Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PNP > PNP WK7 > Flashcards

PNP WK7 Flashcards

Nervous system disorders

1
Q

What is the definition of an intercranial cause to loss of consciousness?

A

Related to the direct impact on anatomical structures of or within the cranium
- Head injury, hemorrhage etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the definition of an extracranial cause to loss of consciousness?

A

related to secondary causes from issues outside the cranium
- Hypoxia, hypo/erglycaemia-tension.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a persistent coma?

A
  • unconsciousness
  • no sleep/wake cycle
  • focal damage at brain stem/thalamus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is locked-in syndrome?

A
  • brain stem injury that affects transmission of motor function
  • awareness of surroundings but cannot respond to stimuli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a vegetative state?

A
  • Follows sleep/wake cycles
  • Roused by stimuli but cannot show awareness of surroundings
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the criteria for brain death?

A
  • Cessation of brain function
  • Absence of brain stem responses
  • Absence of spontaneous respirations
  • Irreversible brain damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is intercranial pressure?

A
  • the forces exerted within the cranium and thus the brain
  • is determined by vol of brain tissue, cerebrospinal fluid and intravascular blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is cerebral perfusion pressure?

A
  • The pressure of blood flow (o2) to brain tissue
  • CPP= Mean Arterial Pressure (blood entering cranium)- Intercranial Pressure (blood leaving cranium)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the Monro-Kellie doctrine?

A

the components exist in volume equilibrium, so an increase in any of the 3 cerebral components will increase ICP and must be compensated for by decreasing the overall volume of the other two cerebral components

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the early steps the body takes to deal with an increased ICP?

A
  • shifts CSF to spinal cavity to increase venous return from brain (briefly effective)
  • Resulting hypoxia triggers arterial vasodilation to improve CPP to brain (briefly effective and adds fluid in brain)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If ICP increases, what is done to critically supply the brain with O2?

A
  1. Cerebral ischemia
  2. Systemic vasoconstriction to force blood into brain
  3. Baroreceptors cause bradycardia
  4. Chemoreceptors respond to low CO2 levels and decrease resp. rate
    CUSHING REFLEX (widened bp, bradycardia and irregular resps)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the result of damage to the upper motor neurons (corticospinal tract)?

A
  • Weakness/paralysis to opposite side of body (due to crossover at medulla oblongata)
  • Muscle tone/reflexes increased due to no inhibitors sent to site
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the result of damage to the lower motor neurons (corticospinal tract)?

A
  • Weakness/paralysis to same side of body
  • Muscles are flaccid and reflexes reduced
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the difference between decorticate and decerebrate (two involuntary motor responses from brain damage)?

A

Decorticate: rigid flexion in the upper limbs, lower limbs extended, caused by severe damage in cerebral hemispheres
Decerebrate: upper and lower limbs are extended, body is arched, caused by CNS depression or brain stem legions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are local/focal effects?

A
  • signs related to the specific area of damage to the brain or spinal cord
  • e.g. paralysis of right arm from damage to left side of frontal lobe
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens the vision if the
- Optic chiasm
- Optic nerve
- Optic tract
is disrupted?

A

Chiasm: Field of vision in both eyes is disrupted
Nerve: Field of vision in eye on same side is disrupted
Tract: info on the lateral same side, and medial other side will be damaged

17
Q

What is the difference between expressive, receptive and global aphasia?

A

Expressive: Cannot speak or write fluently
Receptive: Unable to understand language
Global: Cannot express self or comprehend others’ language

18
Q

What is the definition of a seizure?

A

an episode of inappropriate neuronal electrical discharge resulting in disordered brain activity in the cerebral cortex

19
Q

What is a TIA (transient ischemic attack)?

A
  • Temporary localised reduction in blood flow to the brain
  • Caused by partial occlusion, embolus, spasm
20
Q

What is a Cerebrovascular accident (CVA)?

A
  • A stroke, sudden lack of blood supply to certain parts of the brain due to plaque build up in artery that breaks off
  • Ischemic: sudden blockage to cerebral artery causing necrosis as a result of a thrombus (clot) or embolism (moving clot)
  • Haemorrhagic: cerebral artery ruptures and there is a brain bleed, loss of blood supply and increased ICP, can be caused by hypertension
21
Q

What is a cerebral aneurism?

A
  • localized dilation in an artery from a rupture in the artery wall
  • blood, along with CSF causes an inflammatory response, vasospasm and increased ICP
22
Q

What is the pathophysiology of a malignant primary brain tumour?

A
  • no well-defined margins, are invasive, have a layer of inflammation surround adding to the pressure
  • increasing mass can lead to herniation
  • don’t normally metastasize out of the CNS
23
Q

What are the different types of partial seizures?

A
  • Simple Partial: Only one hemisphere involved, no LOC
  • Complex Partial: Temporal lobe, consciousness is impaired, automatism and post-ictal present
24
Q

What are the types of generalised seizures?

A

Absence : lapse in consciousness for 10 seconds
Atonic: sudden loss of muscle tone
Myoclonic: sudden uncontrolled jerking of 1+ limbs
Tonic-clonic: immediate LOC, tonic phase involves muscle contraction and body stiffening, clonic phase involves flexion spasm then muscular relaxation

25
Q

What are the pharmacological agents that we can use against seizures?

A

Phenytoin: removal of sodium ions during the refractory period of the action potential, stabilises cortical nerves against hyper-excitability and prevents discharging neurons from repeated firing

Benzodiazepines: inhibits firing of hyperexcitable neurons, enhances action of the inhibitory transmitter GABA

Phenobarbitone: depress neuronal excitability by enhancing chloride ion influx at GABA receptors

26
Q

What is the difference between coup and contre coup injuries?

A

Coup: injury directly below the point of impact
Contre coup: injury on the opposite side due to the brain hitting the other side of the skull from rebound

27
Q

What are the features of an epidural haematoma?

A
  • Bleed between the dura and skull
  • Involves arteries
  • Tearing of middle meningeal artery in temporal region
  • Increased ICP
28
Q

What are the features of an subdural haematoma?

A
  • Bleed between dura and arachnoid membrane
  • Involves bridging veins
  • Tear/rupture in vein causes slow bleed, possible leak into subdural space increasing ICP
29
Q

What are the features of an subarachnoid haematoma?

A
  • Between arachnoid and pia mater
  • Tangling between veins and arteries causes tear and bleed into space
  • Aneurism **
  • Arterial blood
30
Q

What is the difference between a diffused axonal and focal injury?

A

Diffused axonal injury: Widespread, caused by shaking motion which causes strains in brain and interruption of brain function
Focal: Focused, due to tears in blood vessels and causes haematomas

31
Q

What would happen post spinal impact?

A
  • inflammation and oedema occurs, spinal cord no longer viable and spinal shock occurs, no reflexes
  • Eventually only residual effects present
32
Q

What is autonomic dysreflexia?

A
  • abnormal overreaction of ANS to stimuli
  • Noxious stimuli travels up spinal cord by stops at site of injury (T6)
  • SNS is activated, vasoconstrict and BP inc.
  • Body tries to counteract with dec. HR, headache, sweat
  • PNS takes over top half, SNS takes over bottom half
33
Q

What are different damages to the cervical spine?

A

Hyperflexion: result from forceful deceleration
Vertical compression: vertebral column is compressed
Hyperextension: whiplash
Extension-rotation: lateral extension/ extreme twist of neck

34
Q

What are incomplete spinal cord injuries (syndrome)?

A

Central cord: injury to centre of cervical spinal cord
Anterior cord: damage to motor and sensory pathway in anterior part of spine
Brown-Sequard: injury that has occurred to either left or right side of spine
Cauda Equina: affects lumbosacral nerve roots, caused by herniation

PNP (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions