Neurologic Trauma Flashcards
What are the most common causes of traumatic brain injury?
- falls
- motor vehicle accidents
- collisions w/stationary or moving objects
- assaults
Who is at the highest risk for traumatic brain injury?
- males 15-24 years
- very young
- very old
Primary Traumatic Brain Injury
initial damage to the brain that results from the traumatic event
Primary TBI’s may include what?
- contusions
- lacerations
- torn blood vessels from impact
- acceleration/deceleration
- penetration by foreign object
Secondary Traumatic Brain Injury
evolves over the ensuing hours/days after the initial injury
Secondary TBI’s can be due to what?
- cerebral edema
- ischemia
- seizures
- infection
- hyperthermia
- hypovolemia
- hypoxia
Increased intracranial pressure can cause what?
Herniation of the brain through or against the skull
Herniation of the brain causes what?
- ischemia
- infarction
- irreversible brain damage
- brain death
What are skull fractures?
a break in the skull caused by forceful trauma w/ or w/o brain damage
S/S of Traumatic Brain Injury
- altered LOC
- confusion
- pupillary abnormalities
- sudden onset of neuro deficits
- changes in vitals
- vision/hearing impairment
- headaches
- seizures
When does a Closed (blunt) brain injury occur?
when the head accelerates and then rapidly decelerates or collides w/ another object and brain tissue is damaged but there is no opening
When does an Open brain injury occur?
when an object penetrates the skull, enters the brain, and damages the soft brain tissue in its path or when blunt trauma is so severe it opens the scalp
What is a Concussion?
alteration in mental status that results from trauma and may or may not involve LOC
How long do symptoms of concussions typically last?
24 hours
S/S of Concussions
- headache
- N/V
- photophobia
- amnesia
- blurry vision
Treatment for Concussion
- observing patient for worsening symptoms for next 24 hours
- woken every 2 hours in order to detect changes
- advise to resume normal activities slowly
What is a Cerebral Contusion?
bruising of the brain, w/ possible surface hemorrhage and the patient is unconscious for more than a few seconds or minutes
S/S of a Cerebral Contusion depend on what?
The size of the contusion and the amount of associated swelling of the brain
S/S of Cerebral Contusion
- motionless
- faint pulse
- shallow respirations
- cool, pale skin
If patient recovers consciousness w/ a Cerebral Contusion they may enter a state of what?
Cerebral irritability
What is a state of Cerebral Irritability like?
Patient is easily disturbed by any form of stimulation such as noises, light, and voices; may be hyperactive at times
What are some after effects of Cerebral Contusions?
- residual headache
- vertigo
- impaired mental function
- seizures
Decorticate Posturing
abnormal flexion of the upper extremities and extension of the lower extremities
Decorticate Posturing indicates damage to what part of the brain?
Upper midbrain
Decerebrate Posturing
extreme extension of the upper and lower extremities
Decerebrate Posturing indicates damage to what part of the brain?
lower midbrain and upper pons
What are Hematomas?
Collections of blood that develop w/in the cranial vault
What are the most serious types of brain injury?
Hematomas
Symptoms of hematomas are frequently delayed until when?
The hematoma is large enough to cause distortion of the brain and increased ICP
Where are Epidural Hematomas found?
Space b/t skull and the dura
Epidural Hematomas can result from what?
Skull fracture that causes a rupture or laceration of the middle meningeal artery
Symptoms of Epidural Hematomas are caused by what?
the expanding hematoma
S/S of Epidural Hematoma
- Momentary loss of consciousness occurs at the time of injury followed by an interval of apparent recovery
- increased ICP
- signs of compression
- decreasing LOC
- dilation/fixation of pupils
- paralysis of extremity
Why is an Epidural Hematoma considered an extreme emergency?
B/c marked neurologic deficit and respiratory arrest can occur w/in minutes
Treatment of Epidural Hematoma
- burr holes into skull to decrease ICP, remove clot and control bleeding immediately
- Craniotomy
- drain may be inserted after either procedures to prevent reaccumulation of blood
Where is a Subdural Hematoma located?
Between the dura and the brain a space normally occupied by a thin cushion of CSF
What is the most common cause of Subdural Hematoma?
Trauma
- bleeding disorders
- ruptured aneurysm
Who is at an increased risk for Subdural Hematomas?
Elderly b/c of whole brain atrophy
Acute Subdural Hematoma’s are associated w/ what major head injuries?
Contusion or laceration
How long does it take S/S of acute subdural hematoma’s to develop?
24-48 hours
S/S of Acute Subdural Hematomas
- changes in LOC
- changes in reactivity of pupils
- hemiparesis
What are signs of a rapidly expanding Subdural mass that needs immediate intervention?
- coma
- increasing BP
- decreasing HR
- slowing respiratory rate
What are Subacute Subdural Hematomas?
the result of a less severe contusion and head trauma
-S/S appear b/t 48-2 weeks after the injury
Chronic Subdural Hematomas can develop from what?
Seemingly minor head injuries
Treatment for Chronic Subdural Hematoma
- Surgical evacuation of the clot if the patient is symptomatic and the bleed is at least 1 cm in size
- smaller bleeds are only monitored
Intracerebral Hemorrhage
bleeding into the parenchyma of the brain
Intracerebral Hemorrhage is commonly seen when?
When the force is exerted to the head over a small area
- bullet wounds
- stab injuries
Intracerebral Hemorrhage can also occur when?
- systemic HTN
- rupture of saccular aneurysm
- vascular anomalies
- intracranial tumors
- bleeding disorders
What is the onset of Intracerebral Hemorrhage like?
May be insidious, beginning w/ the development of neuro deficits followed by headache
Management for Intracerebral Hemorrhage
- supportive care
- control of ICP
- careful administration of fluids/electrolytes, and antihypertensive meds
Surgical Intervention for Intracerebral Hemorrhage
- craniotomy
- craniectomy
Why may a craniotomy not be successful w/ Intracerebral Hemorrhage?
Because of the inaccessible location of the bleeding
What are the primary neuroimaging diagnostic tools of choice for evaluating brain injury?
CT and MRI
What patients are at highest risk for Cervical Spine Injury?
- motorcycle accidents
- lower Glasgow Coma Scores
- skull base fractures
Altered LOC is apparent in a patient that demonstrates what?
- who is not oriented
- can not follow commands
- needs persistent stimuli to achieve state of alertness
Coma
clinical state of unarousable unresponsiveness in which there are no purposeful responses to internal or external stimuli
How long is “coma” limited to?
2-4 weeks
Persistent Vegetative State
condition in which unresponsive patient resumes sleep-wake cycles after coma but devoid of cognitive or effective mental function
When is the Cushing Response seen?
When cerebral blood flow decreases significantly
What occurs during the Cushing Response?
When the brain is ischemic the vasomotor center triggers an increase in arterial pressure in an effort to overcome the increased ICP
When the brain’s ability to autoregulate becomes ineffective and decompensation begins the deterioration is known as what?
Cushing Triad
S/S of Cushing Triad
- bradycardia
- hypertension
- bradypnea
S/S of the patient’s state of alertness and consciousness decreasing will occur in what responses?
- pupillary response
- eye opening response
- verbal response
- motor response
Early signs if ICP
- sudden onset restlessness
- confusion
- increasing drowsiness
- pupils become sluggish
Glasgow Coma Scale Criteria
- eye opening
- verbal response
- motor response
- rates on scale from 3-15
What is the lowest a patient can score on the Glasgow Coma Scale?
3 Coma
What is the first priority treatment for the patient w/ altered LOC?
Obtain and maintain patent airway
- patient may be orally or nasally intubated
- tracheostomy
What interventions are performed to decrease ICP, cerebral edema, cerebral blood volume and CSF?
- osmotic diuretics
- restricting fluids
- draining CSF
- maintain BP and O2
- reduce cellular metabolic demands
- control fever
What is the earliest sign of increasing ICP?
Change in LOC
Early indications increasing ICP are?
- disorientation/restless/increased respiratory effort
- pupillary changes
- weakness in one extremity or on one side of body
- headache that is constant
Later S/S of increasing ICP are?
- LOC continues to deteriorate until patient is comatose
- respiratory rate decreases or become erratic (Cheyne-stokes)
- BP/temp increase
- HR goes from brady-tachy
- projectile vomiting
- hemiplegia/decorticate/deceberate posturing
- loss of brain stem reflexes
How can ICP be monitored?
- intraventricular catheter-ventriculostomy
- subarachnoid bolt or screw
Complications from altered LOC
- respiratory failure
- pneumonia
- pressure ulcers
- aspiration
- endocrine abnormalities-diabetes insipidus/SIADH
Diabetes Insipidus is the result of what?
decreased secretion of ADH
Diabetes Insipidus causes what?
- excessive urine output
- decrease urine osmolality
- serum hyperosmolarity
Therapy for Diabetes Insipidus consists of what?
- administration of fluids
- electrolyte replacement
- vasopressin
SAIDH is a result of what?
increased secretion of ADH
What happens w/ SIADH?
Patient becomes volume-overloaded, urine output diminishes, serum sodium concentration becomes dilute
Treatment for minor SIADH
Fluid restriction-typically 1 L/day with no free water
Treatment for severe SIADH
- administration of 3% hypertonic saline solution
- accompanied w/ lasix
Osmotic Diuretics may be administered to do what?
Dehydrate the brain tissue and reduce cerebal edema
- reduce blood viscosity and hematocrit
- enhance cerebral blood flow
What medication is the gold standard in reducing ICP?
Mannitol-osmotic diuretic
What is another medications that may be used to treat cerebral edema?
Hypertonic Saline
Hypotonic fluids should be avoided in what patients?
Patients w/ TBI because they can cause increase in cerebral edema
Why may the patient be hyperventilated to decrease ICP?
As the patient hyperventilates PCO2 rises causing vasoconstriction, decreasing cerebral blood flow, which results in decreasing ICP
What happens when a patient strains with a BM?
it increases intra-abdominal/intra-thoracic pressure which impedes venous return and increases ICP
Decompressive Craniectomy
removal of a bone flap from the skull to allow expansion of the brain
What are the 3 cardinal findings for declaring a patient brain dead?
- coma/unresponsive
- absence of brain stem reflexes
- apnea
Current Criteria for brain death
- condition is irreversible w/ known cause
- not under effect of CNS depressants/paralytics
- no electrolyte/severe acid-base/endocrine abnormality
- has apnea
- no brainstem reflexes
- temp > 90
- systolic BP at least 100
- neuroimaging evidence of catastrophic damage
Primary SCI
result of the initial insult or trauma and is usually permanent
Secondary SCI
usually result of contusion or tear injury in which the nerve fibers begin to swell and disintegrate
Secondary SCI are thought to be reversible for up to how long after the injury?
first 4-6 hours
What is the leading cause of death in high cervical cord injuries?
Acute respiratory failure
Central Cord Syndrome Characteristics
- Motor deficits/sensory loss in upper extremities more than lower
- bowel/bladder dysfunction variable or completely reserved
Causes of Central Cord Syndrome
Injury or edema of central cord, usually of cervical area, may be caused by hyperextension
Characteristics of Brown-Sequard Syndrome (Lateral Cord)
- ipsilateral paralysis, loss of touch, pressure, and vibration
- contralateral loss of pain and temperature
Causes of Brown-Sequard Syndrome
transverse hernisection of the cord usually as a result of a knife or missile injury, fracture-dislocation, acute ruptured disc
Anterior Cord Syndrome Characteristics
- loss of pain, temperature, and motor function are noted below level of lesion
- light touch, position, and vibration remain intact
Causes of Anterior Cord Syndrome
- acute disk herniation
- hyperflexion injuries from fractures-dislocation
- anterior spinal artery
Why is continuous cardiac monitoring indicated for SCI?
B/c bradycardia and asystole are common
Treatment for SCI attempt to achieve what?
Decompression, stabilization, and realignment of the spinal cord while preserving or improving neuro function
Surgery is indicated for what situations w/ SCI?
- compression of cord
- fragmented or unstable vertebral body
- penetrating wound to spinal cord
- bone fragments in spinal canal
- deterioration of neuro status
Pin Care for patient in Halo Device Traction
- cleaned daily
- observed for redness, drainage, and pain
- observe for loosening
- keep torque screw driver at bedside
What should the nurse do if pin comes out of Halo Device?
One nurse should stabilize head in neutral position while the other calls neuro surgeon
