Another reason to be skeptical about collars

February 12, 2012 by  
Filed under All Updates, EMS, Resus, Trauma

More evidence that the obsession with cervical collars is founded on dogma rather than science


Background All trauma patients with a cervical spinal column injury or with a mechanism of injury with the potential to cause cervical spinal injury should be immobilised until a spinal injury is excluded. Immobilisation of the entire patient with a rigid cervical collar, backboard, head blocks with tape or straps is recommended by the Advanced Trauma Life Support guidelines. However there is insufficient evidence to support these guidelines.

Objective To analyse the effects on the range of motion of the addition of a rigid collar to head blocks strapped on a backboard.

Method The active range of motion of the cervical spine was determined by computerised digital dual inclinometry, in 10 healthy volunteers with a rigid collar, head blocks strapped on a padded spine board and a combination of both. Maximal opening of the mouth with all types of immobiliser in place was also measured.

Results The addition of a rigid collar to head blocks strapped on a spine board did not result in extra immobilisation of the cervical spine. Opening of the mouth was significantly reduced in patients with a rigid collar.

Conclusion Based on this proof of principle study and other previous evidence of adverse effects of rigid collars, the addition of a rigid collar to head blocks is considered unnecessary and potentially dangerous. Therefore the use of this combination of cervical spine immobilisers must be reconsidered.

Value of a rigid collar in addition to head blocks: a proof of principle study.
Emerg Med J. 2012 Feb;29(2):104-7

Comments

8 Responses to “Another reason to be skeptical about collars”

  1. Christopher on February 12th, 2012 23:06

    We’ve gone to towel rolls instead of head blocks, however, it’s not like it is any more or less backed up by evidence either…

    EMS cannot wait to ditch boarding and collaring.

  2. Mathew Mac Partlin on February 13th, 2012 01:40

    Yet another paper that challenges a common intervention that we mostly take for granted … Is anyone else concerned that if this dogma-challenging trend continues, we’ll be left with nothing and we’ll all be back to applying leeches and selling unctions.

    All facetiousness aside, I wonder how many ambulance personnel and retreivalists would be prepared to dispense with a collar on the basis of 10 healthy test subjects in a lab setting. Perhaps it allows people to feel even more confident to remove the collar if intubation prior to arrival in the resus bay is required.

    What does this mean for paediatric trauma? The APLS teaching has only recently removed the requirement to strap kids down in favour of applying a c-spine collar, albeit in the in-hospital rather than transport environment.

    Perhaps at least some of the message should be to use due care and consideration for the context of the patient you are managing, rather than ejecting an intervention out of hand for lack of evidence of benefit. Evidence of lack of benefit (slightly different) is probably more compelling, where the quality of the evidence is good, but it may also be worth considering the balance of lack of benefit-in-presence versus harm-in-absence. This goes for all evaluations of our various practices, not just hard collars. We are correct to question established practice, but extremism on either end is likely to be equally counter-productive.

    Was that too heavy? I haven’t had a hot chocolate for a few days …

  3. Seth on February 13th, 2012 10:45

    of course this isn’t a nail in the coffin for prehospital c-spine immobilization (or, if you prefer, immobiliSation), but it is one more study questioning the benefit.

    As these authors imply, there are a lot of problems with routine c-collaring — such as making intubation more difficult (is hypoxia bad in trauma?) and adding on-scene time.

    Anecdotally, I think we’ve all seen the calm & cooperative drunk transform into a thrashing agitated jerk with the application of a c-collar. And I would bet (reckon?) that his c-spine was better protected when he was sleeping

  4. Robert Simpson on February 13th, 2012 18:47

    I don’t think anyone is willing to ditch c-collars on the back of 10 healthy volunteers. However I am more than willing to ditch c-collars on the back of no evidence for efficacy in the first place, followed by an increasing body of evidence of harm and ineffectiveness subsequently.

    Certainly the evidence is sparse, but there are more and more studies coming out showing no reduction in movement of the c-spine when “immobilised”, and in some cases increased movement and distraction of the cervical vertebra. I’m sure Cliff has posted some of these studies previously. And however sparse the evidence of harm may be, it still vastly outweighs the evidence of benefit.

  5. Daniel Del Vecchio on February 14th, 2012 12:59

    I don’t think the purpose of those study are to change the practice butmore to bring a good argument that we a in desperate need of a larger big scale study on that issue. At my center it can take up to 24 hour before one can be clear from those colllar. How much ER time and hospitalisation wecould save. That is a lot of money. Especially in a center where we get a lot of ski injury that their protocol is to “board” everyone

  6. Tim Leeuwenburg on February 15th, 2012 17:29

    Hang on, I thought we’d ditched head blocks for the conscious? All those probs of potentially torqueing the restrained head against combatative body…

    Anyhow, isn’t a C collar just a marker to put on people to indicate they’ve been involved in trauma?

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