Traumatic Cardiac Arrest – A paradigm shift: Part 2

You arrive on scene to find a car that has had a frontal impact with a gum tree. The engine bay is wrapped around the tree trunk, horn blaring. The patient is slumped over the steering wheel, with a weak carotid pulse that dissipates immediately. Are you confident with your next step? What are the priorities here? Do we declare them or work on them? Well, luckily, you’ve read Traumatic Cardiac Arrest Part 1, so you know that this is game on.

We know that there are four primary pathologies that we can potentially treat. But how do we do this?

Hypoxia is the end result of a broad range of underlying insults. However, it doesn’t matter whether the cause is airway obstruction, brain impact apnoea, or a lung pathology, the fix all starts the same – basics. The term basic, however, is a misnomer. The ability to use a bag-valve mask effectively is a skill that will serve you well in your career, whether it be a failed airway algorithm or trying to judge your priorities in a traumatic cardiac arrest. Practise this skill ‘til no end. Whilst these patients do benefit from a definitive airway, the initial goal is all about air in and out.

The management of tension pneumothorax and cardiac tamponade conceptually is easy…decompress them. However, pre-hospital medicine is far from simple. Anyone can be taught how to place a needle into a set location. But what happens when it does not work? Mastering your practice is more than learning the fundamental skill. It is about understanding when to do it. It is about picking up on the cues that suggest that it will be ineffective. It is about knowing what the patient needs, and the options that are available to get the patient what they need – even if it is not in your tool kit. So how do we deal with these pathologies? We know our equipment, we know our procedures, we know our fail safes, and most importantly, we know our limitations.

Bleeding is undoubtedly the elephant in the room. It causes the greatest number of traumatic deaths that were potentially reversible. Therefore, we need to be experts at dealing with it. Many ambulance services now have a repertoire of options to treat external haemorrhages. Ranging from basic and modified pad and bandages, to haemostatic dressings and tourniquets. Junctional haemorrhage is an important subgroup of these patients that we are learning a lot from the military. They present a unique challenge due to the pairing of vulnerable major vessels with inconvenient locations. However, let us not forget about internal haemorrhages. Potentially amenable locations include long bones and pelvic regions. However, looking to the future, and in some cases the present, we have more dramatic methods of controlling other forms of internal haemorrhage such as REBOA and thoracotomy.

There is ongoing controversy about the role of cardiac compressions and adrenaline in the traumatic arrest patient. On one hand, it makes no physiological sense to perform compressions, and doing so may interrupt more important interventions. The counter to this is that not all traumatic deaths are equal, and it’s hard to generalise the priority of an intervention, with such vast aetiologies. Arguably, the greatest concern is if this apparent traumatic arrest, actually had a medical origin. Isn’t that one to think about. That patient that wrapped his car around the tree… could he have had crushing chest pain and a VF arrest prior to the car leaving the road?

Traumatic Cardiac Arrest – A paradigm shift: Part 1

Evolution is a natural, and essential, part of medicine. During the 18th century, blowing tobacco smoke into the anus was believed to be an effective treatment for drownings. Whilst this is a time in history where we can look back and question logic – bloodletting was common too – we need not jump onto our high horses about previous practices, but rather stimulate introspection about how we currently practice medicine. Are we ourselves practising medicine in manner that will be considered comical in 100 years’ time?

Historically, traumatic cardiac arrest was mostly thought to be a futile condition. Once a traumatic pathology had progressed to the point of cardiac arrest, it was a common belief that the patient could not survive. However, thanks to the modern era of evidence-based medicine, we have re-shaped our perceptions about these patients – there are survivors. The question remained though, who are they, and how do we save them? 

The most compelling arguments originally came from post-mortem studies where the cause of death was derived. The results were profound. What we saw, was that there were a significant cohort of patients who could have been saved. These were the patients who had died from:

  1. Hypoxia
  2. Hypovolemia
  3. Tension pneumothorax
  4. Cardiac Tamponade

In modern trauma systems, we are seeing survival rates anywhere from 5% up to 27%. These are big numbers, particularly when we take into account that the vast majority of the trauma patients are younger, fitter and healthier individuals compared with their medical cardiac arrest counterparts.

That being said, we do need to recognise that a large cohort of patients will have catastrophic injuries and will inevitably die. The challenge that has faced clinicians and researchers over the years, is how do we predict patients with such injuries.

What we have learnt is that there are very few predictors of futility in traumatic cardiac arrest. Signs previously thought to be synonymous with death, such as asystole and fixed dilated pupils, have since been debunked. Current recommendations for withholding resuscitation are centred around:

  1. No signs of life within the preceding 15 minutes;
  2. Massive trauma incompatible with survival, such as decapitation and loss of brain tissue.

There are some pretty impressive injuries that fall outside of these categories that previously would not have been worked on. It makes you think, doesn’t it?

So what is the paradigm shift? It’s a mentality.

Let’s not throw the baby out with the bathwater. Let’s resuscitate these patients. We’ll throw everything at them and try and capture the ones that can be saved, and accept those that cannot be. Be an advocate for your patient.

To hear more about this, listen to Episode 14: Traumatic Arrest – A Paradigm Shift.