Brought in by Ambulance, #3: My leg hurts! Well, here's your C-collar...

Case Scenario:
You are doing your second supervisor ride along and hoping that your white cloud of peace will disperse so you can see some St. Louis action. You are called emergently to MVC vs. two pedestrians. On arrival to the scene, you find one patient on the ground with an open fracture of his leg.  ABC’s are fine. The patient notes the car came around the corner and hit his leg. He remembers everything, and complains only of his leg hurting. A quick examination of his neck reveals no midline tenderness and no pain with range of motion. However, secondary to his distracting injury a C-collar was placed. As the ambulance drives away with the patient, you wonder what the evidence behind C-collar use is, and if it was really necessary to place a collar in this gentleman without any neck pain.

Current EBM evidence:
Most of the recommendations on c-collar use are based on opinion and tradition. The American Association of Neurological Surgeons and the Congress of Neurological Surgeons Joint Commission have made recommendations; however, most of these recommendations are based on Level III evidence. Unfortunately, there is a paucity of evidence for the implementation and continued use of C-spine collars. In fact, a Cochrane review in 2007 noted there wasn’t a single prospective RCT on c-collar use.

Currently, most of the validated evidence we have for spinal cord protection is in terms of imaging. Both the NEXUS criteria and the Canadian C-spine rules have been validated, and are used by the American Association of Neurological Surgeons and the Congress of Neurological Surgeons Joint Commission on their official recommendations on the management of acute spinal cord injury. The NEXUS criteria and the Canadian C-spine rules have been applied in the pre-hospital setting; those who will require imaging should therefore be placed in a cervical collar for C-spine stabilization.

Nexus Criteria:
No imaging if all of the following are true:
●No posterior midline cervical tenderness
●Normal level of alertness
●No evidence of intoxication
●No abnormal neurologic findings
●No painful distracting injuries

There has never been any control trial on patients examining if C-collars actually stabilize the spine. There have been a multitude of trials on volunteers and models, many of which have contradicting results. While some studies show that C-collars do stabilize the neck, others show that collars may actually increase neck movement. In a controversial study done by Hauswald et.al, un-immobilized patients in Malaysia had better neurological outcome than similar patients who were immobilized in New Mexico. While this study compared no immobilization to full spinal immobilization (and therefore flawed in the analysis), the overall philosophy that second injury due to transport is rare as the forces are weak compared to the force required to injure the spinal cord may still hold true.

While the evidence to support the use of C-collars is weak, there is an increasing amount of evidence noting potential risks and morbidity associated with C-collar use. While the goal of C- collars is to reduce movement of the cervical spine and protect the spinal cord, a few case studies have shown that forcing a neck into “anatomical position” can actually cause spinal cord injury, particularly in patients with ankylosing spondylitis. A study on cadavers noted that extrication collars caused an increased degree of separation between vertebrae when there is a dissociative injury.

In a systematic review done by Sparke et. al, there have been a few studies noting an increase of ICP pressure with the placement of C-collar. It is estimated that risk of increased ICP is 35.8%. It is thought that the increased ICP is secondary to pressure placed on the jugular veins (causing venous congestion); however there is no real knowledge of the etiology of the increased ICP. Sparke et. al also did a review of the risk of tissue ulcerations secondary to C-collar placement. A review of 14 studies showed the incidence of hospital acquired pressure ulcers from a C-collar range from 23.9-44%. While the review noted that the measurement of pressure from the C-collars was highly variable between studies, pressures from C-collars can be quite elevated (up to 150mmgHg). The review also notes that none of the studies examined in the review were randomized control trials.

The immobilization of the neck can cause increased difficulty in airway management and protection. It is often much more difficult to intubate a patient that has been placed in a C-collar. Patients who do not require intubation are at an increased risk of aspiration with vomiting.

Additionally, once a C-collar has been placed, the patient may be more likely to undergo imaging to have his C-spine cleared. In a study done by Kim et. al., children who were placed in a C-collar were much more likely to undergo imaging to clear the c-spine (56.6 vs 13.4%) and were much more likely to be admitted to the hospital 41.6 vs 14.3%). This can have serious implications on the length of stay on the patient, as well as overall cost to the patient and the hospital.

While the evidence supporting C-collars is minimal, the potential consequence of movement causing additional spinal cord injury is so severe that much better evidence will be required before a change can occur. However, there is the potential to try and reduce the number of C-collars placed, especially on low-risk individuals. In a prospective study done by Rose et. al, it was found that physical exam (no neuro deficit and no midline tenderness or pain with range of motion) was over 99% sensitive with a 99% negative predictive value. In this study, all patients with GCS greater than or equal to 14 were attempted to be clinically cleared regardless of ethanol level or presence of distracting injuries. All patients received CT imaging of their spine, even if they were clinically cleared. Of the 464 patients with distracting injuries that were clinically cleared, only one was found to have C-spine fracture (C2 lateral mass). It should be noted that of the 544 patients without distracting injury that were cleared clinically, one was also found to have a C-spine injury (C6 lamina and C7 superior facet).

Take Home:
-No prospective randomized study on use of c-collars
-There are possible adverse outcomes with use of c-collars (eg increased ICP, pressure ulcers)
-There is evidence supporting clearing c-collar clinically, even with distracting injuries

References:
1. Walters BC, Hadley MN, Hurlbert RJ, Aarabi B, Dhall SS, Gelb DE, Harrigan MR, Rozelle CJ, Ryken TC, Theodore N; American Association of Neurological Surgeons; Congress of Neurological Surgeons. Guidelines for the management of acute cervical spine and spinal cord injuries: 2013 update. Neurosurgery. 2013 Aug;60 Suppl 1:82-91.
2. Sundstrøm T, Asbjørnsen H, Habiba S, Sunde GA, Wester K.. Prehospital Use of Cervical Collars in Trauma Patients: A Critical Review. J Neurotrauma. 2014 Mar 15;31(6):531-40.
3. Hauswald M, Ong G, Tandberg D, Omar Z. Out-of-hospital spinal immobilization: its effect on neurologic injury. Acad Emerg Med. 1998 Mar;5(3):214-9.
4. Ben-Galim P, Dreiangel N, Mattox KL, Reitman CA, Kalantar SB, Hipp JA. Extrication collars can result in abnormal separation between vertebrae in the presence of a dissociative injury. J Trauma. 2010 Aug;69(2):447-50.
5. Papadopoulos MC, Chakraborty A, Waldron G, Bell BA. Lesson of the week: exacerbating cervical spine injury by applying a hard collar. BMJ. 1999 Jul 17;319(7203):171-2.
6. Sparke A, Voss S, Benger J. The measurement of tissue interface pressures and changes in jugular venous parameters associated with cervical immobilisation devices: a systematic review. Scand J Trauma Resusc Emerg Med. 2013 Dec 3;21:81.
7. Leonard J, Mao J, Jaffe DM. Potential adverse effects of spinal immobilization in children. Prehosp. Emerg. Care 16, 513-518.
8. Rose MK, Rosal LM, Gonzalez RP, Rostas JW, Baker JA, Simmons JD, Frotan MA, Brevard SB. Clinical clearance of the cervical spine in patients with distracting injuries: It is time to dispel the myth. J Trauma Acute Care Surg. 2012 Aug;73(2):498-502.

Submitted by Melissa Kroll, PGY-2.
Faculty Reviewed by Phil Moy.

Brought In By Ambulance, #1: Vagal maneuvers in SVT

In this section, we will highlight EBM queries targeted to the prehospital care of patients.


Without further ado...
You respond to a call-out for "palpitations." You arrive on-scene to find a middle-age female patient who is awake, well-oriented, and talking to you in complete sentences. She is complaining of her heart "fluttering," and reports feeling somewhat short of breath and anxious. She reports a prior history of palpitations without a clear working diagnosis. Cardiac leads are placed, and the monitor shows a well-organized narrow-complex rhythm with rate in the 160s. Her BP is stable. Her skin appears warm and well-perfused. As the EMT's are working on establishing IV access, you wonder how effective vagal maneuvers are in terminating SVT.

Clinical Question:

Which vagal maneuver, if any, should be used to terminate SVT?

Literature:

In two studies, the authors found that the valsalva maneuver was more successful in terminating SVT than carotid massage or ice-to-face. In one case series, valsalva was able to terminate SVT in 54% of patients. These study authors also found that a right carotid massage was slightly more efficacious than a left carotid massage in terminating SVT (17% vs 5%). Attempting to provoke the diving reflex with ice had the same efficacy as the right carotid massage (17%)¹.

A second study of prehospital treatment of SVT found that valsalva was more efficacious if the patient was supine, the maneuver was sustained for 15 seconds, and a pressure of 40mm Hg was obtained. The study again found that valsalva was more successful than carotid sinus massage and the ice-to-the face technique².

In a third study, there was a trend toward valsalva being more effective than carotid sinus massage.  Valsalva had a success rate of 19.4% vs 10.5% for carotid sinus massage, though these figures did not reach statistical significance. When initial carotid massage did not resolve the SVT, valsalva was able to convert in 16.9% cases, versus 14% when carotid massage was used after failed valsalva.  Overall, the conversion rate was 27.7%³.

Valsalva maneuver is inherently safer than a carotid massage, as there is no risk of causing decreased carotid perfusion or dislodging clot. The most difficult part is ensuring full patient participation, especially in pediatric patients. One method that has been suggested to promote valsalva in pediatric patients is asking the child to blow through a straw. Several reports also suggest that valsalva maneuver is more efficacious than carotid massage in terminating SVT. There is also limited data to suggest that a right carotid massage is better than a left carotid massage. Given that Valsalva is safer and may be more efficacious, attempts at terminating SVT should begin with Valsalva.

Take home points:

- In available reports, valsalva maneuver appears to be the most efficacious of vagal maneuvers in terminating SVT. It may be effective anywhere from 20-50% of the time.

References:

1. Mehta D, Wafa S, Ward DE, Camm AJ. Relative efficacy of various physical manoeuvres in the termination of junctional tachycardia. Lancet. 1988;1(8596):1181.

2. Smith G, Morgans A, Boyel M. Use of the Valsalva manoeuvre in the prehospital setting: a review of the literature. Emerg Med J. 2009 Jan;26(1):8-10

3. Lim SH, Anantharaman V, Teo WS, Goh PP, Tan AT. Comparison of treatment of supraventricular tachycardia by Valsalva maneuver and carotid sinus massage. Ann Emerg Med. 1998 Jan;31(1):30-35

Contributed by Steven Hung, PGY-2

Anaphylaxis: I can't breathe!

On an EMS ride along, you respond to a dispatch for a patient having an allergic reaction to some food.  You arrive on scene and find the patient having difficulty speaking and having stridor, in clear respiratory distress.

Clinical Question:

What is the ideal treatment of anaphylaxis?

Literature:

The lifetime prevalence of anaphylaxis is estimated between 0.5-2% with mortality rates ranging between 0.65%-2%, resulting in approximately 1500 deaths annually.  When fatal, death usually occurs minutes after contact with the trigger.  Fatal food reactions usually caused respiratory arrest 30-35 minutes after initial contact.

The first line treatment is epinephrine since it counters many of the symptoms of anaphylaxis.  As an alpha-receptor agonist, it reverses peripheral vasodilation and reduces edema.  The beta-receptor activity dilates bronchial airways, increases myocardial contraction, suppresses histamine and leukotriene release, inhibits mast cell activation.

There are several methods for epinephrine injection.  In a study comparing IM vs subcutaneously route, it found that an IM injection of epinephrine in the anterolateral aspect of the thigh achieved a higher and faster plasma epinephrine concentration peak.  IM injection into the deltoid of the arm as well as subcutaneous injection into the deltoid had lower and longer time to peak concentrations.  The greater blood supply to the vastus lateralis muscle is theorized to account for this difference.  The IM injection site also offers a greater margin of safety as well as ease of administration compared to IV epinephrine.  The IM dose of epinephrine can be repeated in 5-15 minutes if symptoms are not improving.  IV epinephrine has been associated with fatal cardiac arrhythmias and myocardial infarction and should be reserved for those unresponsive to conventional treatment in a controlled setting.

The recommended dose of epinephrine IM is 0.3-0.5mg of 1:1000 epinephrine (0.3-0.5 ml).  For pediatric patients, the recommended dosage is 0.01mg/kg.  Initial resuscitation should also include a bolus of normal saline given the vasodilatory effects of anaphylaxis.

Antihistamines are considered second line treatment.  H1 blockers such as diphenhydramine can be given to alleviate cutaneous symptoms, however it does not acutely treat the life threatening aspects of anaphylaxis.  There is little evidence to support the routine use of H2 blockers.  Steroids can also be given, although there is also weak evidence for their use.  In theory, steroids are used to prevent a biphasic reaction (when symptoms resolve, but recur within 1-72h) but there is little evidence that it is effective in reducing biphasic reactions.  Many providers will give a one time dose of methylprednisolone 1-2mg/kg in the ED, which is generally considered sufficient.  Bronchodilators can also be given if the patient is wheezing, experiencing dyspnea, or coughing.

Take home points:

-First line treatment for anaphylaxis is epinephrine 0.3-0.5mg IM in anterolateral thigh
-IV fluids should be given to counteract vasodilation
-H1 blocker may provide symptomatic relief, however is not first line therapy
-Bronchodilators may provide symptomatic relief
-H2 blockers have not been proven to be effective
-Steroids have not been proven to be effective

References:

1)Pumphrey RS. Lessons for management of anaphylaxis from a study of fatal reactions. Clin Exp Allergy. 2000;30(8):1144-1150
2) Soar J, Pumphrey R, Cant A, Clarke S, Corbett A, Dawson P, Ewan P, Foex B, Gabbott D, Griffiths M, Hall J, Harper N, Jewkes F, Maconochie I, Mitchell S, Nasser S, Nolan J, Rylance G, Sheikh A, Unsworth DJ, Warrell D. Emergency treatment of anaphylactic reactions – guidelines for healthcare providers. Resuscitation. 2008 May;77(2):157-69
3) Simons FE, Ardusso LR, Bilò MB, Cardona V, Ebisawa M, El-Gamal YM, Lieberman P, Lockey RF, Muraro A, Roberts G, Sanchez-Borges M, Sheikh A, Shek LP, Wallace DV, Worm M. International consensus on (ICON) anaphylaxis. World Allergy Organ J. 2014 May;7(1):9
4) Simons FE, Gu X, Simons KJ. Epinephrine absorption in adults: intramuscular versus subcutaneous injection. J Allergy Clin Immunol. 2001 Nov;108(5):871-3.
5) Zilberstein J, McCurdy MT, Winters ME. Anaphylaxis. J Emerg Med. 2014 Aug;47(20):182-7

Contributed by Steven Hung, PGY-2

#FOAMed Digest No. 3: You Need Me On That Wall

Emergency Medicine physicians practice in a unique environment. We must synthesize plans for  diagnosis, management, and disposition while utilizing input from almost every subspecialty, and the ED is the ultimate proving ground for diagnostic tests and treatment modalities of every sort. Unsurprisingly, a fair deal of controversy and debate exists regarding the optimum management of patients. (For reference, see any Trauma Case Conference featuring Drs. Schuerer and Aubin.) The “best evidence” is often poor evidence. We in Emergency Medicine retain the rebellious spirit of our founders, and are always looking for new and innovative techniques. Some physicians are too quick to jump on the bandwagon, and others lag behind the curve when it comes to adopting new practices.

The selections this time around are not meant to tell you the best way to do things. The algorithms and practice patterns suggested are not universally adopted, written in textbooks, or taught as part of any standard curriculum. They are meant to promote thought, to prompt you to read the primary literature for yourself, to encourage you to seek the opinions of other experts on the subject, and to form your own conclusions. Hopefully they will inspire you to suggest new ideas to your seniors and attendings during your next shift – or even question ideas you think are unsound. Maybe, just maybe, they will even inspire a new research or QI project. FOAMed is by design perfectly adapted to assist you in this quest.

Ramblers, let’s get ramblin’.

Three Stars:

1. Ken Milne at the Skeptic’s Guide to Emergency Medicine pretty much sets the bar when it comes to FOAMed of the latest EBM topics. He asks his clinical questions in the PICO format, he applies a rigorous quality checklist when analyzing the available literature, and includes in his discussion other FOAMed experts (including on occasion our very own Chris R. Carpenter, a.k.a. “Captain Cranium”). This episode he turns his skeptical eye to a topic sure to generate heated discussions for years to come: tPA for stroke.

2. If there’s anyone that looms larger in the ED Critical Care world than Weingart, it’s Resuscitationist Extraordinaire Cliff Reid. His lecture from the SMACC Gold conference hit resuscitation dogma like an A-bomb, leaving irradiated bits of unfounded practice patterns strewn about the Outback countryside.

(EXTRA CREDIT: Reid’s talk from the original SMACC conference, “Making Things Happen,” should be required viewing for anyone wanting to be a Trauma Senior someday.)

3. If pediatric surgeons have come to accept ultrasound as a stand-alone diagnostic method for appendicitis, maybe there’s hope that someday ultrasound can also be used as a radiation-sparing technique for diagnosis of small bowel obstruction. Academic Life in EM has an excellent run-down of the technique and comparative research studies.
(EXTRA CREDIT: The book Evidence-Based Emergency Care, authored in part by our own Captain Cranium Chris R. Carpenter, has a chapter dedicated to the inferiority of plain films for SBO diagnosis. You can read it for free online via Becker Library.)

Oldie But Goodie:

I think here in a few more years this will reach “accepted standard practice” level, and maybe even “textbook” level, but it’s not there yet. It should be: there’s good evidence to show kayexelate doesn’t work, and may even cause harm. Let Weingart and the PaperChase fellows from EM:RAP give you the ammunition you need to stand up to any pesky floor seniors.

F(FN)OAMed:

In a very enlightening segment from this month’s EM:RAP, Rob Orman interviews a community ED practitioner, Dr. Cameron Berg, regarding his hospital’s new Accelerated Diagnostic Protocol for low-risk chest pain. While his exact algorithm hasn’t been externally validated and probably isn’t ready for prime-time at our shop, the evidence-based and pragmatic approach is certainly worth considering. And he provides links to almost all of his references in the show notes!

The Gunner Files:

1. The “Research & Reviews” segment on Life in the Fast Lane is worth checking out every week. A group of some of the brightest minds in the FOAMed world get together and spoon-feed us summaries some of the most relevant, practice-changing, or downright strangest papers in the EM literature.

2. Josh Farkas over at PulmCrit wrote an excellent piece laying out his argument for super-high-flow NC (think 30-45L!) as an acceptable method of preoxygenation before RSI. It’s also got a good rundown of apneic oxygenation using NC (which we all should be doing every time), and an enlightening counterpoint from the grand maester of ED Critical Care, Scott Weingart.

3. Pediatric EM expert Sean Fox provides an excellent summary of the neonatal ALTE on his blog Pediatric EM Morsels.

4. Two EM airway heavyweights, Rich Levitan and Reuben Strayer, slug it out in the ultimate Direct Laryngoscopy vs Video Laryngoscopy debate, posted to the Prehospital and Retrieval Medicine podcast hosted by Minh Le Cong.

5. All of us will be the bearer of the -07 phone at some point, and that means you better have your act together when discussing decision-making capacity. Bill Johnston, EMT-P and author of the excellent blog Prehospital Wisdom, shares his fundamentally sound and no-bullshit method for determining capacity in the field.

In the words of Ken Milne: “Meet ‘em, greet ‘em, treat ‘em, and street ‘em!”

Sam Smith, PGY-3

#FOAMed Digest No. 2: Breathless Love

Welcome back! Fresh new FOAMy goodness for you, this time with an emphasis on airway and pulmonary care. Let’s do it!

Three Stars:

1. No way around it: “Delayed Sequence Intubation” is the new hotness. If you want to be one of the cool kids, you better get on board. I’ll let the more graphically-minded folks at EMCurious lay it all out for you with a prototypical case. Don’t miss the links – more excellent FOAMed resources on DSI.

(And Weingart’s seminal paper on the subject is required reading at this point.)

(And, oh yeah, ketamine does NOT increase ICP. Let’s use these two systematic reviews 1 & 2 to stop the foolishness already.)

2. Someday you will need to perform a cricothyrotomy. Accept it as reality, and do everything you can to prepare for it. Start here, with Weingart’s lecture on the surgical airway delivered at the SMACC Gold conference last fall. This page from the EMCrit blog has compiled all sorts of great surgical airway resources from around the FOAMed world all in one spot, including can’t-miss stuff about the scalpel-finger-bougie technique and Weingart’s pre-intubation checklist. You should probably add it to your favorites list now.

3. Wouldn’t be a FOAMed Digest without getting a little off-topic, and Rick Body’s recent contributions over at St. Elmyn’s regarding ACS & “low-risk” chest pain in the ED are too good to pass up. Great post analyzing his recent paper, which concluded ED physicians simply aren’t capable of ruling out ACS in chest pain patients with an acceptable accuracy using only the clinical exam. Dr. Body also gives you a run-down of how to properly utilize high-sensitivity troponin in his talk from SMACC Gold.

(Link to Body's paper here.)

Oldie But Goodie:

By the end of our Ultrasound rotation, we can all diagnose pneumothorax with ultrasound at the bedside. It’s time to take it next-level. A-lines, B-lines, pneumonia vs edema…the experts at the Ultrasound Podcast help you figure it all out in a two-part 1 & 2 podcast.

F(FN)OAMed:

Sanjay Arora and Mike Menchine, hosts of the PaperChase segment on EM:RAP, summarize the current literature about how terrible we are at adequately sedating patients after RSI. Roc lasts longer than Sux – the patients won’t be able to tell us they need sedation!

(Links to relevant papers in the show notes.)

The Gunner Files:

1. Brett Sweeny at EMDocs provides an exhaustive review of FOAMed resources regarding permissive hypotension in trauma. Great lectures and podcasts from some of the brightest minds in EM & trauma surgery.

2. We’re seeing it already – asthma cases are starting to pile up over on the SLCH side. Luckiliy for you, Pediatric EM rockstar Andy Sloas just published an excellent podcast on the evaluation and management of asthma in the Peds ED.

3. Next time you’re consulting Ortho or Plastics for a hand injury, sound like you know what you’re talking about. The folks over at EMin5 hit you with the quick rundown on the neuro exam of the hand.

4. Last week, St. Elmyn’s helped the rooks get up to speed when it came to dealing with the dyspneic patient in the ED (and I bet the seniors learned a thing or two as well). This time, get your mind right when faced with a syncopal patient.

5. Who doesn’t love infographics? And if they actually help us learn something about managing septic patients, that’s just a bonus! Very well done by EMCurious, with embedded links to the relevant studies!

6. New podcast from R.E.B.E.L.EM, summarizing the results of a meta-analysis just published this month in Annals which concluded prehospital application of NIPPV in patients with severe respiratory distress regardless of cause reduced need for intubation (NNT 8) and in-hospital mortality (NNT 18). 

w00t prehospital medicine!
(Original pub here.)

That’s all, folks! Go get your learn on!

Sam Smith, PGY-3

Rigid Backboard for Spinal Immobilization?

You are working a busy overnight shift when you see EMS bring in a “trauma packaged” patient – a young, healthy-appearing female, on a hard backboard and with a C-collar in place. Per their report, she was the restrained driver of a vehicle struck from behind at a low rate of speed while stopped at a red light. The patient denies LOC, but is endorsing pain in her neck and all the way down her back. She is complaining that the backboard is uncomfortable and making her back pain worse.

Clinical Question: 

What are the indications for prehospital rigid spine immobilization? Could it have been deferred in this patient?

Literature:

Despite the dogmatic and traditional use of rigid backboards for extrication and transport of patients with possible blunt traumatic injury of the spine, it is not an altogether benign intervention. The discomfort associated with bumpy ambulance rides while secured to a rigid board may worsen a patient’s initial presentation to the ED providers such that unnecessary spinal imaging is ordered. Prolonged transport times on rigid boards have been associated with pressure sore formation and respiratory compromise.

The use of rigid spine immobilization by prehospital providers has become based largely on mechanism of injury and concern for possible spinal cord compromise, rather than being based on signs or symptoms of spinal injury itself. This is the opposite of how diagnosis of such injuries is handled once the patient arrives to the ED. As the validation studies of the NEXUS and Canadian C-spine rules have shown, the risk of a C-spine fracture in a patient with normal mental status and without clinical signs or symptoms of spinal cord injury or distracting injury is vanishingly small.

With this in mind, the National Association of EMS Physicians (NAEMSP) and the American College of Surgeons Committee on Trauma published a position paper in the journal Prehospital Emergency Care entitled “Indications for Prehospital Spinal Immobilization.” This paper (and the accompanying resource document) outlines who should and should not be immobilized based on best evidence.

To begin, patients must first be assessed for a mechanism of injury capable of causing spinal cord injury. This is somewhat open to interpretation by EMS providers, and can vary for different patient populations (i.e., a fall from standing would be a very low-risk mechanism for healthy young adult male but much higher risk in an elderly, frail female). The document specifically addresses penetrating wounds, based on evidence published in a paper in the Journal of Trauma in 2010. Basically, if a penetrating wound to the head, neck, or torso does not obviously affect the area of the spine and is not associated with evidence of spinal injury (including focal neurologic deficits), there is no need for rigid immobilization.

If the mechanism is determined to be a risk for spinal cord injury, the EMS provider must then perform a spinal assessment, which is largely derived from the NEXUS and Canadian rules for C-spine imaging. The spinal assessment is “positive” if there is any midline tenderness, palpable/visible midline deformity, or a new neurologic deficit. Immobilization must also be considered for those in which a spinal assessment is unreliable. This includes patients with altered mental status, who are intoxicated with alcohol or drugs, who have a painful distracting injury (by NAESMP criteria, a long bone fracture proximal to the wrists or ankles), or who are otherwise unable to fully participate in the exam due to a language barrier or due to age (i.e., pre-verbal pediatric patients).

If this assessment is negative, NAESMP recommends a C-collar should still be placed if the patient is over 65 (due to increased risk of C-spine injury in this population), but the patient does not require further spinal immobilization and can be transported in position of comfort. Obviously, a C-collar should be placed on any patient if there is midline tenderness in the C-spine.

Interestingly, a study from the Journal of Emergency Medicine published in 2013 reported data from a high-speed infrared motion analysis of healthy volunteers that showed those who extricated themselves with a C-collar in place had less spinal motion than those who were told to hold still while EMS crews attempted extrication themselves. Thus, if the patient is able to extricate themselves and able to ambulate, they should be allowed to do so. If their spinal assessment is positive, they can then be secured to the stretcher with seatbelts, which has been shown to be as effective at immobilizing the T- and L-spine as a rigid backboard. If the patient cannot self-extricate, they can be extricated using standard equipment and transported to the stretcher via a hard backboard. However, he or she should be logrolled off the backboard once reaching the stretcher to minimize time spent on the hard board. The safety of this approach is reinforced by data from other studies which have shown an extremely remote risk of significant (i.e., surgical) T- or L-spine injury in restrained persons in low-risk MVCs.

Take home: 

Remember that securing to the stretcher is an effective mode of spinal immobilization. Rigid backboards should probably be reserved for transfer of a nonambulatory patient from the scene to the stretcher, and should be removed as soon as possible.

References:

1) Prehosp Emerg Care. 2014;18(2):306-14.
2) J Trauma. 2010;68(1):115-20.
3) J Emerg Med. 2013;44(1):122-7.
4) Spine J. 2014. PMID 24486471 [EPub].
5) J Emerg Med. 2006;31(4):403-5.
6) Injury. 2006;36(4):519-25.

Kindly contributed by Sam Smith, PGY-3.