1.24.2015

Do We Need C-Collars?


I was first on scene. An extended cab pickup with trailer was in the ditch on its side. Snow was falling, but the ditch was full of icy water. A woman was standing outside the truck "my husband is trapped inside." I had my partner call for extrication help. I opened the back door of the truck and a Rottweiler dog came flying out, barking, but eager to get out of the overturned rig.

 It was easy to see why. Water was pouring into the cab from a broken passenger window. 

"I can't get out." The driver -- from the passenger side of the front seat called when he saw me. "My arm's stuck."

 Broken plastic from the headliner had his arm trapped. He couldn't have been wearing a seat belt, so he was thrown across the front seat when the truck went over. His head and chest and left arm were out of the water -- which was strewn with debris and chunks of ice. The rest of him was hidden underwater. He might have had a leg entrapped as well.

The water was rising.

I slid into the truck. Standing on the transmission console, and holding on to the steering when, I crouched down, trying to keep myself out of the icy water. I pulled at the hard broken plastic until his arm came free.  The water was coming up, at least six inches in the past few minutes. With the help of another firefighter we pulled him out of the truck. As he emerged from the vehicle he said "my neck feels crunchy." 

"Grab a C-collar," I said from still inside the drowning truck. "And get him on a board." 

He ended up having a cervical spine fracture -- a couple of them in fact -- and yet this awkward, frantic extrication made his injury no worse. 
Portland Attorney George Cottrell's patent drawing for C-collar 1964
Is the use of Cervical Collars in trauma about to go away?

We are in the comment period on scientific evidence for the new American Heart Association guidelines which are set to change in 2015.

On the agenda is a recommendation against c-collar use. Other countries are already eliminating the c-collar from trauma guidelines except in the extrication of some unconscious patients.

Since the AHA drives so much of what we do in prehospital care, if this gets adopted it will mean a big change in practice.

It's a long time coming, but the evidence to support the c-collar just isn't there.

The C-Collar has been around for at least 30 years. In pre-hospital care, anyone involved in a major penetrating or blunt force trauma automatically gets a hard plastic splint around their neck.

The idea is that cervical spinal injuries are often asymptomatic until one little movement severs the spinal cord. Better to put on a c-collar ASAP as a precaution.

Now, however, the routine use of C-collars in trauma is being challenged.

That's because the science supporting the use of the c-collar is pretty weak. In fact there is no evidence it does any good in terms of preventing exacerbation of spinal cord injury. At the same time, it is not as benign as originally believed.

That said, changing away from cervical spine immobilization will likely be a hard thing for some in trauma community to accept. It has become ingrained in our algorithms. Spine boards and c-collars are what we do to trauma patients because, well, because it is what we do. Right?

Roll up on a car wreck and one EMT grabs c-spine while the other fits a collar. The patient doesn't come out of the car until he or she is awkwardly rotated and strapped to a hard board.

There has to be a good reason that we do all that, right?
"Whilst the immobilization of alert and co-operative patients may appear intuitive, and is strongly based on tradition, it is not supported by a reliable body of evidence," wrote Jonathan Benger, a professor of Emergency Care in Bristol, England. "We are unable to find any reports of acute deterioration in an alert and co-operative patient with cervical spine injury as a result of a failure to immobilize shortly after injury. 
As blogger Sanscrit noted in "The Curse of the C-Collar:"
The cervical collar has become a curse. It’s seen as the shining proof of good quality trauma care. No ambulance service dare deliver a patient to a trauma bay without a cervical collar. Not based on trauma mechanism or patient symptoms, but solely based on fear of criticism from the in-hospital ATLS-trained trauma team leader. Don’t get me wrong, ATSL has done a lot of good – but it can also be slow to adapt to new trends, and implement interventions in a dogmatic way instead of patient case based. Knowing ATLS is not an excuse to stop thinking.
Recent journal articles have pointed out that there are a lot of assumptions that have lead to the proliferation of c-collar use. A lot of science, however, is knocking those assumptions down one-by-one.

The first assumption is that trauma patients often have c-spine injuries that are not detectable. The evidence however doesn't bare this out. Studies have found that 0.7 percent of patient's considered high risk for head and neck trauma had significant c-spine injuries.

Everybody gets a collar -- yet less than one percent actually wind up having c-spine injuries.

Like any broken bone - if we think it is broken, we want to splint it. The c-collar is that splint, right? Yet we collar people even without evidence of c-spine injury as a precaution.

So what about those 0.7 percent of patients that end up having c-spine injuries? Does a c-collar applied in the field decrease complications? Does the c-collar do what it is intended to do?

So far the science says no.

Limited studies comparing immobilized vs non-immobilized patients have thus far found that there is no decrease in neurological damage from c-spine immobilization.

How can this be? 

In the awake patient, the patient will self-splint and gentle manipulation and transport won't make things worse. Tissue swelling also helps reduce movement in the patient who is not awake.

Drunks are somewhere between awake and not-awake. It is notoriously hard to get a collar on a drunk. Most of them rip them off once they are off the backboard and we don't invite physical altercations trying to keep them on. In my experience even the drunks that ended up having c-spine injuries didn't make things worse by not having a collar on.

Finally, if you have ever seen a collar on a drunk, you know it doesn't really restrict the movement of the neck all that much.

Yet, the pre-hospital c-collar is all about the precautionary principal. As Sanscrit wrote:
OK, OK, so spinal injuries aren’t that common, cervical collars don’t really immobilize the neck, and collars have never been proven to affect clinical outcome – but how about we just put the collar on anyway, to be on the safe side… It sure couldn’t do any harm?
This is an important point-- the underlying motivation for medical treatment is to first do no harm. Can a c-collar make things WORSE?

Studies have shown that c-collars increase pressure on jugular veins which increase Inter Cranial Pressure (ICP). Increasing ICP in a patient with a head injury is bad. C-collars also make the airway more difficult to manage and increases aspiration risk.

These are all bad things.

So how to we balance those risks with the potential prevention of worsening spine fracture?

Easy! There does not appear to be any benefit. So there is nothing to balance.

Cadaver studies have shown that having a c-collar in place actually makes neck injuries worse. Dead bodies were given a neck injury then placed in a c-collar. Imaging studies showed that the collar increased the fracture crease by more than 7 mm. 

The collar we put on millions of trauma patients every year has no proven benefit, no proven protection against secondary injuries. Still, we put it on with the A in ABC and take focus and time from more important interventions. For the patient with a high suspicion of spine injury, careful handling is needed – but not a cervical collar. For all other trauma patients, they will more than likely be better off without the collar. 
Further Reading


From Sanscrit's excellent blog:

The curse of the c-collar

Progress in Spinal Injury Managment

Comment on the new draft AHA/ILCOR SEERS HERE

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