JC: Self extrication vs. assisted extrication. St.Emlyn's • St Emlyn's

The last 2 years have seen the agreed wisdom of spinal immobilisation challenged. We have seen a paradigm shift in our attitude towards the use of cervical collar with some prehospital services now removing the automatic use of this device, and international organisations questioning their routine use. In brief we may be in a period of change and whilst there is not yet full consensus on whether the hard collar is dead as a device, it is an exciting time to watch and experience the debate.

It’s not just about collars though. Those of you familiar with anatomy will realise that the cervical spine is connected to the head superiorly and the body inferiorly. This is a really important fact as movement of either the head, or the body can move the cervical spine. I am of course being rather facetious here, but the point is that when we are considering the C-spine we cannot do it in isolation. In the real world it is generalised movements that may cause displacement of a potential neck injury.

It’s worth thinking again about when the c-spine may be injured. Firstly the initial trauma/impact causes the original injury and this is by far the most likely time to cause a significant spinal cord problem. Forces at the point of impact far outweigh those we might see when moving a patient in the ED. As hospital based emergency physicians we have a culture and practice of protecting the c-spine against tiny movements and in the most part we are pretty good at it, but we may forget about the difficult work our prehospital colleagues have in moving a patient from the scene to that nice stretcher that gets wheeled into the ED. Their job in extricating a patient from a vehicle for example is an intermediate period where theoretically the forces applied to the spine would be intermediate between those of initial impact and in-hospital management.

I’ve spent a fair bit of time in prehospital care and clearly spinal management of patients injured and entrapped in motor vehicles is a key part of that role. I’ve trained in all sorts of techniques with fire and rescue, and in well drilled teams it looks good. Just look at the myriad of courses on the internet on ways to get people out of a car involving lots of cutting tools and a fair bit of sweat. A lot of thought has gone into these techniques and although speed has improved over the years it is not uncommon for a controlled extrication to take quite a bit of time.

That’s fine as it’s good for the patient. Or is it?

Time for a pause I think as just because we do things now does not mean that we should do them forever. As an example, I can recall a patient who had a low speed RTC. They had minor damage to the vehicle, they knew this as they got out, had a look and phoned the emergency services. They had no initial pain but after 10-15 minutes their neck became a bit sore so they got back in their car to await the police. The police arrived, noted that the patient had neck pain and told them to stay in the vehicle until an ambulance was called. The ambulance arrived, immobilised the patient’s neck and then a controlled extrication was organised that involved cutting the roof off the car with the fire service and bringing the patient strapped to a spine board to the ED. This was clearly some time ago and INSANE, but it happens.

What if this was all crazy though? What if ‘controlled extrication’ causes more movement than self extrication, even for those patients with a cervical injury? Perhaps our own neuromuscular control is better than a team of fire and ambulance personnel pulling you up a spine board through your ‘newly modified’ convertible.

Last year I saw some data on this at the Trauma UK conference and I think it is that data that is published this month in the EMJ. Colleagues in Ireland have looked at patient movement comparing self extrication vs controlled/assisted extrication. The abstract is below, but you should always read the full paper which is open access this month.

What kind of paper is this?

This is an experimental paper. It’s not a clinical trial and that’s important. Experimental papers as proof of concept are fine, but they are very controlled settings with carefully crafted protocols. In general such studies are a lower level of evidence as compared to real world studies, but in this setting it is going to be very tricky to conduct something like a randomised trial to determine whether controlled vs assisted extrication makes a difference. At the moment this may be the best evidence we can muster.

What did they do?

Simply put, they used a biomechanical model to assess c-spine movements using 6 techniques to remove a patient from a car. At the most basic level the patient was asked to exit the vehicle with simple instructions alone (no collar). The team removing them were trained and capable and the patients were a range of body sizes and shapes. 16 mock patients were used in the study. Movement was assessed by a range of cameras designed to monitor cervical movements in each participant.

What did they find?

The smallest movements occured when the patient was extricated using a long board through the rear window of the car, although this was not statistically different from self extrication with/without a collar. They did find some increased movement when taking the patient out using rotation onto a spine board through the driver’s door or by lifting the patient out the drivers door with a Kendrick device in place.

What does this mean?

At first glance this is another blow for the traditional methods of spine control in prehospital care. The data supports the idea that if a patient can self extricate then they should. This seems to make a lot of sense and it would save a lot of time, resource and hassle. So perhaps that’s all great, but maybe not. Although the data here is believable there is one glaring problem with a study of this kind.

None of the ‘patients’ had a neck injury.

Anyone who has had neck or back pain will tell you that their movements change when they have pain. It is therefore likely that patients with back or neck pain would produce a different set of results to those here and I’m therefore finding it hard to extrapolate experimental data from normal volunteers through to a real world patients with potential injury. Similarly this study focused on the cervical spine movements, but as we said at the beginning the c-spine is connected to the body and the rest of the spine. We do not have data here about other movements that may affect spinal injury to the thoracic or lumbar areas.

In summary this paper is really interesting and I commend the authors on doing some great work that contributes to the debate. Is it definitive in telling us that self extrication is the best? No it’s not, but it does contribute to the debate on the subject. The question will be whether data like this can counter the juggernaut of training, traditional wisdom and financial interests embedded in current extrication techniques.

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