Trauma Reports EVIDENCE-BASED MEDICINE EOR THE ED Volume 14, Number 1 Jan/Feb 2013 Authors: Kim Boswell, MD, Fellow, Trauma Critical Care, University of Maryland, Baltimore, MD. Jay Menaker, MD, Associate Professor, Departments of Surgery and Emergency Medicine, University of Maryland School of Medicine, Baltimore, MD. Peer Reviewer: Robert E. Falcone, MD, FACS, Clinical Professor of Surgery, The Ohio State University, Professor of Clinical Surgery — Affiliate Faculty, University of Cincinnati. Statement of Financial Disclosure To reveal any potential bias In this publication, and In accordance with Accreditation Council for Continuing Medical Education guidelines, we disclose that Dr. Dietrich (editor in chief). Dr.'Boswell (author). Dr. Menaker (author). Dr. Falcone (peer reviewer), and Ms. Behrens (nurse reviewer) report no relationships with companies related to this field of study. Ms. Mark (exec- utive editor), and Ms. Hanfilin (managing editor) report no relationships with companies related to the field of study covered by this CME activity. Media An Update on Spinal Cord Injury: Epidemiology, Diagnosis, and Treatment for the Emergency Physician A spinal cord injury can be devastating. The National Spinal Cord Injury Statistical Center (NSCISC) has been collecting epidemioloßic data on spinal cord injury (SCI) for nearly 40 years and has been able to provide the public and medi- cal community with information on the evolution of SCI, including demographics, injury patterns, long-term prognosis, and sodoeconomic impacts. There have been some interesting trends and significant changes to the data as time, technology, and culture have progressed. According to the NSCISC website, as of 2011, there are approximately 12,000 new cases of SCI annually. This figure does not include those who die from their injuries at the scene. It is believed that there are as many as 316,000people currently living with SCI in the United States.^ This article will provide an update of the recent literature and standard of care in the diagnosis and treatment of acute SCI. — Ann M. Dietrich, MD, Editor Epidemiology When data collected from the early 1970s are compared to current informa- tion, general trends are noted in age at time of injury and racial/ethnic distri- bution of SCI. In the early 1970s, SCI was a disease of young, Caucasian males with an average age in the late 20s, and close to 70% of those affected by SCI were Caucasian, with 14% and 0.9% affecting African Americans and Asians, respectively. Since 2005, the trends demonstrate an older population being affected, with the average age at time of injury approximately 40.7 years old, likely a reflection of the increasing age of society. An appreciable increase in the incidence of SCI in the African-American and Hispanic populations has also been observed, with African Americans now accounting for close to 27% and Hispanics for 8.3% of all SCI reported annually. These changes are likely a result of the general changes in the country's population, as well as improved referral, documentation, and reporting methods throughout the country. Motor vehicle collisions (MVC) are persistently the most common cause of SCI and represent approximately 40.4% of all reported injuries. Falls (27.9%) are second to MVC, followed by violence (15.0%) and sporting injuries (8.0%). Interestingly, falls as an etiology of SCI appear to be increasing in prevalence, whereas sporting injuries are declining. As an etiology, violence peaked between 1990 and 1999 at a rate of 24.8%, but decreased in the following decade. From a social perspective, approximately half of patients are married at the time of their injury. Compared to national averages, these marriages are only slightly more likely to end in divorce or separation. Those individuals who are not married at the time of injury are slightly less likely, overall, to get married. Close to 58% of people are employed at the time of their injury. Not surpris- ingly, at the end of their flrst year following injury, only approximately 11.6%
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Trauma ReportsEVIDENCE-BASED MEDICINE EOR THE ED
Volume 14, Number 1 Jan/Feb 2013
Authors:Kim Boswell, MD, Fellow,Trauma Critical Care, University ofMaryland, Baltimore, MD.
Jay Menaker, MD, AssociateProfessor, Departments ofSurgery and Emergency Medicine,University of Maryland School ofMedicine, Baltimore, MD.
Peer Reviewer:Robert E. Falcone, MD, FACS,Clinical Professor of Surgery, TheOhio State University, Professorof Clinical Surgery — AffiliateFaculty, University of Cincinnati.
Statement of Financial DisclosureTo reveal any potential bias In this publication, and Inaccordance with Accreditation Council for ContinuingMedical Education guidelines, we disclose that Dr.Dietrich (editor in chief). Dr.'Boswell (author). Dr.Menaker (author). Dr. Falcone (peer reviewer), and Ms.Behrens (nurse reviewer) report no relationships withcompanies related to this field of study. Ms. Mark (exec-utive editor), and Ms. Hanfilin (managing editor) reportno relationships with companies related to the field ofstudy covered by this CME activity.
Media
An Update on Spinal Cord Injury:Epidemiology, Diagnosis, andTreatment for the Emergency
PhysicianA spinal cord injury can be devastating. The National Spinal Cord Injury
Statistical Center (NSCISC) has been collecting epidemioloßic data on spinal cordinjury (SCI) for nearly 40 years and has been able to provide the public and medi-cal community with information on the evolution of SCI, including demographics,injury patterns, long-term prognosis, and sodoeconomic impacts. There have beensome interesting trends and significant changes to the data as time, technology,and culture have progressed. According to the NSCISC website, as of 2011, thereare approximately 12,000 new cases of SCI annually. This figure does not includethose who die from their injuries at the scene. It is believed that there are as manyas 316,000people currently living with SCI in the United States.^ This article willprovide an update of the recent literature and standard of care in the diagnosisand treatment of acute SCI.
— Ann M. Dietrich, MD, Editor
EpidemiologyWhen data collected from the early 1970s are compared to current informa-
tion, general trends are noted in age at time of injury and racial/ethnic distri-bution of SCI. In the early 1970s, SCI was a disease of young, Caucasian maleswith an average age in the late 20s, and close to 70% of those affected by SCIwere Caucasian, with 14% and 0.9% affecting African Americans and Asians,respectively. Since 2005, the trends demonstrate an older population beingaffected, with the average age at time of injury approximately 40.7 years old,likely a reflection of the increasing age of society. An appreciable increase in theincidence of SCI in the African-American and Hispanic populations has alsobeen observed, with African Americans now accounting for close to 27% andHispanics for 8.3% of all SCI reported annually. These changes are likely a resultof the general changes in the country's population, as well as improved referral,documentation, and reporting methods throughout the country.
Motor vehicle collisions (MVC) are persistently the most common cause ofSCI and represent approximately 40.4% of all reported injuries. Falls (27.9%)are second to MVC, followed by violence (15.0%) and sporting injuries (8.0%).Interestingly, falls as an etiology of SCI appear to be increasing in prevalence,whereas sporting injuries are declining. As an etiology, violence peaked between1990 and 1999 at a rate of 24.8%, but decreased in the following decade.
From a social perspective, approximately half of patients are married at thetime of their injury. Compared to national averages, these marriages are onlyslightly more likely to end in divorce or separation. Those individuals who arenot married at the time of injury are slightly less likely, overall, to get married.Close to 58% of people are employed at the time of their injury. Not surpris-ingly, at the end of their flrst year following injury, only approximately 11.6%
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Executive Summary• Since the injury to the cord is bilateral for anterior
cord syndrome, the pattern of symptoms that accom-panies this injury includes bilateral motor paralysis andloss of pinprick, temperature, and pain sensation belowthe level of injury. Since tJie posterior aspect ofthecord is preserved, so is proprioception and vibratorysensation.
• Classic Brown-Séquard syndrome, in its purest form,is described as a loss of ipsilateral motor function, pro-prioceptúon, vibratory and pressure sensation, and con-tralateral loss of temperature and pain sensation belowthe level of injury.
• Of all cord syndromes, Brown-Séquard syndrome hasthe best overall prognosis, with more tJian 80-90%of people recovering bowel and bladder function andmore tJian 75% regaining their ambulatory status.
• The most common of all partial cord syndromes iscentral cord syndrome, which is distinguished fromthe other cord syndromes by the fact that the upperextremities are significandy more affected from themotor perspective than tJie lower extremities.
remain employed. Optimistically, thisnumber increases to 35.2% after 20years and holds steady for data col-lected after 30 years post-injury.
Spinal Cord Injury ModelSystem Program
In the 1970s, the NationalInstitute on Disability andRehabilitation created the SpinalCord Injury Model System Programthrough federally funded grants.The model systems are composed of14 major medical institutions andthree subcontracted facilities, whichfocus on the treatment of spinal cordinjury, traumatic brain injury (TBI),and burn injury. The purpose is thecollection of information and to con-duct research surrounding the reha-bilitation, long-term outcomes, andcomplications of SCI, TBI, and burninjuries, in addition to social aspectsincluding health, Wellness, and ser-vice delivery. Over the years, themodel systems have provided a greatdeal of information about spinal cordinjury, rehabilitation, and outcomes.^
Based on the 2011 National SpinalCord Injury Database figures, thelifetime costs associated with SCIdepend upon the severity/levelof injury and the age at which theinjury is sustained. The first yearfollowing the injury is always associ-ated with a greater cost than sub-sequent years. It is estimated thata high quadriplegic (C1-C4) willexpend approximately $985,000in the first year alone, followed by
approximately $171,000 annually.Injuries occurring earlier in life athigher spinal cord levels require themost financial expense. High quad-riplegia sustained at age 25 resultsin an estimated $4.3 million lifetimeexpense, whereas the same injurysustained at age 50 is estimated tocost approximately $2.4 million.Lower cervical SCI and SCI resultingin paraplegia, on average, cost lessfor both the first year of treatmentas well as for lifetime associated cost.{See Table 1.)
Grading ScalesThere are two well-known scales
used to grade and prognosticate SCI.The Frankel scale was developedduring World War I, but is less com-monly used today. It is a basic scalethat grades the SCI based on leveland is used to evaluate functionalrecovery. There are five grades usedin the Frankel scale, which essentiallydivide complete versus incompletespinal injuries as follows:
• A — complete paralysis (nomotor/sensory below level ofinjury);
• B — sensory present below levelof injury;
• C — incomplete injury withmotor and sensory function belowlevel of injury;
• D — fair to good motor functionbelow level of injury; and
• E — normal function (no motorof sensory deficit).^
The American Spinal Injury
Association (ASIA) ImpairmentScale (AIS) is a more widely usedand more refined scale. Based on theFrankel scale's five grading levels, theAIS was originally developed in 1982and has undergone six revisions, withthe most recent occurring in 2002.The AIS differs from the Frankelscale in that it more clearly definescomplete and incomplete injury bydetermining sacral sparing (presenceof rectal motor function or sensoryfianction at S4-S5 dermatome),determining the presence of neuro-logic level of injury using sensoryand motor evaluation in bilateralextremities, and by determining, inincomplete injuries, where partialzones of sensory or motor preserva-tion exist.
Practically, the ASIA is a scale thatscores motor and sensory functionon different scales. There is alsoa letter that is assigned based ondegree of motor, sensory, and/orpresence of sacral function. Althoughfor completeness sake the motorand sensory scales are important inthe evaluation of an acute SCI, froma functional perspective, the lettergrade is most often used and conveyssubstantial information.
The motor scale is a 100-pointscale that uses 10 muscle groups(five groups in the upper extremi-ties and five in the lower) that aretested bilaterally. It is important torecognize that the muscle strengthis not what is tested, but rather therange of motion. Range of motion is
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Table 1. Economic Impact of SCI
Severity of Injury
High Tetraplegia(C1-C4)
Low Tetraplegia(C5-C8)
Paraplegia
Incomplete MotorFunctional at Any
Level
Average Yearly Expenses(in 2010 dollars)
First Year
$985,774
$712,308
$480,431
$321,720
Each Subsequent Year
$171,183
$105,013
$63,643
$39,077
Estimated Lifetime Costs by Age at Injury(discounted at 2%)
25 years old
$4,373,912
$3,195,853
$2,138,824
$1,461,255
50 years old
$2,403,828
$1,965,735
$1,403,646
$1,031,394
Data Source: Economic impact of SCI, 7op/cs in Spinal Cord Injury Rehabilitation 2011;16(4).
scored using the standard 0-5 pointscale, with 0 indicating no move-ment and 5 indicating movementagainst frill resistance. Assessmentof strength in each motor groupinstead of range of motion acrossthe joint can lead to inappropriatelyhigh scores that wül inevitably over-estimate the final motor score and,therefore, final ASIA score. A motorindex score of 100 is evidence ofno motor deficit, or a normal exam.The motor level is defined as thelowest level at which there is 3 /5movement.
The sensory grading system is a112-point scale that tests 28 derma-tomes bilaterally for both light touchand pinprick sensation. The sensorylevel is defined as the most caudallevel with normal light touch andpinprick sensation. Again, a sensoryindex score of 112 demonstrates anormal sensory examination. (SeeTable 2.)
Complete injuries are those inwhich there is no motor or sensoryfiinction below the level of injury.Specifically, AIS A injuries are thosein which tbere is no sacral motorfianction or sensation. Incompleteinjuries are grades B, C, or D,and the specific letter assignmentdepends on the presence of motor,sensory, or grade of muscle strength.AIS E is a normal neurologic examwith no deficits appreciated. Zoneof partial preservation is a term only
applied in complete SCI (those inwhich there is no sacral motor orsensory function) and describes areasof preserved segments below theneurologic level of injury.
The AIS may suggest the poten-tial for minimal to some neurologicrecovery, but has not been validatedas a true prognostic scale. It does,however, provide the medical com-munity with a common language tocommunicate the severity and levelof SCI and, for this reason, in addi-tion to the thoroughness of the AIS,it has been adopted by the majorityof major medical intuitions bothnationally and internationally.*
PathophysiologyThe normal structure, neuropro-
tective mechanism, and metabolismof the spinal cord are interrupted asa result of injury. There are manytheories on the pathophysiology ofthe spinal cord following injury, butmost theories include the belief thatthere are two main phases of evolu-tion, primary and secondary injury,and it is likely that the actual pro-cess encompasses components of alltheories. The progression of injury isbelieved to occur over the course ofthe first week, but successive histo-logie changes can be seen as far outas one month following injury.
Normally, the gray matter of thespinal cord has a much higher rateof metabolism and contains the
neuronal bodies directly within thetissue itself, as opposed to the whitematter that has a slower metabolicrate and contains its neuronal bodiesat distant sites. This difference makesthe gray matter more susceptible toinjury than the white matter.
Primary injury occurs at the timeof the initial insult and can be eitherpenetrating or blunt. Primary injuryto the spinal cord is commonly dueto trauma and affects the cord levelat which the trauma occurs. Primaryinjury also occurs to neighboringlevels adjacent to the primary sitesecondary to edema, hemorrhage,concussive, stretching, or shearingforces and ischemia.
In the minutes, hours, and firstseveral days following SCI, metabolicchanges take place in the spinal cordthat are believed to lead to second-ary injury. It is at this point that themany theories on SCI diverge. Afrerdirect injury to the cord, there is aperiod of inflammation that occurswithin the gray and white matter,which leads to the metabolic and bio-chemical changes that can be toxic tothe spinal cord tissue, leading to fur-ther damage. Following spinal cordinjury, clinically it is not uncommonto have hypotension and bradycardiaas a result of autonomie dysflinction,which can contribute to decreasedcord perfiision and, ultimately,continued cord damage. Althoughthere are many theories that describe
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Table 2. ASIA ScalelGrading
AIS Impairment Scale
A
B
C
D
E
Complete — Absence of motor and sensory function insacral segments (S4-S5)
Incomplete — Preserved sensory function, but absentmotor function below neurologic level of injury. Sacralsensation intact (S4-S5)
Incomplete — Preserved motor function below neurologiclevel of injury. More than half of muscle groups belowinjury have muscle grade of 3 or less.
Incomplete — Preserved motor function below neurologiclevel of injury. More than half of muscle groups belowinjury have muscle grade of 3 or greater
Normal Examination — No motor or sensory deficits
different biochemical complicationsas a result of injury, they all concludethat ultimately a cascade of toxicmediators (excitatory amino acids,free radicals, or calcium ions, forexample) results in neuronal ceU dam-age and death propagating secondaryspinal cord injury.^
Spinal Cord SyndromesThe anatomy of the spinal cord
must be appreciated to identify thepatient's specific spinal cord syn-drome. Patterns of symptoms cangive the examiner an idea of theinjury sustained, prognosis, and out-come even prior to imaging.
The spinal cord is divided intotracts. These tracts contain bundlesof nerve fibers that run together ineither an ascending or descendingfashion, cross over the spinal cordin varying locations, and have clini-cally and characteristically significantfindings when damaged. There arethree particular tracts of the spinalcolumn that are critically important.The dorsal column is an ascending,ipsilateral tract that is located in theposterior aspect of the cord and con-tains information on proprioceptionand vibration. The corticospinal tractis a descending,, ipsilateral motortract. Lastly, the spinothalamic tractis an ascending, contralateral tractthat contains pain, temperature, andlight touch nerve fibers.
Anterior Cord SyndromeAnterior cord syndrome is usu-
ally sustained due to a hyperñexioninjury to the cervical cord, butcan occur anywhere in the spinalcolumn. Hyperflexion of the cordcauses direct contusion to the cordor can result in the protrusion of disccontents, bony fragments that havefractured, or, rarely, can cause directlaceration or thrombosis to the ante-rior spinal artery. Since the injury tothe cord is bilateral, the pattern ofsymptoms that accompany this injiuyincludes bilateral motor paralysisand loss of pinprick, temperature,and pain sensation below the level ofinjury. Since the posterior aspect ofthe cord is preserved, so is proprio-ception and vibratory sensation.
The overall prognosis for anteriorcord syndrome is poor. Improvementin motor function can be seen withinthe first 24 hours following injury,but usually does not occur after thefirst day. After 30 days followinginjury, there is little to no additionalrecovery of function.*
Brown-SéquardSyndrome
Brown-Séquard syndrome is ananatomic or functional hemisec-tion of the cord, which has severalpotential causes. From a traumaperspective, Brown-Séquard is com-monly the result of penetrating
trauma to the spinal cord. However,more commonly it is due to inherentspinal or compressive lesions suchas tumors or epidural hematomas.Classic Brown-Séquard syndrome,in its purest form, is described as aloss of ipsilateral motor function,proprioception, vibratory and pres-sure sensation, and contralateral lossof temperature and pain sensationbelow the level of injury. Althoughthe pure form of Brown-Séquardsyndrome is rarely seen, a partialform of Brown-Séquard is morecommon. Interestingly, because thefibers of the lateral spinothalamictract decussate one or two levelsabove or below where the injury mayoccur, it is possible to see ipsilateralpain and temperature sensory lossabove the level of injury.
Of all cord syndromes, Brown-Séquard syndrome has the bestoverall prognosis, with more than80-90% of people recovering boweland bladder function, and morethan 75% regaining their ambulatorystatus.^
Central Cord SyndromeThe most common of all partial
cord syndromes is central cord syn-drome, which is distinguished fromthe other cord syndromes by thefact that the upper extremities aresignificantly more affected from themotor perspective than the lowerextremities are. The most commonmechanism of injury is a hyperex-tension injury, and it is usually seenafter a fail in an older populationwith preexisting spinal stenosis orarthritis. The injury to the spinalcord affects the central portions ofthe corticospinal and spinothalamictracts, resulting in the disproportion-ate pattern of symptoms between theupper and lower extremities. Patientstypically have greater weakness inthe proximal muscles than in thedistal ones. Sensory symptoms arealso appreciable, with some patientspresenting with dysesthesias of theirupper extremities as their predomi-nant symptom.
The prognosis of central cord syn-drome is dependent upon the sever-ity ofthe cord contusion after injury
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and the age at the time of injury.Patients younger than 50 years oldat the time of injury tend to havemore significant bladder continencerecovery (80%) and achieve ambula-tory recovery (90%) as compared totheir older counterparts. Those olderthan 50 years at the time of injuryhave approximately a 50% chance ofregaining ambulatory ñinction, andonly 30% regain bladder continence.*
Acute Managementof SCI
The acute management of spinalcord injury occurs in several settings.In the prehospital setting, provid-ers must maintain a high index ofsuspicion for spinal injury when pre-senting on the scene of any motorvehicle collision, fall, assault, orvarious other mechanisms in whichinjury to the spinal cord, occult orobvious, may have occurred. As withany trauma, airway, breathing, andcirculation (the ABCs) always comefirst in the stabilization of a patient.In the event of high cervical spineinjuries, severe trauma, or head inju-ries in which the patient's respiratoryeffort, mental status, or ability tomaintain his/her own airway may becompromised, it may be indicatedto bring the patient to the closestlocal facility for airway protection.Inline cervical spine stabilizationshould be utilized in every traumapatient for intubation, regardless ofa high or low suspicion for SCI. Asingle person should be dedicated tomaintaining the integrity of spinalstabilization, while another is cau-tiously securing the airway. If a highsuspicion for cervical spine injuryexists, fiberoptic intubation, whenavailable, should be considered as thesafest means of intubation.
Proper prehospital precautionsinclude cervical spinal immobiliza-tion with a rigid cervical collar, fullspinal precautions, log-rolling, andtransporting patients on a backboard.Minimizing movement of the patientwhile still maintaining the ability toprovide care should be balanced.
Upon arrival in the hospital set-ting, ABCs should be reevaluatedand intervention at any step should
be taken to stabilize the traumapatient. The airway should besecured, while maintaining cervi-cal spine precautions, in any patientwith significant facial trauma, headinjury, or GCS less than 8. In thosepatients who are believed to have asignificant or isolated spinal injuryrequiring urgent rather than emer-gent intubation, consideration offiberoptic or other advanced methodof intubation is warranted. Patientswith high cervical spine injuries (C5and above) are at high likelihoodof requiring mechanical ventilationand should be closely monitored andconsidered for early intubation andairway control.'
A primary survey as part of atrauma evaluation should be rapidlybut thoroughly preformed. Part ofthe primary survey should includeexamination of the spine. With thepatient's cervical spine being prop-erly immobilized, the patient shouldbe log-rolled and the emergencyphysician should palpate the spinefor bony tenderness, obvious step-offs, or crepitus that would heightenthe suspicion for spinal injury. Thepresence of any of these findingsshould prompt the physician to per-form ñirther diagnostic evaluation. Ifnone of these exist and there are noconcerning neurologic findings, thebackboard can be removed.
Hemodynamic StatusIn evaluation of a patient's hemo-
dynamic status, sufficient vascularaccess should be obtained whilekeeping in mind additional injuries,which may limit optimal locationsfor access placement. What is con-sidered sufficient may vary basedon injuries sustained and present-ing hemodynamics and should bedetermined based on the physician'sclinical judgment. It is importantto remain vigilant to the fact thatmany spinal cord-injured individu-als develop a significant amount ofhemodynamic lability in the first fewhours, days, and even weeks follow-ing their injuries, and what seemssufficient may quickly become oth-erwise. The hemodynamic labilitywill often require vasoactive support
and, therefore, placement of centralvenous access and an arterial line arereasonable even if a patient is ini-tially stable. Frequent réévaluationof vital signs in a patient with SCI iswarranted.
Spinal Shock vs.Neurogenic Shock
Initial vital signs can vary depend-ing on an isolated spinal fracture orspinal cord injury or multi-systemtrauma. In a hemodynamically unsta-ble patient with what appears to beisolated spinal trauma, the medicalprovider should still be concernedabout and exclude additional internalinjuries, particularly abdominal inju-ries. Hypovolemic shock can presentsimilarly to spinal and neurogenicshock; however, the managementvaries considerably. Once other inju-ries have been excluded as the causeof shock (i.e., intra-abdominal bleed-ing, thoracic trauma, etc.), it is safeto attribute hemodynamic instabilityto acute spinal cord injury. In SCI,vital signs can vary dramatically aswell and can reflect two well-knownbut different entities: spinal shockand neurogenic shock.
Spinal Shock. Spinal shock is apresentation of acute SCI that occurswithin the first 24 hours followinginjury and describes a transient con-stellation of symptoms that includetotal loss of reflexes below the levelof injury, flaccid paralysis includingloss of rectal tone, and completeloss of sensation. These findings areoften accompanied by autonomiedysñinction, but spinal shock is nota hemodynamic phenomenon.'" Thepresence of priapism in a patientwith acute SCI is suggestive of spi-nal shock. There are several theoriesthat attempt to explain both thepathophysiology as well as define theduration of spinal shock. No clearconsensus exists, but many theoriessuggest that the end of spinal shockoccurs when the first reflexes return.Often, the first reflex to return isthe bulbocavernosus reflex. Despitethe lack of consensus on the patho-physiology and termination of spinalshock, all theories agree that spinalshock begins within 24 hours, and
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usually within minutes to hoursof the acute injury. Most theoriessuggest that spinal shock begins toresolve within 72 hours of onset, butthere are several schools of thoughtthat suggest termination based onthe return of deep tendon refiexesseveral weeks after injury or thereturn of detrusor function, whichcan take several months to recover. ' '
Neurogenic Shock. Neurogenicshock is a hemodynamic phenom-enon that is also associated withacute SCI. A classic triad of symp-toms including hypotension, brady-cardia, and peripheral vasodilation,secondary to a profound loss ofsystemic vascular resistance, is seen.Neurogenic shock is often referredto as "warm shock" because of thevasodilation, but as a result of thespinal injury, it is not uncommon forthese patients to be hypothermie.Onset is usually within 30 minutesof injury and can last several days toweeks following injury.'^ Neurogenicshock is most commonly seen inassociation with spinal cord injuryabove the level of T6, but can occurat any level. A recent study sug-gests that neurogenic shock is seenin approximately 19% of cervicalspinal injuries, 7% of thoracic spinalinjuries, and in only 3% of lumbarspine injuries.'^ As previously stated,any trauma patient with hypoten-sion should be quickly assessed toensure there is no alternative cause.Neurogenic shock should, there-fore, essentially be a diagnosis ofexclusion once hemorrhage andthoracic trauma have been effectivelyexcluded.
Treatment of shock in SCI isdependent upon identification ofspinal shock or neurogenic shock. Itis important to make the distinctionbetween the two in each individual,but to also keep in mind that asingle patient can have both condi-tions concomitandy. Treatment ofspinal shock is primarily support-ive. In contrast, the treatment ofneurogenic shock requires volumeresuscitation to help compensate forthe massive vasodilation that occurs,in addition to pharmacologie sup-port. Early use of vasopressors is
recommended to avoid fluid over-load, although no specific goal ofmean arterial or systolic blood pres-sures has been identified as optimal.Pharmacologie support in the formof vasopressors should be initiatedonce fluid resuscitation has failed toimprove the patient's hemodynamics.Norepinephrine should be used as afirst-line agent, followed by medica-tions like dopamine and dobutamine.Medications like phenylephrine, withunopposed alpha activity, should beavoided, given the pathophysiol-ogy of neurogenic shock and thepotential for reflexive bradycardia,which may further worsen the spinalcord injury. Atropine is used to treatbradycardia.'*
Overall, the goal of treating neuro-genic shock is the same as treatmentfor any form of shock: adequatetissue perfusion. Most importandy,however, treatment of neurogenicshock should be aimed at maintain-ing perfusion of the injured region ofthe spinal cord in hopes of minimiz-ing any additional secondary injury.
Neurologic EvaluationIn the patient with an acute spinal
cord injury, it is imperative to obtaina thorough neurologic evaluationas soon as possible. After initialstabilization, it is important to per-form the neurologic examination ascompletely as possible, fiilly assess-ing both motor and sensory deficits.Rectal sensation and tone are imper-ative in the neurologic evaluationof an acute SCI. All reflexes shouldbe evaluated, as they can provideimportant clues to diagnosing spinalshock. As previously described, theASIA scale is the most commonlyused and most widely acceptedscale for determining the extent ofneurologic injury in patients withSCI and should be performed at72 hours. The ASIA can be per-formed earlier, but in patients withspinal shock it may not be accurateand should be redone once reflexesreturn. Specifically, the diagnosis ofcomplete versus incomplete injury(AIS A versus B, C, or D) carmot bemade until spinal shock has resolved,and this diagnosis carries significant
implications for the patient'sprognosis.
PolytraumaIn patients with spinal cord injury
in the setting of additional injuriesor hemodynamic instability, it isreasonable to defer definitive treat-ment of the spinal cord injury untilother life-threatening injuries areaddressed (i.e., abdominal trauma/hemorrhage, or thoracic or cardiacinjury), assuming the cervical spineis properly immobilized using a hardcoUar and log-roll precautions areused when moving the patient.
Imaging of the SpineImaging of the spine in a trauma
patient can be accomplished usingplain films, computed tomography(CT), or magnetic resonance imag-ing (MRI). The type of imagingchosen by the emergency physicianshould be based on the physician'sclinical suspicion, level of risk stratifi-cation, or pretest probability for SCI.
In the past several decades, manystudies have evaluated close to 40,000patients with an asymptomatic cervi-cal spine examination. From thesestudies, class I evidence exists thatstates that in an asymptomatic patient,there is no benefit in obtaining cervi-cal spine imaging. In addition to thefact that imaging provides no benefitin the asymptomatic population, italso exposes patients to unneces-sary radiation, is costly to the medi-cal system, and utilizes unnecessaryresources. In 2001, the Congressof Neurological Surgeons and theAmerican Association of NeurologicSurgeons published the Guidelines forthe Management of Acute CervicalSpine and Spinal Cord Injuries, whichdefine an asymptomatic patient by thefollowing criteria:
• Neurologically normal (CCS 15,no focal motor or sensory deficits,appropriate response to externalstimuli, and appropriate orientation);• Free of intoxication or substances,which can alter a patient's level ofalertness;
• Absence of midline neck tender-ness from the nuchal ridge to thefirst thoracic vertebrae;
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• Absence of associated, distract-ing injury (including, but not limitedto a long bone fracture, large lacera-tions or degloving injuries, burns,or injuries that require surgicalconsultation).'^
In emergency medicine, thereare two clinical rules commonlyused to evaluate the cervical spinein patients with blunt trauma. TheNational Emergency X-RadiographyUtilization Study (NEXUS) used tiiesame criteria mentioned above to •evaluate patients with blunt traumaand demonstrated 100% sensitivityin excluding cervical spine trauma. Ifall of the criteria are met, the authorsrecommend that imaging not beperformed.'* The Canadian C-Spine(CCR) rule includes additional cri-teria, which more clearly risk stratifypatients based on the mechanismof injury, previous spinal disease orinjury, as well as clinical examinationfindings. Although a lengthier rule,the CCR may aüow for clearance ofcervical immobilization devices inpatients who may have otherwisekept the coUar based on NEXUS.'^
Alternatively, the symptomaticpatient is the patient with pain onexamination of the midline cervicalspine, an altered level of conscious-ness due to trauma or intoxication,or patients with neurologic deficit.These are the patients who shouldundergo radiologie evaluation priorto clearance of the immobilizationdevice. Plain radiographs are suf-ficient when three views are com-pleted and the radiograph qualityis optimal.'* Injuries may be missedin those who have suboptimal filmsthat do not adequately show theregion of injury. These missed inju-ries secondary to suboptimal imag-ing most commonly occur at highcervical levels (C2) as well as at thecervical-thoracic junction (C7-T1).The emergency physician knows thatin the acutely injured patient wearinga hard cervical collar, optimal plainfilms are often hard to obtain. Forthis reason, CT has been studied asan adjunct mode of imaging to plainradiographs and has been found tobe a cost-effective means of evaluat-ing for cervical spine injury."
Computed tomography of thespinal column has been shown to bean efficient and sensitive modality toassess for bony injury. However, in2005 Holmes suggested that onlyin patients with a depressed mentalstatus and high likelihood of cervi-cal spine injury should CT be theinitial mode of imaging. In popula-tions with less significant injuries anda lesser likelihood of cervical spineinjury, plain films still should be usedas the initial screening method.^"
In the past several years, there hasbeen a movement to make CT thestandard of care in the evaluationof the cervical spine in the traumapatient. The Eastern Association forthe Surgery of Trauma (EAST) hasstarted to recommend CT as thestandard way to evaluate the cervi-cal spine in those patients who donot meet NEXUS criteria and aresuspected of having a cervical spineinjury. In patients with neurologicdeficit, EAST recommends the addi-tion of an MRI in the evaluation of acervical spine injury.- '̂
In 2011 Duane et al studiedtrauma patients to evaluate theaccuracy of NEXUS criteria usingCT scan as the gold standard andfound NEXUS to miss a numberof significant injuries. They lookedat approximately 2600 patients andfound 26 with missed injury basedon die NEXUS criteria. Ofthe 26missed, 19 patients required addi-tional intervention in the treatmentof their injuries, including severalwho required operative repair andone who required placement of ahalo."
In symptomatic patients, ligamen-tous spinal injuries should also bea consideration. Once radiographsand/or CT have evaluated and arenegative for bony injury, flexion/extension films can be performed inthe awake patient to assess for sub-luxation, reflecting the presence ofligamentous injury. Three cervicalviews and a negative flexion/exten-sion film have been cited as havinga negative predictive value of 99%.^'In neurologically impaired individu-als, those who cannot flex or extendtheir neck secondary to pain or
muscle spasm, or those who cannotundergo flexion/extension films forany other reason but in whom a con-cern for cervical spine injury exists,flexion/extension films with fluoro-scopic guidance or MRI evaluationshould be performed.^*
MRI evaluation of patients iscostiy and time consuming. MRIshould not be performed in unstablepatients. In the evaluation oftheobtunded trauma patient, the cervi-cal spine can be cleared using MRI.The current data support the use ofMRI within 48 hours of the traumaevent to evaluate specifically for liga-mentous injury. Benzel et al studied174 patients with suspected cervi-cal spine injuries who underwentMRI evaluation. Thirty-six percentof patients were found to have MRIevidence of injury, but, more impor-tandy, none of the patients with anegative MRI had later spinal insta-bility and were ail cleared of theirimmobilization device.^^
Despite the evidence that sup-ports the use of plain radiographyin evaluation and clearance of thecervical spine, it is quite commonand acceptable for the emergencyphysician to order a CT in traumapatients, especially in the traumapatient who is going to requireother CT imaging. Simultaneousimaging ofthe cervical, thoracic,and/or lumbar spine is more effi-cient and reliable at assessing forinjury.^* It is also important toremember that any patient with asingle spinal injury is at risk for anadditional spinal injury, and thepresence of a single spinal injuryshould prompt radiographie evalu-ation of the remainder of the spinalcolumn. Plain radiographs (AP andlateral images of the thoracic andlumbar spine) are sufficient if thepatient is asymptomatic.
As with many conditions evaluatedby the emergency physician, follow-up within a reasonable period of timeis essential for the trauma patient.Patients with symptoms but nega-tive films and/or CT scan shouldcontinue the use of their rigid neckimmobilizer until neurosurgery canevaluate the patient.
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Surgical ConsultationIn the patient with spinal injury,
appropriate neurosurgical or ortho-pedic consultation is essential andshould be obtained in a timelymatter. Every hospital has specificguidelines as to which surgical ser-vices should be consulted based onthe level or severity of the injury orspecific deficits associated with theinjury. The goal of surgical inter-vention is spinal stabilization anddecompression of the spinal cordto prevent additional or ongoinginjury. Early decompression, if indi-cated, within 4-6 hours of injury mayimprove outcomes.
SteroidsThe use of high-dose steroids in
the presence of spinal injury usedto be the standard of care and wasincluded as part of many SCI guide-lines. In the past several years, thispractice has been called into questionand many studies have addressedthis controversy. Although currendycontroversy still exists surroundingthe use of steroids, the practice hasbeen removed from guidelines andis no longer considered the standardof care.
The purpose of steroids in spinalcord injury was originally thought tobe of benefit in three distinct ways.Steroids were thought to improveblood flow to the injured area ofthe spinal cord, assist in limiting theinflammatory response to injury, andreduce vasogenic shock and edema.
The National Acute Spinal CordInjury Study (NASCIS) I, II, andIII are the three largest prospec-tive, double-blinded, randomizedstudies on the use of steroids in spi-nal cord injury. NASCIS I studied330 patients with acute spinal cordinjury with two groups: a high-dosemethylprednisolone group against astandard-dose methylprednisoloneregimen. The patients were evaluatedat 6 weeks and 6 months followinginjury. NASCIS I found no differ-ence in outcome (recovery of sen-sory or motor function between thetwo groups, but although not statis-tically significant, both a higher rateof wound infection and early case
fatality were found in the high-dosemethylprednisolone group).^^
NASCIS II studied three treatmentgroups with a total of 487 patients:a high-dose methylprednisolonegroup (different dose than used inNASCIS I), a naloxone group, anda placebo group. In the high-dosemethylprednisolone group, statisti-cally significant improvements werefound with respect to pinprick andlight touch sensation at 6 weeksand 6 months following injury.Unfortunately, this finding was lostat one year post-injury. Post-hocanalysis revealed improved neuro-logic outcomes in groups receivingsteroids within 8 hours of their acuteinjury. Interestingly, patients receiv-ing steroids more than 8 hours fol-lowing injury were found to haveworse neurologic outcomes thanthe comparison groups, despite thisfinding not reaching statistical sig-nificance. Similarly to NASCIS I,there were more wound infections,pulmonary complications (includingan increase in pulmonary embolism),and adverse events noted in the ste-roid group.-^^
NASCIS III compared methyl-prednisolone given for 24 hours,methylprednisolone given for 48hours, and tirilazad mesylate givenfor 48 hours in patients with acutespinal cord injury. Patients wereassessed at 6 weeks and 6 months formotor frinction change, in additionto being scored on the FunctionalIndependence Measure (FIM). Thegroup receiving 48 hours of methyl-prednisolone and whose therapy wasstarted within 3-8 hours of injurywas found to have a statisticallysignificant improvement in motorscore at 6 weeks and 6 months (onefiill motor grade) and were morelikely to show improvement in theFIM scores. However, analysis ofthe groups reveals a disproportion-ate number of patients in the groupreceiving 48 hours of steroids whohad minor motor deficits on initialexamination as compared to theother two treatment groups. Thisdiscrepancy alone could account forthe statistical findings in the 48-hourtreatment group and, in fact, once
this discrepancy was controlled for,the statistical significance disap-peared. The group receiving tirilazadhad similar outcomes in motorrecovery rates to the treatmentgroup receiving methylprednisolonefor 24 hours. Like NASCIS I andII, there were higher complicationrates noted in the groups receivinghigh-dose steroids. The 48-hourtreatment group had higher ratesof pneumonia and severe sepsis ascompared to the 24-hour methyl-prednisolone and tirilazad groups.The conclusion drawn by the authorsof NASCIS III was that patients whoare started on a high-dose steroidregimen within 3 hours of injuryshould receive only a 24-hour courseof steroids, but those receivingsteroids within 3-8 hours of injuryshould be maintained on steroids for48 hours.2'
Ultimately, the use of steroids inacute SCI is controversial and shouidbe the decision of the institution andtreating physician. It is not currendyclear if there is a significant benefitin neurologic outcome with steroiduse, and more studies need to bedone, but it is clear that patients whoreceive steroids have higher compli-cation rates, including severe sepsis,pneumonia, pulmonary embolism,gastrointestinal bleeding, and woundinfections, than their counterparts.For these reasons, as mentionedabove, high-dose steroids are notcurrendy a part of treatment guide-lines for acute SCI. The Congressof Neurological Surgeons states thattreatment of acute SCI with steroids"should only be undertaken with theknowledge that the evidence sug-gesting harmfiil side effects is moreconsistent than any suggestion ofclinical benefit."^"
Blood PressureManagement
Blood pressure management inacute spinal cord injury is anotherarea in which class I evidence is lack-ing. It is clearly understood thathypotension can direcdy contrib-ute to hypoperfiision and result infrirther injury to the spinal cord.Many studies over the previous two
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decades have attempted to determinethe optimal blood pressure, or meanarterial pressure (MAP), in acute spi-nal cord injury and the duration oftreatment to maintain the proposedblood pressure. The theory is similarto that for steroids, in that the goalis to reduce secondary injury to thespinal cord from hypoperfiision.
It is well understood and acceptedthat, as with traumatic brain injury,autoregulation of blood flow to thespinal cord is compromised in acuteSCI. Animal models suggest thathypotension and, therefore, hypoper-ftision are detrimental in acute SCIand worsen neurologic outcomes.Because the treatment of hypoten-sion and shock is a basic tenet inmedicine, class I evidence supportingor refuting the use of a goal MAP inSCI will never be obtained.
In 1993 Levi et al studied hemo-dynamic parameters in acute cervi-cal SCI with 50 consecutive spinalcord-injured patients. The patientswere aggressively supported usingfluids and vasopressors to achievea goal systolic blood pressure ofgreater than 90 mm Hg. All patientsreceived invasive monitoring with anarterial Une, central venous access,and Swan-Ganz catheters. Datafor the first week following injury,including hemodynamic, neurologic,and demographic information, wereanalyzed. Ofthe 50 patients includedin the study, 31 had complete (gradeA) injuries, 20 had no improvementin function, 21 had appreciableimprovement, and 9 died."
Four years later. Vale et al stud-ied acute cervical and thoracicSCI in 70 patients. These patientsunderwent similar monitoring andhemodynamic augmentation strate-gies as in the Levi study and werefollowed to one year post-injury.The goal systolic blood pressure wasmaintained above 85 mm Hg for7 days following injury using fluidsand vasopressors. Patients in whomdecompression and spinal stabiliza-tion were indicated underwent thoseprocedures. The authors found thatafter one year, 60% of patients withcomplete injuries had improvementby one grade on the ASIA AIS, and
20% had return of bowel function.Thirty percent of these patients hadrecovered the ability to walk. Ofthose patients who sustained incom-plete cervical spine injuries, 92%recovered their ability to ambulateand 88% regained bladder control.Ofthe thoracic injuries, both com-plete and incomplete, improvementswere noted and, albeit smaller per-centages than their cervical coun-terparts, some demonstrated theability to walk and regained bladderfunction. A majority of patients withthoracic injuries underwent surgicaldecompression or stabifization of thespine. The authors controlled for thetiming of surgical intervention (earlyvs. late), and found no significantcorrelation between the timing ofsurgery and neurologic outcome.'^
In 2010, a literature review exam-ined the evidence supporting the useof vasopressors to augment bloodpressure in acute spinal cord injury.Unfortunately, the researchers wereunable to draw any definitive conclu-sions about the use of vasopressors,reporting that currentiy there is"no gold standard on vasopressorssupport." They did note, however,that cervical spine injuries requirevasopressor support much morefrequently than thoracic or lumbarinjuries." In both ofthe above men-tioned studies, minimal morbidityassociated with invasive monitor-ing and vasopressors administra-tion was observed. The authors ofboth studies recommend the use ofblood pressure augmenting medica-tions and fluids in the acute period(the first 7 days) following spinalcord injury. The authors thoughtthat the neurologic improvementsnoted in each study were the resultof improved perfusion and pre-vention of secondary injury fromhypotension.
The Congress of NeurologicalSurgeons states that there is "insuf-ficient evidence" to support treat-ment standards or guidelines, butdoes affirm that hypotension inacute SCI should be avoided and/or remedied as soon as possible. Alsorecommended is maintenance of aMAP between 85 and 90 for the first
7 days following acute injury to helpwith perfiision and prevent second-ary injury.'̂
Additional Issuesin Acute SCI
Once the patient has been stabi-lized and admitted to the hospitaland surgical consultations have beencompleted, there are several issuesthat patients face with new SCI, inaddition to the emotional and physi-cal adjustments of a new life.
Patients have significant autonomieinstability, often for several weeksfollowing their initial injury, whichrequires vasopressors and, frequentiy,long-term medications for stabiliza-tion. The general rule is, the higherthe injury, the more autonomieinstability can be seen and the longerthe duration of instability.
Early tracheostomy in patientswith cervical spine injuries has beenstudied and is becoming moreaccepted. Patients with cervical andthoracic spinal trauma often requireprolonged mechanical ventilationwhile hospitalized, and long-termmechanical ventilation is com-mon in patients with high cervicalspine injury.' In 2010 Romero et allooked at 152 consecutive patientswith acute spinal injury and dida retrospective study on the tim-ing of tracheostomy. Seventy-eightpercent of patients were grade Ainjuries. Early tracheostomy (pre-formed within 7 days of injury) wasshown to be beneficial for reducingthe number of days that mechanicalventilation was required, decreasingICU stays, and decreasing the riskof orotracheal complications fromintubation. The authors were notable to show a change in the risk ofmortality associated with injury ora reduction in the risk of ventilator-associated pneumonia.'* The tim-ing of tracheostomy has also beencontroversial due to concerns ofinfection following anterior spinalstabilization. Berney et al evaluatedearly tracheostomy after anteriorspinal stabilization and found thereis a low risk of infection, furthersupporting the idea that early tra-cheostomy is beneficial.'̂
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Secondary infection risks are sig-nificant in SCI patients. As statedabove, patients with spinal injuriesoften require prolonged mechanicalventilation and, therefore, have a sig-nificant risk of ventilator-associatedpneumonia. Urinary tract infec-tions are common among thesepatients, as well, given their needfor prolonged catheterization. Skinbreakdown and decubitus ulcers area common complication of immo-bility. Aggressive mobilization andphysical and occupational therapy areimperative in the prevention of ulcersas well as for the patient's generalrecovery.
Patients with SCI are at risk fordeep vein thrombosis (DVT) andpulmonary embolism (PE). Theincidence of DVT in the SCI popu-lation has been quoted between12-64%. Consequent PE results inapproximately 10% of deaths in thefirst year following SCI, despite theuse of chemical thromboprophy-laxis.^* Studies have been done toevaluate the effectiveness of inferiorvena cava (TVC) filter placement forprophylaxis. Whereas some stud-ies suggest the placement of IVCfilters for secondary prophylaxis inpatients with a PE or a contraindica-tion to chemical prophylaxis,'^ nostrong evidence exists to support theroutine placement, and some stud-ies suggest that IVC filter placementmay actually increase the risk of DVTdevelopment.^*
ConclusionAcute spinal cord injury is a com-
plex disease process that is oftencomplicated by additional traumaticinjury. Although physicians know asignificant amount about spinal cordinjury, there are many key areas stillto be fully understood. As a result,over the past decade, guidelineshave changed. The use of steroidsand vasopressors is controversial andrequires additional study. The emer-gency physician should be preparedto assess and treat the acute spinalcord injury regardless of level andshould be aware of the differencesin clinical presentation of injuriesat a specific level. The emergency
medicine physician is the criticalfirst step in the management of SCI,including airway management, imag-ing and clearance of the spinal cord,identification of other critical inju-ries, and initiation of pharmacologiemanagement that will minimize thelong-term morbidity and mortalityfor this devastating injury.
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