HEAD TRAUMA August, 22, 2002 Adam Oster PGY2 Dr. Mark Yarema
HEAD TRAUMA Outline • Epidemiology • Biomechanics of HI • Minor HI • Canadian CT Head Rule • future developments • Severe HI • physiology • management issues and controversies • future developments • Pediatric HI
HEAD TRAUMA • Epidemiology • approx 1 000 000 HI evaluated in ED in N.A/yr • majority (80%) are minor or minimal • majority of these can be discharged home safely • small percentage will deteriorate and require neurosurgery • early diagnosis of these NSx lesions is important and effects long short and long term outcome • 50 000 die before reaching the ED • leading cause of traumatic death in males <25 y.o
Primary Direct Injury occurs at the moment of the injury damage can occur directly beneath the area involved; #, EDH, ICH, contusion or occur remotely from propagation of energy Indirect Injury occurs when the cranial contents are set in motion within the skull SDH, DAI, coup-contra-coup pattern, concussion. HEAD TRUMA:BIOMECHANICS
Secondary Injury Hypoxia includes seizures Hypotension Decreased CPP (CPP=MAP-ICP) Anemia Systemic and Metabolic insults Infection areas of brain suffering irreversible primary injury are surrounded by a penumbra of tissue that is injured but potentially salvageable. HEAD TRUMA:BIOMECHANICS
HEAD INJURY CLASSIFICATION • MINOR (80%) • GCS 13-15 • MODERATE (10%) • GCS 9-13 • SEVERE (10%) • GCS 3-8
30 yo woman fell from a ladder 45 minutes ago while painting her house, witnessed by her husband. No LOC. Previously healthy. • What else do you want to know? • O/E • eyes are open • converses but not sure why she’s in the hospital • obeys commands • no focal deficits • GCS -- • remainder of exam normal
Minor HI • CT scan? • What is her risk of a NSx lesion • A “clinically important” brain injury • death from this HI
GCS 13-15 amnesia, disorientation and confusion are common no focal neurologic deficits Controversy about including GCS 13 in minor HI since the rates of NSx lesions and sequelae are closer to moderate HI (GCS9-12) than minor (GCS 14-15( 3% will deteriorate 1% have surgical lesions <0.5% will die Minor HI
CT scan in Minor HI • An ongoing and evolving issue • scan everyone • scan no one • selective scanning • wide variation in inter-physician and teaching hospital scanning rates
History of the debate • Haydel, 2000 • H/A • Vomiting • Age>60 • Drug or ETOH intoxication • Amnesia • Seizure • Trauma above the clavicles • Sens 100% (95%-100%) for CT abnormality • Sens. for NSx intervention 54%-100% (N=6)
Rosen 2002: High Risk Focal neurologic findings Asymmetric pupils Skull fracture Multiple trauma Serious, painful, distracting injuries External signs of trauma Initial Glasgow Coma Scale score of 13 Loss of consciousness (>2 min) Posttraumatic confusion/amnesia (>20 min) Progressively worsening headache Vomiting Posttraumatic seizure History of bleeding disorder/anticoagulation Recent ingestion of intoxicants Unreliable/unknown history of injury Suspected child abuse Age >60 yr, <2 yr
Rosen 2002: Low Risk Currently asymptomatic No other injuries No focality on examination Normal pupils No change in consciousness Intact orientation/memory Initial Glasgow Coma Scale score of 14 or 15 Accurate history Trivial mechanism Injury >24 hr ago Reliable home observers
LOC incidence of IC lesions range 1.3% to 17.2% GCS 15 and LOC 6.1% to 9.4% IC lesion incidence rises with increasing with LOC duration <5mins 5.9% >5mins 8.5% H/A, nausea and vomiting about 2x as likely to occur in HI without IC lesion as in HI with IC lesion. Seizure no correlation with IC lesion incidence Signs and Symptoms:Correlation with IC Lesion Emergency Medicine Clinics Of North America vol 17, no.1. Feb., 1999.
GCS 15 Shackford et. al IC lesion rate 14.8% 3.2% required crani. GCS 15 Miller et. al. IC lesion in 6.1% 0.2% required NSx. Anisocoria incidence of IC increased with extent. >1mm, 30% IC lesion >3mm, 43% Basal Skull # 53%-90% IC lesion Signs and Symptoms:Correlation with IC Lesion Emergency Medicine Clinics Of North America vol 17, no.1. Feb., 1999.
Canadian CT Head Rule • 3121 patients multicentred, prospective cohort study • inclusion criteria • GCS 13-15 • witnessed LOC, amnesia or disorientation • injured within the past 24hrs • Excluded; <16, no LOC/amnesia/disorientation, obvious depressed skull #, penetrating skull inj., focal neuro deficit, Sz post-injury, pregnant, congenital or acquired bleeding disorder.
Primary outcome need for neurosurgical intervention intubation or death within 7d, craniotomy, elevation of skull#, ICP monitoring. Secondary outcomes Clinically Important Brain Injury “an injury which would normally require admission and neuro follow-up” consensus of EPs, neurosurgeons and neuroradiologists CIBI Solitary contusion <5mm Localized SAH SDH<4mm Isolated pneumocephaly Closed and depressed skull#, not through inner table Canadian CT Head Rule
Canadian CT Head Rule • Study Design • Patients assessed for 22 standardized findings on Hx, PE and neurological exam. • CT scan at discretion of physician • Follow-up by phone at 14days for those who did not have a CT to determine the presence of CIBI.
Canadian CT Head Rule • Results • 1% (44) required neurosurgical intervention • 0.13% (4) died • 8% (254) CIBI • 4% (94) CUIBI • small SAH, contusions <5mm • 67% had CT, 33% phone follow-up, 363 (%) lost to follow-up
Canadian CT Head Rule • 7 variables with good IO agreement and strong association with the outcome • Goal was highest sensitivity while still achieving greatest specificity • Stratifies patients into three groups • high risk for the primary outcomes measure or • medium risk for the secondary outcome • Low risk for either outcome
Canadian CT Head Rule • High risk (for neurological intervention) • GCS score <15 at 2 hours after injury • Suspected open or depressed skull fracture • Any sign of basal skull fracture • hemotympanum, "raccoon" eyes, CSF otorrhea or rhinorrhea, Battle's sign) • Vomiting > 2 episodes • Age > 65 years • Sens 100% (92%-100%) • Spec. (67%-70%)
Canadian CT Head Rule • Medium risk (for brain injury on CT) • Amnesia before impact >30 minutes • Dangerous mechanism • pedestrian struck by motor vehicle, occupant ejected from motor vehicle, fall from height >3 feet or 5 stairs • Sens. 98.4% (96%-99%) • Spec. 49.6% (48%-51%)
Canadian CT Head Rule • Questions • Is the sensitivity high enough? • Will it reduce the frequency of scanning Mild HI patients
35 y.o intoxicated male brought in by EMS. Witnessed fall from own height at an LRT station approx. 45 minutes ago. • Open eyes to shouting, sleeping but easily roused with pain, swearing, moves all 4 limbs vigorously. VSS. • Obvious scalp lacerations. Remainder of exam normal. • Image now or observe?
Same guy but you’ve been busy. Now injury was approx. 6hrs ago. • Opens eyes to shouting, swears, moves all four limbs spontaneously. • Now what?
50 y.o woman with chronic a.fib.. Husband saw her fall from the first rung of a step ladder. She cannot remember what happened. Otherwise healthy. • GCS 15. • Disposition?
16 yo boy fell while skateboarding. LOC approx 10 secs. Now feels fine. • GCS 15, normal exam. • Disposition?
Concussion • “A brief alteration in mental function after minor head trauma.” (Rosen, 2002). • Absent cerebral autoregulation for days following • Advice on discharge? • Depends on extent of concussion
Concussion • Grade 1 = confusion without amnesia, no LOC • Grade 2 = confusion with amnesia, no LOC • Grade 3 = LOC
Concussion: Grade 1 • Remove from sporting event immediately. Examine immediately and serially for development of amnesia and post-concussive symptoms at rest and with exertion. • Consider return to sport if amnesia does not appear and no symptoms appear for at least 20
Concussion: Grade 2 • Remove from event. Re-examine next day. • May return to practice only after 1 full week without symptoms.
Concussion: Grade 3 • Transport to hospital for evaluation. Admit and observe if concerns of clinically significant brain injury. If no concern, discharge with instructions to family for overnight observation. • May return to practice only after 2 full weeks without symptoms
30 yo helmeted male mountain biking in Edworthy. Came off bike while travelling downhill. Struck side of head on tree. Brief LOC. Immediate neck pain. Friends helped him up and they walked him out to their car. Drove him to the ED.
GCS 15, PERL 3mm • No focal neurologic deficits. • Central c-spine tenderness. • Rest of exam wnl.
HI and Pediatrics • Important to separate the traumatic or accidental from the non-accidental. • Adult resuscitation principles apply, e.g avoiding hypoxia, hypotension, hyperthermia. • Challenge is predicting who is low risk enough to be observed and discharged home.
Pediatric HI:General Principles • The younger the child the lower your threshold should be for imaging • The greater the forces the lower your threshold should be • The more physical symptoms the lower your threshold should be • Consider intentional injury/neglect. • Can get hypovolemic hypotension
Pediatric HI: Predictors for Intracerebral Injury Trauma Reports, 2000. • Skull # • better predictor than clinical symptoms • Sens. 60% to 100% • Scalp hematoma (sens 80% to 100%) and young age are predictors for SF • Altered mental status • Focal neurological findings • Scalp swelling, • HI without a clear history of trauma • In the <6mo. May be asymptomatic • LOC and vomiting are not predictive.
High Risk Decreased LOC Focal findings Basal or any skull # Irritability bulging fontanelle *LOC>1min, post-injury SZ, worsening vomiting *Consensus guideline Low Risk Trivial (low energy) mechanism Fall <3feet No signs/symptoms at >2yrs post-injury Age >3mo Require a period of observation for deterioration. Pediatric HI:Risk Stratification < 2 y.o Pediatrics. Vol 17, no. 5. May, 2001
Pediatric HI: Normal CT and Discharge • 3 studies • HI and Normal CT • Incidence of deterioration was 0 • (95% CI 0-1.4%)
No LOC and Normal Exam observe for up to 24hrs by a competent adult LOC and normal exam may consider observation by competent adult CT if high risk mechanism or currently symptomatic (e.g vomiting, seizure…) Rosen, 2002: Pediatric minor HI and Management
26 yo male, brought in by STARS from Canmore for CHI. • EMS on scene -- GCS 11, full spines • STARS called for transport to FMC • In ED • 90, 120/70, 16, 99% on 5L by np, 36.5 • opens eyes to shouting his name, moaning, 4 limb spontaneous movement.
Key Historic Info MVC fall height, landing position, assault weapon LOC amnesia Sz (Hx of Sz) vitals and GCS on scene and transport AMPLE current complaints 26 yo previously healthy male. Unrestrained passenger in high-speed single vehicle rollover. No airbags. ?LOC No alcohol/drugs involved Head Injury:History
Key Clinical Info ABCs --high incidence of polytrauma GCS Head and neck ?basal skull# pupils size, reactivity, asymmetry motor exam symmetry, abnormal posturing, strength. Cranial nerves gag, corneal ref. DTRs and pathologic reflexes vitals ?herniation syndromes Approx 60% TBI will have a second system injury 16% associated c-spine injury Head Injury: Physical Exam
Head Injury:Glasgow Coma Scale • *GCS • developed for assessment at 6hrs post-injury • isolated HI and hemodynamically stable • use at <6hrs is limited • hemodynamics, intubation, ETOH, sedation/paralysis • does not assess brainstem function
SEVERE HI • Prevention of secondary injury • 1 episode of hypotension (SBP<90) increased mortality by 150%. • Hypoxia (paO2<60) also significantly increased mortality (but less than hypotension). • Combined hypotension and hypoxia more detrimental than either alone. Chestnut, RA. Analysis of the role of Secondary Brain Injury in determining the outcome from severe head injury. J. Neurosurg 1990;72:360.
26 yo male, brought in by STARS from Canmore for CHI. EMS on scene -- GCS 11, full spines STARS called for transport to FMC In ED 90, 120/70, 16, 99% on 5L by np, 36.5 opens eyes to shouting his name, moaning, 4 limb spontaneous movement. GCS 12 (E3, V3, M6) Hemodynamically stable no focal complaints Management Airway and Breathing BP imaging CT head nil acute c-spine films normal Disposition...