Prehospital Spinal Clearance Part II

A closer look at the research...

With the start of this topic, I thought I would get by with some easy research and criticisms. As I dove into this subject I soon realized it wasn't going to be that easy. In part one, I explained what struck the question and I began to look further into statements made by Trauma.org. The replies to my first post have given me new ideas and directions. The research is all there for me, and there isn't a need to reinvent the wheel here. There is a need however to ask some good questions and get the unbiased answers. In my next couple of posts on this subject I will try to take a look at the timeline of research and with skepticism I will provide you with the evidence I find. With the evidence out there, I don't see a reason we don't have a universally accepted guideline for clinically clearing the cervical spine in the prehospital environment. Liability is unfortunately the most-likely answer to a question like this one--not science.

The 1999 study mentioned in part one listed Michigan and Maine as cohorts that implemented the criteria they studied for the use of spinal immobilization depending on mechanism of injury. After a couple go-arounds with Google, I found the 2005 edition of the Spinal Injury Assessment and Immobilization guideline of the Southeast Michigan Regional Protocol. I was able to find Maine's 2002 protocol, post NEXUS, and found it very interesting. I am going to get into those in a further post to stay chronological.

I want to take a look at some literature I found from the AANS & CNS that was done just after the turn of the new century. This was done prior to the NEXUS study (I will get into this study later) so NEXUS didn't make the 101 reference list. That's right, there is really 101 references, consisting of research from 1966 to 2001.

Right from the get-go[1]:

Standards: There is insufficient evidence to support treatment standards.
Guidelines: There is insufficient evidence to support treatment guidelines.

In the 101 references they listed, they couldn't find enough evidence to support treatment standards or guidelines. Almost 40 years of research, no sufficient evidence--amazing! Give me time and I will go through their references, but for now lets take a further look at what this paper has to say.

Options:

• It is suggested that all trauma patients with a cervical spinal column injury or with a mechanism of injury having the potential to cause cervical spinal injury should be immobilized at the scene and during transport using one of several available methods.

• A combination of a rigid cervical collar and supportive blocks on a backboard with straps is very effective in limiting motion of the cervical spine and is recommended. The longstanding practice of attempted cervical spinal immobilization using sandbags and tape alone is not recommended.

They have insufficient evidence to support treatment or guidelines, but they promote a treatment that they have guide-lined. I am being critical of the literature so far, but this next statement gives me good reason:

The chief concern during the initial management of patients with potential cervical spinal injuries is that neurologic function may be impaired due to pathologic motion of the injured vertebrae. It is estimated that 3% to 25% of spinal cord injuries occur after the initial traumatic insult, either during transit or early in the course of management.

Okay, I agree that we should be concerned with causing further harm or injury to our patients. Where do they get their estimate from regarding post-incident spinal cord injuries? They list 6 of there citations after that statement. 3% to 25% is a big margin, and to think that a quarter of all spinal cord injuries could be caused by first responders is scary. It may not be impossible, but I feel this is very unlikely. They then state that multiple cases have been reported where mishandling of the cervical spine lead to injury; they list 4 of there references after that one.

In the same paragraph the paper attributes neurological improvement of the spinal cord injured patients over the last 30 years to EMS. This conclusion was made after they state that in the 1970's, 55% of spinal cord injuries presented with complete lesions and in the 1980's, 61% had incomplete lesions. This is pretty interesting as well, and might lead to one of the answers to a seemingly easy question.

Where is the proof that spinal immobilization even works?

-Rogue Medic

It would be extremely difficult to show that without the implementation of full spinal immobilization a patient would suffer further injury. It is enlightening to read that there has been noticeable improvement since the implementation of prehospital spinal precautions. In further parts of this discussion I will revisit this question because it is a good one and deserves more than a one paragraph answer.

Back to the study in question:

Recently, the use of spinal immobilization for all trauma patients, particularly those with a low likelihood of traumatic cervical spinal injury has been questioned. It is unlikely that all patients rescued from the scene of an accident or site of traumatic injury require spinal immobilization.

They follow this up footnoting four of their citations and a statement regarding a triage-based criteria to determine appropriateness of immobilization. This is exactly what we are looking for. I wish they would have elaborated more in this paper though. Here is an abstract from one of the listed references[2]:

OBJECTIVE: To examine the effect of emergency immobilization on neurologic outcome of patients who have blunt traumatic spinal injuries. METHODS: A 5-year retrospective chart review was carried out at 2 university hospitals. All patients with acute blunt traumatic spinal or spinal cord injuries transported directly from the injury site to the hospital were entered. None of the 120 patients seen at the University of Malaya had spinal immobilization during transport, whereas all 334 patients seen at the University of New Mexico did. The 2 hospitals were comparable in physician training and clinical resources. Neurologic injuries were assigned to 2 categories, disabling or not disabling, by 2 physicians acting independently and blinded to the hospital of origin. Data were analyzed using multivariate logistic regression, with hospital location, patient age, gender, anatomic level of injury, and injury mechanism serving as explanatory variables. RESULTS: There was less neurologic disability in the unimmobilized Malaysian patients (OR 2.03; 95% CI 1.03-3.99; p = 0.04). This corresponds to a less than 2% chance that immobilization has any beneficial effect. Results were similar when the analysis was limited to patients with cervical injuries (OR 1.52; 95% CI 0.64-3.62; p = 0.34). CONCLUSION: Out-of-hospital immobilization has little or no effect on neurologic outcome in patients with blunt spinal injuries.

I'm not going to lie, the first thing I always read in these abstracts is the conclusion. Read the conclusion to this one. Doesn't that statement contradict a couple points we just mentioned. How this same paper attributes neurological improvement to EMS, and how immobilization is a vital part of the treatment rendered by EMS. Looks like we revisited Rogue Medic's question earlier than expected. Before we do, I want to look at a few more of this paper's references to see what we can find[3].

OBJECTIVE: To determine whether EMS providers can accurately apply the clinical criteria for clearing cervical spines in trauma patients. METHODS: EMS providers completed a data form based on their initial assessments of all adult trauma patients for whom the mechanism of injury indicated immobilization. Data collected included the presence or absence of: neck pain/tenderness; altered mental status; history of loss of consciousness; drug/alcohol use; neurologic deficit; and other painful/distracting injury. After transport to the ED, emergency physicians (EPs) completed an identical data form based on their assessments. Immobilization was considered to be indicated if any one of the six criteria was present. The EPs and EMS providers were blinded to each other's assessments. Agreement between the EP and EMS assessments was analyzed using the kappa statistic. RESULTS: Five-hundred seventy-three patients were included in the study. The EP and EMS assessments matched in 78.7% (n = 451) of the cases. There were 44 (7.7%) patients for whom EP assessment indicated immobilization, but the EMS assessment did not. The kappa for the individual components of the assessments ranged from 0.35 to 0.81, with the kappa for the decision to immobilize being 0.48. The EMS providers' assessments were generally more conservative than the EPs'. CONCLUSION: EMS and EP assessments to rule out cervical spinal injury have moderate to substantial agreement. However, the authors recommend that systems allowing EMS providers to decide whether to immobilize patients should follow those patients closely to ensure appropriate care and to provide immediate feedback to the EMS providers.

Interestingly enough, this study contradicts statements made in a study in my first post on this subject. The research in the other study concluded that emergency physicians and EMTs disagreed on the matter of cervical spine immobilization. This is a moot point by now because it doesn't prove or disprove anything. Whether EMTs and physicians agree or not does not reflect the efficacy of a prehospital spinal clearance protocol. This next abstract is promising[4]:

OBJECTIVE: To determine whether paramedics can safely use a spinal clearance algorithm to reduce unnecessary spinal immobilization (SI) in the out-of-hospital setting. METHODS: Paramedics were instructed in the use of a spinal clearance algorithm that prompted assessment of the trauma patient's 1) level of consciousness, 2) drug and/or alcohol use, 3) loss of consciousness during the event, 4) presence of spinal pain/tenderness, 5) presence of neurologic deficit, 6) concomitant serious injury, or 7) presence of pain with range of motion. The algorithm indicated that if any of the above were present, the patient should receive full SI, and if all of the above were negative, then SI could be withheld. Paramedics completed a tracking form that included the above and followed the patient to the emergency department (ED). Data were then gathered to determine the presence of spinal fracture, neurologic deficit, or a combination of the two. To compare the trends for SI, a retrospective medical incident report (MIR) review was conducted from the previous year. MIRs were selected based on the same criteria as those used for study inclusion. RESULTS: Two hundred eighty-one patients were included in the study, with 65% (n = 183) of them receiving SI. Two hundred ninety-three MIRs were included in the retrospective sample, with SI being provided 95% (n = 288) of the time. Comparison of these samples shows a 33% reduction in utilization of SI (95% confidence interval: 27.2%- 38.8%). CONCLUSION: An out-of-hospital spinal clearance algorithm administered by paramedics can reduce SI by one-third. Any application of a spinal clearance algorithm should be accompanied by rigorous medical supervision.

I'm sorry if this is turning into a post full of abstracts but this one in-particular is the first one I have read that was conducted before the year 2000 and shows positive results using a prehospital spinal clearance algorithm. This evidence was available prior to the statements made in that Trauma.org article, and could have been cited. I am going to stop criticizing Trauma.org for the rest of this discussion because I think I have proved my point. However, we have gone beyond that and into a greater discussion.

So far, what I have...

Prior to 2002 there has been much scrutiny in regards to the prehospital clearance of the cervical spine. There has been bold statements made by prestigious organizations to emphasize this point. There has been plenty of research on the topic, and as always, it is very contradictory. The question on why to immobilize patients in the first place has been touched on, but we haven't completely answered it yet. We also have some evidence that EMTs are capable of agreeing with emergency physicians on this subject--go figure. I have about 200 more references to sift through, and hopefully I can create a pretty elaborate timeline to show you where we have been and where we are. I have yet to share the conclusive evidence on this matter, but it is coming! Hopefully this will be developed into a universally accepted guideline, since it is somewhat accepted already by many prehospital agencies. I am also going to share some of the protocols from these agencies and hopefully some post-implemented research.

I'm going to take a pause with this literature for now and I will be revisiting it in the near future because some of the other subtopics in this discussion are brought up in this paper. In the next part I am going to take a look at the infamous NEXUS study and PHTLS recommendations. To take part in a current discussion on this post please visit EMTcity.com. I list that forum a lot just because it is the one I actually enjoy posting on. Also, please provide your commentary right here if you have any. I use your comments when authoring these posts.

Works cited

[1]American Association of Neurological Surgeons and the Congress of Neurological Surgeons. "Pre-hospital cervical spinal immobilization following trauma. Sept 2001 The PDF

[2]Hauswald M, Ong G, et al: Out-of-hospital spinal immobilization: Its effect on neurologic injury (comments). Academic Emerg Med 5:214-219,1998.

[3]Brown LH, Gough JE, et al: Can EMS providers adequately assess trauma patients for

cervical spinal injury? Pre-Hospital Emergency Care 2:33-36,1989. Pubmed abstract

[4]Muhr MD, Seabrook DL, et al: Paramedic use of a spinal injury clearance algorithm
reduces spinal immobilization in the out-of-hospital setting. Pre-Hospital Emergency Care
3:1-6,1999.