What anatomical structures make up the central nervous system?
Brain and spinal cord
What anatomical structures make up the peripheral nervous system?
Spinal nerves/peripheral nerves
The CNS is responsible for ___.
thought, perception, feeling, and autonomic body functions.
The peripheral nervous system transmits ____.
commands from the brain to the body and receives feedback from the body.
Largest part of the brain.
What is the role of the cerebrum?
Front part controls emotion and though.
Middle part controls sensation and movement.
Back part processes sight.
Right and left hemispheres of the cerebrum controls the opposite side of the body.
Where in the brain is speech controlled?
Left side of the brain near the middle of the cerebrum.
The brainstem controls basic functions, such as:
What is the cerebellum responsible for?
Coordinating complex tasks that involve voluntary movement of muscles.
projection from the cell body that extends towards another cell carrying signals from the neuron.
Role of myelin sheath.
Increased speed of conduction and insulates the neuron to allow the cell to transmit its signal efficiently and consistently.
Function of the occipital lobe.
vision and storage of visual memories
Function of the parietal lobe.
Sense of touch and texture; storage of tactile memories.
Function of temporal lobe.
Hearing and smell
Storage of sound and odor memories
Function of frontal lobe.
Motor cortex: voluntary muscle control and storage of spatial memories.
Prefrontal cortex: judgement and prediction of consequences of a person’s actions; abstract intellectual functions.
Function of hypothalamus.
Interface w/ endocrine system
Function of midbrain.
Level of consciousness.
Reticular activating system which controls arousal and consciousness.
Muscle tone and posture.
Function of pons.
Respiratory pattern and depth.
Function of medulla oblongota.
Function of cranial nerves.
Special peripheral nerves that connect directly from the brain to body parts to relay information from the brain.
Function of peripheral nerves.
Brain to spinal cord to body part.
Receive stimulus from body.
Sends commands to body.
Two basic types of stroke:
hemorrhagic - arterial rupture
ischemic - embolism or thrombus
Interruption of cerebral blood low may results from:
Dead brain cells due to lack of oxygen.
Cells have enough oxygen to stay alive, but not enough to function properly.
Severity of hemorrhagic CVA depends on ___ and ____.
location; size of ruptured cerebral vessel
Which patients are at a higher risk of hemorrhagic CVA?
Chronic, poorly controlled HTN
Aneurysms occur in the following ways:
- A small tear or defect occurs w/in wall of artery.
- Blood penetrates b/n layers of artery.
- Pressure build up causing a small tear.
TIA are often signs of:
Serious vascular condition that requires medical evaluation.
General s/s of CVA.
Facial drooping Sudden weakness or numbness Decreased or absent movement and sensation of one side of the body. Ataxia or loss of balance. Sudden vision loss, blurry vision or double vision. Dysphagia. Decrease LOC Aphasia Dysarthria Sudden and severe HA Confusion Dizziness Combativeness Restlessness Tongue deviation Coma
Expressive : difficulty expressing thoughts or inability to use the right words.
Receptive : difficulty understanding spoken words.
S/S left hemispheric CVA.
Right sided deficit and aphasia.
S/S right hemispheric CVA.
Left sided deficit, dysarthria, and visual disturbances.
Why do s/s of epidural hematoma develop rapid vs. slowly with subdural hematoma?
Epidural hematomas are usually caused by arteries where as subdural hematomas are usually veins.
What are the two classifications of seicures?
Generalized - affecting large portions of the brain.
Partial - affecting limited area of the brain.
Steps in tonic-clonic seizures.
Aura Loss of consciousness Tonic phase Hypertonic phase Clonic phase Post seizure Postictal phase
Describe the tonic and hypertonic phase of a seizure.
Tonic : body-wide rigidity
Hypertonic : arched back and rigidity
Describe clonic phase of a seizure.
Rhythmic contractions of major muscle groups, lip smacking, biting, and teeth clenching.
When should you ventilate a patient having an active seizure.
Apneic for more than 30 seconds.
What is the difference between a seizure and a pseudoseizure?
Root cause of usually psychiatric in origin.
Presence w/ little or no movement. Typically occur in children. No postictal period or confusion. Can be caused by flashing lights or hyperventilation.
Involves only a limited portion of the brain.
Simple partial seizure.
Movement of one part of the body or altered sensations.
Complex partial seizures.
Subtle changes in LOC; may experience hallucinations, inability to speak; small movement of head or eyes.
Seizure that lasts longer than 4-5 minutes or consecutive seizures that occur w/o return of consciousness between episodes.
Why is status epilepticus life-threatening?
Neurons use large amounts of glucose and produce lactic acid - hypermetabolic state. No long-term damage during a short period. Long period can cause damage or death to neurons.
List epileptic medications:
Phenytoin (Dilantin) Phenobarbital Carbamazepine (Tegretol) Levetiracetam (Keppra) Gabapentin (Gabarone, Neurontin) Lamotrigine (Lamictal)
Focus (generalozed or focal)
Activity (type of movements)
Color or Cocaine (cyanosis or indication of cocaine use)
Time (length of seizure)
Secondary information (medications, events leading up to seizure, incontinence, tongue biting)
Common causes of seizures
Abscess Alcohol Birth anomaly Brain infections Brain trauma DM Fever Eclampsia Idiopathic Inappropriate medication dosage Organic brain syndrome Recreational drug use Stroke or TIA Systemic infection Tumor Uremia
Why does breathing become labored in a postictal state?
The body is attempting to compensate for the buildup of acids.
Consider hypoglycemia in a patient who:
Had a seizure w/ hx of DM
AMS after MVC
Potential causes of syncope:
Cardiac rhythm or conduction Cardiac muscle MI Dehydration Hypoglycemia Vasovagal episode
POssible cuases: stress, altered cortisol levels, depression
s/s : residual muscle contractions w/in face and head causing stiffness. May experience stiffness in jaw, neck, or shoulder.
Type of pain: dull, squeezing
Causes: minor instability w/ certain cluster of neurons and changes in blood vessel size at the base of the brain.
s/s : unilateral pain, aura, photophobia, n/v
Type of pain: throbbing, pounding, pulsating
Rare vascular headaches occurring in groups and last 30-45 minutes. Minor pain around eye.
Type of pain : sharp and excruciating
A : alcohol, acidosis E: epilepsy, endocrine, electrolytes I : insulin O : opiates U : uremia T : trauma, temperature I : infection P : poisoning, psychogenic S : shock, stroke, syncope, space-occupying lesion, subarachnoid hemorrhage
Arms adducted and flexed against chest
Legs internally rotated
Feet turned inward
Head and neck arched
Arms straight and hands curled
Toes pointed downwards
Decorticate and decerebrate posturing are signs of?
Decorticate posturing indicates damage to the area directly below _____
Decerebrate posturing is a sign of damage within or near ____.
“Cat’s eyes and cat’s cries.”
Increased ICP in an infant will cause them to shriek similar to a cat. Shape of the pupils can become more oval.
Sign of increased ICP: BP increases HR decreases RR irregular Systolic hypertension widens
Cincinnati Prehospital Stroke Scale
LA Prehospital Stroke Screen
- Age > 45 years
- Hx of seizures or epilepsy absent
- Symptoms < 24 hours
- At baseline, does not use a w/c or is not bedridden
- BGS 60-400
- Asymmetry in: facial smile/grimace, grip, and arm strength
How would the pupils react to bleeding in the brain or ICP?
Pupil sizes will change. As pressure increase, pupil on the injured side of the brain becomes larger or fully dilated