and who should be managed at ward level? What are the main benefits of peri-operative critical care admission and what are the challenges faced in the provision of this care?

The answers to these questions were amongst those sought as part of the second Sprint National Anaesthesia Project. Quantitative and qualitative analyses of the survey responses of 10,383 clinicians from 237 hospitals across the UK are reported in this month’s issue of the journal. The decision-making process is complex and coloured by experience. Clinicians face real pressures to deviate from their preferred care pathways when the ability to perform surgery is threatened by limitations in critical care provision. 

Figure 2 Thematic summary of respondents’ comments on critical care capacity.

Perhaps second only to sugammadex, dexmedetomidine is the pharmacological agent that has seen greatest acceleration of use in anaesthesia practice this past decade. In a previous issue of AnaesthesiaLee-Archer et al. examined the impact of dexmedetomidine on post-operative behavioural changes in childrenAn accompanying editorial by Bailey explores the broader evidence base for this alpha-2 agonist in paediatric anaesthesia, placed in the context of real-world considerations such as cost and pharmacological alternatives. Should dexmedetomidine become a staple of the day-case surgery routine or is the evidence base lacking for further expansions in use?

Regional anaesthesia – old and new – also features in this issue. In celebration of the 75th anniversary of Anaesthesia, we continue our look at some of the journal’s seminal papers in our Contemporary Classics series. This month, we have selected an article from the 1960s – an analysis by Dawkins on epidural complications. In their review, Collins and Yentis explore how both neuraxial blockade and the make-up of scientific publications have changed over the last fifty years. Whether it relates to indications, technique, equipment, dosing or awareness of complications, clinical practice has certainly evolved! Meanwhile, two systematic reviews and meta-analyses examine the evidence for fascial plane blocks. El-Boghdadly et al. compare quadratus lumborum and transversus abdominis plan blocks for caesarean delivery, while Leong et al. examine the efficacy of erector spinae blocks in breast surgery

Figure 3 Methods of identifying the epidural space used by Dawkins in 2145 cases (in the remaining cases, Odom’s indicator was used but no figures are given for dural puncture).

Clotting is another area of focus in this month’s journal. What is the role of four factor prothrombin complex concentrate in haemostatic resuscitation during surgical procedures? Members of the Transfusion and Haemostasis Subcommittee of the European Association of Cardiothoracic Anaesthesiology summarise the available evidence for dosing, efficacy, drug safety and monitoring in different scenarios and issue a consensus statement on the use of this agent. Meanwhile, Oberladstätter et al pubish a prospective observational study of the rapid detection of clinically relevant plasma direct oral anticoagulant levels following acute traumatic injury.

Elsewhere, Blackburn et al. compare CT scans and ruler measurements of three commonly used manikins with human CT scans. The translatability of airway manikin research into clinical practice has always been a contentious matter, with the most fundamental concern being the anatomic accuracy of manikins. Also, Trentino et al. perform a cost-effectiveness analysis of the screening and treatment of suboptimal iron stores in elective colorectal surgery. The great iron debate rolls on!

Keep an eye on our twitter feed for the latest journal article releases, links to new podcasts and future live broadcasts. We hope you’ll find them to be positive distractions!

Craig Lyons and Andrew Klein

Between evidence and aerosols

In the February issue, we are delighted to publish the articles by Brown et al., Dhillon et al. and the associated editorial by Nestor et al. Brown et al. report that both tracheal intubation and extubation sequences produce less aerosol than voluntary coughing (Fig. 1). On the other hand, Dhillon et al. find that tracheal intubation and extubation are aerosol generating procedures (Fig. 1) Who is right? The answer is probably that neither group is right or wrong, and differences in the experimental methods used might instead account for their different findings. This is all summed up nicely in the associated editorial and podcast.

Figure 1 Simulation of aerosol measurement approach within operating theatre environment. The sampling funnel was positioned 0.5 m above the source of aerosol in the airway management zone allowing a sampling stream of air (1 l.min−1) to be routed to the optical particle sizer.

When we use local anaesthetic agents in clinical practice, we usually go to great lengths to avoid local anaesthetic systemic toxicity, so injecting local anaesthetic agents intravenously might seem counterintuitive. That said, any anaesthetist who has used intravenous lidocaine as part of their peri-operative analgesic strategy will no doubt stand by the safety and efficacy of its use. This new guideline is the first of its kind, which is surprising as the use of intravenous lidocaine for analgesia seems to be widespread. It will hopefully provide a framework for hospitals and departments to write their own protocols, as well as standardising practices more generally. In the associated editorial, Pandit and McGuire discuss the evidence as well as the issues raised by using intravenous lidocaine as an unlicensed medication. They instead provide ‘a license to stop an infusion’ if a clinician encounters a patient in their care and they do not believe the drug to be efficacious. You can listen to both groups of authors debate the arguments for and against on the relevant podcast.

Which is best for patients with hip fracture, spinal or general anaesthesia? Thankfully, and although anaesthetists might always see this as an interesting talking point, guidance and expert opinion have moved beyond the debate of superiority of one mode of anaesthesia over another. Instead, and 11 years since the last iteration, this new guideline shifts focus onto areas such as anaemia, anticoagulation and getting patients to theatre in a timely manner. Direct oral anticoagulant agents seem to be the new major issue facing anaesthetists, and many will be pleased to see something on this topic written down. Again, the paper also has an excellent podcast where you can listen to Iain Moppett and Ciara O’Donnell take us through all the peri-operative considerations and controversies.

Constipation is common in critically unwell adults and this new study from Launey et al. suggests some associations and clinical implicationsThe associated editorial from Charlesworth and Ashworth discusses the many limitations of research in this area more generally and compares it with something more widely studied and understood – delirium. On the back of the recent regional anaesthesia supplement, Mariano, El-Boghdadly and Ilfeld present their thoughts this month in an editorial about postoperative pain trajectories and personalised pain medicine. They argue that If we knew the typical pain trajectories and patterns of postoperative pain regression and resolution for common surgical procedures, the data could guide our approaches to regional analgesia. Is it time to put the horse back in front of the cart? We think so! Few diseases in healthcare are as controversial and emotive as obesity. This new editorial from Selak and Selak has generated a lot of interest on social media as well as several items of correspondence. They argue that an empathetic approach to all patients, including those with obesity, may in fact be more patient‐centred and also protect against litigation.

Last but by no means least we have three excellent reviews this month which have all been extremely popular on Twitter. First, this airway management guidance document for the endemic phase of COVID-19 sensibly points out that current evidence does not support or necessitate dramatic changes to choices for anaesthetic airway management (Fig. 2). Second, this systematic review from Koyuncu et al. finds that trials on postoperative pain management after total hip and knee arthroplasty reported numerous outcome measures with heterogeneous timing of outcome assessmentFinally, Mallama et al. find that the peri‐operative route of paracetamol administration, intravenous vs. oral, did not affect pain or any other postoperative outcome. There was simply insufficient evidence to exclude important clinical effects and the quality of evidence overall was poor.

Figure 2 Aerosol generation during supraglottic airway (SGA) use: risk‐factors and considerations. AGP, aerosol‐generating procedure.

To celebrate our 75th anniversary each month there will be a brand-new article looking at a seminal paper from a different decade. This month it is the 1950s, and Aitkenhead and Irwin take on the topic of deaths associated with anaesthesia. A striking feature is the difference between anaesthetic practice during the study period and modern anaesthesia. More than 10% of the deaths were categorised as “circulatory failure immediately following intravenous barbiturate injection”. You can read the full paper for free, forever! Elsewhere we have: a study of ultrasound-activated needle tip tracker technologya randomised controlled trial of intra-operative methadone vs. morphine on quality of recovery following laparoscopic gastroplasty; and a study looking at the effect of intra-operative intravenous lidocaine on opioid consumption after bariatric surgery. You can also check out what is new in Anaesthesia Reportswho recently advertised for a new Executive Editor, by going over to their homepage or Twitter account

We have recently published five live broadcasts, with topics including COVID-19 vaccines, regional anaesthesia, obstetric anaesthesia and critical care outcomes. We plan to keep refining these events and if you have any feedback for us, please let us know! In total, these have now received nearly 30k views!

Make sure you also check this new special issue of COVID-19 correspondence that was published just last week.

Mike Charlesworth and Andrew Klein