Nervous System Flashcards
What is the somatic nervous system responsible for controlling in the body?
Voluntary movement
What is the autonomic nervous system responsible for controlling in the body?
Involuntary processes and organ function
Which cranial nerve innervates the diaphragm?
The phrenic nerve
Which cranial nerve is implicated during the type of syncope brought on when someone’s trying too hard to get a poop out?
The vagus nerve (vasovagal syncope)
Which acronym can be used to describe reasons for altered LOC?
AEIOUTRIPS
A: Acidosis, Abuse of Substances, Arrhythmias
E: Environmental, Epilepsy, Encephalopathy, Electrolytes, Endocrine
I: Infection
O: Overdose
U: Underdose, Uremia
T: Trauma, Tumour
R: Respiratory (not always part of this list)
I: Insulin
P: Poisoning, Psychogenic
S: Shock, Stroke, Seizure, Syncopy
What are the 5 phases of a grand mal (tonic-clonic) seizure?
- Aura
- Tonic
- Hypertonic
- Clonic
- Postictal
What is a petit mal (absence) seizure? Describe.
A brief loss of consciousness without any associated motor activity. Usually lasts less than 15 seconds.
What do afferent neurons do?
They are sensory neurons which carry information from the PNS to the CNS.
What do efferent neurons do?
They are motor neurons which carry impulses from the CNS to the effector organs.
What do interneurons do?
They are association neurons which exist in the CNS and link the afferent and efferent neurons.
What is a grand mal (tonic-clonic) seizure? Describe.
A stereotypical seizure which is characterized by 5 phases. Involves loss of consciousness, muscle rigidity, convulsions, and a confused post-seizure period.
What is a simple focal seizure? Describe.
Characterized by clonic activity to a specific body area. Usually resulting from overstimulation/damage to a particular part of the brain.
What is a complex focal seizure? Describe.
Like a simple focal seizure in that activity is limited to one part of the body/brain. Additionally, can present with ALOC, memory loss, changes in behaviour, or repetitive behaviour.
What is a pseudoseizure? Describe.
A condition which mimics a true seizure but usually originates from a psychological disorder. Does not have a postictal phase and can sometimes be deliberately interrupted.
You are called to a patient who has been experiencing a seizure. At what point might you consider them to be in status epilepticus rather than a normal seizure?
If their seizure lasts more than 5 minutes or if they do not return to consciousness between 2 or more generalized seizures. (request ACP!)
If a patient is experiencing status epilepticus, why is it important to call ACPs without delay?
They can give benzodiazepines to treat this condition. This may be the only effective pre-hospital treatment available to us.
What patient population is most at risk for a febrile seizure? What causes these?
Usually seen in children between 6 months and 3 years old (can occur up to 6 years though). Brought on by a sudden spike in core temp >40C.
Give at least 3 examples of mechanisms which could cause syncopy.
Any of:
- Vasovagal reaction
- Torsades de pointes
- Transient asystole
- Ventricular tachycardia
- Bradycardia (any type)
- Cardiomyopathy
- Drugs or medications
- Dehydration
- Hypoglycemia
- Pulmonary embolism
+ Many more (even idiopathic)
What is nystagmus? (kind of a tough one, sorry)
A rhythmic up and down, side to side, or circular motion of the eyes occurring with syncopy.
What is delirium? What usually causes this? (note: “Delirium” and “Excited Delirium” present differently and have different pathologies).
Delirium presents as abrupt disorientation and may be accompanied by hallucinations. It is mostly brought on by severe illness causing brain dysfunction.
What differentiates delirium and dementia? How can we figure out which one a patient is experiencing? (note: “Delirium” and “Excited Delirium” present differently and have different pathologies).
Delirium is a new-onset condition while dementia is usually a progressive and chronic illness that this patient has been experiencing for some time. A good history from a witness is the best way to differentiate in the pre-hospital setting.
True or False: Alzheimer’s Disease and Dementia are synonymous terms and can be used interchangeably.
False. Alzheimer’s Disease is a TYPE of Dementia (general term for cognitive decline) caused by neurodegeneration. Other causes of dementia exist.
What is Bell’s Palsy? What other neurological condition can it sometimes be mistaken for?
Bell’s Palsy is an inflammation of the 7th cranial nerve. It causes facial muscle paralysis and can present with the same one-sided drooping facial expression that can be seen during a stroke.
What acronym is used to identify whether someone is having a stroke? What acronym is used to assess stroke severity?
FAST (Face, Arms, Speech, Time) and VAN (Vision, Aphasia, Neglect)
A patient is presenting with left-sided weakness that started about 3 hours ago. They have no other injuries but their heart rate seems elevated. What life-threatening condition might they be experiencing?
Even though they don’t have any facial droop or speech abnormalities, they could still be experiencing a stroke. The increased HR could be compensatory for the blockage in their brain.
A patient called 9-1-1 due to a “sudden awful headache” and when you arrive they have vomited and are seizing. What condition are they likely experiencing?
A hemorrhagic stroke can present this way. Rapid transport is imperative.
Describe the symptoms which characterize Cushing’s reflex. What causes this?
Hypertension, Bradycardia, and diminished respiratory effort. Caused by increased ICP.
