Neuro Flashcards
Where does all our conscious voluntary movement start?
In the frontal lobe motor cortex.
What makes up grey matter?
Dendrites and cell bodies and end feet
What makes up white matter?
Axons covered in mylein sheath
THE NEUROTRANSMITTER IN THE SKELETAL MUSCLE IS?
Acetylcholine
What receptors does acetylcholine fit into?
The two receptors it fits in is the nicotinic receptor and muscarinic receptor (this only in reference to the PNS system, not the voluntary receptor)
Which enzyme destroys acetylcholine?
Acetylcholinesterase (AChE)
What are the longest cells in our body?
The upper motor neurons
If the upper motor neuron is damaged, will we still have a reflex on the other side of the body?
Yes, because only the lower motor neuron is involved in reflexes.
What causes a floppy/flaccid paralysis?
When the lower motor neuron is affected by disease or something; no reflex
What causes a spastic paralysis?
When the upper motor neuron is affected by disease or something; reflex still present
What is fasciculation?
a brief spontaneous contraction affecting a small number of muscle fibres, often causing a flicker of movement under the skin.
What is an autoimmune disease?
When the body is making antibodies, but instead of making them against pathogens; you are making them against yourself.
Upper motor neuron disease originates where?
The brain
Lower motor neuron disease originates where?
Spinal cord
What is definition of multiple sclerosis?
Definition: scattered demyelination of CNS neurons, scaring, causing faulty impulse conduction (sclerosis means hardening) It is a chronic disease. It is an upper motor neuron disease. (CNS- BRAIN and Spine)
Guillain- Barre syndrome description:
Acute peripheral polyneuritis (P’NS)
This is a lower motor neuron disease because of the word PERIPHERAL.
This one is symmetrical and ascending (starts in the feet and goes upwards)
It starts suddenly and will get better.
It is still an autoimmune disease, it can start after the flu, the lymphocytes did not cease making antibodies for the flu and will now attack yourself.
Bilateral ptosis =
Droopy eyelids
What cranial nerves are involved in swallowing?
The glossopharengeal (#9), hypoglossal (#12) and the vagus (#10) nerves
What cranial nerves are involved in speech?
Hypoglossal (#12), vagus (#10), glossopharengeal (#9), and the facial (#7) nerves
What is myasthenia Gravis?
Myasthenia gravis is a chronic autoimmune neuromuscular disease characterized by varying degrees of weakness of the skeletal (voluntary) muscles of the body. The name myasthenia gravis, which is Latin and Greek in origin, literally means “grave muscle weakness.”Myasthenia gravis is caused by a defect in the transmission of nerve impulses to muscles. It occurs when normal communication between the nerve and muscle is interrupted at the neuromuscular junction—the place where nerve cells connect with the muscles they control. Normally when impulses travel down the nerve, the nerve endings release a neurotransmitter substance called acetylcholine. Acetylcholine travels from the neuromuscular junction and binds to acetylcholine receptors which are activated and generate a muscle contraction.
In myasthenia gravis, antibodies block, alter, or destroy the receptors for acetylcholine at the neuromuscular junction, which prevents the muscle contraction from occurring. These antibodies are produced by the body’s own immune system. Myasthenia gravis is an autoimmune disease because the immune system—which normally protects the body from foreign organisms—mistakenly attacks itself.
The problem lies at the neuromuscular junction, the muscle receptors are not picking up the acetylcholine.
Amyotropic Lateral Sclerosis (AKA Lou Gehrigs Disease)
Voluntary neuromuscular disease. Motor neurons are nerve cells located in the brain, brain stem, and spinal cord that serve as controlling units and vital communication links between the nervous system and the voluntary muscles of the body. Messages from motor neurons in the brain (called upper motor neurons) are transmitted to motor neurons in the spinal cord (called lower motor neurons) and from them to particular muscles. In ALS, both the upper motor neurons and the lower motor neurons degenerate or die, and stop sending messages to muscles. Unable to function, the muscles gradually weaken, waste away (atrophy), and have very fine twitches (called fasciculations). Eventually, the ability of the brain to start and control voluntary movement is lost.
Upper (cortex) and lower (ant. horn) motor neuron disease, muscle weakness
Starts hands and feet, swallowing
Wide spread, rapidly progressive
? cause, more men, age 40 and over
No treatment
What is involved in the nursing neurological assessment?
Preliminary survey and vital signs Mental state Sensory symptoms Motor symptoms Reflexes Cranial nerves
What are some of the diagnostics that can be done?
Clinical picture, history
Reflexes, balance, sensation
CSF analysis
MRI or CAT scan
EMG
Blood tests
Nursing interventions for neuro disease?
Promote activity Provide comfort Prevent complications – infection, constipation Promote adequate nutrition Promote communication
What is the treatment for neuromuscular disease?
No effective cure Manage signs + symptoms Cortisone Symptomatic Immunosuppressive drugs Plasmaphoresis Rehabilitation
What is plasmaphoresis?
a method of removing blood plasma from the body by withdrawing blood, separating it into plasma and cells, and transfusing the cells back into the bloodstream. It is performed especially to remove antibodies in treating autoimmune conditions.
What could cause more brain tissue than normal?
- Encephalitis- inflammation in the brain, causing heaps more interstitial fluid and leaky capillaries.
- Tumor
- Abscesses
What can cause more blood in the brain?
- Hemorrhage
- CVA
When would we get more CSF in our head?
-Meningitis
-
Where does the CSF flow?
From the third ventricle down to the fourth ventricle
Where is CSF fluid made?
The corroid plexus in the third ventricle makes CSF fluid.
A tumor in the corroid plexus can overproduce the CSF.
Differences between epidural, subdural and intracerebral hematoma:
Epidural- outside the dura
Subdural- A subdural hematoma (SDH) is a collection of blood below the inner layer of the dura but external to the brain and arachnoid membrane
Intracerebral- Intracerebral hemorrhage occurs when a diseased blood vessel within the brain bursts, allowing blood to leak inside the brain.
What is the Blood brain barrier?
a semipermeable membrane separating the blood from the cerebrospinal fluid, and constituting a barrier to the passage of cells, particles, and large molecules. that is extra protection against pathogens and drugs in the circulation from getting into the brain etc
What do neurons need to stay alive?
Blood, oxygen and glucose
What stops blood, oxygen and glucose from getting into the neurons?
Increased intercranial pressure
Head injuries are synonymous with..
Raised intercranial pressure
What could be relevant in the blood that could help with the diagnosis of a traumatic head injury?
Potassium- to ensure impulse conduction remains normal
Glucose- to ensure brain has enough levels to function
We do this as baseline, these aren’t huge indicators!
What is papilledema?
Papilledema (or papilloedema) is optic disc swelling that is caused by increased intracranial pressure.
What is in CSF?
Glucose
Fluid
Protein
Why would a pt with head injury being nausea?
Pressure on the vomiting centre; in the medulla.
Projectile vomiting = increasing pressure on medulla.
What can an urinalysis tell us about increased intercranial pressure?
In the hypothalamus, ADH is made and secreted though the posterior pituitary gland; if the brain injury presses on the hypothalamus, it wont make any ADH. If this isn’t made, your urine output will be hugely increased.
What is a normal urine output per hr?
300mls
What are the principles of management for brain injuy?
Treat cause Stop further elevation of ICP Monitor patient Supply adequate substrate for metabolism Prevent or minimize complications Physical and emotional support Raise slightly for pressure to decrease
What is the dorsal column for?
General sensation
Spinothalamic tract is for?
The pain tract
The spinal cord is always what?
Bilateral- two of everything, one on each side
In the sensory pathway where do its paths cross?
crosses in the medulla, comes up on the same side though all the way into the medulla.
Where does the pain pathway (spinothalamic) cross?
in the motor root of the spinal nerves.
I.E. you MUST test for sensation AND pain in ALL the limbs.
Where does the pain pathway (spinothalamic) cross?
in the motor root of the spinal nerves.
I.E. you MUST test for sensation AND pain in ALL the limbs.
Motor neurons are travel on what pathway?
The descending pathway
Monoplegia
paralysis restricted to one limb or region of the body.
Hemiplegia
paralysis of one side of the body
Quadraplegia
All 4 limbs paralysed
Tetraplegia =
All 4 limbs paralysed
Lpsilateral=
same side of the injury is where the paralysis is
Paraplegia =
Paraplegia is an impairment in motor or sensory function of the lower extremities.
Contralateral =
Opposite side damage and effect
What does the GCS do?
GCS – defines consciousness in 3 modes of behaviour
Eye opening
Verbal response
Motor response
Highest score 15/15 fully altert patient
Lowest possible score 3/15 totally comatose patient
A score of 8 or less is generally indicative of a coma
AVPU =
Alert
Responds to verbal
Responds to painful stimulus
Completely unresponsive
Other than GSC and AVPU, what additional assessments can the nurse make?
- Vital signs
- Pupil size & reaction to light
- Limb movement – arms & legs
What 2 cranial nerves does the light reflex test?
CSF opening pressure: 50–180 mmH2O.
Glucose: 40–85 mg/dL.
Protein (total): 15–45 mg/dL.
What is the Monro-Kellie hypothesis?
States that due to limited space within the
skull, an increase in any one of the components
requires a change in one of both of the others.
Brain tissue limited capacity to change
Compensation is achieved by:
Displacing CSF
Decreasing Cerebral Blood Flow (CBF)
What does the cranial vault contain?
- Brain
- Blood
- CSF
What is the normal ICP?
Normal ICP 0-20mmHg
Increased ICP is prolonged pressure above >25mmHg
What is the nursing management of increased ICP?
als:
Maintain a patent airway
Have an ICP within ‘normal’ limits
Demonstrate normal fluid and electrolyte balance
No complications secondary to immobility and
decreased level of consciousness
What is papilodemia?
Swelling of the optic disk
What is Cushing’s response?
Set of three things that happen with increased ICP
- Increased BP
- Dcreased HR
- Irregular breathing
Increased ICP causes:
Coneing- pushing the swollen brain through the brain stem and causing hernia.
What is brain herniation?
Brain herniation is a potentially deadly side
effect of very high intracranial pressure that
occurs when a part of the brain is squeezed
across structures within the skull.
There are two major classes of herniation:
supratentorial - is of structures normally above the
tentorial notch
infratentorial - is of structures normally below it
What does increased ICP do to respirations?
In general, an initial increase in intracranial
pressure causes respirations to slow; as the
pressure continues to increase, respirations
become rapid
How high should the bed of the head be raised for a patient with a brain injury?
No higher than 45 degress
