Understanding Troponin Part 1. St.Emlyn’s

Do you remember when it took three days to 'rule in' or 'rule out' an acute myocardial infarction (AMI)?  When I was a medical student doing my first clinical attachments, I remember doing ward rounds on the CCU seeing patients with suspected AMI.  The way they were managed is a million miles from what we do now.  Back then, patients would have serial ECGs and then be admitted for cardiac enzyme evaluation over the course of the next 3 days.  We'd measure CK, AST and LDH.  'CK' was the so-called 'early marker', which would rise early after the start of an AMI.  Today we use CK as a marker of skeletal muscle damage (e.g. rhabdomyolysis).  AST and LDH (today we think of these as liver function tests, I know) were the 'late markers' - and by late I really mean late - we might see a rise on days 2 and 3.

Could you imagine for a second, in today's world, ruling out AMI because their CK and LFTs were normal?  It's completely unthinkable.  That's how much cardiac troponin has changed our practice.  We rely on it so completely to diagnose AMI.  And yet, it's one of the most misunderstood tests in medicine.  Given how much we use it, I guess we feel that we all should know lots about this test.  But doctors still have so many questions.  Here are just a few:

• What is cardiac troponin?
• Why is it a marker of AMI?
• What else causes a raised troponin and how?
• Should we be doing troponins at 3 hours, 6 hours, 12 hours?  What's the difference and what's the evidence?
• What is a 'delta troponin'?
• What do you need to 'rule in' AMI?
• How do you use cardiac troponin in patients with renal failure?

This is just a brief list.  With the research I do in this area and my experience developing protocols/guidelines, people get in touch to ask questions like this quite a lot.  There are loads of questions that people ask - but there are lots of themes in common.  We thought it was about time we produced a handy run down in the true spirit of #FOAMed.

Take a listen to Part 1 of our troponin podcast.  While Simon and Iain have been prolifically churning out spectacular stuff for some time now, this is my debut on the St. Emlyn's podcast.  I really enjoyed talking about troponin with Iain - and I hope we covered some useful stuff.

We'll cover more in part 2, when we'll move on to discussing high sensitivity troponins, what they are, how to use them and how to speak the troponin lingo.  Please get in touch if there's anything we haven't covered that you'd like us to, or if there's anything you'd like us to elaborate on some more!

Rick

Induction to EM. Staying safe in your first job. St.Emlyn’s

If you're starting out in EM then it can be a scary time. Iain and Simon talk through some of the initial anxieties and ask what you need to know to be safe, sensible and super.

Archery in the ED. What can we do about targets? St.Emlyn’s

It is a little known fact that to be successful as an emergency physician in the UK it is vital to take a three month rotation in Archery. Archery is a key skill for us all dating back to Medieval times when we introduced the longbow into warfare. This devastating tool could cause panic in opposing forces, scattering them into many wide and ineffective directions. In short they were an effective tool to cause and disruption inthe opposition ranks whilst the noble English armies of old strode forward with their visions of the future. Soldiers trained using targets to hone their skills and to focus on the aim - meeting the target.

Of course these days we do not have real bows and arrows in the emergency department, but archery remains alive and well. In the modern NHS we still train our troops in archery, or at least in the principle aim of archery - to meet the target.

With our long history of target setting and target hitting it is therefore no suprise that we are world leaders in standards/targets/indicators....., whichever term you prefer in fact and it has to be said that a target culture in the NHS has been criticised widely, even being blamed for the exodus of trainees to Southern climes, but there is arguably more to it than that.

In last weeks episode we touched on new targets around trauma care in the UK and that raised many questions and opened a debate on twitter. This week we want to take those thoughts further and ask what we, as the archiest of arch archers across the entire NHS can do with these externally set targets.

What we forgot to say in the podcast is the absolute need to work alongside a short stay admissions unit under the ED umbrella. Without that you would really struggle to deliver safe and efficient care. We both work in units with short stay admission units that allow us to deliver safe diagnostic and therapeutic interventions to our patients.

So, with some trepidation Iain and I ask whether all targets are a bad thing....

vb

S

Trauma Team Leadership - the 30min CT target. St.Emlyn’s

Iain and Simon discuss the challenges of getting our trauma patients to the CT scanner within 30 minutes of arrival.

The 30 minute target is a UK standard, and we did not set it! All UK trauma centres are judged against the target and (rightly or wrongly) it has become a real issue for many centres.

We would be really be interested in what our International colleagues think about the target and the resultant strategies outlined by the team. There's more on this at the St.Emlyn's website.

As always, we'd love to hear your comments.

vb

S