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Alterations of Neurologic Function. Chapter 15. Brain Trauma. Major head trauma A traumatic insult to the brain possibly producing physical, intellectual, emotional, social, and vocational changes Transportation accidents Falls Sports-related event Violence. Brain Trauma. - PowerPoint PPT Presentation
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Alterations of Neurologic Function
Chapter 15
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Brain Trauma
Major head trauma A traumatic insult to the brain possibly
producing physical, intellectual, emotional, social, and vocational changes
Transportation accidents Falls Sports-related event Violence
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Brain Trauma Closed (blunt, nonmissile) trauma
Head strikes hard surface or a rapidly moving object strikes the head
The dura remains intact and brain tissues are not exposed to the environment
Causes focal (local) or diffuse (general) brain injuries
Open (penetrating, missile) trauma Injury breaks the dura and exposes the cranial
contents to the environment Causes primarily focal injuries
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Brain Trauma Coup injury- impact against an object(front of
skull) Injury directly below the point of impact
Contrecoup- impact within skull( front and back of skull) Injury on the pole opposite the site of impact
Compound fractures Basilar skull fracture
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Brain Trauma
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Focal Brain Injury Observable brain lesion Force of impact typically produces contusions Contusions can cause:
Extradural (epidural) hemorrhages or hematomas bleed between the dura mater , artery is usually the source of bleed, classically loose consciousness at injury,
Subdural hematomas-common in elderly or alcohol abuse, can be acute usually top of skull or chronic
Intracerebral hematomas – most common frontal and temporal lobes and associated with contusions, + bilateral Babinski reflex, ICP increased
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Hematomas
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Subdural (Epidural) Hematomas
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Diffuse Brain Injury
Categories: Mild concussion Classical concussion Mild, moderate, and severe diffuse axonal
injuries (DAI) • Shaking• Acceleration/deceleration• Axonal damage• Severity corresponds to the amount of shearing force
applied to the brain and brain stem
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Mild Concussion
Temporary axonal disturbance causing attention and memory deficits but no loss of consciousness I: confusion, disorientation, and momentary
amnesia momentary II: momentary confusion and retrograde
amnesia 5-10 min III: confusion with retrograde and anterograde
amnesia lasting less than 6 hours
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Classic Cerebral Concussion Grade IV
Loss of consciousness (<6 hours) reflexes fail, causing falls symptoms disappear after responsiveness returns. Transient breathing stops, bradycardia occurs and BP falls. Vitals quickly stabilize
Anterograde and retrograde amnesia may last for hours to days
Postconcussive syndrome- HZ+A< nervousness, anxiety, irritability, insomnia, depression forgetfulness inability to consentrate
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Diffuse Axonal Injury Produces a traumatic coma lasting more than 6
hours because of axonal disruption Mild –prolong periods of stupor or restlessness Moderate – unconsciousness for weeks usually
permanent memory defect ,Glasgow coma scale 4-8 Posttraumatic antergrade and retrograde amnesia Severe- ICP appears 4-6 days post injury . Severely
Compromised movements, verbal and written communication problems , autonomic dysfunction
Should know DIA consequences p.181 Must look for secondary problems due to brain injury
such as changes in neurotransmitters and electrolytes, breaking of blood brain barrier causing IICP
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Spinal Cord Trauma Most commonly occurs due to vertebral injuries
Simple fracture, compressed fracture, and comminuted fracture and dislocation ,very common in elderly due to degeneration
Traumatic injury of vertebral and neural tissues as a result of compressing, pulling, or shearing forces , swelling temporarily increases dysfunction
Most common locations: cervical (1, 2, 4-7), and T1-L2 lumbar vertebrae Locations reflect most mobile portions of vertebral column
and the locations where the spinal cord occupies most of the vertebral canal injury worse at the level of injury and below
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Spinal Cord Trauma
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Spinal Cord Trauma
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Spinal Cord Trauma
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Spinal Cord Trauma
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Spinal Cord Trauma Spinal shock
Normal activity of the spinal cord ceases at and below the level of injury. Sites lack continuous nervous discharges from the brain.
Complete loss of reflex function (skeletal, bladder, bowel, sexual function, thermal control, and autonomic control) below level of lesion( hypothalamus can not control body heat thru vasoconstriction , now have increased metabolism so patient assumes temperature of surrounding air(poikilothermia)
Cervical spinal injury worse due to injury of diaphragm ( phrenic nerve that exit cord at C3-C5
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Spinal Cord Trauma Paraplegia Quadriplegia Autonomic hyperreflexia (dysreflexia) PRIORITY
QUESTION Massive, uncompensated cardiovascular response to
stimulation of the sympathetic nervous system Stimulation of the sensory receptors below the level of the
cord lesion SS= Increase BP systolic , pounding HA, blurred vision,
sweating above level so lesion , skin flushing, nasal congestion, nausea ,poiloerection caused by pilomotor spam and Bradycardia. Often associated with extended bladder and rectum.
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Autonomic Hyperreflexia
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Degenerative Disorders of the Spine
Degenerative disk disease (DDD) Spondylolysis- defect in vertebral lamina Spondylolisthesis- vetabra slides forward on the
vertebra below( 4 grades of anterior slipage) Spinal stenosis-narrowing of spinal canal causing
spinal cord pressure Low back pain-80% of population Herniated intervertebral disk most common
L4 – S1
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Cerebrovascular Disorders Cerebrovascular accident
Leading cause of disability Third leading cause of death in United States Classified
• Global hypoperfusion- as in shock• Ischemia (thrombotic, embolic)• Hemorrhagic• Know factors who has increase likelihood of having stroke?
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Cerebrovascular Disorders Cerebrovascular accidents (CVAs)
Thrombotic stroke• Arterial occlusions caused by thrombi formed in
arteries supplying the brain or in the intracranial vessels( atherosclerosis) break off and travel upstream. Causes – dehydration, hypotension, prolonged vasoconstriction
• Transient ischemic attacks (TIAs)-temporarily decrease brain blood flow. Brief change in brain function-vision, speech, motor function, dizziness of loss of consciences- neurologic defects disappear in 24 hours
Embolic stroke• Fragments that break from a thrombus formed
outside the brain
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Cerebrovascular Disorders
Embolic stroke• Fragments that break from a thrombus formed outside
the brain , heart ,aorta, common carotid. Risk factors MI, aerial fib, endocarditis, Rheumatic Ht. Dz., atria-septal-defect.
Hemorrhagic stroke-hypertension , rupture aneurysms Lacunar stroke- Smoking, hypertension and DM Cerebral infarction- brain looses blood supply because of
vascular occlusion. Types are ischemic or hemorrhagic Cerebral hemorrhage- primary cause is hypertension
resulting in thickenig of vessels walls
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Cerebrovascular Disorders
Clinical manifestations Excruciating HA . Weakness, transient numbness and
tingling transient speech disturbance Signs- hemiparesis/paralysis, dysphasia,
homonymous hemianopsia(Same side of stroke eye blindness)
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Cerebrovascular Disorders
Intracranial aneurysm Congenital Diffuse arteriosclerotic changes
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Intracranial Aneurysm
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Cerebrovascular Disorders
Subarachnoid hemorrhage Blood escapes from defective or injured
vasculature into the subarachnoid space Manifestations
Kernig sign- in sitting position have patient straighten knee , if has pain in neck and back = +
Brudzinski sign- passive neck flexion produces pain and rigidity
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Infection and Inflammation of the CNS
Meningitis Bacterial meningitis Aseptic (viral, nonpurulent, lymphocytic) meningitis Fungal meningitis Tubercular (TB) meningitis
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Infection and Inflammation of the CNS
Encephalitis Acute febrile illness, usually of viral origin with
nervous system involvement Most common forms of encephalitis are caused
by arthropod-borne viruses and herpes simplex virus
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Neurologic Complications of AIDS
Human immunodeficiency-associated cognitive dysfunction
HIV myelopathy HIV neuropathy Aseptic viral meningitis Opportunistic infections CNS neoplasms
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Demyelinating Disorders Multiple sclerosis (MS)- autoimmune disorder. Onset 20-
50 yrs old MS is a progressive, inflammatory, demyelinating axon
disorder of the CNS- spares peripheral nervous system. Has exacerbations and remissions. Starts on one side of body, loss of strength and grip, diplopia, hyper-reflexia foot drag and stumbling. Lhermitte sign- shocking and tingling sensations. Heat and increase serum Ca+ bring on symptoms
MRI definitive test All motor function eventfully lostAmyotrophic lateral sclerosis (ALS)- muscle wasting Dz, Onset 4—50 ys. Can be familiar. Classic bulbar palsy
and muscular atrophy
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Peripheral Nervous System Disorders
Amyotrophic lateral sclerosis (ALS) Classic ALS—“Lou Gehrig disease” Diffusely affects upper and lower motor
neurons of the cerebral cortex, brain stem, and spinal cord (corticospinal tracts and anterior roots)
Disease leads to progressive weakness leading to respiratory failure and death
Patient has normal intellectual and sensory function until death
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Peripheral Nervous System Disorders
Neuropathies Generalized symmetrical polyneuropathies
• Distal axonal polyneuropathy• Demyelinating polyneuropathy
Generalized neuropathies• Sensory neuropathies
Focal or multifocal neuropathies
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Peripheral Nervous System Disorders
Guillain-Barré syndrome Acquired inflammatory disease causing
demyelination of the peripheral nerves with relative sparing of axons
Acute onset, ascending motor paralysis Humoral and cellular immunologic reaction
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Peripheral Nervous System Disorders
Myopathies- Primary muscle disorder Marked weakness
Symmetrical and proximal Radiculopathies Radiculitis- sciatica , herpes zoster
• Inflammation of the spinal nerve roots Radicular pain – following dermatome pattern
Plexus injures- cCrvical C1-5. Brachial C6-8, Lumbar T12- S2 Involves the nerve plexus distal to the spinal roots but
proximal to the formation of the peripheral nerves
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Neuromuscular Junction Disorders
Myasthenia gravis Chronic autoimmune disease . Nerve impulse
transmission to neuromuscular junction is interrupted
Muscle weakness and fatigue of muscles of the eyes and the throat causing diplopia, difficulty chewing, talking, swallowing
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Central Nervous System Tumors
Cranial tumors Spinal cord tumors