Term
Traumatic Brain Injury
• Epidemiology |
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Definition
• 2.5 million sustain TBI each year in the US either as an isolated
injury or along with other injuries
• Every day 150 people die from TBI
• 282,000 are hospitalized
• 2.5 million are treated and released from the ED
• Leading cause of death of people aged 1-44 years
• From 2001 to 2012, the rate of ED visits for sports and recreation- related injuries with a diagnosis of concussion or TBI more than doubled among children (age 19 or younger).
• Most effective means of fixing the problem – PREVENTION • Seat belts, airbags, helmets, restraints, safety seats, DUI/DWI |
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Term
| Causes of head trauma and traumatic brain injury (TBI) |
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Definition
• Falls (47%)
• Motor vehicle collision (MVC) (14%)
• Being struck by or against an object (15%)
• Intentional self-harm 2nd leading cause of TBI- related deaths |
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Term
| traumatic brain injury Pathophysiology |
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Definition
- Primary Injury
• Direct result of trauma
• Structural injury – fracture, hemorrhage, contusion
- Secondary Injury
• Cascade of molecular injury, inflammation, cytotoxicity • Disruption of blood-brain barrier
• Loss of autoregulation = Swelling, increased ICP
- Patients have already sustained primary injury on presentation
- Focus of management is to minimize secondary injury |
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Term
| Intracranial Pressure and tbi |
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Definition
ICP Hypothesis
• Skull holds a fixed volume
- 80% brain
- 10% CSF
- 10% blood
• Brain has limited ability to compensate for fluctuations in contents
Normal
• Normal ICP 2-20 mm Hg
• ICP 20-40 may result in secondary injury
- Blood vessel constriction - ischemia
• ICP >60 detrimental to neurons |
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Term
| Cerebral perfusion pressure (CPP) |
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Definition
= mean arterial pressure (MAP) – ICP
• Normal is 60-80 mm Hg
• Measure of how hard the heart is pumping against brain
pressure
• Cerebral blood flow is controlled via auto-regulation and dilating/constricting of vessels
• After trauma there is an initial decrease in cerebral blood flow followed by pathologic increase |
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Term
| Management of ICP and CPP |
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Definition
| been shown to improve survival and functional outcomes |
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Term
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Definition
• Severity dependent on amount of energy absorbed by
brain tissue
• Acceleration and Deceleration Injury
- Coup – site of impact
- Contracoup – opposite side of injury
• Rotation and shearing injury
- Diffuse tissue injury
- Vessel tearing->epidural, subdural hematoma |
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Term
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Definition
• Gunshot, screwdriver, ice pick
• Direct trauma from object
- Hematoma
- Bone fragments
- Foreign body
• Source of infection
• Injury dependent on velocity of object |
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Term
| traumatic brain injury initial assessment |
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Definition
• ABCDE
• Airway
• Breathing
• Circulation
• Disability – Neuro exam • Environment/Exposure
• Trauma survey – assess for other injuries |
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Term
| traumatic brain injury PE |
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Definition
• Lacerations, skull
depressions
• Basilar Skull fracture signs
- Battle’s sign, Raccoon’s eyes |
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Term
| traumatic brain injury neurologic assessment |
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Definition
• Mental status – alert, disoriented, lethargic, obtunded, comatose
• Glasgow Coma Scale
- 14-15 – mild TBI
- 9-13 – moderate TBI
- 3-8 – severe TBI
• If intubated, note “T” or “I”
• GCS < 8 considered comatose |
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Term
tbi Neurologic Assessment
• Cranial Nerves |
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Definition
• Common abnormalities and injury
• CN 1 Olfactory
• Basilar skull fracture, cribriform plate fracture
• CN 4 Trochlear
• Pain with eye movement, orbital fracture
• CN 7 Facial
• 10-50% injury with temporal bone fracture
• CN 8 Oculovestibular • Basilar skull fracture |
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Term
| • Cranial nerve indicators of increased intracranial pressure |
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Definition
• CN 2 Optic
• Papilledema - Optic disk swelling
• CN 3 Oculomotor
• Compressionpupil dilation
• CN 6 Abducens
• Runs against petrous bone, very susceptible to increase
in ICP
• Compression->limited adduction |
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Term
| tbi Indication for Head CT |
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Definition
- GCS 15 with:
• Headache, vomiting, age >60, EtOH or drugs, amnesia, visible trauma or skull fracture, seizure
- GCS<14–getaCT
• Focal deficit, amnesia, altered mental status
• Progressive headache, seizure, unreliable history, signs of injury |
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Term
Cervical Spine
• Consider unstable if: |
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Definition
• Significant trauma
• LOC, found down, event unwitnessed • Complaints related to neck or back
- Cervical collar and spinal precautions until cleared
• CT c-spine preferred modality
• Clear collar if CT is normal, patient is able to participate in exam and has no pain
• MRI for inconclusive CT, evaluate for ligamentous strain, comatose patient
- 5-15% of patient with skull fracture have c-spine fracture |
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Term
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Definition
• Simple - closed
• Compound – broken skin, open to contamination |
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Term
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Definition
• Fracture of bones of skull base - cribiform
plate, petrous bone, mastoid bone
• CSF leak in 11-45%
• High risk for CN injury
• Battle’s sign – retroauricular or mastoid ecchymosis
• Raccoon eyes – periorbital ecchymosis
• Hemotympanum – blood behind TM or in
ear canal |
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Term
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Definition
• Thinnest part of calvaium
• High risk for epidural hematoma with injury to middle meningeal artery |
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Term
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Definition
- 2-3% of head trauma patients
- Basilar skull fracture, temporal bone fracture
• Rhinorrhea – middle ear damage, CSF drainage to Eustachian tube and nasopharynx
• Otorrhea – perforated TM, drainage to external auditory canal
- Evaluation
• Fluid quality – clear fluid, salty taste,
“ring sign”
• Increased drainage with Valsalva or change in head position
• CT head – fractures, pneumocephalus |
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Term
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Definition
• Antibiotics – based on clinical scenario
• Bed rest, avoid straining
• Lumbar CSF drainage – divert fluid pressure away from the leak
• Surgical Repair |
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Term
Brain Injuries
• Concussion, mild TBI |
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Definition
• Axonal shearing forces->neuron
disruption and inflammatory cascade
• GCS 13-15 within 30 min of injury
• Signs/Symptoms
- Mild confusion, amnesia, +/- LOC at
event
- Headache, nausea, vomiting
• Standardized Assessment of Concussion (SAC), Sport Concussion Assessment Tool
• Post-concussive syndrome may last weeks to months
- Headache, dizziness, fatigue, insomnia, irritability, restlessness, difficulty concentrating, poor memory |
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Term
Brain Injury
• Return to Play |
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Definition
• Step 0 – complete physical and cognitive rest, no concussive
symptoms for 24 hours
• Step 1 – light low impact aerobic exercise, 5-10 min, no jogging, weight lifting, jumping
• Step 2 – moderate light impact exercise, reduced time than normal activity, jogging, light weight lifting
• Step 3 – non-contact exercise, normal time of exercise, regular weight lifting, non-contact sports drills
• Step 4 – Practice
• Step 5 – Return to competition
• Return to health care provider if symptoms increase or change |
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Term
Brain Injuries
• Contusion |
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Definition
• Focal parenchymal hemorrhages that result from the brain scraping and bruising against skull
• Frontal and temporal areas most common
• Coup/Contre-coup
• Delayed hemorrhage,
“blossoming”
• Complications – seizures, edema, hemorrhage |
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Term
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Definition
| Post-traumatic CT scan of brain showing bilateral contusion of frontal cerebral region |
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Term
Brain Injuries
• Diffuse Axonal Injury (DAI) |
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Definition
• Rotation or deceleration causes microscopic
and macroscopic axonal shearing
• Gray-white junction, corpus collosum, midbrain
• Autonomic dysfunction causes “storming”
- Hypertension, hyperhydrosis, hyperpyrexia
[image] |
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Term
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Definition
• 1% of head trauma admissions, 20-55% mortality
• Collection of blood accumulates between the skull and
dura, caused by arterial injury
• 75-95% associated with skull fracture – temporal bone and middle meningeal artery most common
• Triphasic presentation
- Transient LOC
- “Lucid Interval”
- Rapid neurologic deterioration – obtunded, dilated pupil, hemiplegia |
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Term
| Epidural Hematoma imaging |
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Definition
| • CT scan – high density biconvex (lens) shape along skull |
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Term
| epidural hematoma treatment |
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Definition
• Medical vs. surgical based on patient condition and hemorrhage size
• Serial imaging |
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Term
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Definition
• Collection of blood between the dura and brain
• Venous injury – cortical vein crossing from cortex and
dural sinuses
• Risk factors
- Elderly
- anticoagulation
- Alcohol
• Presentation variable – growing hemorrhage puts pressure on cortex
- Headache, focal deficits, progressive symptoms |
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Term
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Definition
• CT scan – crescent shaped hemorrhage along hemisphere
• Multiple ages of blood may be present
• Treatment – surgical vs. medical depending on symptoms and risk factors
- Burr holes vs. craniotomy |
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Term
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Definition
• Spontaneous arterial bleeding into subarachnoid space
• May result from an aneurysm
- Associated with connective
tissue disease
- Head trauma as a cause is
rare
• Abrupt onset
- Worsens over 30–90 min
• Causes headache, stiff neck,
photophobia, and papilledema
• Blood in spinal tap
• Treatment
- Nimodipine reduces risk of stroke
- Surgical clipping |
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Term
Increased Intracranial Pressure
• ICP Monitoring |
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Definition
- Indications
• Severe head injury (GCS 3-8)
• Closed head injury with known hematoma, edema, contusion
• Poor exam or systemic injury not amenable to following exam-• Contraindications
• Coagulopathy
• Poor prognosis not expected to survive ICU course |
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Term
Intracranial Pressure
• ICP Monitoring methods |
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Definition
- Ventriculostomy
• Gold standard
• Catheter inserted into 3rd ventricle
• Allows for therapeutic CSF drainage
• Risks – infection, hematoma, stroke
- Fiberoptic transducer
• “bolt”
• Subdural, intraparenchymal, or epidural
• Lower cost and risk
• Loss of accuracy |
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Term
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Definition
• Goal Cerebral perfusion pressure >60, ICP <20
• Elevate head of bed
• Hyperventilation – pCO2 28-32 (normal 35-45)
- Low pCO2 causes vasoconstriction
- Decreased blood = more room
- Avoid 24-48 hours post-injury
• Sedation, decrease stimulation
- Agitated patient, discomfort on ventilator
- Propofol, Fentanyl
• CSF removal
- Ventriculostomy – drain open at variable level to allow for CSF drainage
- Osmotic agents
• Mannitol – osmotic diuretic
• Hypertonic saline
- Surgery
• Decompressive hemicraniectomy
• Evacuate mass/hematoma
• Lobectomy |
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Term
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Definition
• Mass effect causes shift of brain from one compartment into another
• Cause altered LOC due to mass effect, compression on brain stem and reticular activating system |
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Term
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Definition
- Seizures – can increase ICP
• Most commonly within 24 hours of injury • Prophylaxis 7-10 days
- Infection
• Wound, pneumonia, urinary
- Vascular injury
• Horner’s syndrome – disruption of sympathetic fibers
that track with carotid artery • Ipsilateral miosis, ptosis, +/- anhidrosis • Raises concern for ICA dissection
• Traumatic pseudo-aneurysm |
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