Sorry about this. I had planned to put up a post on the devolving role of the semi-rigid cervical spine collar two weeks ago. However, the more I read about it, the more I wrote and I ended up with a five page document. Waaay too long for a blog post!

So what I'm going to do instead is submit the original piece to a journal as an opinion piece and see if I can get it published. If that happens I'll put up a link to the article. In the meantime, as it may take some time to get through the editorial process, I don't want you all to have to wait, so this post will be a summarised version of the paper.

It came about, as many things do these days, from a tweet highlighting a post on the ScanCrit blogsite called "Cervical collar R.I.P." Ever since my days as an emergency medicine registrar there has been talk about the adverse effects of c-spine collars and the importance of early appropriate clearance to reduce the incidence of complications such as pressure wounds. I'd gotten used to ambulance crews arriving to the ED with all of their trauma patients in a collar "just as a precaution", feeling reassured that NEXUS and the Canadian c-spine rules would come to the patient's aid.

But as always, nothing stays the same and pre-hospital medicine had started to evolve. Back when Rollcage Medic was a newsletter that I typed out on my kitchen table, I wrote a piece on the lack of validity of applying these two ED-based studies to a pre-hospital population (ASMMR Newsletter, Vol 2, Issue 6, 2010). Since then, trials have looked at this, particularly for the Canadian rules and hybrid versions. And it has not stopped there.

More recently, there was a trial that looked at the mechanics of allowing conscious, pain-free volunteers to self-extricate from a vehicle with a c-spine collar in place versus a rescuer-facilitated extrication and found that there was less cervical spine motion with self-extrication (Cervical spine motion during extrication: a pilot study). That piqued my interest as it is notoriously time consuming trying to ease a competitor out of their crumpled race car using a full controlled extrication procedure. However, it was a very small pilot trial that amounted to proof-of-concept rather than practice-changer.

If you scan through pre-hospital and emergency services blogsites and recent articles, you'll find a constant theme questioning the protocolised over-use of the semi-rigid c-spine collar that appears to be more concerned with preventing litigation rather than injury. It seems there is a definite move to reduce the blanket application of c-spine collars to all trauma patients and to better target patients who might benefit from a collar. But even this is being questioned, as it turns out that there is not a whole lot of evidence showing a protective effect of c-spine collars and quite a bit showing adverse outcomes, albeit low quality evidence.

The main limitations of c-spine collar use are:
  • Aspiration risk - Most trauma patients are managed supine, usually on a spine (extrication) board. If the patient vomits, it can be difficult to quickly get them on their side.
  • Airway management - It is extremely challenging to intubate a patient who is wearing a semi-rigid collar and most, if not all, trauma centres and retrieval services will remove the collar, with appropriate caution, during the intubation procedure.
  • Intracranial pressure (ICP) elevation due to venous compression of the jugular veins
  • Pressure wounds
  • Fracture and spinal cord injury exacerbation - An incorrectly placed collar can defeat its purpose. However even a correctly placed collar can exacerbate a fracture line through distraction or exaggerated patient movement. While flexion and extension are certainly limited by a semi-rigid collar, lateral flexion and rotation are relatively more free movements
  • Complicates extrication (especially where helmet and frontal head restraint (FHR) removal are inhibited by limited cockpit space).
  • Creates a significant workload and time-drain in immobilisation, transportation and management for both pre-hospital and in-hospital staff.

And this brings me to the ScanCrit article. These guys have written a couple of posts questioning the exhaulted role of the semi-rigid cervical spine collar:

The last post, "Cervical collar R.I.P." discusses how a pre-hospital service in Bergen, Norway, has dispensed with the c-spine collar altogether, unless one of two situations is encountered:
  • Difficult extrication of unconscious patients where the EMS personnel can’t get in position to stabilise the patient’s head
  • Stabilising the neck during stretcher carrying in difficult terrain
If the patient is alert and co-operative, they are allowed to self-extricate without a collar, even if there is potential for injury; the argument being that the patient will consciously protect their own c-spine movement more effectively than rescuers or a collar. If the patient is unconscious, then the rescuers will extricate the patient, using an extrication board and manual stabilisation, but no collar unless one of the above two situations is encountered.

From the comments that follow the article, it would seem that they are not alone in this evolution of practice, despite it going against PHTLS, ATLS and EMST teaching. I'm not sure what Australian ambulance and retrieval services are doing; I couldn't find mention of it in the excellent Sydney HEMS or the Victorian state ambulance practice guidelines.

This has implications for motorsport rescue practice. On one hand, it would make our lives much easier if we could allow more competitors to self extricate where possible, even if there was a possibility of a cervical spinal (vertebral rather than cord) injury. Perhaps there is less of an issue where the competitor is unconscious, as the car is going to get cut apart, but there are still elements to consider such as access to the patient's airway and the potential for exacerbating a fracture line by a poorly applied collar.

Before we get too carried away though, there are some unique aspects of medicine and rescue at motorsport events. There is the balance of sheer speed and high deceleration forces countered by the protective components (crash structures, FHR/race harness/seat configuration). This makes extrapolation from civilian data tricky. There is the competitive agenda that may lead to a competitor understating their injury on first assessment, coupled with the rapidity of arrival of the medical team, especially at circuit events. And there is the greater publicity, particularly at high profile events, which puts pressure on us to be seen to be "doing the right thing".

Just as with our pre-hospital colleagues, we should not simply accept dogma; we should evolve our practice. This takes time and consideration and while there may be little evidence to support the protective role of the c-spine collar, we should make sure there is no evidence of harm in reducing its role as well. This will be an area, amongst many others, to keep watching.

As always, your comments and opinions are appreciated below.