All posts by Simon Carley

Professor Simon Carley is Consultant in Emergency Medicine. He works in adult and paediatric emergency medicine. He has published over 100 academic papers and has a passion for research and education. He strongly supports Meducation and #FOAMed. He co-developed BestBets, the virtual hospital at StEmlyns and the stemlynsblog He is co lead for the MSc in Emergency Medicine at Manchester Metropolitan University. + Simon Carley

RIP Dr. John J Hinds

#DeathIsAWanker-3St.Emlyn’s loves you John.

Thanks for being awesome and for sharing so much.

We will miss you terribly.

St.Emlyn’s

 

Please pass on your thoughts to the family via Rob Mac Sweeney (see below)

Great thoughts

Links to some of the great work John was involved with

And of course

#smaccUS day 1. A bountiful cornucopia of Medutainment.

Screenshot 2015-04-16 10.12.21

Day one at #smaccUS did not disappoint. An amazing musical start to the day followed by an intense plenary session with some of the luminaries of the #FOAMed movement.

The five concurrent sessions were a real challenge for the team. Where to go and what to see. A bountiful cornucopia of medutainment across a range of subjects.

Don’t forget to check out the workshop podcast here.

You can also check the thoughts of our friends from Birmingham on the HEFT cast here.

Catch up with what the St.Emlyn’s team learned on the podcast.

Before you go please don’t forget to…

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#smaccUS day 0 – the workshops. St.Emlyn’s

SmaccChicagoLogo

The St.Emlyn’s team (well some of them) are currently at the greatest conference in the world. If you don’t know about Social Media and Critical Care Conference then seriously you must have been living under a rock.

This week we will be podasting, tweeting and blogging daily so keep an eye on our twitter feeds, follow the blog and subscribe to us on iTunes.

To kick us off let’s hear about the fabulous workshops on day 0……

Then check out day 1 here.

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Simon

 

Before you go please don’t forget to…

JC: Are typical chest pain symptoms predictive of outcome? St.Emlyn’s

Chest pain

We love a bit of meta-cognition here at St.Emlyn’s. As time passes and we all become a little longer in the tooth it becomes increasingly apparent that it’s not just ‘what’ we know it’s how we use it. In diagnostic testing in the ED (something that we are supposed to be awesome at) we must understand how we use tests and how our clinical judgement affects the use and subsequent performance of those tests.

We are always on the look out for papers that examine how we think and how we make decision and so I was intrigued to look at this paper on the ability of clinicians to determine the probability of underlying MI/IHD in patients presenting to the emergency department. If you’re a regular reader you will know that Rick Body has a great deal of experience in this area and has published widely on clinician ability to identify patient risk. You might want to look at these blog posts where we have explored judgement and metacognition in the past.

How good is clinical judgement in assessing chest pain?

Is severe chest pain more likely to be a heart attack?

What is Gestalt?

The paper is from Bristol UK and the abstract is below. At the moment it is open access on the website so please read the abstract, but as always, if you can find the time please read the full paper before going further.

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What kind of paper is this?

This study was part of a larger study at the use of chest pain pathways and high sensitivity troponins. This is a pre-planned study within that larger study and it’s essentially an observational cohort.

Tell me about the patients

They have looked at 912 patients of whom 12.5% had an AMI. This is a fairly low event rate but not dissimilar to other studies in this area as they have only looked at patients with a non diagnostic ECG. Interestingly they excluded patients who had no diagnostic testing which may have missed a small number of patients. The study is looking at judgement and part of that judgement is whether or not to test a chest pain patient for AMI. It’s tricky as the alternative would be to test everyone with chest pain according to predetermined criteria. This way is more pragmatic but it may have missed some patients. This is a single centre UK medium sized hospital, so limited because single site, but not untypical of many UK departments.

What did they do?

In the larger study they are following patients through to a definitive diagnosis of AMI/not AMI and IHD/not IHD using troponin testing and angiography. Since that will give a pretty robust gold standard outcome they have collected data on physician impression of pain as patients presented in the emergency department. They have asked clinicians to state whether the pain is typical or not then followed the patients through to see if they are right. They have also compared experienced vs inexperienced clinicians to see if seniority improves performance.

AMI was determined using the third universal definition of MI and IHD determined in some patients undergoing angiography although that was quite a small percentage (17.2%).

What did they find?

The key findings from the authors are that fewer than half of patients were characterised as having typical chest pain and that experienced clinicians. There was a small difference in classifying patients as ‘typical’ between experienced and non-experienced clinicians (35.2 v 45.8%).

The ROC curves are interesting and reminiscent of work we did on risk factors in cardiac disease. In other words the performance of doctors in assessing risk is rubbish! Hang on though. This is a little bit unusual as chest pain typicality is a dichotomous variable (the chest pain can either be typical or atypical – there are only two possibilities).  You usually use an ROC curve to plot sensitivity versus specificity for something that could have several possible cut-offs (an ordinal or continuous variable).  However, they have plotted a single value on these curves and then drawn lines to the corners.  If you only have one data point then it’s really just a dot and therefore you shouldn’t really use an AUC (Area under the curve) analysis. Have a look at the graphs below for interest, but bear in mind that the most sensible way to look at this data is to consider the specificity of the opinion of the clinician.

It’s also worth asking what we mean by sensitivity in this study. Arguably it’s irrelevant as all patients are at suspected disease (that was one of the inclusion criteria) but in order to plot a ROC curve you need a sensitivity and a specificity so it appears that they have plotted the sensitivity at the point of describing the pain as ‘typical’.

So, the graphs are interesting but I would not focus on them. The key finding is the specificity.

 Discriminatory ability of the typicality of chest pain for either acute myocardial  infarction, or significant coronary artery disease with and without high sensitivity  troponin T elevation.

The authors have looked at experience and in the paper discuss the fact that experienced clinicians have slightly better specificity than non-experienced. In terms of specificity experienced clinicians had a specificity of 65.8% vs non-experienced at 55.4%.  However, I’m not sure how much use that is. This data tells me that they are both rubbish at it. Sorry folks, but I suspect that you are just as poor at determining this as other clinicians around the world (including me). Although there is a difference it’s clinically unimportant and I’m not sure that we can use experience as a determinant of probability in clinical practice.

It’s also interesting to see that 685/912 patients in this study were seen and assessed by doctors with less than 2 years of emergency medicine experience. International readers may find this surprising but it’s typical of many UK EDs and I would argue that in many hospitals the proportion of patients seen by juniors is even higher. On a marginally political note and with no wish to offend any hard working junior docs this study does show that UK EDs have a seniority staffing issue even when assessing chest pain patients who are clearly a high risk group.

So in summary?

The bottom line from me is close to that of the authors. You’re a bit rubbish at determining whether your patient has AMI or IHD on the basis of gestalt, clinical judgement or gut feeling. Don’t guess – test.

 

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Questions for FRCEMers

1. On the ROC curve looking at the diagnosis of Acute Myocardial Infarction place a cross at the point where the test performs best (in statistical terms).

2. If 1000 patients were assessed by senior emergency physicians on the basis of this study and 300 of those patients were selected as having typical pain then how many of the 300 identified as having typical pain would have a final diagnosis of AMI assuming a specificity of 65.8%.

 

Before you go please don’t forget to…

Top 10 Trauma papers 2014-2015. St.Emlyn’s

Screen Shot 2015-04-22 at 21.25.25I was recently at the Trauma Care UK conference in Telford. As ever, it’s a great bunch of people working hard to improve trauma management in the UK.

My talk this year was on the top 10 trauma papers published in the last 12 months. It’s a nice talk to give, largely because it involves presenting other people’s work 😉 , although the trauma literature has been a little lean in the last 12 months. Whilst we have seen some amazing trials in sepsis, there is relatively little to talk about in trauma.

LISTEN to the podcast by clicking on the link below (apologies that the slides are not in the same order as the discussion).

I was lucky enough to team up with Simon Laing from the RCEM FOAMed network to podcast on the top 10. We are jointly publishing this on both sites so please have a listen, follow the references and if you agree or disagree with my opinions please let me know in the comments section, on twitter or on facebook.

So with that in mind, in no particular order and with a selection process entirely based on ‘stuff I like’ here’s the top 10.

Number 1. PROPPR trial

We’ve talked about this on the St.Emlyn’s site already. This is an RCT of 1:1:1 vs. 1:1:2 (platelets/FFP/blood). It’s a well conducted trial relevant to our trauma patients who need blood. The bottom line? Use 1:1:1 it’s statistically just as good, and there is a suggestion that this trial is under-powered to demonstrate superiority of 1:1:1. Read more from Salim at REBEL EM and listen to Ken and Salim discuss it at SGEM.

 Number 2. Progesterone in major head injury

Again a paper we’ve reviewed here at St.Emlyn’s. A well designed RCT that promised much on the management of patients with GCS 4-12 significant head injury. The bottom line? No benefit to progesterone infusions in these patients. So it’s a no to progesterone in the real world despite promising animal data.

Number 3. Fixed dilated pupils in head injury – What’s the prognosis?

Arguably better than you thought! A small systematic review that gives us the real world outcome data for head injured patients with fixed dilated pupils. The headline here is that those with an extradural and fixed dilated pupils have a >50% chance of a good neurological recovery. Please, please, please aggressively manage these patients and avoid any nihilism as a result of this pupilary sign. Don’t forget to sign up to one of the authors, Mark Wilson’s, GoodSAMApp too.

Number 4. How good is REBOA?

There’s lots of interest in REBOA at the moment and I get that. It’s exciting and pathophysiologically it makes sense for patients with exsanguinating lower body bleeding. It’s fairly new to the UK and centres such as London HEMS are instituting it carefully and systematically with good training and audit processes. What of the rest of the world though? Well others, such as the Japanese, have been doing this for some time and in a registry based paper they compared patients receiving REBOA with matched controls who did not. They found a much higher mortality (75%)in those receiving REBOA. There are many reasons why this may be and it’s not reason to NOBOA (get it 😉 but it does mean we need to carefully evaluate how we impliment it, who gets it and what happens to them. If 99% were going to die anyway but by using REBOA the Japanese managed to improve it to 75% that’s a positive result. We just don’t know yet, but we may do soon as the AORTA trial is ongoing in the US. More on REBOA at LITFL,  EMCRIT and RCEMFOAMed.

Number 5. The HIRT trial. An RCT of Physician PHEM for head injured patients.

This trial is worth a read as it’s big, expensive, ambitious and controversial. An RCT of physician staffed helicopter vs. ground paramedics for the treatment of head injured patients in Sydney. The trial reports an improved outcome for GCS<10 patients, no difference for GCS <14. However, lots of controversy and worth reading comments on this from luminaries such as Karel Habig in Sydney, with some real concerns about intention to treat vs. delivered therapies and interventions. You should also read the authors own reflections on prehospital research here. Whatever you make of this study if you are interested in prehospital trauma research it’s well worth reading the paper and all the controversies that surround it.

Number 6. DSI for the hypoxic patient

A bit of a cheeky one this as an observational study on the use of Delayed Sequence Intubation. Sadly only 2 trauma patients in the study so arguably should not be here. However, as a proof of concept for combative, hypoxic patients it may be helpful. More on DSI here. Arguably we’ve been doing it for years but previously never had a name for it…….

Number 7. Gestalt in predicting major bleeding in trauma patients.

When I’m in the resus room as a trauma team leader I often wonder whether or not to activate the major haemorrhage protocol. Sure, for those patients who are hosing blood out of every orifice (new and traditional) then sure it’s easy. Similarly for those patient who are completely fine with no apparent on going bleeding it’s east (don’t do it). However, there are a number of patients that I see where it’s a tough call. I’ve often thought that I’m just not very good at this, I’ve flirted with objective scores and worried that others are better than I. The bottom line is that despite many years of trauma management I still struggle, so I was interested to see this paper on clinician ‘Gestalt’ in the resus room with reference to whether patients need MHPs. The bottom line is that clinicians are poor at deciding which patients are going to require major haemorrhage and so are the objective scores. Gestalt may not be that great. As a Trauma Team Leader this tells me that I must be vigilant and constantly reassess the need for 1:1:1 resuscitation.

Number 8. Standardising drugs for trauma RSI.

I chose this paper as it’s an issue in Virchester. We do a lot of RSI in our resus and it’s noticeable that there is much variation in drug use. In contrast those I really respect as resuscitationists in PHEM have adopted standardised approaches to drug use. KSS looked this and compared an old regime (etomidate plus sux) vs Ket/Fent/Roc and found the latter to give better views and cardiac stability. Although a before/after historical trial it fits with my belief that that Fent/Ket/Roc is a good regime to use as a baseline protocol for trauma (ED) RSI.

Number 9. TXA in severely injured patients.

If you follow St.Emlyn’s you will know that we are big fans of TXA. However, the world (mostly US/Aus) don’t always agree. CRASH-2 was a multicentre, multinational study that involved different types of trauma systems. Some in what they perceive to be ‘advanced’ trauma systems claim that TXA would not work for them. I recently experienced this in the US where this trial (observational crap) was used to refute CRASH-2. Honestly? I don’t get it, but the bottom line is that patients may be losing out across the world as a result of the lac of adoption of TXA.

Number 10. Lastly Thoracotomy in blunt trauma.

I have been taught for many years that there is no role for thoracotomy in blunt trauma. I can remember waiting to receive a patient with pre-alerted traumatic cardiac arrest in Virchester, I’d briefed the team and we were prepped when just before the patient arrived the consultant surgeon burst through the door and immediately shouted to all present ‘The one thing we are not ******** doing is a thoracotomy’. It was an interesting moment…….., and some education took place….. Anyway, it reflects the dogma that there is no role for thoracotomy in blunt trauma, but is that right? Well perhaps not. In this systematic review there are some survivors, albeit just 1.5% neurologically intact. Is that a futile therapy? Perhaps not and if your patient has a potentially survivable injury and arrests in front of you it may be worth a go. The authors outline an algorithm for patient selection. Read more at EMLitofNote.

 

So there you go. Ten papers in a fairly lean year for high quality science, but much to think about and a few that may really change practice in the resus room. As with everything on St.Emlyn’s don’t take my word for it. Follow the links, listen to the podcast, read the papers and make up your own mind :-) .

….and please like us on Facebook 😉

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Before you go please don’t forget to…

 

 

References & Links

1.  Transfusion of Plasma, Platelets, and Red Blood Cells in a 1:1:1 vs a 1:1:2 Ratio and Mortality in Patients With Severe Trauma The PROPPR Randomized Clinical Trial.
JAMA. 2015;313(5):471-482. doi:10.1001/jama.2015.12

2.Very Early Administration of Progesterone for Acute Traumatic Brain Injury. N Engl J Med 2014; 371:2457-2466

3. Prognosis of patients with bilateral fixed dilated pupils secondary to traumatic extradural or subdural haematoma who undergo surgery: a systematic review and meta-analysis. Emerg Med J doi:10.1136/emermed-2014-204260

4. Survival of severe blunt trauma patients treated with resuscitative endovascular balloon occlusion of the aorta compared with propensity score‐adjusted untreated patients. Journal of Trauma and Acute Care Surgery: April 2015 – Volume 78 – Issue 4 – p 721–728 doi: 10.1097/TA.0000000000000578

5. The Head Injury Retrieval Trial (HIRT): a single-centre randomised controlled trial of physician prehospital management of severe blunt head injury compared with management by paramedics only. Emerg Med J doi:10.1136/emermed-2014-204390

6. Delayed Sequence Intubation: A Prospective Observational Study. Ann Emerg Med. 2015 Apr;65(4):349-55.

7. Clinical gestalt and the prediction of massive transfusion after trauma. Injury Volume 46, Issue 5, May 2015, Pages 807–813

8. Significant modification of traditional rapid sequence induction improves safety and effectiveness of pre-hospital trauma anaesthesia. Critical Care 2015, 19:134

9. Tranexamic Acid Use in Severely Injured Civilian Patients and the Effects on Outcomes: A Prospective Cohort Study. Annals of Surgery: February 2015 – Volume 261 – Issue 2 – p 390–394

10. To be blunt: are we wasting our time? Emergency department thoracotomy following blunt trauma: a systematic review and meta-analysis. Ann Emerg Med. 2015 Mar;65(3):297-307.e16