Neuro Flashcards
Pressure of blood flowing into the brain
cranial perfusion pressure (CPP)
Totality of all pressures in the brain (BP, CSF, brain tissue)
intracranial pressure (ICP)
Concept map of imbalance of pressure (ICP or CPP)
ineffective perfusion > ischemia > cellular hypoxia > cell injury/death > increase cellular permeability > cerebral edema & increased ICP > further loss of effective perfusion
The main culprit in causing increased ICP
cerebral edema
Any disruption of normal blood flow to any part of the brain resulting in damaged brain tissue
brain attack/Stroke
Most common etiologies of BA
atherosclerosis of incoming arteries
HTN
Brain aneurysms
Problems of decreased CO
Risk factors for Stroke
HX of atherosclerosis or HTN Old age Family HX Diabetes Lifestyle (smoking & high fat diet)
Underlying mechanism(s) of stroke
Ischemia
Hemorrhage
80% of all stroke are ___ in nature
ischemic
Ischemic strokes are usually related to ___ and other processes that cause ___
atherosclerosis; arterial wall damage & plaque formation
Ischemic strokes may be __ or __ in nature
thrombotic or embolic
Risk of ischemic stroke increases X5 with ___
Hx of afib
Thrombotic or Embolic events that cause stroke:
Carotid atherosclerosis
Air emboli
Clots around mitral/aortic valve prosthesis
Intracranial artery plaque (circle of Willis)
BA that resolves within 24 hours with no neurologic deficits
TIA
Usually caused by a blood clot that leaks out directly onto brain tissue
Hemorrhagic stroke
Causes of Hemorrhagic stroke
HTN pressures Weakened arterial walls Aneurysms Congenital vascular malformations Bleeding into a tumor Coagulation disorders
S/S of stroke depend on __
where the stroke is occurring
3 regions where stroke can occur
Hemispheres
Cerebellum
Brain stem
Abnormalities in sensorimotor findings occur ___
contra-laterally to where the bleed is occurring
Normal sensorimotor findings should be __
symmetrical
Visual deficit that indicates cerebral edema around the CN II
homonymous hemianopia (visual deficit in left halves of both eyes)
Sensorimotor findings below the shoulders indicate perfusion status of ___
corticospinal & spinothalmic tracts
Focal lesions in the spinal tracts would present with ___
asymmetric changes on the contralateral side of the body
Flexion of the big toe in response to stroking the plantar surface of the foot
positive Babinski’s sign
Cerebellar stroke occur due to occlusion of ___
vertebral-basilar arteries
Some S/S of cerebellar stroke
balance problems/falls loss of coordination vertigo nystagmus N/V
Typical S/S of a cerebral hemispheric stroke
Sensorimotor deficits
Deficits based on special functions of that hemisphere
Left hemisphere specific stroke deficits
Speech
Cognitive ability
Left hemisphere specific stroke deficits affecting speech
aphasia/dysphasia, comprehension, expression
Left hemisphere specific stroke deficits affecting cognitive ability
math, organization, reasoning, analysis
Right hemisphere stroke deficits:
Spatiality left-sided neglect Insight (introspect) Creativity Face recognition Musical ability
Hemorrhagic stroke typically causes the PT to experience
intense headaches
Neck pain
Light sensitivity
N/V
Immediate nursing interventions for BA
O2
manage BP
Monitor/control cerebral edema (head of bed @ 30º
S/S of bacterial meningitis
Meningeal edema Increased ICP Photophobia Headache Restlessness Decreased LOC N/V Neck stiffness
bacterial meningitis can present with these skin conditions
Petechiae, Purpura
Types of Alzheimer’s dz
Familial Alzheimer’s (FAD)
Sporadic (non-hereditary)
3 assessment points for stroke
LOC/VS (autonomic)
Sensorimotor status
Reflexes
Alzheimer’s is thought to be caused by:
genetic mutation of amyloid proteins that results in abnormal amyloid accumulation which forms plaque-like material
Plaque-like material formed by abnormal accumulation of amyloid in Alzheimer’s patients
senile plaques
Formation of twisted microtubules of brain neurons
neurofibrillary tangle
Senile plaques & neurofibrillary tangle combine and ___
disrupt normal nerve impulses in the brain
Clinical manifestation of Alzheimer’s
dementia
Motor changes if posterior frontal lobe involvement
Parkinson’s dz involves negative effects on this anatomical structure ___
extrapyramidal motor tracts
the Extrapyramidal system is responsible for:
fine motor movements
Normal basal ganglia function depends on ___
ACh (acetylcholine) & dopamine
Acetylcholine has an ___ effect on ACh receptors that initiate movement
excitatory
An excitatory effect of a neurotransmitter is also called a ___ effect
Cholinergic
Dopamine has a __ effect on ACh receptors that initiate movement
inhibitory
Parkinson’s is a ___ dysfunction
basal ganglia
The cause of Parkinson’s is thought to be:
genetic, viral, or environmental toxin-induced depletion of dopamine
A decrease in dopamine disrupts ___ causing ___
the balance of neurotransmitter effects, causing acetylcholine to have a stronger effect
Increased __ effects of dopamine depletion causes the S/S of Parkinson’s
cholinergic
S/S of Parkinson’s are related to ___
hypertonia & dyskinesia
S/S of Parkinson’s are dubbed “___”
Parkinsonianisms
Inability of Parkinson’s PTs to adjust posture when tipping or falling results in what is termed ___
Basal Ganglion gait
Medications that treat S/S of Parkinson’s include medications that:
contain Dopamine to counter the neurologic decrease;
have anti-cholinergic effects (Benadryl)
Common autoimmune disorder with onset between ages 20-50, that effects women 2X more than men
Multiple Sclerosis
The name “Multiple Sclerosis” is based on the pathology of MS, in which:
T cell attacks causes demyelination in multifocal (“multiple”) locations, which heals by forming scar tissue that hardens over time (sclerosis)
___ are effected by the scarring & hardening of MS
neuroglia
Demyelinated nerve axons transmit impulse ____ compared to normal axons
10X slower
Hemorrhagic stroke is caused by ___
the effects of blood leaking directly onto brain tissue, causing inflammatory processes
A diffuse brain/brain stem stroke is caused by an event that causes ___
the whole brain to become hypoxic and edematous with increased ICP
S/S of MS
Paresthesias
Asymmetrical weakness
balance/coordination issues if cerebellum involved
Severe episodic headaches that occur in a typical pattern
Migraines
Common pattern of a migraine
Prodrome
Headache
Postdrome
Migraines are thought to be caused by
a trigger event in genetically predisposed people
Triggers of migraines can include:
chemicals in certain foods (cheese, wine, chocolate)
or stressful events, smells, sounds, etc.
Medication taken at the first sign of a migraine prodrome
Immitrex (abortive drugs)
Define Dementia
chronic dysfunction of memory and/or function that develops over time
Types of events that can contribute to a thrombotic or embolic stroke
Afib
Carotid atherosclerosis
air emboli
clots around mitral/aortic valve prosthesis
Development of intracranial artery plaque
The corticospinal tracts function to:
carry impulses that produce voluntary skillful movement from the brain
Define Nystagmus
rhythmic, involuntary, unilateral or bilateral movement of the eyes
Sudden, explosive, disorderly discharge of brain neurons that cause transient alteration in brain function
seizure
Seizures can be caused by ___
congenital seizure disorder (epilepsy)
or
an acute problem
Examples of acute problems that can cause seizures
head injury
stroke
Infection/inflammation of the meninges
meningitis
___ meningitis almost never causes sepsis
viral
Meningitis is most commonly caused by:
viruses or bbacteria
Most common cause of bacterial meningitis
meningococcus & pneumococcus
___ meningitis causes worse S/S and clinical picture than ___
bacterial; viral
S/S of meningeal inflammation around the brain
photophobia blurred vision headache restlessness irritability decreased LOC
S/S of meningeal inflammation around the spinal chord
neck stiffness
positive Brudzinski’s and/or Kernig’s signs
Other more generalized S/S of meningitis
fever
leukocytosis
petechiae & purpura
Petechiae & purpura in meningitis is caused by
bacterial toxins inflaming subdermal vasculature
Diagnosis of meningitis is done by ___
CSF analysis via spinal tap
CSF is analysis when suspecting meningitis would bee focusing on looking for:
high WBC
high protein count
lower than normal glucose
Blood
The synapse between the neuron & the effector muscle
neuromuscular junction
NMJ functions involve:
balance of events that result in muscle movement
Some functions of the NMJ resulting in muscle movement include:
releasing ACh
binding ACh to ACh receptors
Releasing cholinesterase
Cholinesterase functions to __
break down leftover ACh that isn’t used
anything that decreases ____ and/or increases ___ results in muscle weakness
ACh production/reception
Cholinesterase production
___ is an example of a disorder of the NMJ
Myasthenia Gravis
Thymic tumor or other changes in the thymus are sometimes associated with this autoimmune dz
Myasthenia Gravis
The causative action in Myasthenia gravis
self-produced antibodies block, alter, or destroy ACh receptors
S/S of Myasthenia Gravis
Progressive muscle weakness that increases during periods of activity & decreases during rest
Pathology of progressive muscle weakness during motor activity (Myasthenia Gravis)
Autoantibodies destroy ACh receptors, so even normal reductions in ACh quickly result in inability to complete the nerve transmission
Muscle weakness in Myasthenia Gravis can include muscles that control ___
eye/eyelid movement, facial expressions, chewing, talking, swallowing, and neck/limb movements
Medication based TX for Myasthenia gravis include:
Anti-cholinesterase drugs
Steroids
Pupillary dilation upon exposure to less light
mydriasis
Mydriasis results from ___
the sympathetic nervous system secreting norepinephrine & stimulating alpha-1 adrenergic receptors
Mydriasis is a(n) ___ effect
adrenergic
Pupillary constriction
miosis
Miosis results from ___
parasympathetic nerve fibers in CN II releasing ACh
Miosis is a(n) ___ effect
cholinergic
“same side” effect
ipsilateral
Double vision
diplopia
Inflammation/edema of the optic nerve
Papilledema
Papilledema is caused by
blockage of veinous return from the retina, mainly from increased ICP
Protein coagulation in the lens of the eye
Cataracts
Age-related increase in intraocular pressure
Glaucoma
1 cause of blindness
Glaucoma
S/S of this include painless, slow loss of peripheral vision
Open angle glaucoma
“Acute glaucoma”
Closed angle glaucoma
Severe, irreversible loss of central vision due to destruction of a central part of the eye
Macular degeneration
Risk factors for Macular degeneration include
HTN
Smoking
Caucasian race
Diabetes
S/S of Macular Degeneration
clear peripheral vision with black spots in central vision
Posturing (decerebrate/decorticate) in a stroke victim is caused by
brain stem involvement
Breathing pattern change seen in brain stem stroke PTs
Cheyne Stokes breathing
Cerebellar strokes may present with problems including
balance, vertigo, incoordination
Mydriasis occurs in response to:
the SNS releasing Norepinephrine
Externally visible S/S of a diffuse stroke
bilaterally weaker sensation, muscle tone, movement, strength, and reflexes
Pressure required to get oxygenated blood to perfuse the cells of the brain
Cerebral perfusion pressure
Possible S/S of Alzheimer’s
Dementia
behavioral changes
emotional upset
possible motor/gait changes
Unequal pupils cann indicate
neuro disorder such as increased ICP or intracranial hemorrhage
Damage to CN III will cause what?
Abnormal pupil dilation due to loss or diminishing of pupillary constriction abilities
What rules sensorimotor status below the shoulders?
Corticospinal and spinothalmic tracts
What rules sensorimotor status above the shoulders?
12 cranial nerves
Typical S/S of a cerebellar stroke
Problems with coordination & balance
Pathological changes of a focal lesion of the motor tracts will be
unilateral & contralateral
Crossing over of nerve fibbers from the motor tracts
decussation
Acute state of confusion due to problems such as high fever, electrolyte imbalances, etc.
delirium
