Another quick one today.

Was asked recently to fill a teaching slot for the new junior docs in our department, and rather than go with something clinical straight off the bat, I thought I’d have a go at getting them thinking like an ED doc (or to quote my usual phrase “let’s put your ED hat on”). It’s another Prezi, so have 12.5mg of IM procholerperazine at the ready as we answer the question:

WHY ED DOCS ARE BACKWARDS

I would be remiss if I didn’t acknowledge this brillant screencast from Reuben Strayer as inspiration. Essential viewing for anyone working in or about to start working in the ED.

Gareth

P.S apologies to all trying to view on ipad/iphone (especially you @n_may), can’t seem to get this to work yet. If anyone more technically minded has a solution please get in touch!

It’s been quiet in DrGDH land for a bit, apologies for that. As well as battling through the comedy/tragedy/sheer bedlam that is EM in the holiday season (nights over Xmas, thanks boss…), I’ve been applying for a new job while simultaneously trying to keep the one I’ve got, been struck down by Norovirus (that other holiday favourite), and even written a couple of posts over at StEmlyns.

After several requests to ‘summarise’ the reasons I’m sceptical about stroke thrombolysis (I suspect in an attempt to stop me going on and on about it…), I’ve put together this whistle stop tour of the evidence. Just the important points are summarised. For more coherent and detailed analysis I would suggest Andy Neil‘s epic treatise and the phenomenal podcast from SMART EM. Also have a look at this piece by Michelle Johnston looking at the difficulties of being a front-line ED doc expected to provide a therapy we are not convinced is beneficial.

Here we go…. works best full screen.

As always comments, criticisms welcome. Think I’m being too critical? Disagree with my interpretation? You know where to find me….

Gareth

If you read this blog, I’m sure you are also reading the amazing St Emlyn’s blog as well. If not, get over there ASAP!

Shameless self promotion alert: We have only just gone and hit the top spot on the LITFL review! @EMManchester ‘s plot for world domination continues apace….

I am honoured to be part of the team for St Emlyn’s, and as such have started posting over there.

I am reluctant to abandon this blog though, and have a few ideas for it circulating – stuff that is a too frivolous, controversial etc. for the respectable physicians over at St Emlyn’s.

Watch this space.

In the mean time,  here is a quick presentation I prepared for a recent teaching session. Can we really cause brain herniation with a LP needle? Do we need to CT everyone first?

(I make no apologies for the unpolished nature of this stuff, it may or may not have been prepared at the last minute/in front of the new series of Homeland/while holding the baby)

Cheers all,

Gareth

References:

Why does tonsillar herniation not occur in idiopathic intracranial hypertension? Salman M. 1999

Computed tomography before lumbar puncture in acute meningitis: a review of the risks and benefits. Archer BD. 1993

Cerebral Herniation during bacterial meningitis in children. Rennick et al. 1993

Cranial computed tomography before lumbar puncture: a prospective clinical evaluation. Gopal et al. 1999

Would be wrong not to credit Dr Scott Weingart of EMCRIT fame, who’s Crashing Patient website as a much more detailed review of the whole subject.

NICE have recently published new guidance on Upper GI bleeding.

It is surprisingly sensible. I was pleased with their position on PPI’s for upper GI bleeding (not before endoscopy…).

The other point that I was happy to see was the inclusion of the Blatchford score for risk assement of these patients.

We all love a good scoring system, especially if really complicated (long hours spent working out APACHE scores on ICU spring to mind)

The Blatchford score however, is simple, and useful. I have been using this to help plan management of these patients for a while, and I was surprised to find that many people have not heard of it.

So what else to do? To the Bat Cave St Emlyn’s!

What is it?

To give it its full name; The Glasgow Blatchford Score was derived in 2000. It is designed to identify patients who require admission for treatment of their UGI bleed, and who can go home for outpatient management.

Previous to this, standard practice was to admit the mass majority of these patients, even the young well ones with minor bleeding or ‘coffee ground’vomits.

Here it is:

It can be easily calcualted using information availble in the ED. You can use the ever useful mdcalc.com

So why use it? 

So we can send people home! This has to be a good thing, as long as it is ‘safe’ to do so.

In 2009 Stanley et al performed a prospective study to establish whether this was the case. Their hypothesis: If the GB score was 0, the patient could go home from the ED, and be followed up as an outpatient.

Sounds great right? Did it work?

The study was split into two parts. First they collected data on all GI bleeds seen in the ED. They recorded the outcomes, and compared the outcomes with the GB score on admission. In the second part they introduced the low risk criteria, and discharged those with a GB score of 0.

So….

In the first part they identified 334 patients with UGI bleed. 319 of them got admitted (96%)

53 of them were low risk (GBS 0). 50 of these were admitted. None of them died or needed any interventions.

So far so good yes? If we could have have sent those patients home, wouldn’t everyone be happier and the world a better place?

So that’s what they did. In the second phase of the study they put their theory in practice. They identified 491 UGI bleed patients. 123 (22%) of them presented with a GBS score of 0, and of this group, 84 got sent home (68%).

They then followed them up to see how they got on. Only 23 (40%) turned up for their outpatient endoscopy, the rest were chased up via GP, case note review and telephone follow up.

So how did they do? Really well as it turns out. Out of the 123 patients with a GBS score of 0 a total of 0 needed an intervention or died from a UGI bleed related cause in the following 6 months. Zero, zilch, nada.

These results are summarised here:

For those concerned with our limited health resources (i.e. all of us), the exciting figure is at the bottom. Before the scoring system was introduced, only 4% of the UGI bleed patients were being discharged from the ED. With the scoring system in place, 29% were sent home.

Considering the numbers of these patients we all see, this is a big deal.

So should we do this? I think so.

Gareth.

              Maybe they’re small, and just getting the hang of this walking business ….                                         

…. or maybe they’re old enough to start doing daft stuff like this:

That top heavy head on top of an overexcited child seems very prone to getting bashed. Frequently, this means a trip to the ED.

Now most of the time, they’re fine. We know they’re fine after 5 seconds with the child.

After watching them tear around the waiting room  for 3 hours and wolf down the chips and gravy from the hospital canteen, even the parents are starting to suspect the child is fine.

Unfortunately there is another thing kids do a lot of, which can make things a little more complicated:

(couldn’t find a picture of mine being sick)

Now, kids vomit. A lot. They vomit cause they’ve got cold. They vomit cause they’ve got a stomach bug. Sometimes they vomit just cause they’re upset and we look at them the wrong way.

Unfortunately they also vomit if they’ve got a brain injury:

The trick is to work out which ones are puking cause they’ve got a serious injury, and which one are just puking. Which children should we be sending to CT?

We can’t scan all of them. CT scans are not good for growing brains. There are small, but real risks with bombarding your child with radiation, (not just transforming them into a gamma ray fuelled super hero, which some may see as a plus)

There is a suggestion that CT scans as a child can worsen your performance at school , and, most importantly, increase your risk of cancer in later life.

Children also wriggle, and cry, and many of them will need sedation for a scan. This carries some risks of its own.

 So how do we decide who gets scanned?

We are all familiar with one of the well know guidelines (for a brilliant summary of the literature and the guidance out there, try the excellent empem.org podcast). This EMJ article from earlier this year compares the three main decision rules.

Here in the UK, we have NICE guidance. I’m not going to go through it in detail, but with regards to vomiting they state:

“If 3 or more discrete episodes of vomiting….. request CT scan immediately”

Simple enough, clear unambigious (once you tease out the whole ‘discrete vomits’ thing) advice.

The only thing is….

We don’t do it. I don’t do this. My consultants don’t do this. I get the impression from the interweb that a lot of people don’t do this. We seem very happy to observe these children and see how they do, rather than scan them straight away as NICE would recommend.

This option is even written into local guidance. The relavent bit of protocol from Royal Manchester Childrens Hospital goes like this:

You can see, there is that all important phrase. For the children you are at ‘not low’ risk (this includes the vomiting ones), there is provision for a ‘period of observation’ instead of immediate CT scan.

How do we justify this, when the guidance from NICE is clear?

Lets take a closer look:

CHUNDERING IN CHALICE

The guidance from NICE is almost entirely based on the  CHALICE study, which was done right here in my own stomping grounds; the North West of England. If we look specifically at the vomiting kids we see that:

Out of a population of 22772 children (<16yrs, all head injuries included)

857 vomited more than 3 times (3.8%)

56 of these children had a significant brain injury on CT. 801 did not.

Using vomiting as a screening test, and significant brain injury as our disease, we can plug these numbers into a 2×2 table.

It is the positive predictive value that we are most interested in. If a child vomits 3 or more times after their head injury, then their risk of a significant brain injury is 6.5%.

This is a fairly significant number. So why aren’t we scanning all these children then?

There are some caveats to this. The first is that the available data in the CHALICE study does not detail how many of these children were vomiting but had no other risk factors, it is the isolated vomiters that we are interested in.

CHALICE was intended to identify a low risk group we could safely not scan. It was not designed to inform management for those designated ‘high risk’

So on we go. Where else could we go looking? Surely there couldn’t be another massive cohort of head injured children we could examine?

PUKING UP PECARN

We all love PECARN. Their head injury rule was derived from a cohort of 42412 (!). I especially love the fact the low risk group has a lower risk of clinically significant head injury than CT induced malignancy. That’s the kind of reassuring fact you can use.

This massive cohort was comprised of children who had sustained a head injury. Only those with a GCS of 14-15 on presentation were included in the analysis (unlike CHALICE who included everybody).

But what does it have to say about vomiting children?

Interestingly, they do not consider vomiting a risk factor in small children (<2 yrs). It just does not come up in their rule (pathway A on the chart)

In bigger children (>2 yrs) it is included. They consider a history of any vomiting a risk factor, and isolated vomiting puts a child in their ‘intermediate’ risk category. They recommend observation or CT depending on the opinion of the doctor.

Sounds familar right? But what are the numbers? For children over 2 years of age who vomit more than twice, what is the risk of significant TBI?

Without going through it all again, the PPV is low at 2.3%. Low, but low enough to reassure us? Maybe not.

Once again, from the article it is not possible to work out how many of these kids had vomiting as their only symptom.

Fortunately, this time, someone has done it for us. This abstract (page S175) was published by the same team at the SAEM annual meeting 2008. They looked at the PECARN cohort and identified 1228 children with vomiting as their only symptom. Of this group, only one child required neurosurgical intervention, 0.1%. Reassuring, even if it comes from a conference abstract.

CATCH

(running out of vomit slang now..)

Derived in 2010 by Osmond et al (and a lot of the same people as the Ottawa rules), the CATCH rule is another go and deriving a decision rule to help guide our management of head injured kids. A cohort of 3866 kids were looked at from 10 different centres. They included only symptomatic head injuries, so not the really trivial stuff.

So what did they think about vomiting? It got looked at, but didn’t make it into the decision rule:

Once again, it’s not possible from the initial paper to work out which of these kids had isolated vomiting.

But once again, they have asked themselves the same question. The very next abstract (S176) after the one mentioned above looks at the CATCH cohort.

In this group there were 3866 kids.

226 had vomiting >2 times as their only symptom

2 of them had positive findings on CT

0 needed neurosurgery.

Reassuring stuff!

SUMMING UP….

Don’t know about you, but I’m reassured. Although vomiting is mentioned in two of the 3 major decision rules, it looks like that when its an isolated finding, we can be reassured. My practice is to observe these children, and I’m happy I can back that up if challenged.

Despite this, I’m still technically not following our national guidance. In view of what we have found…. time for an update?

Its all well and good if you can observe these children yourself, but in most hospitals these children we need to go to inpatient paediatrics. From my own experience, persuading the paediatricians that a immediate scan is not required can be tricky. I can quote PECARN and CATCH at them until I go blue in the face, but the fact remains that NICE says we should be scanning these kids.

There are more questions to answer here. More evidence needed! The  rules above identify our low risk children, but don’t give us any guidance on what to do with those who are not low risk.

Which symptoms are more predictive of injury than others? For example, it has been shown that if the only high risk feature is the mechanism of injury, then the chance of having a serious injury is low. What about the other symptoms and signs?

If I’m observing them… what then? How long do I need to keep them until the risk of deterioation is acceptable? How many vomits? If not 3, then 5? 10? Or can I happily watch them puking away for days as long as no other symptoms develop?

Answers on a post card please, preferably backed up by a big prospectively identified cohort….

All very exciting!

Am feeling somewhat out of place though, they’ve got famous names, professors, highly published academics, globe trotting adventuring EM docs.

At least I’ve got my little red doctor with googly eyes….

Seriously though, its a great honour, and about time we Brits started to show our face a bit more in the EM internet world! Can’t let the Aussies have all the fun as well as the weather.

More soon!

Gareth

What could be getting be so confused you ask? I’ll tell you.

IST-3

I’d been looking forward to this trial (as much as one can look forward to a piece of research….). It was supposed to make things clear. Is stroke thrombolysis really as good as neurologists keep telling me? Is it really OK in an 85 yr old? Is it really OK to give at 4.5 hrs? A 3000 patient RCT, comparing stroke patients given rT-PA to a control group will answer all my questions.

It was supposed to be great.

Imagine my delight when, on skipping straight to the conclusion I read

“thrombolysis improved functional outcome“

and

“benefit did not seem to be diminished in elderly patients“

Great!

I should have stopped there, I could have gone away happy then, prescribing powerful thrombolytics to all and sundry. But, a nagging sense of responsibility remained, and, against my better judgement, I sat and read the rest of the paper.

I was pleased to see the treatment and control cohorts were well matched; a common complaint about some of the previous stroke thrombolysis literature is that more severe strokes were going in the control groups.

It was on reading through the method I began to have doubts. Non blinded?

The patient selection confused me somewhat as well.

If the admitting doctor really wanted to give the patient thrombolysis, then they did, and the patients was excluded. if they really didn’t want to, then they didn’t get it, and the patient was excluded. The patients in the trial were those for who thrombolysis was “promising but unproven”.

Patients selected for the trial because they were “promising” ?? My resolve was shaken, but OK, they were looking at patients who fell outside the ‘accepted’ indications.

I read on. Surely it would all become clear?

Th outcome measures were reassuring. A nice solid primary outcome: the number of patients alive and independent at 6 months.

The trial finished with 3035 patients. They didn’t reach their goal of 6000 patients, but compared to other stroke thrombolysis trials, this is huge. I was encouraged.

On to the results then. I had read the conclusion already so knew what to expect.

Of 1515 patients who got thrombolysis 554 (36.5%) were independent at 6 months. Of 1520 controls, 534 (35.1%) were independent at 6 months.

This didn’t seem right…. a 1.4% difference doesn’t seem like much at all.

And there it was: p = 0.181.

There was no significant difference in the primary outcome.

A sense of self doubt set in, what was I missing? How do the authors go from that to “thrombolysis improved functional outcome”. A search through the text provides a possible explanation

“A secondary ordinal analysis provided evidence of a favourable shift in the distribution of OHS scores at 6 months with treatment“.

Further self doubt, I don’t know what a ‘secondary ordinal analysis’ is. A nagging thought occurs…. this sounds like statistical voodoo to me….

Having found no answers in the paper itself I took to the Internet. Surely someone in the blogotwittersphereverse as an explanation?!

However, it seems that everyone else is as baffled as I am. Even the great Dr Newman of the NNT.com could not explain it, concluding that the authors have gone “stark raving mad” and their conclusion is “delusional” . Other trusted sources are similarly unimpressed; EM literature of Note and Emergency Medicine Ireland both conclude it is a negative trial.

So no answers there then. How this trial can be considered positive, when it is negative for its primary outcome? Are we to agree with Dr Newmans conclusion and question the sanity of the authors?

I hope not. Surely there must be someone out there who can explain this to a confused ED Doc? Answers on a post card please…. or failing that, comment below.

Until then, I’m going to struggle to factor IST-3 into my ‘informed consent’ spiel…….

Posted with Blogsy

Hopefully, many of you will have read my post from last year on fascia iliaca blocks for fractured neck of femur patients, it certainly has been one of the most popular posts I’ve written. I think these blocks were great, love doing them, and I make no apologies for my enthusiasm for this procedure.

However, I have discovered two docs from the USA whose love for all things ultrasound eclipses even mine. I’m talking of course about the Ultrasound Podcast guys. If you haven’t seen their videos yet, I can’t recommend them highly enough.

I loved their latest post on femoral nerve blockade, and wanted to talk about it quickly here. The technique they describe is different to the one I have been using; but it’s explained with such clarity and enthusiasm that I immediately wanted to go and try it out.

They describe using an in plane approach, with the probe positioned across the inguinal ligament to give us that familiar N-A-V view. They then introduce the needle in plane with the probe from the lateral aspect, aiming to place the local under the fascia ilaca, as close to the femoral nerve as possible. If I’m not making it very clear here, go and watch the video!

I can see two advantages to this approach.

Firstly, the needle is in plane with the ultrasound beam, and introduced at a much shallower angle, making it easier to keep that all important sharp end of the needle in view.

Also, this approach means you can place the local right next to the nerve. The podcast suggests that this means you don’t need the large volume we are used to using for this block.

Sounds great doesn’t it? I can’t wait to try this out. Many thanks to the Ultrasound Podcast guys for all the great work they do!

Typical conversation during a shift the other day. SHO presents a case, and asks if she can send a patient home. We have a quick chat about the options and follow up arrangements and agree to discharge. As she leaves to sort everything out she volunteers that I “make her anxious” about discharging patients.

“How come?” I ask, puzzled. I always make a point of going through these conversations carefully, so we can all be confident that we are doing the right thing; surely that’s me just being reassuring?”You always tell me all the worst things that could go wrong” she replies “and then we send them home anyway!”

This got me to thinking – am I a cause of SHO anxiety? Could our high sickness rate amongst the juniors be down to DrGDH induced stress? (rather than ‘lack of moral fibre’ as one of my colleagues has suggested)

OK, I’ll admit, I do have an annoying habit a quoting statisitics at them. I’m always keen to remind them that this patient they were happily discharging could potentially come to some catastrophic misfortune after leaving the hospital.

Why do this? Is it purely cause I enjoy messing with their heads? Maybe a little. But I would like to think that I have a educational goal in mind as well.

Risk adverse? Look away now

Discharging patients is fraught with risk, and not just because ‘the patient might get run over in the car park’. I do (or I like to think I do) careful, evidence based work ups for patients everyday, and still send them in the full knowledge that a small number of them will come to harm. This applies to some of the most common presentations in the ED:

Have you ruled out ACS? Even the low risk, patient with atypical chest pain, who’s cardiac enzymes and ECG you have carefully scrutinised isn’t safe. Around 1 in 117 of them will suffer some serious cardiac mischief.

How about PE? Got 257 low risk, negative d-dimered patients? One of them is going to have a PE. How about those positive d-dimers that have a negative CTPA? 1 in 205 of them will have a fatal PE….

That collapse episode you have confidentaly diagnosed as a ‘faint’ and are keen to send home? The 7 day mortality is 1 in 250.

Now all those figures are generalisations, and based on large cohorts, so they can’t be applied to individual patients. But you get the idea.

The world is not a safe place, and especially if you are in a population who attends an ED. There is always risk in discharging patients, but we cannot, and indeed should not, eliminate all risk. If we attempt to do this, we are potentially putting the patient in danger, and are acting irresponsibly with limited health resources.

Test thresholds, and the risks of not discharging your patient

My favourite example of this is wonderfully explained by the legendary Dr David Newman in the Smart EM podcast on PE. The concept of a test threshold is a vital one. The idea is that some patients have such a low level of risk, below which the risk of further investigation is greater than the risk of the pathology we were diligently searching for.

This is a simple concept, and one which we all intuitively understand. The alternatives to discharging patients: lying in a hospital bed, investigations, treatments are all things that carry risk, and we do not want to expose patients to this if this risk is greater than the one we were trying to eliminate.

Do patients want to know this? Should we tell them?

Accepting and embracing this idea is central to Emergency Medicine, we manage risk every day as part of our decision making. Patients however, do not make this decisions every day, and may have some stong opinions where their health is concerned. I still have not found my comfort zone when deciding how much we should be including patients in this process. While it sounds appealing in this age of doctor-patient partnerships, it still makes me uneasy.

Recently I observed a stroke physician counselling a family on the risk/benefit of stroke thrombolysis. He carefully explained the pros and cons, gave figures to illustrate the potential harms and benefits, and then asked “do you want us to give this medicine?” Informed decision making at its finest surely? I’m not so sure. I like to think that I have a reasonable grasp of the literature in this area, and I’m not sure I could make a informed decision, let alone about a family member in a high stess situation.

Or how about our low risk cardiac patient above? Am I to explain to this fit and well 62yr old man that his heart trace and blood tests are normal and I am happy to discharge him home…. but the research says that he has a 1/117 chance of going on to have a heart attack?

Some would argue that it would empower him to make an informed decision, but what other options do I have? Do you think in the NHS I could admit this man to cardiology because he is not happy with that risk? I’m not sure I could if I wanted to. Do you think that admission and investigation may carry a greater risk than 1/117? It’s possible.

Take a breath…..

Plenty for me to think about. So am I going to continue to freak out my juniors with this information? Definitely, because this concept is a vital one. We cannot, and should not, attempt to eliminate risk. Therefore we have to be comfortable accepting a certain level of uncertainty. Nowhere else is this choice more stark than in EM or primary care, but the concept applies to all of medicine. Do we want to treat the patient, or treat our own unwillingness to embrace risk?

Thank you for reading. I would be delighted to hear what you think about all of this. How do others practice when it comes to explaining risk to patients? Comments/tweets/abuse gratefully received.

Addendum

Thanks to EMUpdates for putting the reality of risk management in one line:

“However, Uncertainty is the currency of emergency medicine. We have to make important decisions with very little information. We are wrong a lot. Sometimes, when we’re wrong, people die. Learning to be comfortable with uncertainty is difficult.”

Meningitis is one of those ‘don’t miss’ diagnoses that we as emergency docs get hung up on. Personally I have a low threshold for administering emperical antibiotics and starting the work up. Antibiotics are the key, the right ones and sooner the better. This chap got antibiotics before the lumbar puncture to prevent a delay waiting for CT (but this is not always necessary). As for which antibiotics: Where I work ceftriaxone is the 1st line; it is sufficient to cover all the potential nasties. We would also add amoxicillin in patients considered at risk of listeria meningitis. Traditionally this would include the young, the old and the immuocompromised. I did not give empirical amoxicillin here, as he did not seem to be at risk.
Unfortunately the next few days did not go well for our patient. His renal function deteriorated and he required haemofiltration. On the third day microbiology called to tell us a gram positive cocci had been grown in the CSF sample. This was subsequently confirmed as Listeria Monocytogenes.

This was a surprise, and also a worry. He was switched to high dose amoxicillin but we had been without definitive therapy for his meningitis for 3 days, and was extremely ill.

Ensuring the correct empirical antibiotics are given is even more important with Listeria Monocytogenes, as it can be difficult to identifiy early on. For our chap, if the gram stain had suggested a gram postive cocci on admission, then we would probably have covered him for Listeria straight away. Listeria can be difficult to pick up on a gram stain however – a large retrospective review of Listera CNS infections by Mylonakis found initial gram stain was negative in two thirds of patients.