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N935 Advanced Pathophysiology > Neuromuscular Diseases > Flashcards

Neuromuscular Diseases Flashcards

1
Q

What is a neuromuscular disease?

A

disorder that adversely affects muscle function, either primarily or via nerve or NMJ abnormalities

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2
Q

What is an upper motor neuron?

A

motor pathway completely contained within the CNS.

Begins in the cerebral cortex and ends in the ventral horn of the spinal cord.

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3
Q

Where does an upper motor neuron begin?

A

cerebral cortex

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4
Q

Where does an upper motor neuron end?

A

ventral horn of the spinal cord

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5
Q

What are the primary roles of upper motor neurons?

A

Directing, influencing, & modifying:

  • reflex arcs
  • lower-level control centers
  • motor neurons

some sensory

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6
Q

Where do upper motor neurons [generally] form synapses?

A

with interneurons

[which form synapses with lower motor neurons before projecting to the periphery

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7
Q

What does the corticospinal tract supply?

A

the voluntary muscles of the trunk & extremities

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8
Q

Where does the corticospinal tract begin?

A

precentral gyrus

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9
Q

What 3 structures does the corticospinal tract go through?

A
  1. internal capsule
  2. midbrain
  3. pons
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10
Q

What are the 2 structures formed from the beginning of the corticospinal tract?

A
  1. lateral corticospinal tract

2. ventral corticospinal tract

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11
Q

What is the lateral corticospinal tract?

A

75-90%
tract that crosses (decussates) in the medulla;
at each level some fibers leave the tract & enter the ventral horn grey matter to form synapses with lower motor neurons

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12
Q

What is the ventral corticospinal tract?

A

10-25%
tract that does NOT cross (decussate) in the medulla;

Fibers make a SMALL cross over before synapsing with lower motor neurons

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13
Q

What is the corticobulbar tract?

A

follows the corticospinal tract until the brainstem, then innervates the cranial nerves (motor) [CN 3, 4, 6, 9, 10, 11 bilaterally]
[CN 7, 12 unilaterally- this is why strokes have facial droop or tongue “droop]
- CN 7 innervates the “upper” face bilaterally, the “lower” face unilaterally = mouth droop”)

supplies the voluntary muscles of the head & is involved in precise motor movements

originates in the precentral gyrus, next to the lateral fissure of Sylvius

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14
Q

What CN does the corticobulbar tract innervate?

A

cranial nerves (motor) [CN 3, 4, 6, 9, 10, 11 bilaterally]

cranial nerves 7, 12 unilaterally- this is why strokes have facial droop or tongue “droop”]
- CN 7 innervates the “upper” face bilaterally, the “lower” face unilaterally = mouth droop)

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15
Q

Where does the corticobulbar tract originate?

A

precentral gyrus, next to the lateral fissure of Sylvius

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16
Q

Where are lower motor neurons located?

A

in the brainstem or spinal cord

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17
Q

What are lower motor neurons responsible for?

A

direct influence on muscles

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18
Q

Where do axons of the lower motor neurons go?

A

through nerves in the PNS to synapse on and control skeletal muscle cells

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19
Q

What do lower motor neurons that PASS THROUGH THE SPINAL NERVES control [primarily]?

A

muscles of the limbs and the trunk

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20
Q

What do lower motor neurons that PASS THROUGH CRANIAL NERVES control [primarily]?

A

skeletal muscles of the head & neck

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21
Q

What does damage to lower motor neurons lead to?

A

paralysis [unless nerve re-generation occurs]

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22
Q

What breaks down acetylcholine in the synaptic cleft?

A

the enzyme acetylcholinesterase

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23
Q

What happens to the components of acetylcholine after it is broken down?

A

taken back up into the presynaptic cell for resynthesis

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24
Q

What is recycled in the NMJ after an AP?

A

acetylcholine & vesicles

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25
Q

What are the effects of an upper motor neuron lesion?

A

UMN (pyramidal cells) Motor Cortex

  • muscle groups are affected
  • mild weakness
  • minimal disuse muscle atrophy
  • no fasciculations
  • increased muscle stretch reflex
  • hypertonia
  • spasticity
  • pathological reflexes
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26
Q

What type of muscles are affected in an upper motor neuron lesion?

A

muscle groups

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27
Q

What kind of atrophy is seen in upper motor neuron lesions?

A

minimal disuse atrophy

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28
Q

Is the muscle stretch reflex increased or decreased in upper motor neuron lesions?

A

increased

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29
Q

Are muscles spastic or flaccid in upper motor neuron lesions?

A

spastic

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30
Q

What are the affects of a lower motor neuron / ventral horn / motor nuclei lesion?

A
  • individual muscles are affected
  • mild weakness
  • marked muscle atrophy
  • fasciculations
  • decreased muscle stretch reflex
  • hypotonia, faccidity
  • NO babinski sign
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31
Q

What are 5 upper motor neuron diseases?

A
  1. cerebral palsy
  2. multiple sclerosis
  3. cerebrovascular accident
  4. Parkinson’s
  5. Huntington’s
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32
Q

What is cerebral palsy?

A

non-progressive disorder caused by injury or abnormal development in the immature brain;

before, during, or after birth, up to 1 year of age.

**damage to the CORTICOSPINAL PATHWAY

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33
Q

What are neurological s/s of CP?

A

intellectual disabilities
psychiatric conditions
seizures
vision/hearing/speaking impairment

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34
Q

What are musculoskeletal s/s of CP?

A 
problems with swallowing
difficulty speaking
exaggerated reflexes/spasticity
stiff muscles
lack of coordination
slow movement
scissors like gait
muscle weakness
scoliosis/contractures/joint dislocation
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35
Q

What is a GI problem associated with CP?

A

GERD

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36
Q

In CP do patients have any up or down regulation of receptors? If so, what receptor?

A

yes, up-regulation of nAChR

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37
Q

What are 5 types/categories of surgery commonly seen in CP?

A 
ortho
dental
general
optho
ENT
  • dorsal rhizotomy
  • Nissen
  • intrathecal baclofen pumps
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38
Q

What is one medication commonly used to relieve some of the s/s of CP?

A

botulinum toxin

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39
Q

What are () anesthetic considerations of CP?

A
  1. hold/caution with pre-op sedatives/opioids (use short acting & small doses)
  2. decreased dose of volatile anesthetics (↓MAC by 20-30%) & NDMR [sux does not cause increased K]
    • USE BIS & NM MONITORING!
  3. difficult airway & risk of aspiration
    • RSI
    • dentition, secretions, TMJ ankylosis, contractures
  4. difficult vascular access
  5. high risk of latex allergy
  6. prone to bleeding, hypothermia, intravascular depletion
  7. SLOW EMERGENCE
  8. do they take seizure medications?
    • how are liver labs?
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40
Q

What effect does succinylcholine have in patients with CP?

A

does NOT produce elevated K!!

  • but patients have an upregulation of nAChR??
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41
Q

Can succinylcholine be given in patients with CP?

A

YES! [will not cause an increase in K] but avoid if you can or use a ↓ dose!

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42
Q

What type of problem is multiple sclerosis?

A
  • upper motor neuron disorder
  • autoimmune disease
  • conduction problem
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43
Q

What is multiple sclerosis?

A

autoimmune dz characterized by a combination of DEMYELINATION, INFLAMMATION, & AXONAL DAMAGE of the CNS.

**peripheral nerves are NOT affected

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44
Q

What are 7 s/s of multiple sclerosis?

A
  1. paresthesia (face, arms, fingers, legs)
  2. muscle fatigue/weakness
  3. painful muscle spasms
  4. visual problems (optic neuritis & diplopia)
  5. autonomic instability
  6. bulbar muscle dysfunction
  7. cognitive dysfunction (advanced MS)
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45
Q

What are the 2 visual problems that can occur in multiple sclerosis?

A

optic neuritis

diplopia

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46
Q

What are 6 drugs that can be used in the treatment of multiple sclerosis?

BONUS: 2 more drugs

A 
diazepam
dantrolene
baclofen
steroids
immunosuppressants
monoclonal antibodies

interferon B1a [anti-inflammatory]
glatiramer acetate [immunomodulator]

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47
Q

What are 5 situations that exacerbate s/s of MS?

A 
stress
increased body temp (↑1c = block APs)
infection
hyponatremia
surgery
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48
Q

What vital sign is specifically important in patients with MS?

A

temperature.

increase by 1c can block action potentials from transmitting

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49
Q

What are 3 medications to specifically AVOID in multiple sclerosis?

A
  1. succinylcholine
  2. scopolamine
  3. atropine

d/t denervation

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50
Q

Can neuromuscular blocking drugs be used in patients with multiple sclerosis?

A

yes, but..

do NOT use succinylcholine
and use
non-depolarizing muscle relaxants sparingly

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51
Q

What is an anesthetic consideration during a flare of multiple sclerosis?

A

cancel surgery if it is elective!!

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52
Q

Can patients with multiple sclerosis receive a spinal block?

A

?questionable…

can possibly cause LA toxicity

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53
Q

Are epidurals safe in patients with multiple sclerosis?

A

yes

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54
Q

What type of induction should patients with multiple sclerosis have? Why?

A

RSI d/t aspiration risk

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55
Q

Patients with multiple sclerosis are at higher risk of (3)

A
  1. aspiration
  2. DVT
  3. exaggerated hypotensive effects (d/t impaired autonomic response)
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56
Q

Are steroids OK in patients with multiple sclerosis?

A

yes! they might be taking them as part of their treatment, you may need to give stress dose steroids.

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57
Q

Why might a patient with multiple sclerosis have an exaggerated hypotensive effect?

A

impaired autonomic response (ie. during induction)

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58
Q

Anesthetic considerations of multiple sclerosis (6):

A
  1. avoid sux, scopolamine, atropine, spinal block
  2. use NDMR cautiously
  3. give stress dose steroids, epidurals are OK
  4. avoid surgery during “flare-up” (if possible)
  5. Increased risk of aspiration, DVT, exaggerated hypotensive effects
  6. increased PACU length of stay… make sure pt is fully reversed…. could be s/s of a flare?
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59
Q

What is a cerebrovascular accident?

A

stroke characterized by sudden neurologic deficits d/t ischemia (88%) or hemorrhage (12%)

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60
Q

What are s/s seen in anterior cerebral artery stroke?

A

contralateral leg weakness

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61
Q

What are s/s seen in middle cerebral artery stroke?

A

contralateral hemiparesis & hemisensory deficit (face & arm > leg)
aphasia
contralateral visual field defect

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62
Q

What are s/s seen in posterior cerebral artery stroke?

A

contralateral visual field defect & hemiparesis

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63
Q

What are s/s seen in a penetrating artery stroke?

A

contralateral hemiparesis

contralateral hemisensory deficit

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64
Q

What are s/s seen in a basilar artery stroke?

A

oculomotor deficits and/or ataxia (loss of coordination/balance)
crossed sensory and motor deficits

65
Q

What are s/s of vertebral artery stroke?

A

lower cranial nerve deficits and/or ataxia with crossed sensory deficits

66
Q

What is the first thing done/obtained in a patient with suspected stroke?

A

non-contrast CT scan

67
Q

What is the “new” stroke mneumonic?

A

Balance
Eyes

Face
Arm
Speech
Time

68
Q

In a stroke patient, what will their blood pressure be?

A

HYPERtensive

69
Q

What is the goal BP in a stroke patient?

A

SBP 140-180 / DBP <105 before intervention

SBP 120-140 after intervention

70
Q

What will hypotension cause in a stroke patient?

A

cerebral vascular vasospasm

71
Q

What are 3 treatments for cerebrovascular accident?

A
  1. asprin
  2. TPA (IV administration or direct infusion into clot)
    [only in ischemic strokes]
  3. surgery (crani/cerebellar resection) - mechanical clot removal
72
Q

In an ischemic stroke patient, when can heparin be re-dosed in the OR?

A

> 1 hour since administration of heparin

73
Q

What is the goal ACT in an ischemic stroke patient?

A

ACT 200-300

74
Q

What are anesthetic considerations of a cerebrovascular accident?

A
  1. Increased risk of
    • DVT
    • aspiration
    • hyperglycemia (keep normal)
  2. BP maintenance
  3. AVOID hyperglycemia, dehydration, hyperthermia, infection
  4. regional/MAC can give more stable BP & reduced incidence of stroke
  5. Pts may be on aspirin, -statin, anticoagulant/anti-platelet therapy
  6. succinylcholine OK if <24H since insult
  7. ASSESSMENT/HX for baseline before surgery
75
Q

What is the goal SaO2 and SpO2 in cerebrovascular accident patients?

A

SaO2 >90%

PaO2 >60mmHg

76
Q

What is Parkinson’s disease?

A

neurodegenerative disorder of unknown cause marked by a characteristic loss of dopaminergic fibers in the basal ganglia

77
Q

In Parkinson’s dz, where does the loss of dopaminergic neurons occur?

A

in the basal ganglia

78
Q

What does depletion of dopamine in the basal ganglia cause?

A

Parkinson’s dz;

diminished inhibition of neurons controlling the extrapyramidal motor system & unopposed stimulation by acetylcholine

79
Q

What are the s/s of Parkinson’s?

A
  • Skeletal muscle tremor (pill-rolling) - more prominent during rest and will disappear during voluntary movement
  • rigidity
  • akinesia
  • diaphragmatic spasms
  • dementia
  • depression
  • facial immobility (infrequent blinking & paucity of emotional expressions)
80
Q

During movement/walking what are some s/s of a patient with parkinson’s?
(from picture in notes)

A 
masked face
stooped posture
back rigidity
forward tilt of trunk
flexed elbows & wrists
reduced arm swing
hand tremor
slightly flexed hip and knees
tremors in the legs
shuffling, short stepped gait
81
Q

What are 7 classes of drugs that can be used to treat Parkinson’s?

A
  1. dopamine precursor (levodopa)
  2. peripheral dopa decarboxylase inhibitor (carbidopa)
  3. antiviral agent (amantadine)
  4. Monoamine Oxidase Inhibitors-MAOIs (selegiline & rasagiline)
  5. dopamine agonists (ropinirole, bromocriptine)
  6. acetylcholinesterase inhibitors (donezepil, tacrine)
  7. COMT inhibitors (entacapone)
82
Q

What lab should be checked if the patient is taking entacapone?

A

liver enzymes

83
Q

What is one cardio side effect of amantadine?

A

prolonged QT

84
Q

What are the anesthetic considerations of Parkinson’s?

A
  1. continue levodopa therapy
  2. hypotension & cardiac dysrhythmias
    - use droperidol or haldol to correct hypotension
  3. aspiration/airway risk
  4. risk of HTN
  5. prone to POST-EXTUBATION LARYNGOSPASM
  6. avoid benzos
  7. sevo? is agent of choice?
  8. NDMR are LESS effective if pt is on anticholinergic for dementia…. use sugammadex
85
Q

What kind of vasopressors should be used in patients with Parkinson’s?

A

direct acting

86
Q

How does chronic anticholinesterase use affect succinylcholine adminstration/dose?

A

chronic anticholinesterase use will prolong succinylcholine, patient will tend to be resistant

87
Q

What is Huntington’s disease?

A

degenerative disease of the CNS characterized by marked atrophy of the caudate nucleus and to a lesser degree the putamen and globus pallidus.

88
Q

What 3 structures/locations of the brain are affected by Huntington’s disease?

A
  1. caudate nucleus
  2. putamen
  3. globus pallidus
89
Q

What are s/s of Huntington’s disease?

A

progressive dementia
chorea (involuntary jerking or writing movements)
tremors
rigidity/contractures
depression, aggressive outbursts, mood swings
difficulty with speech and swallowing

90
Q

What is the overall goal/treatment of Huntington’s disease?

A

↓ dopamine; either antagonize or deplete it

91
Q

What is usually the 1st s/s of Huntington’s disease?

A

chorea

92
Q

What is the treatment of Huntington’s disease?

A
  1. treat the choreiform movements
  2. antidepressants
  3. physical, occupational, speech therapies
93
Q

Huntington’s disease patients will have low levels of what plasma enzyme?

A

plasma cholinesterase

94
Q

What will happen if Huntington’s disease is “over-treated”?

A

too much dopamine is blocked == will look like parkinson’s disease

95
Q

What are anesthetic considerations of Huntington’s disease?

A
  • aspiration risk
  • prolonged response to succinylcholine → do not give!
  • sensitive to NDMR
  • can get spinal; but placement might be difficult d/t uncontrolled movements
  • consider avoiding reglan & anticholinergics (avoid drugs that will cross the BBB)
    [give glyco instead of atropine]
  • autonomic dysfunction
  • difficult IV access
96
Q

What are 7 lower motor neuron diseases?

A
  1. myasthenia gravis
  2. lambert-eaton
  3. muscular dystrophy
  4. myotonic dystrophy
  5. mitochondrial disorder
  6. Guillain-Barre
  7. Spinal Muscular Atrophy
97
Q

What is myasthenia gravis?

A

lower motor neuron disease;

autoimmune destruction or inactivation of postsynaptic acetylcholine receptors

[IgG antibodies against the nicotinic acetylcholine receptor]

Leading to:

  • reduced number of receptors & degradation of their function
  • complement-mediated damage to the postsynaptic end plate
98
Q

What is commonly found with myasthenia gravis?

A

70% of patients have thymus hyperplasia

99
Q

What are the s/s of myasthenia gravis?

A

*unevenly distributed muscle weakness & fatigue of extremities and face

diplopia, ptosis
fluctuating fatigue & weakness that improves after rest
muscle weakness of mouth and throat
dyspnea with exertion
proximal muscle weakness
100
Q

What is the key anesthetic implication of myasthenia gravis?

A

*do a good pre-op exam

→ know what meds they are taking
→ keep pt in PACU longer? possibly an overnight stay

101
Q

What is the treatment of myasthenia gravis?

A

*we want to ↑ the ACh @ the NMJ

cholinesterase inhibitor (pyridostigmine)
corticosteroids
immunosuppressants / IVIG
plasmapheresis (remove antibodies)
thymectomy
102
Q

What are situations that exacerbate symptoms of myasthenia gravis?

A 
pregnancy
infection
electrolyte imbalance
surgical & psychological stress
aminoglycoside antibiotics
magnesium
verapamil
lithium
steroids
phenytoin
103
Q

What are 2 ways to optimize a patient with myasthenia gravis?

A
  1. PFTs

2. plasmapheresis

104
Q

What are the anesthetic implications of myasthenia gravis?

A
  • aspiration risk
  • SENSITIVE to NDMR, respiratory depressants
  • RESISTANT to succinylcholine (give 2mg/kg); duration of action lasts 5-10m longer
    * cholinesterase inhibitors will ↓ plasma cholinesterase
  • regional anesthesia preferred (AVOID higher than mid-thoracic, interscalene, or supraclavicular blocks); do not make diaphragm weak!
    * give amide LA NOT esters
105
Q

What diagnosis is Lambert-Eaton often seen with?

A

small cell carcinoma

106
Q

What is Lambert-Eaton?

A

antibodies to presynaptic voltage-gated calcium channels markedly reduce the release of acetylcholine at the motor end plate

107
Q

What are the s/s of Lambert-Eaton?

A

proximal limb weakness, worse in the morning & improves throughout the day.

respiratory & diaphragm muscles become weak

autonomic nervous system dysfunction

  • orthostatic hypotension [pts are very sensitive]
  • slowed gastric motility
  • urinary retention
  • dry mouth
  • impotenance
108
Q

What is the treatment for Lambert-Eaton?

A 
DAP
guanidine hydrochloride
corticosteroids
immunosuppressants
plasmapheresis
*want to get more Ca into the presynaptic axon
109
Q

What are anesthetic considerations of Lambert-Eaton?

A
  • sensitive to succinylcholine AND NDMR
    * *inadequate reversal with anticholinesterase
  • high risk of postop respiratory failure [keep pts in PACU]
110
Q

Treatment with ___ drugs is NOT effective in Lambert-Eaton.

A

anticholinesterase

111
Q

What is Duchenne’s muscular dystrophy?

A

absence of the protein dystrophin;

membrane stays “open” → Ca+ floods into cell → muscle fiber maintains contraction & becomes necrotic → muscle fiber develops into “shell” and fills with fat [fatty infiltration & enlargement of muscles]

112
Q

What is the function of dystrophin?

A

maintenance of cell membrane

113
Q

What type of genetic disorder is Duchenne’s muscular dystrophy? (dominant/recessive, X-linked or Y-linked)

A

X-linked recessive

114
Q

When does Duchenne’s muscular dystrophy usually present?

A

between 2y-5y of age; rarely live past 30y

115
Q

What are s/s of Duchenne’s muscular dystrophy?

A

“Gower sign”- symmetric, proximal muscle weakness that is manifested as a gait disturbance

  • kyphoscoliosis
  • respiratory muscle weakness
  • degeneration of cardiac muscles & impaired cardiac conduction
  • impaired GI hypo-motility
  • impaired airway reflex
  • cognitive impairment
  • pulmonary HTN
116
Q

What is Becker muscular dystrophy?

A

*partial loss of dystrophin; progresses more slowly

X-linked recessive

117
Q

What are the s/s of Becker muscular dystrophy?

A

same as Duchenne MD but usually present later in life and progress more slowly
- proximal muscle weakness

  • intellectual disability is less common
118
Q

Death of Becker muscular dystrophy is usually caused by:

A

respiratory complications

119
Q

Diagnosis of muscular dystrophy is by:

A
  1. genetic testing
  2. CPK levels
  3. muscle biopsy (rare)
120
Q

What is the treatment of muscular dystrophy?

A
  • steroids (helps delay progression by 2-3yrs)
  • biphosphates (↑ Ca level & bone mass)
  • mystatin inhibitors (promote muscle growth d/t dying muscle groups)
  • gene modification
  • surgery (for scoliosis)
  • physical therapy
  • protease inhibitors
  • stem cell infusions
121
Q

Anesthetic considerations for muscular dystrophy:

A

“MH”-like reactions; FULL cardiac workup needs to be done

  • AVOID pre-med with benzos & opioids, succinylcholine, inhalation agents
  • intraoperative positioning d/t kyphoscoliosis
  • sensitive to NDMR
  • local & regional anesthesia preferrable
  • aspiration risk
122
Q

Muscular dystrophy patients are at increased risk of:

A
  1. respiratory infections
  2. masseter spasms
  3. prolonged post-op ventilation
123
Q

What is myotonic dystrophy?

A

autosomal dominant; r/t thymoma

hereditary, degenerative dz of the skeletal muscle that results in dysfunctional calcium sequestration by the sarcoplasmic reticulum

  • Na and Cl channel dysfunction is implicated as well
  • prolonged contractions
124
Q

What are s/s of myotonic dystrophy? (8)

A
  • weakness of facial, thoracic, intercostal, diaphragm, sternocleidomastoid & distal limb muscles
  • inability to relax hand grip (myotonia)
  • cardiomyopathy, conduction defects (1st degree block)
  • dysphagia, slowed gastric emptying
  • endocrine dysfunction (insulin)
  • central sleep apnea
  • ptosis
  • TRIAD IN MALES:
    1. frontal balding
    2. cataracts
    3. testicular atrophy
125
Q

What kind of workup do patients with myotonic dystrophy need?

A

cardiac work up

126
Q

What do you need for pts with myotonic dystrophy?

A

*pacer pads in room

GOAL: we do not want to start a muscle contraction b/c it will not stop

127
Q

What is the treatment of myotonic dystrophy?

A
  • procainamide
  • phenytoin
  • mexiletine
  • baclofen
  • dantrolene
  • carbamazepine
  • cardiac pacemaker
128
Q

What can exacerbate myotonic dystrophy?

A

muscle contraction

  • shivering
  • pregnancy & retained placenta
129
Q

What are the anesthetic considerations of myotonic dystrophy?

A
  • AVOID succinylcholine,
  • aspiration risk
  • Volatile anesthetics can cause exaggerated myocardial depression, but high concentrations of VA can abolish myotonia
  • anesthesia & surgery can aggravate cardiac conduction by increasing vagal tone
  • Drugs that can AGGREVATE myotonia: propofol, neostigmine, physostigmine, methohexital, etomidate
  • maintain normothermia & avoid shivering (causes muscle contractions)
  • PFT, EKG, transthoracic pacing should be available
130
Q

What drugs should be avoided in myotonic dystrophy?

A

propofol, methohexital, etomidate, neostigmine, physostigmine

*do not want to ↑ ACh at receptors

131
Q

What are mitochondrial disorders?

A

disorders of skeletal muscle energy metabolism;

132
Q

What are the s/s of mitochondrial disorders?

A
  • abnormal fatigability with sustained exercise
  • skeletal muscle pain and weeakness
  • hearing loss/impaired vision
  • balance & coordination problems
  • seizures
  • learning deficits
  • organ problems (heart. liver, kidney, brain- organs that require high energy)
133
Q

What type of work-up do pts with mitochondrial disorders need?

A

COMPREHENSIVE

134
Q

What is the treatment for mitochondrial disorders?

A
  • treat symptoms
  • administer metabolites & cofactors
  • sodium bicarb/dichloroacetate
  • ketogenic diet
135
Q

Can regional anesthesia be used in patients with mitochondrial disorders?

A

yes, as long as there are no spine, or PNS injuries/issues

  • do not prolong tourniquet use d/t metabolic by-products
136
Q

What benzodiazepine can cause mitochondrial depression?

A

midazolam

137
Q

What monitor should be used on patients with a mitochondrial disorder?

A

BIS

138
Q

Patients with mitochondrial disorders are prone to development of….

A

acidosis & dehydration

*make them first case of the day

139
Q

What kind of fluid should be used for patients with mitochondrial disorders?

A

normal saline. LR has lactate

140
Q

What medications should be avoided in patients with mitochondrial disorders?

A
  • midazolam
  • succinylcholine
  • LR
  • continuous infusion of propofol (bolus OK)
  • bupivacaine (higher cardiotoxicity)
141
Q

What medications should be used with caution in patients with mitochondrial disorders?

A

NDMR

local anesthetics

142
Q

What is Guillain-Barre?

A

immunologic assualt on myelin in the PNS, particularly the lower motor neurons.

AP cannot be conducted so motor end plant does not receive signal.

143
Q

What are the s/s of guillian-barre?

A

flaccid paralysis that beings in the distal extremities and ascends

sensory deficits

autonomic dysfunction is present

  • resting tachycardia
  • spontaneous diaphoresis
  • vasodilation
144
Q

What is the treatment of Guillain-Barre?

A

plasmapheresis
IVIG

*steroids are NOT useful; they inhibit the scavengers that HELP increase nerve regeneration

145
Q

What are anesthetic considerations of Guillain-Barre?

A
  • AVOID succinylcholine d/t denervation
  • RISK of aspiration, DVT,
  • increased sensitivity to NDMR
  • exaggerated response to indirect sympathomimetics (place a-line for monitoring)

*regional anesthesia is controversial

146
Q

What is spinal muscular atrophy?

A

gene mutation of 5q13; loss of SMN gene promotes apoptosis of lower motor neurons (anterior horn of the spinal cord)

147
Q

What gene is implicated in spinal muscular atrophy?

A

survival motor neuron gene on chromosome 5q13

148
Q

What is SMA type I

A

autosomal recessive

diagnosis within 3months of life

difficulty swallowing, sucking, breathing

atrophy/fasciculation of tongue & limbs

rapidly progressive with death by age 3

149
Q

What is SMA type 2

A

autosomal recessive

diagnosed 3mo-2y

progresses more slowly, can survive until adulthood

150
Q

What is SMA type 3

A

juvenile form that develops after age 2.

weakness of proximal limb muscles with relative sparing of bulbar muscles (head & neck)

151
Q

What is the treatment of SMA?

A 
Spinraza
Zolgensma
Evrysdi
Physical therapy
surgery
antibioticss
152
Q

What are anesthetic considerations of SMA?

A
  • pulmonary consult
  • difficult intubation
  • avoid succinylcholine
  • NDMR have longer DOA; varying sensitivity
  • regional is controversial; neuraxial difficult/unreliable
  • caution with opioids
  • anticipate post-op respiratory support
153
Q

What is a mixed motor neuron disease?

both upper motor neuron and lower motor neuron

A

Amyotrophic lateral sclerosis

154
Q

What is amyotrophic lateral sclerosis?

A

rapid, progressive degeneration in the corticospinal tract (primarily the descending upper motor neurons) and the lower motor neurons in the anterior grey matter of the spinal cord.

*astrocytic gliosis replaces the affected motor neurons

155
Q

What are s/s of amyotrophic lateral sclerosis?

A
  • spasticity, hyper-reflexia, loss of coordination, weakness, fasciculations
  • atrophy begins in hands
  • orthostatic hypotension
  • resting tachycardia

-**SENSATION REMAINS INTACT

156
Q

What is the treatment of amyotrophic lateral sclerosis?

A

Riluzole (NMDA receptor antagonist)
Edaravone (decreases the decline of ADLs)
spasmolytics
analgesics

157
Q

What are anesthetic considerations of amyotrophic lateral sclerosis?

A

AVOID succinylcholine

  • increased sensitivity to NDMR & respiratory depressants
  • aspiration risk
  • consider post-op ventilation
  • AUTONOMIC DYSFUNCTION with risk of hemodynamic instability

*** AVOID SPINAL ANESTHESIA

158
Q

In what neuromuscular diseases should spinal/epidural be AVOIDED?

A

AML
Multiple sclerosis (avoid spinal; epidural OK)
Mitochondrial disorders (ensure no existing injuries/issues)
Guillain-Barre
SMA (controversial)

N935 Advanced Pathophysiology (9 decks)

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