Occam’s razor

Occam’s razor (or the law of parsimony) is a problem-solving principle attributed to William of Ockham (c. 1287–1347), who was an English Franciscan friar, scholastic philosopher and theologian. The principle states: ‘other things being equal, simpler explanations are generally better than more complex ones’. This month’s blog looks at simple interventions and principles, and whether Occam’s razor hold true in our practice.

Paracetamol – great drug, right? I swear by it, and dispense it liberally, both at home and in the operating theatre and the intensive care unit. A simple study with a very simple hypothesis is published in October’s edition of the journal, comparing oral (enteral) with intravenous (parenteral) paracetamol in ICU patients. Patients who received the intravenous formulation were much more likely to suffer hypotension and require vasoconstrictors to ameliorate this. Wow – so paracetamol is not as harmless as we all think? If one off doses can cause hypotension like this should we still be giving it at all in our ICU patients, or should we only be giving it enterally (presumably via the NG tube – hypotension still occurred but less commonly)? Maybe this simple, effective drug is not the panacea? A very interesting study I am sure you will agree.

What about teaching tracheal intubation to novices? We have traditionally taught the use of the Macintosh laryngoscope first, but will they learn it and remember it better if they are taught with a videolaryngoscope? Actually, perhaps not – this excellent study studied a group of medical students and looked at skill retention. This study showed that the students learnt how to use the Macintosh, A.P. Advance™, C-MAC® and Airtraq® laryngoscopes equally well at first, but one month later, they seemed to have retained the skill-set required for laryngoscopy significantly better with the Macintosh and Airtraq laryngoscopes. In this instance, simpler seems to be easier to pick up again and get to grips with more quickly, a salutary lesson.

This month, we also publish an interesting systematic review of the effect of propofol compared with inhalational anaesthesia on postoperative outcomes including pain. This well-conducted rigorous review found that patients who received total intravenous anaesthesia with propofol did indeed have reduced pain scores 24 hours after surgery, although the effect size was quite small. But, it also confirmed that postoperative nausea and vomiting was markedly less common. Is this enough to make you switch your technique to TIVA? Maybe not, after all these are not really important outcomes like mortality, but will we ever recruit enough patients to see a difference in mortality if there was one – I doubt it. So what are we waiting for, or do we just not believe there is actually a difference? Perhaps it is simpler to believe the opposite, that inhalational and propofol are much of a muchness for maintenance of anaesthesia and we are not convinced either way yet.

Finally, our statistics article explains why odds and risks (and other numbers) often confuse things, both for researchers and for readers (consumers). Why do we like to use complicated statistics to describe things, when simpler explanations are often possible if not preferable? If you, like me, don’t know the difference between the odds of something and the risk of the same thing, then read it and learn – I did, and I am off to put a bet on the 2-30 at Newmarket…


Andrew Klein


The Olympics for anaesthetists

Well, that’s it for another four years. Months and years of preparations, and in the end it came down to five days of non-stop action and one night of celebration, then everyone goes home. This is the week that was the World Congress of Anaesthesiologists in Hong Kong, and what a good one it has been. I am going to give you a bit of a flavour of the event and how this journal fared at the pinnacle of our professional calendar of conferences.

The whole event was organised by Mike Irwin, Professor at Hong Kong University and one of the editors of Anaesthesia. Siu Wai Choi, the statistical advisor to this journal was also ever-present, coaching us to rise above any mathematical missed passes. However, John Carlisle, another editor of the journal, was the real star turn when he shared the podium with Steve Shafer (ex Editor-in-Chief of Anesthesia and Analgesia @stevenlshafer) and Nathan Pace (from the University of Utah and Senior Statistical Advisor at Cochrane). John presented his initial analysis of Fujii that led to the retraction of 183 publications and his undisputed Number 1 position on the Retraction Watch Hall of Shame (@RetractionWatch). He then presented the rationale for Monte Carlo simulation and his updated analysis – the Carlisle Method – which he announced he has now applied to all randomised controlled trials published over the last 15 years in this and seven other journals. Interestingly, another author has come to light after the application of the Carlisle Method following the submission of a suspicious manuscript to another journal, and this further analysis previewed at the World Congress will be published shortly in Anaesthesia.


One of my own personal highlights was the sight of the delegates queuing patiently to get hold of souvenir USB sticks containing the China Special Edition and World Special Edition of Anaesthesia produced especially for the Congress, and you can see these special editions yourself on our website by clicking on the links above. I also particularly enjoyed crossing the city to Hong Kong University to present a workshop to upcoming biomedical researchers on what and how to publish. The researchers packed the room and posed many questions about publication, research and the world of journal intrigue and peer review.



There was great interest at the Congress in several recently published articles. A Korean group presented their findings about complications during subclavian central venous catheterisation, and their conclusion that a wire-through-needle technique is safer than a catheter-over-needle technique should finally put to bed the longstanding debate about the two techniques. There were several fiery debates and discussions about routine or otherwise use of dexamethasone, with the presentation of data about the inescapable rise in glucose concentration associated with its use in diabetics and non-diabetics. Finally, novel regional blocks were much in evidence, and particularly the serratus anterior plane block, which was dissected in detail.

To finish up, a bit about the final night of celebration. A crowd of us were shown the sights of the harbor from the top deck of a boat, followed by a seafood dinner and even one or two local beverages. I understand that a number then went on to do a crawl around the top 10 rooftop bars of the city, but myself, I was tucked up in bed ready for the Closing Ceremony. I am sure everyone is looking forward to the next Olympics in Prague in 2020 – I certainly am.


Andrew Klein


Stop, Look, Listen, Think

The theme of this month’s blog is Safety (the capital S is deliberate). We teach road safety to our children by telling them to “Stop, look, listen and think” before crossing the road, and maybe as medical providers we need to try this too?

This month, researchers from Manchester publish an analysis of patient safety incidents reported to the National Patients Safety Agency (NPSA), now the National Reporting and Learning Service (NRLS), between 2004 and 2014 from critical care units in England and Wales. Of 1743 incidents, 389 (22%) may have contributed to the patient’s death, and 1555 (89%) may have been avoidable. Over the 10 years, the number of reported incidents per year went up, as did the number of patients cared for in ICU (but not enough to explain the increase in safety incidents). Why are patient safety incidents on the increase, despite our best efforts? Are we just reporting them more frequently? Or are they actually more common, despite the introduction of numerous guidelines, safety procedures and other central and local initiatives? Can we as medical practitioners and the ICU team as a whole do more? The study shows that there was a decrease in the number of incidents related to infection, but an increase in the number of medication incidents. There is certainly much to reflect on in this excellent analysis.

What about cricoid pressure? We were/are all taught to use it for rapid sequence induction, but, although a number of studies have cast doubt on its efficacy and safety, our practice hasn’t really changed. This month, a new study using ultrasound in awake volunteers shows that standard cricoid pressure does not actually narrow the oesophagus at all, let alone occlude it. This would be an interesting study to repeat in anaesthetised patients, but if it held true, does cricoid pressure do what we think it does? The authors also studied a newly described technique which they name paralaryngeal pressure. This was found to be much more effective at occluding the oesophagus, and certainly merits further study. the future of cricoid pressure is eloquently debated in the accompanying editorial, including its safety and when to release the pressure to prevent patient harm, and I urge you to read both the article and the editorial and join in the debate in our correspondence pages or on Twitter.

The final article related to safety describes an investigation modelling oxygen supplementation during tracheal intubation in pregnant women. Because pregnant women desaturate much more quickly during apnoea, rapid sequence induction can be more fraught and dangerous. Recent studies (THRIVE) have shown that high-flow nasal oxygen during intubation can prolong the time to desaturation during apnoea in the non-pregnant population. This most recent study demonstrated that increasing FiO2 at the open glottis increased the time to desaturation, extending the time taken for SaO2 to reach 40% from 4.5 min to 58 min in the average parturient model (not in labour). The greatest increases in time to desaturation were seen at FiO2 1.0, which could be delivered by high-flow nasal cannulae under ideal conditions. Obviously, clinical studies are needed in pregnant women, but my conclusion from this modelling study is – should we now be administering oxygen routinely via nasal specs during rapid sequence intubation, and certainly in pregnant women? Weighing up the risk-benefit model it would certainly seem to, and this may be a very significant change which will increase safety in this and other patient populations. I look forward to more research in this rapidly evolving safety field.

Finally, I am about to decamp to China (for the Chinese Society of Anesthesiology meeting) and Hong Kong (for the World Congress). I will be blogging from there with some special editions of the journal to coincide with these meetings and more updates on breaking research.


Andrew Klein


The times they are a-changin

Anaesthesia Blog, July 2016.

“The Times They Are a-Changin'” was a song written by Bob Dylan and released as the title track of his 1964 album of the same name. Ever since its release, the song has been influential to people’s views on society, with critics noting the general yet universal lyrics as contributing to the song’s lasting message of change, which seems particularly apt with Brexit and a new Prime Minister imminent. This month’s blog is also about change, and I particularly wish to highlight a Special Article on Pensions, Tax and the Anaesthetist. Over the last few years, a series of changes have been made to our pensions as doctors, and in April 2016 the biggest of these was introduced, with very little fanfare. Many of my local colleagues have not heard about the latest changes, and those that have are confused as to their effects on their pension. This article in the journal explains very clearly the changes that have been made and their effect on our expected pension income, and the choices we now have. There is no doubt that a good pension at the end of many years of hard work is one of the greatest incentives to working in the NHS, but can we still expect that and is there anything we can do to maintain our expected benefits? The changes to pension laws will increasingly affect workforce planning and may lead to even more experienced anaesthetists leaving the NHS – I urge you to read this and digest and discuss the implications.

I have noticed that there has been a marked change in attitudes to sedation over the last few years, and more and more of my non-anaesthetic colleagues want us anaesthetists to sedate their patients instead of anaesthetising them, because they perceive this to be better (though it is not always clear who for). The evidence comparing sedation and general anaesthesia is surprisingly sparse, but this retrospective propensity-matched cohort study in my centre demonstrated, much to our amazement, that sedation for high-risk patients with aortic stenosis undergoing transcatheter valve replacement actually had a number of significant advantages compared with GA, and our practice has now completely changed as a result, with more patients on a list, patients going home much sooner and everyone (patients and cardiologists/surgeons) much happier. An unexpected consequence is that the surgeons now think every patient should have sedation instead of GA, so the debate is set to continue for some time. I hope to see more trials comparing sedation with GA in the future.

Another interesting article in this month’s journal may herald a change in the local anaesthetic solution we use for regional anaesthesia. The authors compared liposomal bupivacaine with plain bupivacaine, and they found that the liposomal formulation provided up to 72 hours of analgesia when used for transversus abdominis plane (TAP) blocks. I think this is a very interesting development and I am sure we are going to read a lot more about liposomal local anaesthetic solutions in the near future.

Finally, there have definitely been changes to the way we teach medicine and anaesthesia, and particularly with respect to the use of simulators. Manufacturers have striven to develop advanced and technologically impressive simulation platforms, and a lot of surgeons now learn using cadavers, but this article compares a simple home-made meat model with cadaveric teaching for ultrasound-guided sciatic nerve block. Surprisingly, the cheap and simple home-made model was better for teaching novices than the cadaveric method, which will interest those running regional anaesthesia teaching courses and anyone teaching their trainees how to put in a nerve block. It seems simple is best under such circumstances.

I hope this month’s Anaesthesia will stimulate you to embrace change in your practice, and remember “Human happiness may rely on our ability to conquer a natural fear of upsetting the status quo”  (A. L. Kennedy).


Andrew Klein


Help – I need somebody!


I have to come clean – I borrowed the title of this blog from an editorial in July’s edition of the journal, which is my compliment to the authors. This famous song was not only sung by the Beatles in 1965, but also by John Farnham, Bananarama (another Bananarama song title in one of my blogs – that will get people talking), The Carpenters and many others. Calling for help, or communicating efficiently and effectively, is discussed in the aforementioned editorial on calling for help in the emergency situation, which is really about how we train our medical students and junior doctors to call for help. Knowing who to call and how is actually incredibly important. I was involved in a car accident recently, and it was obvious to me to call the police immediately, but everyone else was telling me not to bother. It was clearly the right decision, and we all know to call 999, outside of a hospital at least, but if an anaesthetic emergency is brewing, who should you call and how?

This excellent study compares two methods of urgent communication in theatre; one that is current teaching and a new Traffic Lights tool (‘red alert’, ‘amber assist’ and ‘green query). In a simulated theatre environment, the trainee anaesthetists instructed the go-between to relay information much quicker and more effectively using the Traffic Lights tool, and everyone involved preferred it to the situation, background, assessment, recommendation (SBAR) tool. Studies such as this one examining the effect of different communication styles and tools in the emergency setting are novel and, in my view, important. All the algorithms we refer to say “call for help”, but not who and how.

Understanding and communicating the risks of surgery to our patients is an important facet of healthcare, and this month we have published an interesting study linking caudal anaesthesia in children having hypospadias surgery with postoperative surgical complications. This was a retrospective, observational study, and the authors are not implying causation, only association, but it raises a number of interesting issues, such as mechanism (?swelling) and the need for a randomised controlled trial.

Pre-hospital treatment, communication between helicopter physicians and their patients about analgesia, is the subject of another article from the Swiss Alpine Helicopter Emergency Medical Service. Patients who clearly had a fractured limb most often received intravenous fentanyl, but the physicians who were trained anaesthetists used ketamine more frequently, especially for patients with reported severe pain or who had more severe injuries. This brings up up a number of questions: is ketamine better?; should non-anaesthetists be trained to use ketamine?; should ketamine be first-line for injured patients? I look forward to further research in this area of practice.

Finally, an editorial about the new NICE guidelines for the peripartum management of diabetes begs the question – how much did NICE actually communicate with anaesthetists who look after pregnant patients when drawing up these latest guidelines? The authors of this editorial certainly believe that the new guidelines are at best controversial, and that NICE should re-examine them as a matter of urgency as they confict with other recent NICE guidance. They pointed out that the new advice seems to follow historical strategies and does not give sufficient weight to more recent work, and that the recommendations will lead to an increased risk of maternal and neonatal hyponatraemia, as well as maternal hypoglycaemia. The authors of this editorial go as far as suggesting that obstetric anaesthetists should target a capillary blood glucose of 6 – 8 mmol.l−1 and use dextrose 5% in saline 0.9% with premixed potassium chloride 0.15% as the recommended initial substrate solution to run alongside the variable rate intravenous insulin infusion. There is clearly an urgent need for more and better communication between NICE and experts in this field. On that note, I am off to ring my insurance company and try and find out where my poor car is….


Andrew Klein


Blood – thicker than water?

Anaesthesia Blog, May 2016.

The first use of this phrase was probably in a German proverb (originally: Blut ist dicker als Wasser), Reinhart Fuchs by Heinrich der Glîchezære. By 1670, the modern version was included in John Ray’s collected Proverbs, and later appeared in Sir Walter Scott’s novel Guy Mannering (1815) and in Thomas Hughes’s Tom Brown’s School Days (1857). The June edition of Anaesthesia contains a number of articles that look at how thick blood actually needs to be and why this is important in the peri-operative period.

Anaemia is an increasingly prevalent condition, and has actually been described as an epidemic by the WHO. The Association of Cardiothoracic Anaesthetists (ACTA) undertook their first National Audit which is published here and describes how the rate of anaemia varies in different regions of the UK, from 23% to nearly double at 45%. The major finding of this study was confirmation of the association between anaemia and worse outcomes, and specifically that the lower the haemoglobin concentration is before surgery, the greater the chance of death is after cardiac surgery. In other words, thicker blood is good (except it seems if Hb > 150 g.l-1, which is also associated with increased mortality – is the blood too thick?).

Predicting which patients are more likely to bleed is one of the holy grails of peri-operative care, so that these high-risk patients can be targeted and actively managed. A group of authors used two point-of-care analysers to measure platelet function and found that a measurement performed soon after coming off bypass was best at predicting excessive bleeding. Tests performed at the start of surgery were not predictive, which is important as many manufacturers do recommend measuring at this point as a ‘baseline’, but this study suggests this may not be important. Also of interest was that patients taking pre-operative aspirin or clopidogrel were not more likely to bleed excessively, but anaemic patients were. Back to thicker blood is better!

Postpartum haemorrhage is the leading cause of maternal mortality globally, and this important study looked at the effect of platelets on major haemorrhage. Out of over 6000 deliveries over a one-year period, 356 (6%) women experienced moderate or severe haemorrhage, most commonly due to uterine atony, surgical bleeding or genital tract trauma. However, only 12 women required transfusion of platelets, which is much lower than in major haemorrhage due to trauma or following cardiac surgery, and this is a very interesting finding. Indeed, if the women had a normal platelet count before delivery and did not have placental abruption or other cause of consumptive coagulopathy, they had to bleed 5000 ml before requiring platelet transfusion. All this means that a fixed protocol including platelets is unnecessary for obstetric haemorrhage, and this is certainly relevant to clinical practice in every obstetric unit.

The final study that looked at bleeding was undertaken following major liver resection.  Not many anaesthetists look after these patients in the peri-operative period, but the authors finding that most patients were in fact less likely to bleed (were hypercoagulable – thicker blood?) after surgery, as measured using point-of-care tests, is relevant to all anaesthetists. This implies that instead of bleeding, most patients are at increased risk of thrombosis postoperatively, despite major surgery/transfusion, and that laboratory tests are in fact misleading during the immediate postoperative period. This would mean that prophylactic anti-thrombotic agents such as low-molecular weight heparin should be started earlier, and that laboratory tests should be replaced by point-of-care tests, a fact which is emphasised in this editorial. It really seems to me that the time has come to use point-of-care tests more widely, even once surgery has finished.

To finish off this blog on blood and bleeding, the new AAGBI Guidelines on transfusion have just been published, and they replace three previous guidelines on blood component therapy, massive haemorrhage and red cell transfusion. They will appear in the journal next month and will be sent round to every anaesthetic department as well as the Chief Executive of every NHS Trust in the UK. Read them yourself and see if blood really is thicker than water, or at least how important it is in the peri-operative period.



Andrew Klein


Its not what you do it’s the way that you do it.

Anaesthesia Blog, April 2016.

Ella Fitzgerald, Little Richard and Bananarama all famously sang “It ain’t what you do it’s the way that you do it”, and the May edition of the journal reinforces this in several ways.

The first example of this is a fascinating and shocking editorial about sugammadex that has important lessons for all of us who undertake (or take part in) research, audit and service evaluations in our institutions. The authors describe how they determined that a proposed study was a service evaluation and registered their study with their institution, but did not seek formal ethical approval, as advised under recommendations for service evaluations in the NHS, and did not gain patient consent or even discuss participation in the study with their patients. After ENT surgery, they exchanged the tracheal tube for a laryngeal mask, and then administered sugammadex to reverse neuromuscular blockade; the first two patients in their study then developed sudden and dramatic airway obstruction. The study team decided to investigate this further by performing fibreoptic endoscopy through the laryngeal mask on the next three patients and saw that the vocal cords were completely closed following sugammadex administration, a totally unexpected finding that had not been described in the literature before at this point. However, the key point was that they didn’t discuss this and other protocol changes with anyone else, namely their institution or more importantly, the patients themselves. They also didn’t report the adverse events locally. The Editor-in-Chief at the time of submission of the resulting article (Professor Yentis) contacted the authors, and eventually the local ethics committee, and a formal investigation into their ethical conduct resulted. Finally, the patients who took part in the study were contacted, and all agreed that data arising from the study could be published.

There are numerous lessons to learn. What someone thinks is a service evaluation or audit may be much closer to a research study in the opinion of others, and Professor Yentis, in his accompanying commentary, argues that study protocols should be discussed with an ethics committee in many more cases, if not routinely, and prospective patient consent sought. The journal receives numerous submissions where there is doubt about the ethical conduct of the study, and one of the commonest questions I am asked is “Do I need formal ethical permission?” Perhaps the new NHS system of all applications for studies in England (including audits and service evaluations) needing to apply for HRA approval (see http://www.hra.nhs.uk/research-community/applying-for-approvals/) will sort this conundrum out once and for all? From the journal point of view, we expect to change our guidelines to authors and insist that HRA approval has been granted before starting any study from April 2016 – more about this to follow.

What about the actual findings of the work of these authors? Well, these are interesting and quite novel. The adverse effect of sugammadex, namely that it may lead to airway obstruction if given to patients who do not have a tracheal tube in situ, due to vocal cord closure, is important and should be communicated to the anaesthetic community who have started to embrace sugammadex into their more mainstream practice recently, hence the decision to publish the account of this study as an editorial. The way the authors conducted the study may have been flawed, without formal ethical approval or patient consent, but the lessons from their conduct and work still need to be learnt.


There has been much debate in the literature about anaesthetic technique for surgery following fractured neck of femur, between general and spinal anaesthetics (with or without nerve blocks). An excellent article, which analysed the data from over 16,000 operations carried out in 2013 as part of the Anaesthesia Sprint Audit of Practice (ASAP-1), is published in this month’s journal. The overall message I took from this article was that the type of anaesthetic technique (GA or spinal) did not affect mortality, but how, and with what degree of care, especially with regards to blood pressure, the anaesthetic was provided, did matter. On one hand, this is not that surprising – we know that anaesthesia is a craft specialty, and how you give an anaesthetic is important, as demonstrated so eloquently in this article. On the other hand, the lack of a difference between the two major choices of technique (at least with respect to mortality), is surprising, as so many anaesthetists have polarised views one way or another. The question about whether the study design may have affected the findings is also an important one, as discussed in the accompanying editorial. The argument over the relative advantages and disadvantages between large observational studies, such as ASAP-1, and randomised controlled trials (the current so-called gold standard for level of evidence) will no doubt rage on, but in the meantime, the evidence we have is that conduct of anaesthesia is more important than actual technique with regards to mortality after fracture neck of femur. In other words, how you give your anaesthetic, not what anaesthetic you give.

Finally, the first guidelines for safe vascular access are published in May’s edition of the journal. This lists some very important recommendations that I believe will shape our practice with regards to vascular access for years to come. Vascular access, be it peripheral, central or arterial, is the most common invasive procedure carried out in hospitals, and if carried out with care and attention, and with meticulous aftercare, is safe. These guidelines recommend more widespread/earlier use of ultrasound, more formal training and supervision, better systems (including specific policies regarding safety and proficiency), all with the aim of improving safety, effectiveness and timeliness of all vascular access. Remember, it’s the way that you do it (and look after it, in this case), that’s important.



Andrew Klein


The first Anaesthesia blog – April edition

This is the first Anaesthesia Blog, which will mostly talk about the new April edition of the journal. The reason for the discrepancy in months is that the following month’s edition is published online two weeks or so before it is posted out to AAGBI members and print journal subscribers. The idea of the new journal Blog is to direct you to interesting, topical or controversial articles, editorials, reviews, guidelines and letters.

Deciding what to read as a clinician is increasingly hard, as more and more journals seem to spring up each month, and thousands of anaesthetic, intensive care, pain or peri-operative medicine articles are published each year, seemingly continuously. Each journal needs a raison d’être, and ours is to publish clinically relevant, important and novel literature. As a UK-based journal, we have traditionally published a lot of papers from the UK, but that is changing, as more and more submissions arrive from upcoming powerhouses in the research world like China and Korea. Despite all the changes over the last few years, we strive to improve our standards year by year, and to be the best most clinically relevant journal out there.

The new April edition of the journal focuses on a number of sub-specialist areas, but also contains a review of capnography for sedation, which is likely to be relevant to all anaesthetists. The authors, having examined six trials containing 2524 participants, concluded that the use of capnography reduced hypoxaemic episodes. However, they also commented that the quality of the evidence was poor and that this was an area ripe for future research, which was re-iterated by Professor Cook in his accompanying editorial. This discusses what progress has been made towards much more widespread use of capnography outside of the operating theatre. I have certainly noticed that capnography is now routinely used in the ICU and during recovery from anaesthesia, and also for transferring patients around the hospital, but it is yet to be used more widely for sedation, and I agree that further evaluation for such use is urgently required.

Regional anaesthesia is a burgeoning sub-specialty of our practice, and there are a number of innovative and important articles in this issue. The first reports on 1505 patients who received continuous interscalene analgesia at home via a ultrasound-guided catheter. The authors managed to get around the myriad of logistical and safety concerns related to ambulatory administration of the block, and the catheters themselves were taken out by the patients. They reported that 27% of patients reported mild dyspnoea, 13% hoarseness and 7% dysphagia. Twelve percent sought medical advice and 2% reported technical issues with the pump or tubing. The relevance of the excellent large series to practice in other institutions and healthcare settings are described in an accompanying editorial, aptly entitled interscalene catheters – should we give them the cold shoulder? Finally, the use of dexamethasone, either intravenously or added to the local anaesthetic mixture, is examined in a randomised controlled trial of interscalene blocks. The authors concluded that giving dexamethasone intravenously at a dose of 8mg was just as good as giving it perineurally, and probably safer.

Pain relief in the emergency or trauma setting is a controversial subject, and an age-old anaesthetic drug in a new formulation, methoxyflurane, was tested in patients having burns dressings changed. The authors reported a 97% success rate of methoxyflurane analgesia to facilitate these procedures, but noted that limitations included maximal daily and weekly doses, and uncertainty regarding safety in patients with pre-existing renal disease.

The final review I am going to mention concerns radiation safety, which examined a number of studies that showed that at 1.5 m from the source of radiation, anaesthetists received almost no radiation, and that the radiation doses at this distance were often at the limits of the sensitivity of the measuring dosimeter. Does that mean we can take our leads off in theatre as long as we sit more than 1.5m away? I can’t see that happening but in an evidence-based environment perhaps it should?

Teamwork and communication are both buzzwords for all peri-operative physicians, and of vital importance to our everyday practice. Examining different ways of communicating and evaluating their effectiveness is quite a new area of research, and we are seeing more and more submissions to the journal about this subject. This month sees the publication of an excellent study that examined the use of cognitive aids during a simulated intra-operative emergency (anaphylaxis). Team performance was improved by the use of a cognitive aid, and a linear type of aid had the greatest effect. This study should help the design of future cognitive aids, be they on paper or on our smartphones or other innovative technology, and the study methodology was very well-planned and executed to allow the authors to answer their questions about how teams work best.

My final word is a look into what is coming up in the journal. Next month we will feature a lesson in the ethics of clinical trials, which makes scary reading and should prompt us all to re-examine how we categorise research, audits and service evaluations, a thorny issue. Next month will also see the publication of a trial comparing patient-administered with nurse-administered oral analgesia after caesarean section, which could mean the end of the drug round. In April, we will be holding our first Twitter-moderated ‘Chat’ about an interesting new article on analgesia for patients carried on emergency medical evacuation helicopters.

Andrew Klein, Editor-in-Chief, Anaesthesia