Challenging the dogma of spinal immobilization and other evidence from the Prehospital Evidence-based Practice (PEP) program
by Jennifer Greene, Jolene Cook, Ed Cain, Judah Goldstein, Jan Jensen1, Janel Swain, Dana Fidgen, Alix Carter.
Spinal trauma can be a devastating injury, frequently managed by prehospital clinicians. Recognition of a potential spinal cord injury and prevention of any further injury are paramount for appropriate emergency care. Clinical care may include assessment with structured clinical rules, application of cervical collars and long spinal board. Recommended practices may vary from region to region, and guidelines have changed over the last several decades, including in the recent publication of the 2015 ILCOR Consensus on Science and Treatment Recommendations.
Restriction of spinal movement was at one time a cornerstone of the prehospital management of these patients, but this is now falling out of favour. Indeed, Emergency medical services (EMS systems around the world vary greatly in the interventions being applied in the out- of-hospital environment for many clinical conditions). Also, interventions that were once thought to be “best practice” or standard of care later fell out of favour. Commonly, paramedics ask why an intervention is being applied in one setting but isn’t being done in another, or why we were trained to “always” do something, and then years later it is taken out of the protocols. An example of this is the care of patients with spinal cord injuries; for example, Australia has used spinal immobilization devices only for extrication for many years whereas for many other EMS systems, spinal immobilization for suspected spinal injury has become synonymous with the mandatory use of the long spine board.1 The question of spine boards becomes even murkier if you consider that the concept of spinal immobilization with a spine board is based on a few cases of delayed recognition of spinal cord injuries in the 1960s!
As the body of research evidence for prehospital clinical care continues to grow, it is important for prehospital clinicians and leaders to have a resource to quickly find prehospital-relevant research that can inform clinical care. This is particularly needed for topics such as spinal trauma, when best practices and guidelines change over time and the evidence is of varying quality with conflicting results. The issue is that up until recently there was very little research being done in the out- of-hospital environment to help guide decisions like the use of the spine board and many others. However nowadays, there is an exponentially expanding body of EMS evidence with conflicting results and of varying quality such that interpreting the evidence is tricky. This is where the Prehospital Evidence-based Practice (PEP) program becomes extremely valuable.
What is the Prehospital Evidence- based Practice (PEP) Program?
PEP (https://emspep.cdha.nshealth.ca/) is a robust online EMS resource that can help inform clinical practice regarding any patient presentation. The PEP Program aims to be the foremost evidence resource informing EMS. PEP is run by the Dalhousie University Department of Emergency Medicine, Division of EMS, in Halifax Nova Scotia, Canada.
Using systematic approaches PEP synthesizes EMS-relevant research in an open-access format. Available evidence is searched, selected, appraised and synthesized in simple, easy to understand evidence matrices. PEP can shorten the knowledge- to-practice gap and ensure prehospital clinical practice is based on current sound evidence. PEP assists users by reducing or eliminating the need to search for research studies on prehospital clinical care. Since PEP was introduced in 1998, the PEP database has exponentially grown with studies relevant to prehospital clinical care. PEP is also useful to identify gaps where more evidence is needed to help better inform prehospital clinical practice.
The PEP program essentially helps you skip doing an extensive literature review for clinical questions by systematically identifying, cataloging and appraising relevant EMS studies and then providing an overall summary of the evidence for each clinical intervention.
PEP search and appraisal methods are updated as needed, in order to ensure the rigor and validity of PEP recommendations, and reduce potential bias.
How can I use PEP to help me understand the evidence behind my clinical practice??
Within the PEP website, evidence is sorted by broad ‘Nature of Complaint’ categories (e.g., Major Trauma) then into, for example Shock, or Trauma. Next, a list of Clinical Conditions (e.g, Spinal Trauma) is presented. For example, under Trauma you would find Abdominal trauma, or Spinal trauma. When the user clicks the name of a Clinical Condition, an evidence matrix is displayed, with each intervention plotted in a table, indicating the Level of Evidence (LOE) (table 1) and Direction of Evidence (DOE) (table 2).
Evidence is described by Level (or quality) of Evidence, with 1 being strong, 2 being moderate and 3 being weak evidence (seeTable 1 ) and then also by Direction of Evidence, such that the evidence is summarized as to whether it supports, is neutral, or opposes the intervention (Table 2).
If you click on an intervention within the matrix (or scroll down) you will come to the individual papers that have been appraised for this topic. Each paper is also assigned a Level and Direction of Evidence. The matrix recommendation is a summary of the Level and Direction of all the individual papers for that intervention. You can reach the Pubmed (Medline) abstract by clicking on the individual citation.
What does PEP tell us about the care of spinal trauma patients?
The Spinal Trauma search was most recently updated in January 2016 using a systematic strategy developed with the help of a health sciences librarian. We used the following Population–Intervention-Comparison- Outcome (PICO) question as the base for our search: In (P) prehospital patients of any age who have experienced suspected spinal trauma, does the use of (I) (a list of individual interventions) result in improved/ neutral/worse (O) outcomes? A single author (JG) screened the list at the title and abstract levels for relevance, and two senior appraisers assessed the full text. The reference lists of all included studies and recent position papers on the topic were reviewed as well for other relevant citations. We included any primary research or systematic review reporting on emergency care of suspected blunt and penetrating spinal trauma. Emergency Department and simulation studies were included as they can inform EMS practice, but primarily the search was directed at answering the question of whether this intervention should be conducted in the prehospital/EMS/ Ambulance/Paramedic setting. The 2016 update added 45 new studies to our list of 33 publications already present in the PEP database, for a total of 77 papers.
Evidence for adult and paediatric blunt spinal trauma interventions was made up primarily of supportive-moderate quality evidence and neutral-moderate and high- quality evidence (Table 3 & 4). (Accessed on May 20th, 2017 https://emspep.cdha. nshealth.ca/LOE.aspx?VProtStr=Spinal Injury&VProtID=222). No evidence was identified for or against the use of hypertonic saline in spinal trauma.
It is clear that there is a growing body of research to inform EMS spinal trauma care. Let’s review the green (supportive) evidence identified in PEP. Some commonly used interventions were supported by evidence: cervical-spine clearance, scoop stretcher, self-extrication, spinal precautions (fair quality evidence), and “leaving helmet in place” (weak quality evidence).
C-spine clearance now contains 20 individual research papers. There is supportive evidence that C-spine clearance rules, such as the Canadian C-Spine rule, are able to reduce the need for imaging while being able to identify clinically important injuries in the prehospital environment.
You may notice a number of studies have been assigned a neutral classification. In PEP, studies performed in non-EMS settings can be moved to neutral due to indirectness if the setting likely affected the results such that we wouldn’t expect the same result in an EMS setting (see Stiell et al. 2009). The primary outcome for the majority of these studies was the ability of the rule to identify those who did have a spinal injury compared to the ability of the rule to identify those who truly did not have an injury.
Shifts in practice
Two of the interventions in the 3×3 matrix should jump out as a shift from the usual dogma of practice: steroids, and long spinal immobilization. These two examples really demonstrate how evidence can shift practice. A few early studies were very promising about the use of steroids, particularly whether there is benefit to giving them in the ambulance or prehospital setting. As many leading organizations now recommend, the balance of evidence in PEP on steroid use in the context of spinal trauma suggests the harms may not outweigh the benefits identified.
Until recently, long spinal boards were the accepted way to package and transport a suspected spinal injury. However, they were originally designed as extrication devices and not as transport mechanisms. Evidence is emerging that the practice of maintaining a patient on a long spinal board for the duration of transport and until they can be log-rolled and cleared off the board may be resulting in more harm than benefit. Leading organizations are now looking at this evidence and calling on emergency services to stop the use of this intervention as a prolonged immobilization and transport device.
There is evidence that this intervention causes harm with regard to tissue interface pressures, which can ultimately result in pressure sores. Another important outcome is patient (or volunteer) reported discomfort. There is one high quality paper, four moderate quality papers and six weak quality papers opposing this intervention. For quite a long time this was an intervention we just accepted as “the way things are done”, but the evidence strongly challenges this practice. In fact, only one paper showed any benefit in the use of spine board in preventing cervical motion during transport with several other papers showing that there wasn’t any benefit at all. For all of these reasons, many EMS systems have stopped using long spine boards except when necessary for patient extrication.
Overall, the evidence for EMS interventions in spinal injuries was neutral, in other words neither supported nor opposed, for inline stabilization during intubation, steroids, and cervical collars. The evidence was opposing the use of long spine board immobilization, short extrication devices and immobilization for penetrating trauma.
Limits of the evidence
The most common primary outcomes identified were spinal motion, diagnostic accuracy, and pressure/discomfort. There are not many studies that report on actual worsening of spinal cord injury or long term functional status, which would ultimately be the most important outcome. Instead many studies use these proxy measures as they are easier to obtain and can be done on healthy volunteers (for example spinal motion, discomfort).
A number of studies in the spinal trauma section were completed in non-EMS settings such as emergency departments. In these cases, the direction of recommendation is downgraded if it was felt that the intervention would be affected by the setting or health care provider applying the intervention. One particular limitation to note is that many spinal trauma studies were performed in healthy volunteers using motion sensors in order to identify the effects of spinal immobilisation techniques on motion restriction. These studies in combination with the growing body of evidence on the negative outcomes of spinal immobilisation contributed to where interventions were placed within the evidence matrix.
Steroids were the only medication identified within the spinal injury section.
Implications to research
PEP also exposes gaps in the current research, and can help researchers determine what studies should happen next. One gap in the evidence for spinal trauma is the lack of sufficient evidence to make a recommendation about the use of hypertonic saline. Certainly the use of proxy measures such as spinal movement detected by sensors on health volunteers is also a gap; it would be ideal to have evidence on actual long term recovery of real patients. However, it is not always feasible or ethical to expose real patients to uncertain interventions just to study the difference between the outcomes, and so we make the best decisions with the evidence we have.
Clinical bottom line
The clinical bottom line supported by the synthesis of the currently available evidence on spinal trauma is that there is evidence to support EMS clearance of C-spine, use of scoop stretcher, self-extrication, spinal precautions, and leaving the helmet in place. The evidence opposes immobilizing patients with penetrating trauma, and use of short extrication devices. Most interestingly, the evidence is not supportive of using long spinal immobilization devices or steroids, and these practices are now being discontinued in many EMS services around the world.
PEP can be used as a quick link to a synthesis of existing evidence for many of the questions paramedics, administrators, medical directors, and other professionals involved in EMS systems might have about clinical care provided in the EMS environment.