Neuro Flashcards
Three layers surrounding brain
Meninges
Arachnoid
Pia mater
Anatomical part often implicated in stroke
Circle of willis at base of brain
What three things would alter the blood-brain barrier?
- Head trauma
- Cerebral edema
- Cerebral hypoxia
How long is the spinal cord?
18”
Where does the spinal cord end?
L1
Where are epidurals / spinal anesthesias placed?
L3
When would you use an MRI / MRA to look at neuro stuff?
Non-acute situations (can take 30-90 minutes, looks at circulation)
When would you use a cat scan to look at neuro stuff?
For emergencies – dx stroke, type of stroke
When is an EEG used with neuro stuff? (3)
- Diagnose seizures
- Screen for coma
- Helps determine brain death
When is a spinal tap indicated?
When Cerebral Spinal fluid needs to be assessed for contents or pressure
Pressure reading of CSF (normal
1-15 cmH20
70-200 mmHg
3 minor complications of a lumbar puncture
- Headache
- Voiding problems
- Backache
3 Major complications of a lumbar puncture
- Herniation of cerebral contents
- Infection
- Hematoma
Indication for a blood patch
CSF leakage
Structural causes of neurologic dysfuncction (5)
- Head injury
- Intracranial hemorrhage
- Encephalitis
- Brain abcess
- Stroke
Metabolic causes of neurologic dysfunction (9 - don’t memorize)
- Sepsis
- Hypovolemia
- MI
- Respiratory arrest
- Hypoglycemia
- Electrolyte imbalance
- Drug and / or alcohol abuse
- DKA
- Hepatic encephalopathy
Goals for a patient with neurologic dysfunction
QUALITY OF LIFE for patient and family
Intracranial pressure is a reflection of 3 relatively fixed volumes:
- The brain
- CSF
- Blood
Closed Box Theory (Munro-Kellie Hypothesis)
Any increase in ICP within an intact skull results in a compression or decrease in one of the other compartments (Brain, Blood, CSF)
3 possible causes of increased brain volume:
- Tumor
- Bleed
- Abcess
3 possible causes of increased blood volume:
- Hypertension
- Increase in blood flow
- Decrease in venous return from the head
2 possible causes of increased CSF
Hydrocephalis
Obstruction of outflow of CSF
Define Hydrocephalis
Increased production of CSF
Blood levels that contribute to increased intracranial pressure (2)
- Hypercapnia: PaCO2 > 45
* Hypoxemia: PaO2 < 50
7 factors contributing to increased increased intracranial pressure (7 - not blood levels)
- Valsalva maneuver:
- Positioning
- Isometric muscle contractions:
- Coughing, sneezing
- Emotional upset
- Noxious stimuli (suctioning, starting IVs, any painful procedure)
- Excessive sensory stimuli
Risk with ICP
Brain stem herneating: Can lead to irreversible anoxia, death
Characteristics of a patient with increased ICP (5)
- Lethargy
- Confusion
- Obtundation
- Stuporous
- Comatose
Six early warnings of increased intracranial pressure - 6 sixs
(which is earliest?)
1) Change in LOC or behavior **Earliest sign! Extremely sensitive to decrease in oxygenation
2) Pupils react sluggishly
3) Motor function
4) Constant headache – not a reliable sign
5) VS
6) Visual disturbances
What vital signs would be off in a patient experiencing early intracranial pressure?
- Tachycardia
- Hypertensive swings
5 sxs of a late picture of ICP
1) LOC becomes stuporous or comatose
2) Loss of rain stem reflexes (corneal, pupillary)
3) Characteristic motor response
4) Vital signs off
5) Projectile vomiting
When is death inevitable with ICP?
When pupils are fixed and dilated
Three characteristic motor responses of ICP
- Decorticate
- Decerebrate
- Total flaccidity
What does a decorticate position look like?
Arms up “toward the core”
Feet are flexed and pointed
What does a decerebrate position look like
Arms at side, hands flexed and pronated
Feet are flexed and pointed
What does a decorticate position indicate?
Hemisphere damage
What does a decerebrate position indicate?
Mid brain damage
What does total flaccidity indicate?
Lower brain damage (worst prognosis)
What vital signs would be off with a late-picture ICP patient?
Cheyne stokes respirations (intermittent apnea and irregular)
What tool is used to monitor ICP
Intraventricular catheter in lateral ventricle
Nursing interventions with ICP
1) Monitor ICP
2) Decrease cerebral edema
3) Maintain cerebral perfusion
4) Reduce CSF and blood volume
5) Control fever
6) Reduce metabolic demands
7) Maintain a patent airway
8) Improve cerebral tissue perfusion
9) Monitor fluid balance
10) Prevent infection
11) Monitor for complications
To maintain cerebral perfusion, what would you do if pressure is low? (2)
- Administer fluid
- Positive inotropic agents
To maintain cerebral perfusion, what would you do if pressure is high?
- Decrease fluids
- Administer vasodilators
What would you do to control fever in an increased ICP patient?
- Acetaminophen
- Cooling blanket - no shivering
What drug would decrease shivering
Thorazine
What paralyzing agent would decrease metabolic demands with ICP?
Norcuron
When would you give a patient Norcuron
Only if they are in the ICU and on a ventilator - it paralyzes their breathing!
PEEP with ICP? and - why?
DO NOT USE PEEP because it increases thoracic pressure and can decrease venous return from the head!
Patient position to improve cerebral tissue perfusion
- Keep head midline (no tilting forward)
- Elevate the head of the bed 30 degrees
What could Cheyne-Stokes respirations indicate?
Brain lesion
What could hyperventilation indicate?
Brain or metabolic injury
Head injury: Patient is PERRLA. What could this indicate?
Injury is toxic or metabolic
Head injury: Pupils are unequal. What could this indicate?
Pupils are localizing.
Head injury: Pupils are dilating. What could this indicate?
ICP or brain injury
If blink reflex is unilateral, what type of brain injury is this?
Local
Stiff neck could indicate
Subarachnoid heme meningitis
3 measurements of the glascow coma scale
- Eye opening
- Motor response
- Verbal response
Most common type of complication with head injuries
RESPIRATORY
Three respiratory complications with head injury
- Pneumonia
- Aspiration
- Respiratory infection
Transient cerebral ischemia timing
Within 24 hours (new research = 3-6 hourse)
How often does TIA lead to stroke?
20% (within a few years)
Most common risk factors for CVD (6)
- Cardiovascular Disease
- HTN
- DM
- Smoking
- Family history of CVA
- Sedentary lifestyle
o Temporary episode of neurological dysfunction manifested by a sudden loss of motor, sensory or visual function
TRANSIENT ISCHEMIC ATTACK (TIA)
What do you use to assess a TIA (3)?
- Auscultate carotid arteries
- Carotid Doppler study
- Carotid angiogram
Stroke risk: Racial disparities
2x more likely in blacks
Acronym to recognize a stroke
Face
Arms
Speech
Time
Two general causes of CVA
- Ischemia
- Hemorrhagic
Risk factors for Ischemic CVA (3)
- AFib (#1)
- Ateriosclerosis
- Heart valve disease
Risk factors for hemorrhagic CVA (4)
- Uncontrolled HTN
- Arteriovenous malformation
- Intracranial aneurisms
- Anticoags
What % of CVAs are hemorrhagic?
10-20%
Define Hemianopsia
Partial loss of visual field
CVA: 3 visual field manifestations
Hemianopsia
Loss of peripheral vision
Diplopia
CVA: 5 motor manifestations
Hemiparesis Hemiplegia Ataxia Dysarthia Dyspagia
CVA: 2 sensory manifestations
Paresthesias
Problems with proprioception
CVA: 3 forms of aphagia
Expressive: Can’t express language
Receptive: Can’t understand language
Global: Both receptive and expressive
CVA: 4 cognitive manifestations
Memory loss
Decreased attention span
Can’t concentrate
Poor reasoning, altered judgment
CVA: 5 emotional manifestations
- Loss of self-control
- Emotional lability
- Decreased tolerance to stress
- Depression, withdrawal, feeling of isolation
- Fear, hostility, anger
3 characteristics unique to left hemisphere CVA
Aphasia (right handed people)
Altered intellectual ability
Slow, cautious behavior
3 characteristics unique to right hemisphere CVA
Spacial, perceptual deficits, very distractible
Impulsive behavior and poor judgment
Lack of awareness of deficits
Two characteristics common of either hemisphere CVAs
- Same-sided paralysis or paresthesias
- Deficit in same-sided visual field
Medical management for ischemic stroke (2)
- Thrombolitic therapy
- Anticoagulants
Medical management for hemorrhagic stroke
- Manage ICP
- Surgery
3 common CVA complications
- Cerebral hypoxia
- Decreased cerebral blood flow
- Extension of the area of injury
What would cause extension of the area of injury (CVA)
hyper or hypo tension
Craniotomy: Indications (4)
- Remove clot
- Relieve intracranial edema
- Remove tumor
- Control hemorrhage
Craniotomy: C&DB Patient teaching
o Deep breathing good
o Coughing not good
Craniotomy: Anticonvulsant meds (2)
How long administered?
o Often continued for 6 months to a year (discontinue if no seizures at that point)
o Dilantin, phenobarbitol
Drugs to reduce cerebral edema - craniotomy (2)
steroids
diuretics
Craniotomy: Complications to assess for and avoid (6)
o Increased ICP o Bleeding at operative site o Fluid and electrolyte embalances o Infection o Seizures
Decreased mental status: Craniotomy
o Common: Decreased mental status 2nd day 2/2 swelling.