The Nervous System Flashcards
function of the occipital lobe
vision
function of the parietal lobe
perception, math, spelling, logic
function of temporal lobe
memory, language
Frontal Lobe
thinking, planning, organizing, problem-solving, emotions, behavioural control, personality.
function of the cerebellum
balance
Broca’s area function
expressive language
Wrenicke’s Area function
language, understanding spoken language.
components of the peripheral nervous system
cranial nerves, spinal nerves, and peripheral nerves.
function of the CSF
protects the brain and spinal cord from injury
provides nourishment to the brain
normal ICP of CSF is 5-15mmHg
Monroe-Kellie Hypothesis
The skull is riigid container filled with blood, brain, and CSF; if one increases, the other increases.
Causes of increased ICP
tumours, bleeding, hydranencephaly, and edema
Signs and Symptoms of increased ICP
headache; vomiting; changes in consciousness and orientation; drowsiness; thirst; decreased GCS; hypertonic; decerebrate; decorticate; hypotonic; flaccid; deceased reflexes; pupillary changes; nystagmus; papilledema; change in speech; shivering; confusion
Decorticate Positioning
damage to the mid-brain; flexion of arms towards the spinal cord; clenching fist; rigid muscles.
Decerebrate Positioning
damage to the deep brain and Pons. Involves extension of arms with flexion of the wrists and clenched fists; legs straight; rigid; head and neck arched back.
Functions of the Sympathetic Nervous System
- dilates pupils
- inhibits salvation
- increases HR
- dilates bronchi
- inhibits peristalsis
- glucose release
- adrenaline and noradrenaline release
- inhibits bladder
Functions of the Parasympathetic Nervous System
- constricts pupils
- stimulates salivation
- decreases HR
- constricts bronchi
- stimulates peristalsis
- bile release
- stimulates intestines
- constricts the bladder
Cranial nerve 1
Olfactory - sense of smell
Cranial nerve II
Optic - vision
Cranial nerve III
Oculomotor - eye movement
Cranial nerve IV
Trochlear - hearing
Cranial nerve V
Trigeminal - mastoid control; chewing
Cranial Nerve VI
Abducens - extra-ocular motor function of the eye
Cranial nerve VII
Facial (face and tongue control)
Cranial Nerve VIII
Vestibulocochlear - hearing and balance
Cranial IX
Glossopharyngeal – motor, parasympathetic, and sensory information from nose, mouth, and throat; enables swallowing.
Cranial Nerve X
vagus nerve – swallowing and speaking
Cranial Nerve XI
accessory nerve – supplies sternocleidomastoid and trapezius muscles
Cranial Nerve XII
hypoglossal – efferent nerve for tongue musculature.
Midazolam
Pharm. Class: Benzodiazepine; Anti-Anxiety Agent
Indications: anxiety
Onset: Rapid
Duration: 1-2 hrs
Alprazolam
Pharm. Class: Benzodiazepine
Indication: Anxiety
Onset: Intermediate
Duration: 6-12 hrs
Clonazepam
Pharm. Class: Benzodiazepine
Onset: Intermediate
Duration: 18-50 hrs
Lorazepam
Pharm. Class: Benzodiazepines
Indication: Anxiety; seizure
Onset: Intermediate
Duration: 2-6 hrs
Diazepam
Pharm. Class: Long-Acting Benzodiazepine
Indication: anxiety; MHSU
Duration: 20-50hrs
Phenytoin (Dilantin)
Pharm. Class: Anticonvulsant
Action: treats seizures; provides prophylaxis through blocking sustained high-frequency repetitive firing action potentials in the brain.
Therapeutic Level: 10-20mg/L
Considerations: May cause gingival hyperplasia; antacids can reduce effects on the body.
Acetaminophen
Pharm Class: NSAID; #1 fever control
Therapeutic Indication: antipyretic; non-opioid analgesia
Action: inhibits the synthesis of prostaglandins which leads to decrease in transmission of pain signals and fever response.
Considerations: 4g max daily dose; long-term 3g per day recommended; monitor liver function
Antidote: Acetylcysteine.
ASA
Pharm. Class: antipyretic; non-opioid analgesic
Indication: pain, arthritis, stroke, MI prophylaxis
Action: inhibits the production of prostaglandins which decreases ischemic symptoms of heart disease.
Considerations: Risk of bleeding (D/C within 5 days of surgery); caution with paediatric patients; may cause peptic ulcers; give with food.
Morphine
Pharm. Class: CNS depressant; opioid analgesia
Action: binds to opioid receptors in the brain to alter perception of pain while producing CNS depression.
Considerations: constipation; CNS depression; monitor HR, RR
Antidote: Naloxone.
Other Opioids: fentanyl, hydromorphone, morphine, oxycodone, oxycontin.
Signs and Symptoms of Basilar Skull Fracture
- battle sign
- raccoon eyes
- cerebrospinal rhinnorhea
- torn/non-torn dura
Battle Sign
Bruising over the mastoid process
Why wouldn’t you insert an NG tube on a patient with a basilar skull fracture?
you could insert the NG tube directly into the brain
Halo Test
testing rhinnorhea for presence of CSF halo around droplet on paper. Additionally, the presence of glucose would indicate CSF fluid.
Epidural Hematoma
dura pulled off the skull; rapid expansion of arterial blood between duramatter and skull.
Subdural Hematoma
dura attached; slow expansion of venous blood between arachnoid and dura.
Hydrocephalus
accumulation of CSF causes increase in ICP
Causes: tumour; hemorrhage; infection; congenital
Treatment:
- VP shunt (tube inserted to redirect csf to the urinary tract)
- External Ventricular Drain (drains CSF directly)
Optimal CSF pressure
5-15mmHg