Class 15 - Alterations in Neuro - Trauma Flashcards
Traumatic Brain Injury
Causes
- Motorcycle, motor vehicle collisions, blunt force trauma, sports, falls and child abuse
Groups at risk
- Children (under 14), males, adults over 65
- Male groups have a higher incidence 70%
Mechanisms of TBI
Penetrating injury (open)
- Skull is not intact
- Skin is not intact
- Brain/meninges exposed
Blunt injury (closed)
- No external damage evident
- Skull remains intact
- Brain/meninges not exposed
Focal Injuries
- Generally associated with a direct impact to the head
- Specific localized injuries to the brain
Skull fractures
- Linear
- Depressed
- Increase of intracranial pressure due to less space - Basilar (Basal)
- Base of skull
- CSF leak from nose or ear, associated with the tearing or damaging of meninges
- Periorbital bruising
- Battle’s sign (bruising behind the ears)
Contusions
- Bruising of brain tissue
- Frequently located on frontal and temporal lobes
- Manifestations: depends where the bruises are
- Coup-countrecoup: frontal - occipital lobe, temporal - temporal
Hematomas
- Epidural
- Outside the dura mater
- Arteries bleed faster than veins, this contusion bleeds faster than others
- Develop fast, deteriorate fast - Subdural
- Arachnoid, beneath the dura mater - Intracranial
- Intracerebral
Diffuse Injuries
Widespread, not limited to localized area
- Difficult to detect and treat, doesn’t show up on CT scans
1. Concussion
2. Diffuse Axonal Injury
Concussion
Transient neurlogical dysfunction due to a traumatic impact
Types
1. Mild concussion - no loss of consciousness
2. Classic Cerebral Concussion - loss of consciousness up to 6 hours
Manifestations
- Headache
- Confusion
- Disorientation
- Dizziness
- Visual disturbances
- Possible loss of consciousness
- Memory deficits
- Retrograde amnesia (loss of memory from before the event)
- Anterograde amnesia (Unable to create new memories)
Post concussive syndrom
- Headache, anxiety, irritability, insomnia, difficulty concentrating
Chronic Traumatic Encephalopathy (CTE)
Post concussion
Progressive degeneration of brain tissue
Accumulation of abnormal protein (tau) brown proteins
- People with Alzheimer’s also have high levels of tau
Diffuse Axonal Injury
Diffuse damage to axons
- Stretching or shearing of neuronal axons
Mechanism of Injury
- Acceleration/deceleration, rotational
Results
- Outcomes unpredictable
- High morbidity and mortality have been associated
Shaken Baby Syndrome
- Big head, weak neck muscles puts infants at risk
Potential Long-term Outcomes of TBI
Full recovery is possible
Impact on family, job, social and community interactions
- Cognition, memory, attention, emotions, personality, behaviour, social skills
- Speech, comprehension disorders
1. Aphasia: impaired speech
2. Dysphagia: abnormal speech
3. Agnosia: inability to interpret sensory input
Recovery with residual disability
- Depression, anxiety, disability
- Motor function, posture, muscle tone, gait, swallowing
1. Dyskinesia, akinesia, hyperkinesia, bradykinesia
2. Hypertonia, hypotonia (muscle tone)
3. Dysphagia - swallowing Gia - GI tract
Long-term changes in level of consciousness
- Persistent vegetative state(sleep wake, open eyes, look around, no interaction)
- Irreversible coma = cerebral death (death of the cerebrum, no awareness, permanent coma, still alive because of brain stem)
- Brain death (brain stem and cerebral cortex are dead)
Autonomic Dysreflexia
- A complication of spinal cord injury above T6
- Associated with disconnect between with SNS and PNS
- Hypertension above the injury. Triggers baroreceptors
- Bradycardia and vasodilation
- Parasympathetic response - Vasoconstriction below the injury causes increased blood volume above the injury
- Shunts it up
- Sympathetic response - Noxious Stimulus - major SNS response, vasoconstriction
- At risk for: stroke, having the blood vessels rupture due to high blood pressure
- Treatment: get rid of stimulus and use medications to bring down the blood pressure
Spinal Cord Injuries
At risk: elderly because of normal age related change, males
Mechanisms of Injury
- Flexion: when you have momentum
- Extension: hit from behind, hitting chin on a coffee table
- Compression: something falling on your head, or falling straight onto head or tailbone
- Flexion - rotation: typical for motor vehicle
Pathophysology
- Cellular injury, inflammation, edema, decreased tissue perfusion, tissue hypoxia, necrosis, scarring
- Edema at level of injury and 2 cord segments above and below
Classifications of SCI, level of injury
- Cervical, thoracic, lumbar, sacral
0 Quadriplegia (paralysis of 4 limbs), paraplegia (2 limbs)
Complications of SCI
Neurogenic
- Results in profound vasodilation
- T6 or above
- Blood pressure drops
- Bradycardia - due to interruption of sympathetic response
Respiratory Failure
- C4 and above affects the diaphragm
- Autonomic Dysreflexia
- Bowel / bladder / sexual dysfunction
- Pressure ulcers
