The Procedures Course

This week we got 9 of our consultants through The Procedures Course. Added to the one who had already done it, that is half of our senior staff having done the course now.

There are a lot of useful courses around these days, with higher and higher expectations of acute health care and fewer opportunities to maintain skills in the workplace due to specialization, safer working hours and the expectation that clinicians will not learn something new on a critically ill person without having some sort of qualification or experience in it first.

This course is a bit different from most. While the wonderful world of simulation has brought us the chance to practice many critical cognitive and technical skills in safe environments, the use of cadavers in medical training has really dropped off. In Australia, more than the US, we have a squeamishness about cadaver training. As a medical student I spent several hours a week for the first year and a half on cadaver based anatomy workshops but that is largely gone from modern medical training. Clinical training with cadavers remains quite uncommon here.

Thanks to the enormous generosity of the people who asked to donate their bodies to medical training before they died, and the hard work of the team from the Alfred Emergency and Trauma Centre and Trauma Unit, supported by expert faculty including neurosurgeons, ophthalmologists, obstetricians, orthopods and others, we were able to learn and practice a raft of life, limb and sight saving skills this week. It is hard to describe how much more capable I feel as an emergency physician having done this course, and I’ve been one for a while now!

Check out the course website, not that they need the publicity, they have sold out their next course already.

Hog Fat… Is there anything it cannot do?

I’m showing my age clearly because when I searched for that quote online to get the youtube clip of Homer Simpson uttering the words in wistful admiration of a power station powered by hog fat, it was nowhere to be seen. Now that I think of it, that episode probably predates youtube.

Anyway, down to business.

Khiem Ngo has just joined the Bendigo ED Education team as Co-DEMT. I have him to thank for bringing us this innovation.

When you have eaten all the crispy pork belly you can possibly eat (impossible?) use the left overs to create a peripheral IVC ultrasound phantom that is more realistic than any you will buy commercially.

 

Ingredients

  • Pork belly or waste pig skin (ask your butcher as they will often have some that is destined to be tossed out)
  • Long skinny balloons used for making balloon animals
  • Water

Method

  • Fill balloon with water but don’t distend it. Tie it off.
  • Cut pig skin into strips 4-5 cm wide and 15 cm long (2 inch x 6 inch)
  • Blunt dissect a tract through one of the fascial planes. We used a dilator from an expired pigtail catheter set but you could probably use a biro or pencil
  • Use a pair of long artery forceps to feed your balloon through the tract
  • Massage out any air bubbles along the tract

How much does that scan cost?

When I started out as an EM trainee, having dated a radiographer I was very cognisant of the radiation penalties from medical imaging as well as the associated risks of developing a new malignancy.  Over time my conscientiousness in requesting radiology has waned.

My individual threshold for imaging remains relatively high, especially in circumstances where validated clinical decision instruments determine further work-up to be unnecessary.  Nevertheless, arguing the toss over imaging vs not imaging with other teams (who will likely ultimately be responsible for the patient’s care) becomes intellectually frustrating. It is usually easier to facilitate care by ordering a scan and saving one’s energy for something else. Like stroke care. No wait…. forget that one too.

In equivocal cases, appealing to the attendant radiation penalty of a study may encourage deferment in favour of clinical observation.  I put together this infographic to help facilitate such a conversation, and to help me quantify radiation dose and risk of malignancy in preparation for my fellowship exam.

Another way to look at it: if you’ve spent a metaphorical $20,000 worth of medical radiation you’ve probably given someone cancer. And made a radiologist wealthy. Let’s budget our radiation wisely.

P.S. If you’re prepared to pay with personal time to study and scan, ultrasound is free 🙂

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Promises from #ACEMVIC16

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If you enjoyed my talk in Torquay and you want to know more about #FOAMed and how you could benefit from using Twitter here are some resources that you will find interesting

Enjoy your journey on Twitter and I hope that you find it as fascinating as I have! Feel free to message me if you have any queries about this

@cianmcdermott

 

 

 

Lost dogs and lessons in fluid tolerance

Winter and spring have been unseasonably wet for central Victoria. With plenty of moisture in the soil, things were looking green and gorgeous so when a friend asked me to farm-sit for him I jumped at it. Looking after horses, a moustachioed cat and a beautiful border collie were a small price to pay for enjoying a landscape of granite boulders and grape vines. That was until the dog ran away.

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Dusk arrived and Annie was still missing in action. Terrified by the idea of telling my friend about his lost dog, I decided to chase her down. I had been warned about the risk of getting bogged if I deviated off track…. meh! The ground seemed solid, I had a decent 4wd, and I clearly knew better. Spotlights on and eyes scanning, I started cruising across the paddocks. But pride comes before the fall. It was only when the ute suddenly stopped moving did I appreciate that the ground was less fluid-tolerant than my gestalt told me.  Lost car, lost dog, lost for words (other than 4-letter ones), I tried to make meaning of the day’s events and realised it was a teachable moment in the management of sepsis in the emergency department.

 

 

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When patients arrive in the ED with febrile hypotension, we routinely prescribe in excess of 20-30cc/kg of salt water. The pseudoaxiom is that fluid bolus therapy will improve macrocirculation (arterial blood pressure), and therefore improve microcirculation (tissue perfusion). This is unlikely to be true. Empirically “aggressively resuscitating” people with fluid boluses probably causes harm.  Like the fool in the Hilux chasing the missing dog, we chase haemodynamic targets with unproven watery therapies (or disproven if you’re a marginalised African child) that are physiologically suspect and warrant close examination.

The pathophysiology of sepsis is complicated. The basic mechanisms of the disease, however, (at least as we currently understand it) are less complex:  vasodilation and glycocalyx (GCX) dysfunction. Organ dysfunction in septic shock can largely be attributed to one or both of these mechanisms. It is not due to hypovolaemia.

Currently there are no treatments for GCX stabilisation (unless you are a Scandinavian neonate having open heart surgery in which high doses methyl-prednisolone seems to reduce concentrations of a plasma syndecan-1; an alleged surrogate for GCX dysfunction). Current treatments for vasodilation include noradrenaline, adrenaline,  vasopressin, methylene blue, and angiotensin-2.  In sepsis, fluids cause organ dysfunction through worsening interstitial oedema due to GCX dysfunction, and cause vasodilation by stimulating release of naturetic peptides. It is therefore bizarre that it should be used as a first line therapy for septic shock.

Pseudoaxiom one: Fill the tank before you squeeze.

There is no tank to fill in sepsis, and a vasodilated state is probably best managed with vasoconstrictors.  Giving a septic patient a fluid bolus will increase cardiac filling pressures, triggering release of naturetic peptides which cause vasodilation.  Thus in sepsis, fluids can be considered a vasodilator therapy.  If clinicians are concerned that there is inadequate preload, the LV end-diastolic volume should be measured with echo.

Pseudoaxiom two: fluids improve stroke volume

Patients with septic shock have a depressed Starling curve with a reduction in recruitable contractility via increased preload. > 50% of patients with septic shock have diastolic dysfunction which responds poorly to fluid therapy.

img_3269Ognibene FP, Parker MM, Natanson C, Shelhamer JH, Parrillo JE. Depressed left ventricular performance: response to volume infusion in patients with sepsis and septic shock. Chest 1988; 93: 903–1

 

Pseudoaxiom three: fluid stays in the circulating volume

In patients with septic shock less than 5% of administered fluid remains in the intravascular space at 1hr. This fluid leaks from the vascular compartment to enter the interstitium, causing organ dysfunction. The Marik-Philips EVLW curve illustrates the respiratory harms of fluid therapy in patients with increasing filling pressures. In the abdomen, increased initerstital oedema causes intra-abdominal hypertension, gut failure and renal failure.

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Pseudoaxiom four: albumin is the answer when crystalloid fails

The disrupted GCX enables translocation of albumin into the interstitium, where it  continues to exert an osmotic effect causing further interstitial oedema.

Lessons Learnt

The concept of fluid tolerance in pursuit of haemodynamic “stability” in shocked septic patients is as ill-fated as a hunt for a lost dog across a muddy paddock in the dark. Even though there was no surface water visible, the ground swallowed up my ute before I even realised I was on a path to trouble. So too do we drive our septic emergency department patients further into multi-organ dysfunction with iatrogenic salt-water drowning.

So how do I manage septic shock in the ED? After antibiotics are on board I perform a focused haemodynamic assessment using echo to examine preload (LVEDD or LVEDA), contractility (fractional shortening or fractional area change), filling pressures (interatrial septal motion), and diastolic function (E/A, E/e prime).  This takes less than 5 minutes. If patients have had no recent oral intake I replace guesstimated deficits (4, 2, 1 method) then commence maintenance fluids (D5W and providing Na, K, Mg as required [N.B. Australian RDI of sodium is 40mmol, not 154mmol]). I concurrently target a MAP of 65-70mmHg using a combination of noradrenaline, vasopressin and adrenaline, depending on the haemodynamic state.

So what happened to the ute you ask? Like the drowned patient needing CRRT and an inpatient bed before they break the NEAT 4-hour rule, I had to phone a critical care colleague who spent 4 hrs helping me dig the car out of the quagmire and haul it to dry ground.  Annie came back on her own volition without intervention and I scored a well earned “told you so” from her master.

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With thanks to Paul Marik, Thomas Woodcock, Rinaldo Bellomo and John Myburgh for inspiring me to care about fluids.

Special thanks to Caitlin Young for helping to dig me out of my stupidity.

The many faces of EM trainees: a quick feelgood post from a proud acting director

We’re looking forward to working with a great team in 2017 and the make up of it demonstrates the extraordinary diversity that makes up Emergency Medicine in Australia. Even the core group of people who have come straight to EM via intern and HMO years (and don’t get me wrong, that was me, falling in love with EM in term 1 of intern year and never toying with anything else) bring a great mix to the team. We have people from tiny rural Australian towns, and big cities, coming from the UK, Asia and Africa and via Canada, writing for the Victorian Institute of Forensic Medicine in their “spare time”, building a craft distillery, and lord knows what else I am yet to discover.

One of our advanced trainees next year is currently in the Pacific, doing a term in developing world EM while one of our new provisional trainees is in Liverpool England, doing a Diploma of Public Health; see her blog post here, describing her vision for a career combining EM and world health.

We’ve also got 4 new full-time consultants starting with us next year, all of them current or previous trainees. They include one of my first ever registrars, one of the first of our international graduate HMOs to be seduced into EM training, and two of our first advanced trainee recruits. I can’t tell you proud I am, of these four people, of the contribution our team was able to make to their development and of the distance that Bendigo ED has come, from a place where we didn’t even have a FACEM on every day and where there were frequently no ACEM trainees on the roster, to a place that has been able to train and retain 4 really high quality emergency physicians who would be a credit to any department anywhere in the world.

Thanks everyone for coming on board for 2017, a new hospital and more fantastic Emergency medicine training.