Brainscape's Knowledge GenomeTM

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


See full index

6901 > Neurosurgery > Flashcards

Neurosurgery Flashcards

1
Q

unmyelinated neurons appear _____ and conduct _____ signals at a _____ speed; myelinated neurons appear _____ and conduct _____ signals at a _____ speed;

A

grey, action potential, slower

white, saltatory conduction, faster

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

saltatory conduction

A

action potential that moves in jumps on myelinated neurons at the nodes of Ranvier

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

astrocytes

A
  • provide support to neurons

- blood brain barrier

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

ependymal

A

-CSF production

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

microglia

A

-phagocytosis within the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

oligodendrocytes

A

-provide the myelin sheath in the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Schwann cells

A

-provide the myelin sheath outside the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

inhibitory neurotransmitter

A

GABA - opens Cl channels which hyperpolarizes the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

excitatory neurotransmitter

A

glutamate - opens Na channels which hypopolarizes the cell

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

gyri

A

-outer 3 mm of cerebral cortex that is convoluted to increase surface area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

brainstem (3 components)

A
  • midbrain (RAS - consciousness, arousal, alertness)
  • pons
  • medulla (respiratory and cardiovascular control)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

meninges spaces and layers (out to in)

A
  • epidural
  • dura (tough)
  • subdural space
  • arachnoid (web-like, BBB, avascular)
  • subarachnoid (CSF)
  • pia (soft)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

mnemonics for cranial nerve - sensory versus motor

A

some say money matters, but my brother says big brains matter more

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

CNS vasculature

A
  • anterior = carotid artery
  • posterior = vertebral artery

*meet at Circle of Willis

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

cerebral blood flow rate and percentage of CO

A
  • 50mL/100g/min of brain tissue

- 15-20% of CO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

cerebral perfusion pressure (CPP)

A

CPP = MAP - ICP (or CVP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

neurology = ATP stores are depleted and cellular injury can occur within _____

A

3-8 minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

CBF relationship with CMRO2

A

CBF is directly influenced by cerebral metabolic rate of oxygen (CMRO2) which parallels
glucose consumption

  • 20% of body’s O2 consumption
  • 3-3.8mL/100g/min
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

CBF relationship with CPP

A

CBF remains constant with CPP between 50-150 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

CBF - PaCO2 and PaO2 effects

A

PaCO2 - increased produces vasoconstriction, decreased produces vasodilation, controls between 20-80 mmHg, 3% for each 1 mmHg **most important regulator

PaO2 - little effect until below 50 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

CBF relationship with ICP

A

CBF decreases when ICP >30 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

CBF relationship with temperature

A

CBF decreases 5-7%

with 1 degree Celsius decrease of temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Cerebral Spinal Fluid

A
  • produced in choroid plexus in ventricles at 30 mL/hr; reabsorbed in arachnoid villi
  • total volume = 150 mL
  • CSF pressure 5-15 mmHg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

intracranial components

A
  • brain matter=80%
  • blood=12%
  • CSF=8%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

normal ICP

A

5-15 mmHg

26
Q

Cushing Reflex

A
  • HTN, bradycardia, respiratory irregularities

- occurs in response to acute increased ICP

27
Q

types of brain herniation

A
  • uncal
  • central: transtentorial
  • cingulate
  • transcalvarial: moves out hole in skull
  • upward: cerebellar
  • tonsillar: cerebellar down
28
Q

how does edema appear on a CT of the brain

A

hypodensity

29
Q

what is the gold standard for ICP monitoring

A

intraventricular catheter

**also allows for drainage

30
Q

neurology: volatile anesthetics autoregulation

A

-autoregulation (coupling) is impaired in concentrations exceeding 1 MAC (uncoupling=CMR the same, CBF increased)

31
Q

Robin Hood Phenomenon

A

only normal tissue can vasoconstrict, ischemic brain tissue cannot constrict

32
Q

neurology: volatile anesthetics CMR

A

-decreased with all, nitrous may increase

33
Q

neurology: volatile anesthetics CBF

A

-increased with all

34
Q

neurology: volatile anesthetics CBV

A

-increased with iso

35
Q

neurology: volatile anesthetics ICP

A

-increased with all

36
Q

neurology: Propofol

A

-dose dependent decrease in CBF and CMROs

37
Q

neurology: etomidate

A

-decrease in CMRO2, CBF, ICP

38
Q

neurology: ketamine

A
  • dilates cerebral vasculature

- increases CBF, ICP, CBV

39
Q

neurology: opioids

A

-minimal effect

40
Q

neurology: benzodiazepines

A
  • decrease CBF and CMR to a lesser extent than barbiturates

- interfere with electrocorticography

41
Q

neurology: precedex

A

-decrease in CBF WITHOUT decrease in CMRO2 = can produce ischemia

42
Q

neurology: succinylcholine

A
  • increase ICP, CBF, CMRO2
  • usually not avoided if rapid paralysis is needed
  • avoid after 48 hours from stroke or spinal cord injury due to up-regulation of acetylcholine receptor causes hyperkalemia
43
Q

neurology: muscle relaxants

A
  • no effect on ICP, CBF, CMRO2
  • histamine (atracurium) produces vasodilation which increases ICP
  • interaction with other anti-seizure medications: increased dose with decreased duration of action due hepatic enzyme induction
44
Q

neurology: labetalol and esmolol

A

-no effect

**preferred for the control of HTN

45
Q

neurology: nipride, nitroglycerin, hydralazine

A
  • dilates cerebral vessels

- increases CBV, ICP

46
Q

neurology: steroids

A
  • reduce edema

- most common decadron

47
Q

neurology: diuretics

A
  • loop: general diuresis, decrease CSF production, decrease cerebral edema
  • osmotic: decrease intra and extra cellular water: Mannitol – slow administration (fast produces vasodilation, rise in CBF, ICP, CBV), 0.25-1.0 g/kg over 10-15 min
48
Q

neurology: diuretics

A
  • loop: general diuresis, decrease CSF production, decrease cerebral edema
  • osmotic: decrease intra and extra cellular water: Mannitol – slow administration (fast produces vasodilation, rise in CBF, ICP, CBV), 0.25-1.0 g/kg over 10-15 min
49
Q

neurology: fluid goal

A
  • euvolemia

- avoid dextrose-containing fluids

50
Q

neurology: target blood sugar

A

140-180

51
Q

venous air embolism versus paradoxic air embolism

A
  • venous=stays within right ride of heart

- paradoxic=enters arterial circulation through patent foramen ovale

52
Q

venous air embolism signs

A
  • increase in expired nitrogen, EtCO2

- decrease in SaO2

53
Q

most sensitive monitor to detect venous air embolism

A

transesophageal echocardiography

54
Q

pituitary neoplasms

A
  • rarely metastatic
  • neurologic, hormonal, visual changes
  • common for loss of ADH: treat with DDAVP 0.5-1 ug
55
Q

classification for cerebral aneurysms

A

Hunt & Hess: 0-5

0=unruptured aneurysm
5=deep coma, decerebrate rigidity

56
Q

subarachnoid hemorrhage risks

A
  • cardiac dysfunction
  • neurogenic or cardiogenic pulmonary edema
  • hydrocephalus
  • rebleeding: 50% chance
  • vasospasm
57
Q

aneurysm clipping

A
  • removes the risk of recurrent hemorrhage

- should not be postponed

58
Q

neurology: vasospasm

A
  • occurs 4-9 days after in 1:4
  • leading cause of m/m
  • treatment: hypertension, hypervolemia, hemodilution,
  • nimodipine or nicardipine decrease incidence
59
Q

aneurysms: endovascular treatment

A
  • coil in aneurysm clots blood
  • avoid hyperventilation which causes vasoconstriction makes access difficult
  • heparin/protamine
60
Q

carotid artery stenting concerns

A

-bradycardia or asystole with angioplasty - do not pretreat with atropine

6901 (18 decks)

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