Burning the candle

This month, we are delighted to publish two studies from the SWeAT study investigator group. The first is a quantitative analysis of survey responses from 397 UK anaesthetic trainees on the safety and wellbeing of these doctors and the patients they treat. They conclude that stress, burnout risk, depression risk and low work satisfaction are common. Interestingly, negative psychological outcomes might be independently predicted by having: no children; more than three days of sickness in the previous year; less than one hour of exercise per week; and more than 7.5 hours per week additional non-clinical work. The qualitative paper focusses on themes from interviews with ten trainees, of whom most were in the higher risk group for burnout and depression. Suggestions include: contracted hours for non-clinical work; individuals taking responsibility for self-care; cultural acceptance that doctors can struggle; and embedding wellbeing support more deeply. 

Figure 1 Euler diagram displaying the proportion of all respondents categorised with high perceived stress, high burnout risk and high depression risk, and the co‐existence of these issues.

Brian Jenkins discusses fatigue vs. resilience and what can be done. Decreasing on-call requirements might be one suggestion, but this has important implications for training. Good role models are important, as is recognition of the process by which resilience is taught and learned throughout training. McCrossan et al. argue that looking after our own and our colleagues wellbeing should be a core element of training. Perhaps it is now time to increase the availability of mentoring, but, for this to happen, we need to train more mentors and have a better collective understanding of what mentoring is. 

In July, we published the first international consensus statement on the use of uterotonic agents during caesarean section. The paper was a success on social media and currently holds an Altmetric score of over 200. Doses of oxytocin for routine elective caesarean section are lower than in other guidelines, and higher doses are recommended for women at increased risk of postpartum haemorrhage. Monks and Palanisamy highlight some issues with the quality of literature on which the consensus statement is based. They offer the pragmatic suggestion that we should use the smallest possible dose of oxytocin in combination with proper stewardship. Perhaps future research should focus on the longer-term consequences of this potent neuropeptide. 

Is it safe to give propofol to those with allergies to egg? It’s time to answer the question once and for all, at least in children. Somerfield et al. identified 2608 children with a clinical food allergy, of which 304 were exposed to propofol. There were 13 potential reactions in ten children. One was deemed a probable allergy and it could not be excluded in another. Both reactions were non-severe. They conclude that, overall, propofol was safely administered to children with allergies to egg, peanut, soybean or other legumes. Anderson and Sinclair discuss allergy vs. sensitivity with specific examples. They argue the study by Somerfield et al. supports current consensus, and that the main risk factor for a peri-operative anaphylactic event is a previous history of a peri-operative reaction.

We already know that airway management research sometimes fails to address commonly used techniques in clinically relevant patient populations. This month, Lundstrøm et al. report data on the DIFFMASK score for predicting difficult facemask ventilation. They study 48,804 patient records and report a prevalence of difficult facemask ventilation of 1.1%. Age, increased BMI, the presence of a beard and neck radiation changes were identified as risk factors. In the accompanying editorial, El-Boghdadly and Aziz discuss the limitations of this evidence and on approaches that are known to improve FMV conditions, such as utilising neuromuscular blockade and optimising the patient’s position

Figure 2 a) Possible sequences of events relating to face‐mask ventilation (FMV) during anaesthetic induction with a traditional approach. There are three broad phases after induction, delineated by colour‐coded boxes: first check of FMV; then a choice of three options depending upon the ability to mask ventilate (neuromuscular blocking drug (NMBD)/immediate choice); then several consequences of those choices. Note that waking a patient up after difficult FMV (dashed red line) is rarely done, and administration of a long‐acting NMBD after difficult FMV was thought to be dangerous (dotted red line). Waking patients up in the third phase is only possible if suxamethonium is given. Green lines indicate successful outcomes, red lines indicate unsuccessful outcomes. Redrawn from 13 with permission. (b) Possible sequences of events relating to FMV during anaesthetic induction with an approach based on recent data. There are three broad phases after induction, delineated by colour‐coded boxes: administration of a long‐acting NMBD before checking FMV; then FMV; then the consequences, which could be either tracheal intubation, or if unsuccessful, the failed intubation algorithm.

Despite the existence of many guidelines for postoperative pain management, we do not always get it right for all patients and all procedures. This month, we describe the methods used for the development of evidence-based recommendations for procedure-specific pain management: PROSPECT methodologyThe first PROSPECT paper focusses on rotator cuff repair surgery, and recommendations include: an arthroscopic approach; systemic multimodal analgesia; interscalene brachial plexus blockade; i.v. dexamethasone; and opioids reserved for rescue analgesia. We look forward to seeing further articles describing specific approaches for other procedures. Elsewhere, we have: a study of postoperative delirium screeninga randomised controlled trial of the PECS-2 block for radical mastectomya prospective cohort study of extravascular lung water measurement in patients undergoing pulmonary endarterectomy; and the educational impact of the SAFE® paediatric anaesthesia course.

Over in Anaesthesia Reportswe have a description of three ventilatory techniques to maintain oxygenation in a patient undergoing laser tracheal tumour resection and a report of McArdle disease causing rhabdomyolysis following vaginal delivery. You can now comment on any of our articles using our new DISQUS function. Click on the comment button next to an article or go straight to the comment box at the end of the article. If you write an interesting comment, we will ask you to consider submitting it as a formal letter for publication.

Finally, we have all now returned from an excellent trip to Glasgow where we announced our 4th annual article of the year. Kariem El-Boghdadly simply blew the audience away with his presentation, which was streamed on multiple platforms and with all winners announced in real time on Twitter. You can watch his presentation here. The author of our winning article, Marcelle Crowther, flew in to collect her award from South Africa, along with her parents. Her paper is free forever and supports recommendations from the Joint Guidelines from the Association of Anaesthetists and the British Hypertension Society. Her colleagues from the department of anaesthesia and peri-operative medicine at the University of Cape Town watched her receive the award, and we watched them watch us. According to Nick Chrimes, we were all well and truly sucked into the vortex.

Dr Mike Charlesworth and Professor Andrew Klein

Smile for the camera!

Audio-visual recordings of doctor-patient interactions might have the potential to improve the consent process. Ivermee and Yentis report on the attitudes of postnatal women, anaesthetists, obstetricians and midwives towards audio recording of consent discussions. Most participants found the idea acceptable, yet some staff had concerns about confidentiality, technical difficulties, and the possible detrimental effects on the doctor-patient relationship and consent process. These concerns were not shared by most postnatal women. Combeer and Iqbal make a case for embracing such opportunities to improve patient care, and provide a balanced account on the pros and cons of audiovisual recordings of patient care. Such recordings are likely to become more common and our engagement is required to ensure this leads to positive outcomes for patients and anaesthetists.

Good quality antenatal information provision is a vital part of preparation for labour. Brinkler et al. surveyed 903 postnatal women across 28 London hospitals on the provision of anaesthetic and analgesic information during pregnancy and delivery. Concerningly, only 9% and 12.1% of women recalled receiving antenatal information covering all aspects of labour analgesia and caesarean section, respectively. Only 68.7% felt confident about their analgesic choices as a result. The authors call for better ways to deliver information to expectant mothers and this might require more collaborative ways of working.

Maternal satisfaction with anaesthetic care is a complex metric. Yurashevich et al. evaluated data from 4297 postpartum women to establish determinants of dissatisfaction with anaesthesia care in labour and delivery. Factors associated with maternal dissatisfaction following vaginal delivery included: pain intensity during the first and second stages of labour; postpartum pain intensity; delays of more than 15 minutes in providing epidural analgesia; and postpartum headache. Postpartum pain, headache and pruritus were associated with dissatisfaction after caesarean delivery. These findings reinforce the contribution of the anaesthetist to a positive birth experience, which might be improved by more rapid responses to epidural analgesia requests and by contributing more to postoperative pain management. 

The first international consensus statement on the use of uterotonic agents during caesarean section has now been published on Early View. This was our top paper on social media in July, with an Altmetric score of 225! It is essential reading for all obstetric anaesthetists and obstetricians, and it may also be useful to those sitting the FRCA exam. 

Haemostatic activation during cardiopulmonary bypass may lead to coagulopathy, or paradoxically, postoperative thromboembolic complications. Ho et al. evaluated the association between platelet dysfunction and adverse outcomes in cardiac surgical patients. They found that for every 1% increase in platelet dysfunction during the rewarming phase of cardiopulmonary bypass, there was an 1% increase in the incidence of adverse postoperative events. This was a secondary analysis of data obtained from the transfusion avoidance in cardiac surgery trial – which was a stepped-wedge, cluster randomised controlled trial. In the accompanying editorial, Charlesworth and Agarwal succinctly describe the basics of a stepped-wedge cluster design and discuss how the authors recycled an old dataset to answer a new research question. Importantly, they stress that the study by Ho et al. is not ‘salami sliced’ – an issue that Anaesthesia has a clear stance on

Figure 1 A schematic of a simple five cluster study conducted over six months. Clusters can be, for example, collections of different wards, theatres, hospitals or sites. Each month (or day, week or year), one cluster is randomised to cross over from control (black) to intervention (green). At the end of the trial, all participants are receiving the intervention.

Unplanned admission to critical care is associated with poor patient outcomes and increasingly used as a performance metric. Shelley et al. report on the association between anaesthetic technique and unplanned critical care admission after thoracic lung resection surgery. Their multicentre retrospective audit includes 11,208 patients undergoing lung resection surgery in 16 NHS thoracic surgical centres between 2013 and 2014. The most striking finding was that patients receiving total intravenous anaesthesia or thoracic epidural analgesia were less likely to have an unplanned admission to critical care. Licker remind us that these findings should be interpreted with caution for several reasons, and the conclusions drawn have already sparked much debate on Twitter. However, these findings are certainly hypothesis generating and should pave the way for well-designed prospective studies.

Current DAS guidelines recommend a scalpel-based technique as first-line for an emergency front of neck airway, but prospective data to support this are lacking. The recent study by Rees et al., which was recently featured in the popular #FrontOfNeck TweetChat, challenge these recommendations. DAS guidelines are only one of 38 published airway management algorithms, as highlighted in a directed review comparing and describing all difficult airway management algorithms published over the past 20 years. Whilst the frequency of algorithm publication has increased, many are overwhelmingly similar and data on implementation and outcomes are limited. An endorsed universal single airway algorithm is needed. Watch this space! 

Figure 2 Algorithm publication frequency from 1998 to 2018 with the number of publications per year (blue bars) and the number of cumulative algorithms published (orange bars).

Elsewhere, Jelacic et al. introduced an aviation-style computerised pre-induction checklist, as part of a quality improvement project, and demonstrated a reduction in the number of failures to perform all pre-induction stepsCarvalho et al. found that pre-operative voice evaluation of vowel phenomes has the potential to predict a difficult laryngoscopy. This is a novel finding and its potential incorporation in current airway assessment strategies requires further investigation. Crewdson et al., in a retrospective analysis of the Trauma Audit Research Network database, evaluated emergency airway interventions for patients admitted to major trauma centre. Over 70% of emergency department tracheal intubations were performed within 30 minutes of arrival. Worryingly, patients who required pre-hospital airway support and did not receive it had a higher mortality. This work suggests an unmet need for pre-hospital advanced airway management. Also, Lukannek et al. report on the development and validation of the Score for the Prediction of Postoperative Respiratory Complications (SPORC‐2) to predict the requirement for early postoperative tracheal re‐intubation.

Figure 3 Modifications made to the Anesthesia Patient Safety Foundation (APSF) pre‐anaesthetic induction patient safety checklist to create computerised version used for this study. The APSF pre‐anaesthetic induction patient safety checklist is shown on the left (a). A screenshot of the computerised pre‐induction anaesthesia checklist is shown on the right (b). Functionality of Checklist Navigator includes a checklist pull down menu, ‘Remote Display’ button, a case information window, ‘Reset Checklist’, ‘Close’, ‘Skip’ and ‘Undo’ button.

Promoting sustainable healthcare to medical practice has recently been recognised as an essential element of undergraduate medical education by the General Medical Council. Anaesthetists have been at the forefront of reducing the environmental impact of healthcare, and Shelton and White provide guidance on the leading role anaesthetists can play in developing and teaching this element of the undergraduate curriculum. They advocate a model from the Centre for Sustainable Healthcare which reduces environmental impact without adversely affecting health.

Figure 4 Driver diagram of the Centre for Sustainable Healthcare principles of sustainable clinical practice.

In our latest ‘Clinical Consequences’, Shah and Carlisle discuss and review the evidence supporting the use of cuffed tracheal tubes in paediatric anaesthesia. An updated meta-analysis shows they were changed one-sixth as often as uncuffed tubes. Sore throat was also less common with cuffed tubes, and the rates of laryngospasm and stridor were similar. Over in Anaesthesia Reports, an editorial from Dalay et al. summarises all the key learning points from the first issue, and Watton et al. report a case series of midpoint transverse process to pleura catheter placement for postoperative analgesia following video‐assisted thoracoscopic surgery.

Finally, we are looking forward to seeing everyone at Annual Congress in Glasgow next month. The Anaesthesia journal session takes place on Friday morning and Kariem El-Boghdadly will present the Anaesthesia article of the year. We look forward to finding out who made it into this year’s #AnaesTop10.

See you in Glasgow!

Dr Akshay Shah and Professor Andrew Klein

Future directions for obstetric major haemorrhage

Summer has arrived and we are back from an excellent 2019 Trainee Conference in Telford. Highlights included: a keynote lecture from Professor Colin Melville on the General Medical Council and training; a talk on awake breast surgery from Amit Pawa; a debate on the role of social media in the medical profession; and a conference dinner and dance under the planes at RAF Cosford.

This month, Sullivan and Ralph present the results from a single centre retrospective cohort study evaluating the use of intra-operative cell salvage in 6352 obstetric patients. Between 2008 and 2017, cell salvage was used routinely for 98% of caesarean deliveries at the authors’ institution. They found a reduction in blood transfusion rates during the study period, whilst also demonstrating that routine cell salvage seems to be safe and economical. These results contrast with the SALVO randomised controlled trial which found no evidence of benefit with cell salvage. Wong and Toledo eloquently discuss the differences between observational studies and randomised controlled trials, which is always a hot topic on Twitter. They suggest further research is necessary before completely condemning the routine use of cell salvage, which is possibly at odds with the recent Association of Anaesthetists cell salvage guidelines

Point-of-care viscoelastic haemostatic assays are becoming increasingly popular. McNamara et al. present four years of prospective data following the introduction of a ROTEM algorithm for the treatment of coagulopathy in major obstetric haemorrhage (Fig. 1). They found a reduction in the use of blood products and the number of patients with transfusion associated circulatory overload. Most women experiencing haemorrhage did not have any evidence of coagulopathy, except in cases of placental abruption. Shah and Collis therefore ask, should we abandon the use of fixed ratio blood products in obstetrics, and should hypofibrinogenaemia be treated with cryoprecipitate or fibrinogen concentrate? These questions aside, knowledge of early haemostatic competence does have the potential to influence clinical management. If early results are normal, the focus can shift towards surgical causes of bleeding and allogeneic transfusions may be avoided. This is perhaps where the true benefit of using these new assays lies in the context of obstetric practice.

Figure 1 Number of units of blood and blood products per patient.

The use of dexamethasone as an adjunct to peripheral or central neuraxial blockade is controversial. Albrecht et al. report their randomised, triple-blind study to evaluate the effect of increasing doses of perineural dexamethasone on analgesia duration in patients requiring an interscalene brachial plexus block. They observed that perineural dexamethasone, with doses ranging between 1-4 mg, prolongs the duration of analgesia in a dose-dependent manner. Heeseen et al. undertook a meta-analysis to investigate the effect of intravenous dexamethasone on postoperative analgesia when given after spinal anaesthesia. They observed a significant reduction in 24-hour morphine consumption and significantly longer time to first analgesia request in the dexamethasone group as compared with the control group. Marhofer and Hopkins argue that, although there is no evidence that dexamethasone for regional anaesthesia causes harm, there are many good reasons why the evidential bar for a clinical benefit has not been met, yet.

Medication errors in peri-operative practice are commonSivia and Pandit have developed a new mathematical model to predict drug errors, which also incorporates the effect of operator fatigue. They observed that ~10% of operations lasting ~12 hours will result in a drug error, which is unacceptably high but consistent with other studies. Risks may be mitigated by anaesthetists recognising contributory factors such as illness, fatigue and working in unfamiliar environments. There have been many calls to move beyond labelling such problems as ‘human error’ and instead focus on continuously engineering human-centred safety systems. Carlisle and Merry discuss the science of reducing failure, and the possible applications and limitations of this new model. Time will tell us whether the safety of anaesthesia will improve as a result.

Figure 2 Modelling the probability of error over the course of an operation in which there are five drugs and tree possible routes for injection for three intrinsic error rates of 0.1% (green), 1% (blue) and 10% (red). The same result obtains for a scenario of three drugs and five possible routes for injection.

Excessive ambient noise in the critical care environment is a common patient compliant and can have negative sequalae. To address this problem, we must first isolate the source of the noise. Darbyshire et al. mapped the source of noise on a critical care unit and observed most loud sounds originated from very limited areas that were very close to patients’ ears. These noises may originate from bedside equipment and monitoring alarms, and simple redesign measures may be an effective way to reduce this environmental noise burden (Fig. 3).

Figure 3 Heat map which can be interpreted as average ‘noisiness’ map for the ICU bay. ‘Hotter’ colours (reds and yellows) indicate areas where loud noises are more frequent. The area of noise marked ‘1’ is outside the side room that was preferentially used, and shows where conversations between staff about the patient in the side room commonly took place. The areas of noise marked ‘2’ correspond to the positions of the telephones.

Bertaggia question the evidence we use to inform peri-operative practice through calculating the Fragility Index of all peri-operative randomised controlled trials reporting a significant effect of an intervention on mortality. They found that, for most trials, the significance of interventions was sensitive to only a few more deaths amongst participants. They suggest trialists should consider reporting the Fragility Index with studies, which is the number of participants without events who would have to experience events to increase p to ≥ 0.05. We look forward to inevitable debate over on Twitter! The first issue of Anaesthesia Reports has now been published! Recent reports include critical illness following topical application of a skin-lightening preparationmajor haemorrhage following vascular injury during exchange of cardiac pacemaker leadspre-operative ventricular bigeminy and cardiomyopathy; and critical illness in a patient with influenza A and sick cell trait.

Elsewhere, Weatherall compare portable blood warming devices under simulated pre-hospital conditions; Ki et al. find that a new EEG monitoring system (phase lag entropy) might be a useful hypnotic depth indicator in patients receiving propofol sedationKotoda et al. compare different methods of rigid stylet removal to minimise adverse force and tracheal tube movement; and Bojesen find that hypoxaemia after surgery for colorectal cancer is perhaps much more common than we might expect.

We recently issued two press releases for important articles with implications for anaesthetists, departments and hospitals. You can read all about peri-operative transoesophageal echocardiography-related complications and the Association of Anaesthetists survey on suicide amongst anaesthetists over on early view. Both articles are free forever. Finally, we are delighted to announce that our 2019 Impact Factor has increased by 8% to 5.9, according to the yearly Journal Citation Reports just published by Clarivate. Our journal is ranked 4th out of 31 in the category “Anesthesiology” and was the only journal in the top four to increase its Impact Factor in this year’s Report.


Professor Andrew Klein and Dr Akshay Shah

Getting it right first time

This month, in a stinging editorial, Professor Pandit argues a lack of rational data on theatre performance and efficiency make the NHSI report on operating theatres an almost worthless read. It is perhaps the claim that list over-runs are due to late starts or gaps between cases that will strike a chord with clinicians. He argues such claims are not backed by evidence and are at odds with existing literature. This editorial is a must read for all theatre staff and you can read a response from one of the report’s authors here.

Tranexamic acid has revolutionised the management of traumatic and non-traumatic haemorrhage following the publication of the landmark CRASH-2 and WOMAN trials. Whilst the peri-operative benefits of tranexamic acid are well documented, Patel et al. provide data on catastrophic drug errors that have arisen as a result of intrathecal administration. They identified 21 cases with a mortality rate of just under 50% (10 out of 21 cases). Of the remaining 11 cases, 10 required ICU admission for refractory convulsions and/or tachyarrhythmias with a high incidence of permanent neurological injury in survivors. Perhaps the most worrying (and disappointing) finding is that an ampoule error (i.e. not checking or reading the label, similar size ampoules) occurred in 20 patients. This is unsurprising, given the similarities shown in Figure 1In the accompanying editorial, Palanisamy and Kinsella discuss potential causes of such errors and provide practically useful solutions to reduce the risk of such rare, but catastrophic errors, down to zero

Figure 1. Similarity of tranexamic acid and bupivacaine ampoules.

Gastric ultrasound is becoming increasingly popular. Studies so far have used a variety of different participant positions to evaluate gastric volume using ultrasound, and the ideal position is unknown. Bouvet et al. address this by evaluating the effect of different patient positions and different bed angles on gastric ultrasound contents in healthy volunteers. They found the angle of the bed can significantly affect ultrasound performance, and a 45°angle performed the best to detect gastric fluid volume > 1.5 ml.kg-1. Nascimento et al., in a non-inferiority randomised trial of labouring women, observed that maltodextrin was cleared from the stomach faster than coffee with milk and orange juice. These studies add to the growing body of evidence suggesting gastric emptying and volume are not solely dependent on volume ingested and total calories, but also on other factors such as protein and lipid content and patient positioning. Mohta et al. carried out a randomised trial of 100 mg phenylephrine boluses versus 5 mcg noradrenaline boluses to treat maternal postspinal hypotension during elective caesarean section. They hypothesised that noradrenaline would be less likely to cause bradycardia, due its weak b-agonist chronotropic action. Results showed no difference in the primary outcome of bradycardia, but the total number of phenylephrine boluses required was, perhaps unsurprisingly, greater than noradrenaline. Interestingly, the umbilical artery pH, bicarbonate and base excess were lower in the noradrenaline group which could have been as a result of placental transfer, but the mechanisms and clinical implications of this requires further investigation. 

Reducing the environmental impact of anaesthesia is a key strategic issue for the Association of AnaesthetistsKennedy et al., in a quality improvement study, provide novel data on how a single episode of high fresh gas flow at the start of anaesthesia can have a significantly modifiable effect on overall gas flow and vapour consumption. The authors provide us with useful conceptual framework (Figure 2) that suggests we need to be more mindful of our gas flows during induction. Hade et al. modified an existing central line insertion checklist by recommending insertion depths and adding a picture of a chest radiograph with a traffic light coloured tick-box system to assist with post-insertion tip confirmation (Figure 3). They report an impressive reduction in line tip malpositioning, along with improvements in documentation of other components of the checklist such as sterility measures. 

Figure 2. The three factors that are directly under the control of the anaesthetist that determine overall fresh gas flow (FGF) and vapour consumption: (1) the initial (high) FGF; (2) the duration of the initial FGF; (3) the FGF during the maintenance phase.

Figure 3. Central venous catheter checklist accompanied with the traffic light system.

Elsewhere, Luther et al., in a bench top study, observed that the brand of bougie, brand of double-lumen tube and size of double-lumen tube all influence the degree of bougie fragment shearing. This has implications for tube manufacturers who may consider specifying in advance which bougie could be safely used with their double-lumen tube. Dingley et al. investigated the effect of temperature control in different designs of emergency drug transport bags, which can have important consequences on the efficacy of emergency drugsGratz et al. successfully demonstrated the uptake of thromboelastometric-guided algorithms in emergency departments with no previous experience of such technology. Implementation of such algorithms has the potential to improve outcomes in patients with traumatic brain injury and suspected haemorrhage. 

In our reviews section, Roth et al. performed an excellent and highly clinically relevant abridged Cochrane review on the beside accuracy of bedside tests for predicting difficult airways. They found that, although none of the current tests are well suited for detecting anticipated difficult airways, the upper lip bite test had the most favourable test accuracy properties with a sensitivity of 67% and specificity of 92%. In the accompanying editorial, Law and Duggan discuss the challenges of current airway assessment strategies, offer advice on what to screen for and how to act if difficulty is predicted and suggest directions for future researchPoldermans et al. found no evidence that perioperative dexamethasone increases the risk of developing wound infections. It did produce a transient increase in glucose levels by a mean difference on 0.7 mmol.l-1, but data were on patients without diabetes mellitus. Surprisingly very little evidence currently exists on glycaemic control in patients with diabetes who receive dexamethasone, but the results of a large trial (8800 patients) with stratification of diabetes status are awaited. Some of the issues around dexamethasone administration and diabetes are discussed in an editorial by Albrecht and Wiles. They primarily focus on the some of the key findings of a recent NCEPOD report which reviewed the care of patients with diabetes who underwent surgical procedures. The authors make a strong case for departments to have clinical leads for the perioperative management with diabetes, alongside better utilisation the existing expertise of diabetic nurse specialists and better recognition of inadequate diabetic control in the operating theatre. 

Over on Anaesthesia Reports, we have two new cases – one on the use of high flow nasal oxygen in a high-risk obese patient requiring sedation in the prone position, and another on awake tracheal intubation for blunt airway trauma. We hope you enjoyed our most recent #FrontOfNeck TweetChat as much as we did. We were never really going to definitively settle the scalpel vs. cannula eFONA debate, but some of the associated discussions were fascinating! Finally, we look forward to seeing you at Association of Anaesthetists Trainee Conference in early July. Matt Wiles will be discussing evidence-based advances in trauma, Mike Charlesworth will be discussing contemporary mechanical circulatory support and Andy Klein will be presenting some of the best papers from Anaesthesia.

See you in Telford!

Professor Andy Klein and Dr Akshay Shah

Fluid warmers and aluminium toxicity

Summer is almost upon us and we have a bumper issue of Anaesthesia lined up for you this month. In a landmark study Perl et al. report that uncoated aluminium plates in the CE-marked enFlow® fluid warming system release aluminium when used with a balanced crystalloid solution at levels far above FDA-recommended limits. The short and long-term clinical implications are unclear at present, but the manufacturer of enFlow® recently issued a global market recall. This received widespread attention from many news outlets, including The Guardian. Long-term sequelae of aluminium toxicity may include neurological impairment, Alzheimer’s disease and metabolic bone disease. Professor Exley, a chemist from Keele University and a recognised aluminium toxicity expert, argues a full investigation is now required. In the accompanying editorial, Charlesworth and van Zundert make a strong case for clinicians to be at the forefront of research on commonly used medical devices whilst also promoting clinical vigilance. A newly published paper from Taylor et al. seems to validate the conclusions drawn by Perl et al., more so for other balanced crystalloid solutions and blood products. Watch this space for more news!

Figure 1.pngFigure 1 Sketch of fluid‐warming disposables with aluminium heating plate in the fluid chamber. a: parylene (purple)‐coated device; b: non‐coated device. PVC tubing is drawn in black and the aluminium plate is drawn in grey. Note in (b), the fluid is in direct contact with aluminium.

Articles related to transfusion medicine and patient blood management are always popular. In this month’s issue, Trentino et al., retrospectively investigated the interaction between anaemia and red cell transfusion and what effect transfusion may have on mortality and length of stay at various levels of nadir haemoglobin. They retrospectively analysed 60,955 surgical admissions and observed higher mortality with red cell transfusion at haemoglobin levels greater than 90 g.l−1, whereas at all levels below 90 g.l−1 mortality was not significantly different. This is an important study which adds to the evidence base supporting restrictive transfusion, but like most observational studies, it demonstrates an association and uncontrolled confounding is likely. In addition, the effects of restrictive transfusion strategies are still unclear in certain perioperative subgroups such as those with cardiovascular disease.

Staying on the theme of anaemia and transfusion, Keeler et al. report a secondary analysis of a previously published randomised trial that evaluated the effect of intravenous iron versus oral iron on haemoglobin and transfusion requirements in patients with colorectal cancer-associated anaemia. In this secondary analysis, they compared quality of life scores between both study groups using validated questionnaires such as the EQ-5D-5L, SF-36 and FACT-An. Intravenous was associated with higher quality of life scores across multiple domains as compared with oral iron three months following surgery. In their accompanying editorial, Shah and Bailey discuss some of the current challenges in measuring outcomes following surgery with regards the methods used to determine a minimum clinically important difference and the choice of outcome measurement tools.

Elsewhere, Oller et al. evaluated the effect of a novel crystalloid fluid (Oxsealife®) on recovery from haemorrhagic shock in pigs. One of the beneficial properties of this fluid is that it is able to generate microvascular nitric oxide and scavenge reactive oxygen species generated during the ischaemia-reperfusion injury. Through a series of experiments, they observed improvements in serum markers of organ function, oxygen delivery, and better maintenance of glycocalyx integrity in pigs receiving this fluid compared to those receiving whole blood. This is a very promising physiological alternative to blood in the management of haemorrhage shock and early phase human studies are warranted.

There is growing interest in the measurement and impact of frailty across all medical specialities, yet there is no gold-standard method to achieve this. Pugh et al. prospectively evaluated the inter-rater reliability of the Clinical Frailty Scale (CFS), on a variety of healthcare professionals, for assessing frailty in patients admitted to critical care. They used this tool based on the findings of a systematic review which identified the CFS as the most commonly reported frailty assessment tool in critical care. The CFS is a nine-category assessment tool (Fig. 2) that is easy to administer and a CFS rating >4 is considered frail. They observed a good level of inter-rater agreement in frailty assessment using the CFS but identified independent factors, such as the assessor having a medical background, which could influence ratings. In the accompanying editorial, Falvey & Ferrante discuss the challenges in defining frailty, and why it is important to assess for it in the critically ill patients.

Figure 2.pngFigure 2 Rockwood clinical frailty scale.

There is huge interest currently in the potential advantages of the peri-operative use of dexmedetomidine, and in this month’s issue, we have two such articles. Cheng et al. performed a multicentre randomised trial evaluating the effect of intra-operative dexmedetomidine on cognitive decline in patients aged >65 years undergoing elective gastrointestinal laparotomy surgery. They observed a reduction in cognitive decline up to one postoperative month, which was mechanistically associated with changes in serum brain-derived neurotrophic factor. Whether or not this beneficial effect persists at longer follow-up time points requires further investigation. Grape et al. also performed a systematic review comparing the analgesic efficacy on intra-operative dexmedetomidine with remifentanil. They found improvements in pain scores during the first 24 hours and fewer side effects in patients who received dexmedetomidine.

Gomez-Rios evaluated the performance of a new video laryngeal mask, TotaltrackTM, which combines a supraglottic airway with a videolaryngoscope (Figure 3). The device was found to be acceptable in 300 patients, though further studies comparing it to current standards of airway management are required to determine its precise role in airway management. Boisson et al compared a non-invasive, cardiac output photoplethysmographic device (Clearsight) with a conventional PiCCO device in 20 adults undergoing elective surgery. They observed no differences in overall performance with regards to measuring absolute and changing stroke volumes. The non-invasive nature of this device may increase the uptake of goal-directed therapy.

Figure 3.jpgFigure 3 The Totaltrack video laryngeal mask and its components. Side and rear view of the device. 1. Videotrack; 2. memory card; 3. non‐rechargeable battery‐operated light; 4. supraglottic airway; 5. high‐volume, low‐pressure cuff; 6. rigid blade; 7. tip of the blade protected by a silicone cover; 8. intubation channel guide; 9. laryngeal suction channel; 10. gastric suction channel; 11. tracheal tube; 12. tracheal tube connector; and 13. distal aperture of the gastric suction channel.

In our reviews and guidelines section, we are pleased to publish the 2019 Association of Anaesthetists and British Association of Day Surgery guidelines for day-case surgery (Fig. 4). This is essential reading for all anaesthetists, clinical leads and theatre managers. Lastly, we have a very interesting, narrative review by Sepulveda et al. on neural inertia, a phenomenon that may explain the resistance observed to changes in consciousness induced by total intravenous anaesthesia, independent of drug kinetics.

Figure 4Figure 4 Key recommendations from the day-case surgery guidelines.

Over on Anaesthesia Reports, we have some fascinating articles on a triple regional analgesia technique for pleuropulmonary sarcoma resection, analgesia using a wound catheter after clamshell thoracotomy (Fig. 5), CSF-cutaneous fistula formation following accidental dural puncture, and delayed presentation of cardiac tamponade following traumatic diaphragmatic hernia repair. This case report from Saunders et al. has the highest Altmetric score from our new journal. Congratulations to the authors!

Figure 5.jpgFigure 5 Intra-operative placement of a wound catheter.

We are sad to report that two of our senior editors are stepping down after many years of service at the journal. Good luck to Professor Jaideep Pandit and Dr Stuart White on their future endeavours. We have appointed several new editors including Dr’s Laura Duggan, Seema Agarwal, and two of our previous Trainee Fellows, Helen Laycock and Kariem El-Boghdadly. Finally, we have a new system for manuscript submissions with separate sites for Anaesthesia and Anaesthesia Reports. Make sure you send us your work for an efficient, friendly and helpful peer review service.

Dr Akshay Shah and Professor Andrew Klein

A wider role for anaesthesia?

This month in Anaesthesia, Sinmyee et al. discuss the legal and ethical implications of defining an optimum means of achieving unconsciousness in assisted dying. They examine the means used to achieve unconsciousness from around the world and report a relatively high incidence of vomiting, prolongation of death and reawakening. That said, the very act of defining an optimum method for inducing unconsciousness in assisted dying has complex legal and ethical implications for the public, legislators and physician groups. In the accompanying editorial, Savulescu and Radcliffe-Richards argue the prevention of suffering at the end of life is hardly controversial, and we must consider the use of anaesthesia in this context. These papers, together with the accompanying commentary in the BMJ, are ‘must reads’ for all.

Rib fractures are a significant cause of suffering following blunt trauma and can lead to deadly pulmonary complications. This new retrospective cohort study suggests the erector spinae block improves respiratory function, pain control and haemodynamic stability in such patients. Similarly, Womack et al. find that paravertebral catheters are another safe and effective option. In their editorial, El-Boghdadly and Wiles argue thoracic epidural analgesia should no longer be considered a first line regional anaesthesia strategy in such patients. They summarise the evidence for other techniques such as paravertebral, intercostal, erector spinae, mid-point transverse process to pleura (MTP), retrolaminar, rhomboid intercostal, and serratus plane blockade. Confused as to which block goes where? Look no further than this excellent figure from @elboghdadly!

Figure 1Figure 1 Axial cross‐sectional illustration of a thoracic vertebra demonstrating the key anatomical structures (left) and the site of injection of local anaesthesia for blocks (right) used in the management of traumatic rib fractures. ESM, erector spinae muscle; SAM, serratus anterior muscle; SCTL, superior costotransverse ligament.

Given the many recent advances in regional anaesthesia and analgesia, is intra-operative opioid administration still necessary? This new systematic review and meta-analysis suggests ‘opioid-inclusive anaesthesia’ does not reduce pain and is associated with postoperative nausea and vomiting. The accompanying editorial by Elkassabany and Mariano has already been extremely well received on Twitter! They set out the case for multi-modal analgesia and derive a new definition for opioid free anaesthesia – “a peri‐operative care strategy that maximises non‐opioid modalities for anaesthesia and analgesia and reserves the use of opioids for severe acute pain unrelieved by other methods from admission to discharge from the hospital”.

Figure 2Figure 2 Infographic showing one approach to practically applying multi‐modal analgesia; some modalities should be considered for all patients (except when contraindicated), whereas other modalities should be considered for some patients (only when indicated).

In February, we facilitated a TweetChat on this new analysis by Myles, Carlisle and Scarr (#Hyperoxia). Their article challenges the integrity of data from studies of liberal peri-operative inspired oxygen by Mario Schietroma’s group, and provides an updated systematic review and meta-analysis of supplemental oxygen and its effect on surgical site infections (SSIs). The figure below seems to suggest a lack of evidence to support the recent WHO guideline on preventing SSIs, and the debate looks set to continue!

Figure 3Figure 3 Updated systematic review and meta‐analysis: forest plot of supplemental oxygen‐surgical site infection trials.

New neuraxial and regional anaesthesia non-Luer connectors will soon be coming to a hospital near you. This new evaluation of the non-Luer ISO 80369-6 connector finds it to be acceptable in terms of its ease of use, reliability, lack of leakage and versatility. It is hoped these new devices will solve the problem of neuraxial-i.v. wrong-route errors.

Figure 4Figure 4 Illustrations of NRFit (ISO 80369‐6) connectors. Top left. male slip connector, with floating collar; top right, male lock connector, bottom left female connector from the side and bottom right, oblique view. The neuraxial non‐Luer connector (NRFit) retains the approximate appearance of a Luer connector, with a proximal conical male component fitting into a receiving female component. The 5% angle of the cone and its dimensions differentiate it from a Luer device (6%). Additional features are ‘lugs’ in the distal male cone to reduce the chances of a leak‐free misconnection with other connectors and a floating collar on the male slip connector to create an additional barrier to misconnections.

Elsewhere we have a systematic review of  the analgesic efficacy of the Pecs II block, a study of postoperative microcirculatory perfusion and endothelial glycocalyx shedding following cardiac surgery with cardiopulmonary bypass, a comparison of sufentanil vs. remifentanil in fast‐track cardiac surgery patients, a synopsis of the recent legal challenges to the concept of brain death in the USA, Canada and the UK, and the new Association of Anaesthetists guidelines for the safe provision of anaesthesia in magnetic resonance units.


Over in Anaesthesia Reports, we recently published five new papers including a description of the MTP block for surgical anaesthesia, reversal of clonidine with naloxone, cord injury following spinal anaesthesia, ECMO-CPR for drowning and pulsed radiotherapy of the brachial plexus. All reports (including our entire back catalogue) are open access for a limited introductory period and you can submit your interesting reports (including pictures, videos and much more) here. We have already accepted a number of excellent new reports and you can keep an eye out for new material on the Anaesthesia Reports homepage.

Dr Mike Charlesworth and Professor Andrew Klein

Harmful effects of sleep deprivation – it’s in the genes!

The association between sleep deprivation and poor health outcomes is well-recognised. In this month’s issue of Anaesthesia, Cheung et al. conducted a mechanistic study aiming to unravel the effects of sleep deprivation on DNA damage in healthy, full-time doctors. Doctors who worked on-site overnight shifts had higher levels of oxidative DNA damage and lower DNA repair gene expression when compared to those did not work overnight shifts. These changes were detected even after only one night of sleep deprivation. The authors should be congratulated on their work which attracted attention from over 20 news outlets and racked up an Altmetric score of >1000 in a just under one week. This is a timely study in view of the Association of Anaesthetist’s current #FightFatigue campaign. In an accompanying editorial, Fuller and Eikermann provide suggestions for future research on how we can build on the findings from this study.

In this month’s issue, we have a series of articles dedicated to elucidating some of the mechanisms underlying high-flow nasal oxygen (HFNO) therapy, which is becoming increasingly popular in anaesthesia, perioperative medicine, and intensive care. One area of interest is carbon dioxide clearance. Hermez et al. carried out a laboratory study of three physical airway models and through a series of clever experiments, which included three-dimensional printing of trachea models, they observed that carbon dioxide clearance may be facilitated by cardiac. Shippam et al., in a randomised physiological study of healthy, non-labouring healthy pregnant patients, found that pre-oxygenation with HFNO performed worse than standard facemask oxygenation. There are important caveats to this study including the use of end-tidal oxygen concentration as a surrogate for adequate oxygenation, the exclusion of obese patients and those with difficult airways, and its efficacy was not tested in an urgent/emergency scenario. Given the current enthusiasm regarding HFNO, these findings certainly warrant further investigation. An accompanying editorial by Lumb and Thomas and a narrative review by Lyons and Callaghan succinctly describe the underlying mechanisms of HFNO and the evidence-based supporting its clinical application.

Figure 1

Figure 1 Apnoeic oxygenation involves the mass flow of a high fraction of inspired oxygen, aided by flushing of dead space, generation of positive airway pressure and cardiogenic oscillations. Higher flow rates can enable clearance of carbon dioxide.

We all fear being involved in a ‘cannot intubate cannot oxygenate’ scenario. Adequate training in emergency front of neck access (eFONA) is therefore crucial. Le Fevre et al. evaluated a novel obese-synthetic manikin against an obese-meat manikin and a conventional slim manikin. They observed that eFONA times were significantly longer in both obese manikins when compared to the slim manikin. The obese-synthetic manikin’s performance was broadly similar to the obese-meat manikin, with the added advantages of hygiene and convenience. If your department provides training in emergency front of neck access, this model is worth considering.

Figure 2

Figure 2 Three manikins (a) obese-synthetic; (b) obese-meat; and (c) slim

In the first of two articles related to human factors, Chrimes et al. discuss strategies on utilising human factors knowledge to improve the design of airway trolleys. One recommendation is to minimise the number of devices available in the trolley to simplify decision-making and avoid ‘analysis paralysis’. Another important and often underappreciated recommendation is to standardise difficult airway trolleys across all areas where difficult airway management can occur e.g. ICU, ED, theatres, recovery. In the second article, Evain et al., in a prospective, randomised, simulation study, demonstrated that a planning discussion before a simulated emergency scenario improved clinical team performance, crisis resource management, and stress response.

Figure 3

Figure 3 Icons facilitate locating equipment and integrate with cognitive aids.

The association between poor patient outcomes and out-of-hours admissions continues to be hotly debated. Goulden et al., studied 20,922 adults admitted to a UK critical care unit with status epilepticus over a 5-year period and found no evidence that weekend admissions were associated with higher mortality than those admitted during the week. Hepple et al., performed a retrospective analysis of the Trauma Audit and Research Network (TARN) database and found no evidence of a survival benefit in patients treated by an enhanced care team that included a pre-hospital physician. However, these patients were more likely to be younger, male and with a higher injury severity score. Rostin et al. conducted a large retrospective study investigating the effect of a single episode of postoperative desaturation (<90%) on discharge destination. They observed that early and prolonged desaturation was associated with greater odds of being discharged to a nursing facility. Several recognised, and potentially modifiable factors were identified including high intra-operative opioid use and high neostigmine doses. In an accompanying editorial, Coulson and Karalapillai question the biological plausibility of their findings, stress that ‘association is not causation’ and suggest useful methods for future research, such as nesting interventions within database studies where prospective randomised.

We also have three excellent review articles in this month’s issue. Smith and Plunkett, in a thought-provoking article, highlight recent developments in safety science and challenge the current approach of only addressing negative outcomes. We should also be promoting excellence through appreciative inquiry, positive deviance and excellence reporting and the authors provide practical and useful suggestions on how to achieve this.

Figure 4

Figure 4 An example of an appreciative conversation. Taken from EP’s work with appreciating people and reproduced with permission.

In the second of our Clinical Consequences series, Wojcikiewicz & El-Boghdadly provide a succinct review on analgesic strategies for day-case knee surgery. The authors conclude multi-modal analgesia should be the standard of care and that administration of local anaesthesia may only provide short-term analgesic benefits. Finally, Andersson et al. performed a systematic review of the anaesthetic implications of butyrylcholinesterase deficiency. They conclude that deficiency prolongs the action of succinylcholine and mivacurium by a few minutes to several hours and these effects are more pronounced with homozygous variants, increasing age, pregnancy, severe liver disease and burn injuries. A useful flowchart is provided on how to best manage these patients.

Figure 5

Figure 5 Flowchart to guide anaesthetists for managing patients with known or suspected butyrylcholinesterase deficiency.

Over on early view, this paper is certainly causing a stir! It seems uncoated fluid warming devices may result in the release of high levels of aluminium into infusion fluids. This research was recently featured as a leading story in The Guardian and the story continues to evolve, with the MHRA recently issuing a field safety notice. We hope you enjoy this month’s issue and we look forward to seeing your feedback over on Twitter as we make each paper #FreeForADay!


Dr Akshay Shah and Professor Andrew Klein