Brain Injury 8_08_12 MB

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TRAUMATIC BRAIN
INJURY IN CHILDREN
Marc D. Berg, M.D.
Professor of Pediatrics
Chief, Pediatric Critical Care Medicine
Medical Director, University of Arizona Physicians
0
OBJECTIVES
Review Of…
 Physiology, Assessment, and
Management of TBI
 Outcome in Children With TBI
 Correct Common Myths
CHILDHOOD HEAD INJURIES:
STATISTICS
• 85% are “mild”, but…
• 80% of children with multiple trauma
die because of severe head injury
(50% in adults)
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–
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> Head/body ratio
Softer skull
Open fontanelles
MYTH #1
• Myth…All Brain Injuries Are the Same
• Fact… Each Brain Injury Is Different
DEFINING SEVERITY
• Mild Brain Injury
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–
–
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GCS = 13-15
Limited impaired consciousness (<30 min)
Normal CT scan
Shows signs of a concussion
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•
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Vomiting
Lethargy
Dizziness
Lacks recall about injury (<1 hr PTA)
DEFINING SEVERITY
• Moderate Brain Injury
–
–
–
–
GCS = 9 - 12
Impaired Consciousness (<24)
CT scan Evidence
PTA 1-24 hr
• Severe Brain Injury
– GCS = 3 - 8
– Impaired Consciousness (> 24 hours)
– PTA > 24hr
CAUTION!!
• GCS of 13 may not be so “mild”
• SC Stein, J Trauma. 2001;50:759-760
– Reviewed 14 studies (1047 adult patients with GCS of 13)
– 33.8% had intracranial lesions
– 10.8% required surgery
MYTH #2
• Myth… Younger children recover better
than older children.
• Fact… The developing brain may be at
more risk. It will take longer to see the
effects of the brain injury.
INTRACRANIAL
FLUID COMPARTMENTS
(INTRACELLULAR AND
EXTRACELLULAR)
MODIFIED MONROE-KELLIE DOCTRINE
For pressure to remain constant, an increase in
volume in one compartment must be accompanied
by an equal decrease in the volume in others
C
ICP
B
A
VOLUME
CEREBRAL BLOOD FLOW/
AUTO REGULATION
• May be lost after
trauma
• Principles are used in
treatment strategies
but are the source of
much debate
From Shapiro HM: Anesthesiology 43:445-471, 1975
CEREBRAL PERFUSION PRESSURE
• CPP = MAP - ICP
• Useful Concept, But Has Limitations
• Good CPP, Better Outcome In Adult Literature (>70
mmHg in adults, >40-65 mmHg ? in children)
• The CPP (>70) versus the ICP(<20) As The Primary
Therapeutic End-point (Debatable Concept)
BRAIN INJURY
PATHOPHYSIOLOGY
• Primary Brain Injury (occurs at time of impact)
–
–
–
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Intracranial hemorrhage
Diffuse axonal injury
Hyperemia/edema
Ischemia, release of toxic mediators
SUBDURAL VS. EPIDURAL
LifeArt: Williams & Wilkins
http://www.lifeart.com
SUBDURAL HEMATOMA
WebPath: University of Utah
http://www-medlib.med.utah.edu
EPIDURAL HEMATOMA
SUBDURAL VS EPIDURAL HEMATOMA
• EPIDURAL
– Requires linear
force
– Associated with
skull fracture and
torn artery. Brain
often uninjured
– “Lucid” interval
common
– Common in
accidental trauma
• SUBDURAL
– Requires significant
rotational forces
– Associated with brain
injury and torn bridging
veins
– Neurologic symptoms
from the start
– Common in infants
with abusive head
trauma
PEDIATRIC FALLS FROM HEIGHTS
• Falls From 1 - 3 Stories Often Not Fatal
• Falls Less Than 4 Feet Often Reported in Fatal Injuries
– Unwitnessed
– Subdurals
– Retinal Hemorrhages
• Falling off a Bed or Couch Should Not Kill!
COUP - CONTRA COUP INJURY
BRAIN INJURY
PATHOPHYSIOLOGY
• Secondary Brain Injury :
– Occurs over hours to days (hypoxia, hypercarbia,
hypotension/ischemia, intracranial hypertension,
acidosis, seizures, hyperthermia, hypothermia,
infections
– Potentially Avoidable Or Treatable With Close
Monitoring / Treatment of ABC’s
UNCONTROLLED INTRACRANIAL
PRESSURE AND/OR CEREBRAL
PERFUSION
DISPLACEMENT OF
NERVOUS TISSUES
DECREASED GLOBAL
AND REGIONAL
OXYGEN DELIVERY
HERNIATION
DEATH
WORSE FUNCTIONAL
OUTCOME
KEY POINTS
• THE BRAIN NEEDS OXYGEN
• OXYGEN IS CARRIED IN BLOOD
NO BLOOD, NO OXYGEN, …
…BRAIN CELLS DIE
ASSESSMENT
MINOR CLOSED HEAD INJURY
• Evaluation and Management of Children Younger Than
Two years old With Apparently Minor Head Trauma:
Proposed Guidelines
– Schutzman SA et al., Pediatrics 2001; 107:983-993
• The Management of Minor Closed Head Injury in
Children
– AAP/AAFP, Pediatrics 1999; 104:1407-1415
IMPORTANT ISSUES FOR THE < 2 YEAR OLDS
•
•
•
•
•
Clinical Assessment Difficult!
Occult ICI More Common
Increased Risk of NAT
Increased Risk of Skull Fracture
Increase Sedation Risk
MYTH #3
• Myth… A mild brain injury has no consequences.
• Fact… A mild brain injury can affect a child’s
ability to concentrate, learn and function at home
and in school.
CASE PRESENTATION
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6 year old male
Struck by car while riding his bike
Brought in by EMS with c-spine protected
Spontaneously breathing
GCS = 8
HR = 145, RR = 25, B/P = 80/45, O2 sats = 99%
Multiple abrasions, no other obvious injuries
Next Steps?
INITIAL ASSESSMENT
• A IRWAY
• B REATHING
• C T SCAN
CIRCULATION
MANAGEMENT OF TBI
INITIAL MANAGEMENT
• Level II and III (adult and pediatric):
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–
–
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AVOID HYPOTENSION AND HYPOXIA
Know Age Based Normals (For children keep BP > 5th %tile)
In adults, MBP > 90.
Intubate if GCS < 9 (peds) and Airway or Oxygenation is Unstable
(adults)
EARLY RESUSCITATION OF CHILDREN WITH
MODERATE-TO-SEVERE TRAUMATIC BRAIN INJURY
PEDIATRICS 2009;124;56-64 MICHELLE ZEBRACK, CHRISTOPHER DANDOY,
KRISTINE HANSEN, ERIC SCAIFE, N. CLAY MANN AND SUSAN L. BRATTON
• CONCLUSIONS: Hypotension and hypoxia are common
events in pediatric traumatic brain injury. Approximately
one third of children are not properly monitored in the early
phases of their management. Attempts to treat
hypotension and hypoxia significantly improved outcomes.
EMERGENCY MANAGEMENT
AIRWAY
•
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Handle Neck With Caution: Assume C-spine Injury
Use Jaw Thrust
Avoid Obstruction of Venous Drainage
Intubate If GCS < 8
May Need to Protect Airway Due to Seizures or Trauma
Intubation Should Be Oral
atlas
odontoid
EMERGENCY MANAGEMENT
BREATHING
• Even a Small Rise in PaCO2 Causes a Significant Rise in
ICP
• “Adequate” Breathing May Not Be Enough- Aim for
PaCO2 of 35-40 Torr
• Hyperventilation Is the Quickest Way to Lower ICP If
There Are Signs of Herniation
EMERGENCY MANAGEMENT
CIRCULATION
• Blood Pressure Must Be Optimized to Help Maintain
Adequate CPP
• Only Use Isotonic Fluids for Volume Expansion
• May Need Inotropic or Pressor Support
• Control Bleeding
EMERGENCY MANAGEMENT DISABILITY
• Glasgow Coma Score
– Modified for Children
• Cranial Nerve Exam
– Including Pupillary Response to Light, Eye Position and
Movement, Corneal Sensation, Gag
• Motor, Sensory, Reflex Exam
• Cranial Exam
– Evaluate for Fractures, CSF Leak, Battle’s Sign Etc.
GLASGOW COMA SCALE
• BEST MOTOR
RESPONSE (1-6)
• EYE OPENING (1-4)
1-none
1-none
2-abnormal extension
2-response to pain
3-abnormal flexion
3-response to voice
4-withdrawal from pain
4-spontaneous
5-localization of pain
6-obeys commands
• BEST VERBAL RESPONSE (1-5)
1-none
2-incomprehensible
3-inappropriate
4-confused
5-oriented
GLASGOW COMA SCALE
(MODIFIED FOR YOUNG CHILDREN)
• BEST VERBAL RESPONSE (1-5)
•
1-none
•
2-restless, agitated
•
3-persistently irritable
•
4-consolable crying
•
5-appropriate words, smiles, fixes/follows
MANAGEMENT OF TBI
• Guidelines For The Management of Severe (Adult) Head
Injury
– A joint venture of
• The Brain Trauma Foundation
• The American Association of Neurological Surgeons
• The Joint Section on Neurotrauma and Critical Care
– Journal of Neurotrauma, 1996; 13:626-734
– Journal of Neurotrauma, 2000; 17:451-553
– Journal of Neurotrauma, 2007; 24:s1-s106
GUIDELINES FOR THE ACUTE MEDICAL
MANAGEMENT OF SEVERE TRAUMATIC BRAIN
INJURY IN INFANTS, CHILDREN AND ADOLESCENTS
• Crit Care Med 2003 Vol. 31, No. 6 (Suppl.)
• Endorsed or supported by:
– American Association for the surgery of Trauma
– Child Neurology Society
– International Society for Pediatric Neurosurgery
– International Trauma and Critical Care Society
– Society of Critical Care Medicine
– World Federation of Pediatric Intensive and Critical Care Society
– National Center for Medical Rehabilitation Research
– National Institute of Child Health and Human Development
– Syntheses USA
– The International Brain Injury Association
DEVELOPMENT OF GUIDELINES
• CLASSIFICATION OF
EVIDENCE
– CLASS I (PRCT)
– CLASS II (“clearly
reliable data”)
– CLASS III (retrospective,
case reviews, clinical
series)
– TECHNOLOGY
ASSESSMENT
• DEGREES OF
CERTAINTY
– STANDARDS (high
degree)
– GUIDELINES (moderate
degree)
– OPTIONS (unclear)
CASE CONTINUES…
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Pt intubated, on vent
20/Kg Saline given
B/P 115/75, HR 120, O2 sat 100%
GCS = 7 (Paralyses from RSI resolved)
Head CT = small scattered contusions, small non-surgical
sub-dural.
• Abd CT = neg
• C-spine CT = neg
What next?
MANAGEMENT OF TBI
INDICATIONS FOR ICP MONITOR
• OPTION (Pediatric):
– Severe head injury (GCS ≤ 8)
CASE CONTINUES…
•
•
•
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Pt has ventriculostomy placed
Clear CSF flows freely
ICP = 26mmHg
MAP = 70, HR = 100, RR = 15 (on vent), O2sat=99%,
GCS = 7, PEERL
• Questions? Plans?
MANAGEMENT OF TBI
HYPERVENTILATION (PEDIATRIC)
• OPTIONS (no standards or guidelines):
– Mild or prophylactic hyperventilation (pCO2 < 35 mmHg) should
be avoided.
– Mild hyperventilation (30 - 35 mmHg) may be considered for
longer periods if ICP refractory to all other tx.
– Aggressive hyperventilation (< 30mm Hg) considered second tier
for refractory hypertension.
CASE CONTINUES…
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ABG shows pCO2 of 45
Vent rate increased to 18/min, 20/kg NS IV bolus
Repeat pCO2 = 35
ICP still 25, MAP = 75, CPP = 50
Head of the bed elevated to 30o
Pt is sedated and paralyzed
No change in ICP or CPP
What next?
MANAGEMENT OF TBI
OSMOTHERAPY - PEDIATRIC
• STANDARDS: none
• GUIDELINES: none
• OPTIONS: HT Saline is effective for control of raised ICP
(.1-1 ml/kg/hr). Mannitol is effective therapy (0.25-1/kg)
for control of raised ICP
– Keep osmolarity <320 (maybe higher for HT saline)
– EUVOLEMIA MUST BE MAINTAINED!
CASE CONTINUES…
• Pt started on Hypertonic saline
• Repeat CT shows diffuse swelling and evolution of
contusions.
• ICP now 34, MAP = 70, CPP = 46, PER slugish
• HR = 82
• GCS = 5 when not paralyzed
What now? Time to quit? Is there a chance for good
outcome?
OUTCOME IN PEDIATRIC HEAD INJURY
LIMITATIONS OF THE GLASGOW COMA SCALE IN PREDICTING
OUTCOME IN CHILDREN WITH TRAUMATIC BRAIN INJURY LIEH-LAI MW,
THEODOROU AA, ET AL. J PEDIATR 1992;120:195-9
• 64% with GCS≤5 survived
• Nonsurvivors had greater incidence of shock/CPR
• 45 survivors with GCS3-11 had neuropsychologic testing
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37% memory deficits
30% speech/language deficits
34% motor function deficits
18%attention deficits with or without hyperactivity
CASE CONTINUES…
• ICP now 34, MAP = 70, CPP = 46, PER sluggish
• HR = 82
• GCS = 5 when not paralyzed
• Dopamine started, pCO2 now 30, HR = 72, pupils
becoming asymmetric…
MANAGEMENT OF TBI
BARBITURATES
• “Option”(Level II for adults): may be considered if ICP
control is refractory to other treatment and patient is
hemodynamically stable
– Reduction in cerebral O2 requirement, ICP
– Pentobarbital 2-4 mg/kg/dose, 1-2mg/kg/hour, burst-suppression
on EEG
– Questionable effect on outcome
– Disadvantages:
myocardial function - use inotropes. Difficult
neuro exam
MANAGEMENT
CRANIAL DECOMPRESSION
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•
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Ventriculostomy (“option”)
Tumor Debulking
Hematoma Evacuation
Lobectomy
Decompressive Craniectomy (“2nd tier”)
MANAGEMENT OF TBI
STEROIDS
• STANDARDS: NOT recommended for improving
outcome or reducing ICP in TBI
• Useful for edema around brain tumors
– Dexamethasone 0.4mg/kg/q 6 hours
MANAGEMENT OF TBI
SUPPORTIVE MANAGEMENT
• Temperature control - Maintain low normal temp. ~35˚c
(hypothermia under study)
• Head position - 15-30 elevated, avoid jugular
compression
• Pain control- pain is bad on ICP!!!
• Seizure control (prophylaxis is “option”)
• Antibiotics
• Adequate nutrition (VERY IMPORTANT!!)
CRITICAL PATHWAY FOR INCREASED ICP TREATMENT
CRITICAL PATHWAY FOR INCREASED ICP TREATMENT
CRITICAL PATHWAY FOR INCREASED ICP TREATMENT
CASE PROGRESSION…
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ICP normalizes after 2 weeks
GCS 8-9
Pt has trach and G-tube
Transferred to inpatient rehab after 1 mos
Returns to PICU to say “Hi” one year later…
MYTH #4
• Myth… A Severe Brain Injury Means that the Child Will
Be Permanently and Totally Disabled.
• Fact… Patterns of Recovery Vary.
– ~80% will have some type difficulty.
– The long term consequences are different for each child.
OUTCOME IN PEDIATRIC
HEAD INJURY
• Better Then You Think, (For Severe Injury) So Be
Aggressive!
• Do NOT Rely on Initial GCS For Prognosis
• Mild Brain Injury May Have More Consequences Than
Expected
• Injury Severity and Level of Family Support May Best
Predict Outcome!
MYTH # 5
• Myth… The brain injury can’t be that serious if the child
came right home from the hospital.
• Fact… More children with disabilities go home upon
discharge from the hospital than to in-patient rehab.
THANK YOU
marcb@peds.arizona.edu
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