brain part 2 Flashcards

1
Q

within how many hours can IV recombinant tPA be given after a patient exhibits sx of an acute ischemic CVA

A

within 4.5 hours of sx onset

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

risk factors for CVA include (6)

A

HTN (most important)
smoking
DM
HLD
ETOH excessive
elevated homocysteine level

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

usual first therapy for patients who suffered an ischemic (not hemorrhagic) CVA

A

PO așa

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

eligible CVA patients with large vessel occlusion should receive embolectomy within how many hours of sx onset

A

6

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

target BP for ischemic CVA patient

A

under 185/110

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

fluid, temp, BG anesthetic considerations for CVA patient

A

fluid supports CO, BP, CPP, and improves BF by decreasing blood viscosity
monitor BG’s, tx high BG with insulin. glucose is converted to lactic acid in severe ischemia and is associated with bad outcomes
-controlled hypothermia can reduce CMRO2

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

management considerations for cerebral vasospasm following SAH include

A

reducing HCT to 30
niMOdipine
daily trans cranial doppler exams
triple H therapy (HTN, hemodilution, hypervolemia)

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

most common cause of subarachnoid bleeding

A

aneurysm rupture in circle of willis

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

what increases risk of aneurysm rupture

A

HTN(?) or an acute reduction in ICP. basically ICP creates a tamponade effect.

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

surgical options for hemorrhagic CVA

A

aneurysm clipping or endovascular coiling
-to minimize risk of re bleeding, surgical repair should take place within 24-48h following initial bleed

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

if you heparinize for the endovascular coil to be placed and the aneurysm ruptures during this time, you should

A

reverse the heparin, lower map to low/normal range, can give adenosine to help surgeon stop bleeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

intraop BP control for hemorrhagic CVA
also considerations for open repair where surgeon is clamping

A

SBP should be between 120-150mmHg
-if patient undergoes an open repair, clamp is placed on proximal feeder vessel. this reduces transmural pressure and decreases the risk of aneurysm rupture so you won’t need controlled HoTN but you will need a normal/high BP to perfuse collateral circulation.
too high and no clamp- rupture could occur
too low- auto regulation is impaired and could not be perfusing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

when cerebral vasospasms most commonly occur
how to monitor for them
presentation
dx
tx

A

most commonly occur 4-9 days following SAH
frequent neuro checks and daily transcranial doppler exams
most common presentation is new neurologic deficit or altered LOC
dx: cerebral angiography is gold standard
tx: aimed at maintaining CPP (increase MAP 20-30mmHg above baseline), if vasospasm occurs, triple H therapy (hypervolemia, HTN, hemodilution to 27-32%), nimodipine, balloon angioplasty

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

a medically refractory vasospasm can be treated with what before balloon angioplasty?

A

intra arterial vasodilators, CCB’s like verapamil or nicardipine. can also try papaverine and milrinone

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

define cerebral salt wasting syndrome

A

patients who suffer SAH are at risk for this
most common cause of hyponatremia in this population. brain releases natriuretic peptide which causes contraction, hyponatremia, and sodium washing by the kidney.
CSW is tx with isotonic crystalloids

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

distinction between CSW and SIADH

A

CSW is tx with isotonic crystalloids while SIADH is tx with fluid restriction since its associated with slight hypervolemia

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

if you have a minor head injury and satisfy these requirements, you do not need a CT

A

no physical evidence of trauma above the clavicles
no HA
no n/v
no neurologic deficit
no impairment of short term memory
no intoxication
no seizures
age <60y

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

review GCS and which number is associated with TBI

A

<8, TBI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

ways to reverse wafarin (3)

A

FFP, prothrombin complex concentrate, recombinant factor 7a

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

ways to reverse clopidogrel and/or ASA

A

platelet transfusion,

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

anesthetic management of TBI, keep CPP

A

> 70mmHg

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

two things to specifically avoid in a patent with TBI

A

prolonged hyperventilation can worsen cerebral ischemia in patents with TBI
steroids can worsen neurologic outcomes

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

albumin and TBI

A

linked to poor outcomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

nitrous oxide and TBI

A

PTX can be lurking, you dont know. just dont touch it with TBI victim

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

jacksonian march

A

a partial seizure that progresses to a generalized seizure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

tonic phase versus clonic phase

A

tonic: whole body rigidity. TONE
clonic: repetitive jerking motions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

grand mal seizure key points/distinctions
acute tx
surgical tx

A

generalized tonic/clonic activity
respiratory arrest due to hypoxia an increased O2 consumption due to increased brain activity
acute tx: propofol, diltiazem, thiopental
surgical tx: vagal nerve stimulator or resection of foci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

focal cortical sz sx

A

localized to particular cortical region
can be motor or sensory
usually no LOC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

absence (petit mal) sz sx

A

temporary loss of awareness (but remains awake)
more common in children

30
Q

akinetic sz sx

A

temporary LOC and postural tone, which can result in fall and head injury
more common in children

31
Q

status epilepticus sz sx
acute tx (6)

A

sz activity that lasts >30 min or
2 grand mal seizures without regaining consciousness in between
respiratory arrest due to hypoxia and increased O2 consumption due to increased brain activity

acute tx: phenobarbital, thiopental, phenytoin, benzos, prop, GA

32
Q

anesthetic agents and seizures
EEG activity
sx of sz under GA

A

all have been implicated in inducing sz activity
reduce EEG in dose dependent fasion
sx of sz under GA: tachycardia, HTN, increased EtCO2 and O2 consumption

33
Q

etomidate and EEG

A

while it is associated with myoclonus, it is not associated with increased EEG activity in patients who do not have epilepsy

34
Q

in patients with sz DO’s, which drugs can induce sz activity and help ID location of seizure foci during cortical mapping

A

methohexital, etomidate, alfentanil

35
Q

LA’s and seizure threshold

A

reduce seizure threshold but properly placed regional anesthetic has no effect on this

36
Q

drugs that have metabolites capable of inducing sz activity

A

atracurium produces laudanosine which can induce seizures but you’d only see this with long term infusion use in ICU
cis makes less of this and therefore its not really a thing
normeperidine (metabolite of meperidine) is capable of producing seizure activity

37
Q

drug used as anti convulsant that is excreted unchanged by the kidneys

A

gaba

38
Q

Phenytoin MOA/comments

A
39
Q

valproic acid MOA/comments

A
40
Q

carbamazepine MOA/comments

A
41
Q

gabapentinoids MOA/comments

A
42
Q

DOA of which drug would be prolonged in an Alzheimer’s patient who takes donepezil

A

succ, mivacurium, ester type LA’s because cholinesterase inhibitors are the main stay for alzheimers tx

43
Q

alzheimers s/sx (4)

A

memory loss
apraxia
aphasia
agnosia

44
Q

alzheimers pathophysiology and dysfunctions related to it

A

diffuse beta amyloid rich plaques and neurofibrillatory tangles in the brain

dysfx r/t plaque formation:
dysfunctional synaptic transmission (most common in Ach neurons)
apoptosis (programmed cell death)

45
Q

alzheimers tx

A

cholinesterase inhibitors to restore Ach including donepezil, tacrine, rivastigmine, galantamine

46
Q

anesthetic management of/considerations for alzheimer’s patients

A

short acting drugs under GA is best because the idea is to allow them to return to baseline cognition faster.
avoid preop sedation as it can worsen confusion
probs won’t cooperate for a MAC
cholinesterase inhibitors can increase parasympathetic tone so bradycardia/syncope/n/v can develop
if an anticholinergic is required, glyco is best since it doesn’t cross BBB

47
Q

pathophysiology of Parkinson’s disease

A

dopaminergic neurons in basal ganglia are destroyed which favors an increase in cholinergic activity.
increased Ach activity in basal ganglia increases GABA activity in thalamus. since GABA is inhibitory, increased GABA suppresses thalamus.
thalamic inhibition suppresses cortical motor system and motor areas in brain stem. final result is over reactivity of EPS.

48
Q

dx of Parkinson’s disease

A

you have 2 of the 4 cardinal signs
1. resting “pill roll” tremor
2. skeletal muscle rigidity
3. postural instability, loss of balance with an altered gait
4. bradykinesia- very slow movement and reflexes

-secondary signs include psychosis, depression, dementia, lack of facial expression, diaphragmatic spasm, oculogyric crisis.

49
Q

Parkinsons tx: levadopa and carbidopa

A

levodopa and carbidopa- levodopa is precursor to dopamine. carbidopa is a decarboxylase inhibitor. by preventing levodopa metabolism in blood, more levodopa can enter CNS.
SE: increased inotropy, tachycardia, orthostatic HoTN, dyskinesia, n/v

levodopa has half life of 6-12 hours so make sure they take it morning of surgery!

50
Q

Parkinsons tx: selegeline

A

MAO-B inhibitors restore dopa concentration by reducing metabolism in CNS
(unlike non selective MAOI’s, selegeline does not increase the risk of tyramine induced hypertensive crisis)

51
Q

other tx’s for parkinsons include

A

dopamine agonists
anticholinergics
COMT inhibitors
amantadine
hormone replacement

52
Q

anesthetic considerations for a patient with parkinsons disease

A

at risk for autonomic instability, orthostatic HoTN, dysrhythmias, aspiration.
antidopaminergic drugs such as metoclopramide and butyrphenones (haldol and droperidol) and phenothiazines (promethazine) may exacerbate EPS. these drugs are contraindicated
HoTN should be tx with intravascular volume expansion and direct acting agents like neo
monitor for postop ventilatory failure

53
Q

alfentanil and the parkinson patient

A

may cause dystonic reaction due to interruption of central dopaminergic transmission

54
Q

drug useful for sedation and reduction of tremors in the parkinson patient

A

diphenhydramine

55
Q

DBS and levadopa

A

holding levodopa causes sx to worsen which can help facilitate optimal electrode placement

56
Q

how is DBS performed (parkinson patient)

A

-requires a burr hole to insert electrodes into sub thalamic nucleus, globus pallidus, ventralis intermedius. done under stereotactic guidance.
-patients head is placed in a rigid frame
-to determine optimal electrode placement, patient has to be awake but can be lightly sedated with opioids/precedex
-patient is in sitting position which increases risk of VAE. can monitor with precordial doppler. if it occurs, tell patient NOT to take deep breath, tell patient to flood field
-to minimize ICH risk, SBP <140
-sz’s can be tx with small dose of prop, barbs, benzos

57
Q

GABA and DBS

A

because of the crucial role of gaba in the thalamus, drugs that inhibit GABA (prop or benzos) are avoided as they can interfere with electrophysiologic brain monitoring

58
Q

corneal abrasion
s/sx
dx
prevention
tx

A

s/sx: pain, foreign body sensation, photophobia, excessive tearing, conjunctival erythema, diminished visual activity. blindness is rare
dx: fluorescein stain. when examined with cobalt blue slit light or pen lamb, abrasion will appear green
prevention: tape horizontal, goggles
tx: abx drops for 24h, topical or PO NSAIDS, self limiting and resolves in 1-3d
patching is not recommended because it does not improve pain and can delay healing

59
Q

most common cause of postop visual loss

A

ION

60
Q

most likely explanation of ION

A

inadequacy of blood supply to optic nerve (CN2) due to venous congestion in optic canal, reducing ocular perfusion pressure.
increased intra abdominal or intra thoracic pressure can also increase IOP

61
Q

ocular perfusion pressure =

A

MAP-intraocular pressure

62
Q

when does vision loss from ION commonly occur

A

24-48h post surgery

63
Q

anesthesia and patient risk factors for ION

A
64
Q

difference between how ION and central retinal artery occlusion start

A

ION starts as nerve problem where CRAO starts as vascular problem

65
Q

pathophys and sx of CRAO

A

occlusion of retinal artery (ex reduced venous out flow due to improper head position)
sx: sudden painless vision loss in one eye upon waking up from anesthesia

66
Q

risk factors for CRAO

A

using a horseshoe in the prone position (better options include foam face pillow)
-embolism (most common after CPB)
-administering N2O after retinal detachment surgery with intraocular gas bubble

67
Q

which anticonvulsants create resistance to non depolarizers?

A

phenytoin, carbamazepine

68
Q

which anticonvulsant follows zero order kinetics

A

phenytoin

69
Q

the DOA of which NMB will be increased if used on an alzheimer’s patient who takes donepezil

A

succ since mainstay tx for alzheimers is cholinesterase inhibitors

70
Q

drugs you should not give to parkinson patients include

A

antidopaminergic drugs such as metoclopramide and butyrphenones (haldol and droperidol)
phenothiazines (promethazine)
alfentanil (can cause acute dystonic reaction due to interruption of dopa)

71
Q

what do you use to tx parkinson sx exacerbation

A

anticholinergics (since theres too much Ach and not enough dopa)

72
Q

MOA of selegeline

A

MAO-B inhibitor that reduces dopa metabolism to help restore balance of dopa