UNIT 10 NERVOUS SYSTEM DYSFUNCTION

Question 1

Intracranial pressure (ICP)

Answer 1

an increase in volume of brain tissue, CSF or blood

Question 2

ICP signs ans symptoms

Answer 2

headache
nausea
confusion
seizures
coma
increased BP
loss of pupillary reflex

Question 3

Causes of ICP

Answer 3

brain swelling
tumors
hydrocephalus

Question 4

Brain swelling

Answer 4

1. vasogenic = extracellular fluid increase

2. cyctotoxic = intracellular fluid increase (infection leading to inflammation)

Question 5

Hydrocephalus

Answer 5

CSF increases in volume of ventricles
swelling of pons and cerebellum
may not always increase ICP -> brain tissue volume decreases and replaced by CSF (Alzheimer’s)

Question 6

consequences of ICP

Answer 6

• brain compression
• compartment syndrome (cut off of blood flow)
• brain herniation = pushed brain out of position (causes blurred/double vision)

Question 7

How does the body compensate for ICP

Answer 7

• CSF shunt to spinal cord
• hyperventilation -> vasoconstriction (limits free radicals)
• induced coma decreases metabolism and decreases injury

Question 8

Evaluation of brain injury

Answer 8

• neurological exam and ABC
• CT scan
• monitor for increased ICP (headache etc)

Question 9

Primary TBI

Answer 9

• concussion

- contusion

Question 10

Contusion definition

Answer 10

injury that doesn’t disrupt skin integrity usually caused by blows to head or violent movement of skull
-loss of integrity of blood vessels

Question 11

characteristics of contusion

Answer 11

• swelling
• discoloration
• pain

Question 12

contusion classifications

Answer 12

• focal contusion

- polar contusion = coup and countercoup

Question 13

Concussion definition

Answer 13

functional loss due to damaged axons

Question 14

characteristics of concussion

Answer 14

• microscopic damage
• axonal injury
• loss of memory
• it is usually temporary

Question 15

concussion classifications

Answer 15

grade 1 = transient confusion, no loss of consciousness, symptoms resolve in less than 15min
grade 2= transient confusion, no loss of consciousness, symptoms resolve in more than 15min
grade 3= any loss of consiousness

Question 16

Secondary TBI causes

Answer 16

• ischemia
• hemorrhage
• infection
• increased ICP

Question 17

Hematoma/hemorrhage

Answer 17

1. Epidural hematoma
2. subdural hematoma
3. subarachnoid hemorrhage
4. intracerebral hemorrhage

Question 18

Epidural hematoma

Answer 18

• rapid bleeding
• between dura and the skull
• results in coma

Question 19

Subdural hematoma

Answer 19

• slow bleeding
• between dura and arachnoid matter
• caused by blunt trauma
• non-specific symptoms caused by increased ICP

Question 20

Subarachnoid hemorrhage

Answer 20

• between arachnoid and pia layer
• caused by traumatic contusion of brain or rupture of berry aneurysms
• high mortality

Question 21

Intracerebral hemorrhage

Answer 21

• complication of head trauma
• leads to rupture of intracerebral vessels
• non-traumatic forms also occur (leukemia, stroke)

Question 22

Atherosclerosis

Answer 22

vessel occlusion

• wall of artery weakens and stretches, increasing risk of rupture and hemorrhage
• increased risk of clot formation

Question 23

Strokes

Answer 23

• Ischemic
• Hemorrhage
• transient ischemic attack (TIA)
• acute stroke

Question 24

Ischemic strokes

Answer 24

• 88% of strokes are ischemic
  1. Thrombotic (80%) = atherosclerosis with thrombus formation
  2. embolic (20%) = caused by Afib, valvular disease
  - leads to cerebral infarcts -> global aphasia (broca and wernicke area affected), Receptive aphasia (wernicke affected), Expressive aphasia (broca affected)

Question 25

Hemorrhagic stroke

Answer 25

- 15% - caused by structural abnormalities - aneurysms form (in circle of willis berry aneurysms)

Question 26

TIA

Answer 26

- mini stroke - resolve quickly - no permanent loss of function

Question 27

Acute stroke

Answer 27

- focal neurological signs | - depends on where damage is

Question 28

CNS infections

Answer 28

Meningitis: | - headache, stiff neck, fever, changes in level of consciousness, CSF high in protein and WBC and low in glucose

Question 29

Brain tumors

Answer 29

- high mortality rate - malignant tumors of the brain do not metastasize - 50% of brain tumors are metastases from: lung cancer, breast cancer or melanoma

Question 30

clinical manifestations of brain tumors

Answer 30

1. focal disturbances - dysfunction of certain areas - seizures, hallucinations, weakness, sensory deficits 2. generalized disturbances - increased ICP

Question 31

Seizures

Answer 31

erratic firing of cortical neurons | - provoked by electrolyte imbalance, hypoglycemia, CNS infection or damage

Question 32

Epileptic syndromes

Answer 32

Partial seizures | Generalized seizures

Question 33

Partial seizures

Answer 33

- can tell ahead of time - begin in one hemisphere and can spread to the other side 1st stage = Aura 2nd stage = Ictus 3rd stage = post-ictus

Question 34

Generalized seizures

Answer 34

- both hemispheres | - consciousness is lost at onset

Question 35

functional forms of seizures

Answer 35

ABSENCE = disturbance in consciousness ATONIC = loss of muscle tone MYOCLONIC = long muscle contractions TONIC-CLONIC = shorter muscle contractions and loss of consciousness GENERALIZED CONVULSIVE = continue without recovery between seizures

Question 36

Alzheimers Disease characteristics

Answer 36

- dementia - cerebral atrophy - neurofibrillary tangles - amyloid plaques - decreased Ach production

Question 37

Alzheimer stages

Answer 37

1. short term memory loss 2. confusion 3. incontinence, cant recognize family/friends