Craniocerebral Trauma: Junchen Zhang

Craniocerebral Trauma Junchen zhang

Purpose ●

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To understand the pathogenesis ['pæθə'dʒenɪsɪs] ,pathobiology [pæθəbai'ɔlədʒi] To master clinical features,medical treatment,surgical treatment of head trauma. Time: 3 hours

Craniocerebral Trauma ●

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is the leading cause of death among persons under 45years of age 4 million head injuries in US per year can involve injury to the scalp,skull,meninges [mi'nindʒi:z] ,or brain.

Anatomy Review

Craniocerebral trauma can involve injuey to the Scalp, skull, meninges, brain.

Skull Anatomy Review ●

Basilar skull Anterior fossa Medial fossa(Middle meningeal arterylies under temporal bone,common source of epidural hematoma) posterior fossa ■

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Brain Anatomy Review ● ●

Occupies 80% of intracranial space Divisions ■

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Cerebrum Cerebellum Brain Stem

顶叶

中央沟

额叶

枕叶

外侧裂 颞叶

Mechanisms of Injury

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Motor Vehicle Crashes ■

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Sports Injuries Falls ■

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most common cause of head trauma most common cause of subdural hematoma

common in elderly and in presence of alcohol associated with subdural hematomas

Penetrating Trauma ■

missiles more common than sharp projectiles

1. Acceleration-deceleration injury

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typically seen following high-speed motor vehicle accident brain (neurons,axons )and blood vessels being particully vulnerable. most common cause of head trauma most common cause of subdural hematoma , diffuse axonal injury ,subcortical hematoma,

2 impact injury

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is often seen following assaults with blunt objects. Skull fractures ,dural injury,epidural hemotomas are common in this type of injury Brain injury is less severe than that following acceleration injuries.

3 penetrating injuries

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Basilar skull ,the cerebral vascular being particully vulnerable.

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dura and cranial contents penetrated

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missiles more common than sharp projectiles

Pathobiology ●

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The initial impact lead to a number of biochemical alterations. Cellular changes( cellular energy metabolism,cellularblood flow ) Gross changes(edema,hydrocrphalus)

Clinical findings A. symptoms and signs

Patient A ●

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A 21-year-old man was transferred to the hospital 2 hours after suffering ahigh-speed motor vehicle accident with loss of consciousness. Examination:BP 150/90mmhg,the general exmination demonstrated a right parietal laceration. Neurological examination :GCS 7,coma,right-sided weakness, unequal Pupils, left pupill dilated

What is signs of the patient A?

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initial examination

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The initial general trauma assessment should focus on the ABC.

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Next,neurologic examination is done,focusing on the patient’s mental status,(awake,or coma) cranial nerve reflexes, motor function.

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2 Glasgow coma scale （ GCS ） ■

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Mental status is best assessed using the glasgow coma scale. It is the most wodely used neurotrauma scale.

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Three clinical parameters are assessed to determine the patient’s level of consciousness. Eye Opening Motor Response Verbal Response

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Glasgow Scale--Eye Opening ■

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4 = Spontaneous 3 = To voice 2 = To pain 1 = Absent

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Glasgow Scale--Verbal ■

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5 = Oriented 4 = Confused 3 = Inappropriate words 2 = Moaning, Incomprehensible 1 = No response

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Glasgow Scale--Motor ■

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6 = Obeys commands 5 = Localizes pain 4 = Withdraws from pain 3 = Decorticate [di'kɔ:tikeit] 2 = Decerebrate [di:'seribreit] 1 = Flaccid

Her GCS?

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GCS ≤8 ， severe injury GCS 9-12 ， moderate injury GCS 13-15 ， mild injury

3 cranial nerve and reflex assessentt ●

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The extent of cranial nerve examination depends on the patient’s level of consciousness. The most simple and directed examination focuse on three reflexes -----the pulpillary reflex ['pu·pil·lar·y || -----the corneal reflex( 角膜反射） -----the gag reflex （呕吐反射）

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the pulpillary reflex Pupil size, equality, and response to light The reflex reflect the funtion of nerveⅡ Ⅲ

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Unequal Pupils +disturbance of consciousness = – Compression of oculomotor nerve – Probable mass lesion

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Unequal Pupils + Alert patient = – Direct blow to eye, or – Oculomotor nerve injury,

the corneal reflex( 角膜 反射 ） reflect the funtion of nerveⅤ Ⅶ the gag reflex （呕吐 反射） reflect the funtion of nerveⅨ Ⅺ The loss of the corneal or gag reflex indicates severe brain stem injury.

4 assessment of motor funtion ●

Motor Response ■

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Is patient able to move all extremities? How do they move? – Decorticate – Decerebrate – Hemiparalysis 偏瘫 – Paraplegia [pærə‘pli:dʒiə] 截瘫

5 vital signs ●

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Isolated head injury will NOT cause hypotension in adult Look for another life threatening injury – Chest – Abdomen – Pelvis – Multiple long bone fractures

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Vital Signs ■

Cushing’s reflex suggests increased intracranial pressure – Increased BP – Decreased Pulse – Irregular respiratory pattern

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Respiratory Patterns ■

Cheyne-Stokes 潮式呼 吸 – Diffuse injury to cerebral hemispheres

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Central neurological hyperventilation – Injury to mid-brain

Clinical findings B. Imaging studies

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CT is fast,easy,readily available in any hosiptal.

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If the patient is stable, MRI can be used to establish the severity of injury.

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MRI cannot be performed in patient with implanted metalic.

Epidural hematoma:always underlie a skull fracture

Epidural hematoma:always underlie skull fracture subduralahematoma

Intracerebral hemotoma

Medical treatment

A. hemodynamic instability • Should be treated with rapid and aggressive volume resuscitation. • Pressor agent must be used if hypotension • Red blood cells and whole blood shoud be given

• Airway ventilation and oxygenntion must be rapidly assessed and secured. • If necessary , tracheotomy [træki'ɔtəmi] .

B. Neurolgic instability Intracranial mass lesion result in

Intracranial hypertension result in

Neurologic instability

Intracranial hypertension The treatment of intracranial hypertension aim at lowering CSF,brain, and blood volume.

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How to lowering CSF volume?

By use of a ventriculostomy!

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How to lowering brain volume?

lobectomy mannitol hypernatremia [haipənə'tri:miə]

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Mannitol (Osmitrol®) –Drawing interstitial water out of the brain –Decreases cerebral edema –May cause hypovolemia –Often reserved for herniation

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How to lowering blood volume?

capillary volume

no approach Elevating the head of the bed

venous volume Prevent increased intrathoracic pressure

arterial volume

increasing tissue PH

seizures ●

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Should be treated with anticonvulsant medication If seizures stop, discontinued at 7days. If seizures develops after anticonvulsants are stopped, they should be reinstituted for at least 6months.