Neuromuscular disorders

Question 1

What are upper motor neurons?

Answer 1

pathways completely contained within the CNS

cerebral cortex –> ventral horn of spinal cord

Question 2

Primary role of upper motor neurons

Answer 2

influence

1. reflex arcs,
2. low-level control centers &
3. motor neurons (some sensory)

Question 3

Corticospinal tract supplies what

Answer 3

voluntary muscles of the trunk and extremities

Question 4

corticospinal pathway

Answer 4

precentryal gyrus
internal capsule - midbrain - pons
90% decussate in medulla –> lateral corticospinal
10% decussate low @ s/c –> ventral corticospinal

Question 5

corticospinal synapse w/

Answer 5

spinal nerves

Question 6

ventral corticospinal tract ?

Answer 6

posture

Question 7

corticobulbar tract supplies what

Answer 7

voluntary muscles of head

same pathway of corticospinal UNTIL brainstem

Question 8

corticobulbar pathway

Answer 8

precyntral gyrus
CN 3, 4, 6, 9, 10, 11 bilaterally
CN 7, 13 unilaterally (facial & hypoglyssal)

Question 9

where are lower motor neurons located?

Answer 9

brain stem or spinal cord

Question 10

what do lower motor neurons do?

Answer 10

direct influence on muscles! they send out axons via nerves in PNS to synapse on sk. muscles

Question 11

lower motor neurons passing through spinal nerves control…

Answer 11

muscles of limbs/trunk

Question 12

lower motor neurons passing through cranial nerves control….

Answer 12

sk muscles of head/neck

Question 13

umn (pyramidal cells) motor cortex

Answer 13

• muscle groups affected, mild weakness, minimal disuse muscle atrophy
• no fasiculations
• hypertonia & spasticity
• increased stretch reflex, + babinski

Question 14

lmn ventral horn (S/C) and motor nuclei (brainstem)

Answer 14

individual muscles affected

• mild weakness, marked muscle atrophy
• fasciculations
• decreased stretch, hypotonia, flaccid
• no babinski

Question 15

name 5 umn diseases

Answer 15

cp, cva
ms
parkinson’s
huntington’s

Question 16

cp patho

Answer 16

non-progressive disorder caused by injury/abnormal development in the immature brain before, during, or after birth for up to a year

Question 17

what path is affected by cp

Answer 17

corticospinal

Question 18

s/s cp

Answer 18

muscle weakness
no speech, drooling
exaggerated DTR, spasticity, rigidity
scoliosis, contractures

vision/hearing
swallowing , sz, slow
gerd

Question 19

cp treatment (4)

Answer 19

no cure - s/s treatment only
dorsal rhizotomy
antireflux
intrathecal baclofen
botulinum toxin

Question 20

cp anesthesia

Answer 20

hold sedatives, opioids (short acting only)
vascular access sucks
difficult airway
RSI
sux - usually ok, but 30% do have extrajunctional receptors
ndmr - if on anticonvulsants, resistant
mac decreased 20 - 30%
bleeding - antisz meds
hypothermia - no fat
dry
slow emergence
high risk for latex
no regional d/t scoliosis etc

Question 21

m/s patho

Answer 21

autoimmune
demyelination, inflammation, axonal damage of CNS
PNS ok

Question 22

s/s ms

Answer 22

paresthesia
muscle fatigue
muscle spasms
visual problems
ans dysfunction
bulbar muscle dysfunction
cognitive dysfunction - advnaced

Question 23

tx m/s

Answer 23

diazepam
dantrolene
baclofen
steroids
immunosuppresants
cd20 monoclonal abs, interferons, glatiramir

Question 24

s/s of m/s exacerbated by

Answer 24

stress
hyperthermia
infection
hyponatremia

Question 25

anesthesia & m/s

Answer 25

``` no sux, scopolamine, atropine nmdr: be careful no spinal block epidural is ok aspiration, dvt risk stress dose steroids exaggerated hypotensive effect ```

Question 26

anterior cerebral artery

Answer 26

contralateral leg weakness

Question 27

mca

Answer 27

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

Question 28

posterior ca

Answer 28

contralateral visual defect + hemiparesis

Question 29

penetrating arteries

Answer 29

contralateral hemiparesis & hemisensory deficits

Question 30

basilar artery

Answer 30

oculomotor deficits ataxia crossed sensory/motor

Question 31

vertebral artery

Answer 31

lower cranial nerve deficits ataxia crossed sensory

Question 32

cva tx

Answer 32

asa tpa (ischemic) surgery

Question 33

cva anesthesia

Answer 33

``` rsi dvt risk (use regional!) b/s b/p initially, pt has htn - don't rapidly decline their bp b/c cpp ```

Question 34

parkinson's patho

Answer 34

loss of dopaminergic fibers in basal ganglia | unopposed ach

Question 35

s/s parkinsons

Answer 35

tremor during rest rigid, akinesia diaphragmatic spasm, dementia facial immobility

Question 36

parkinson's tx

Answer 36

``` levodopa carbidopa amatadine selegiline + rasagiline (avoid meperidine, check b/s) COMti (lfts) antiviral amantadine prolongs QT ```

Question 37

anesthesia & Parkinsons

Answer 37

``` levodopa continue dos hypotension + arrhythmias or htn RSI, airway risk (post extubation stridor) hard sticks if on anticholinergic, ndmr less effective SEVOFLURANE ketamine if on ldopa direct acting pressors sux? ```

Question 38

huntington's patho

Answer 38

degenerative disease of CNS | marked atrophy of caudate nucleus + putamen + globus

Question 39

s/s huntington's

Answer 39

dementia - progressive chorea, tremors, rigid mood swings cant talk or swallow

Question 40

anesthesia & huntingtons (3)

Answer 40

rsi sux + nmdr prolonged avoid reglan, anticholinergics. atropine

Question 41

lmn (6)

Answer 41

``` mg muscular dystrophy myotonic dystrophy mitochondrial d/o g/b spinal muscular atrophy ```

Question 42

myasthenia gravis

Answer 42

autoimmune (igg) against the nachr

Question 43

m/g s/s

Answer 43

diplopia, ptosis fluctuating fatigue/weakness imrpoves w/rest face weakness

Question 44

m/g tx

Answer 44

``` pyridostigmine (cholinesterase inhibiotr) plasmapheresis steroids immunosuppresants thmectomy ```

Question 45

m/g and anesthesia

Answer 45

aspiration risk ndmr sensitivity regional preferred (amides) resistant to sux

Question 46

lems s/s (3)

Answer 46

proximal muscles are affected most weakness worse in a.m., gets better during the day resp/diaphragm weakness and dysfunction

Question 47

lems & anesthesia

Answer 47

sux and ndmr sensitivity bad reversal w/acei lots have small cell carcinoma

Question 48

duchenne s/s

Answer 48

``` kyphoscoliosis degeneration of cardiac muscles/impaired conduction gi hypomotility/decr. airway reflex pulm htn cognitive impairment ```

Question 49

becker s/s

Answer 49

less slowness | proximal muscle weakness

Question 50

tx of musc. dystrophy

Answer 50

steroids, biphosphates | mystatin or protease inhibitors

Question 51

m/d anesthesia

Answer 51

tiva sensitive to ndmr local/regional yay aspiration risk

Question 52

myotonic dystrophy

Answer 52

hereditary disease of sk. muscle resulting in dysfunctional ca+ sequestration by SR. na/chl also involved

Question 53

myotonic dystrophy s/s

Answer 53

distal limb weakness, myotonia, face/thorax/intercostal/diaphragm ``` cardiomyopathy, conduction defects endocrine central sleep apnea ptosis male triad (balding, cataracts, sm. testes) ```

Question 54

myotonic dystrophy tx

Answer 54

procainamide/phenytoin baclofen/dantrolene carbamezepine/cardiac pacemaker

Question 55

myotonic dystrophy & anesthesia

Answer 55

no sux do a tiva myotonia aggravated by neo/physo have pacing at bedside, they vagal lots

Question 56

mitochondrial d/o

Answer 56

heterogenous group of d/o of sk. muscle energy metabolism mitochondria produce energy required by sk. muscle cells through the oxidation-reduction reactions of etc and oxidative phopohrylation

Question 57

mitochondrial d/o s/s

Answer 57

fatigue, muscle pain hearing loss balance, sz, learning deficits organ problems

Question 58

mitochondrial d/o tx

Answer 58

give metabolites & cofactors sodium bicarb/dichlloroacetate ketogenic diet

Question 59

mitochondrial d/o anesthesia

Answer 59

``` acidosis, dehydration lactate high avoid sux, LR, prop gtt nmdr&LA - be careful no bupi ```

Question 60

GB

Answer 60

sensory deficits, ans dysfunction

Question 61

GB tx

Answer 61

plasmapheresis ivig NO STEROIDS

Question 62

gb & anesthesia

Answer 62

``` no sux sensitive to ndmr dvt increased risk siadh don't use indirect sympathomimetics ```

Question 63

spinal muscle atrophy

Answer 63

d/t deletions or mutations in the survival motor neuron gene. this gene product is involved in the formation of rna complexes & their trafficking out of the nucleus loss of smn function promotes apoptosis of lmn & affect anterior horn of s/c

Question 64

sma & tx

Answer 64

spinraza/zolgensma/evrydsi give abx early

Question 65

sma. & anesthesia

Answer 65

difficult intuation no sux nmdr prolonged

Question 66

als s/s

Answer 66

atrophy in hands resting tachycardia snesation ok

Question 67

als tx

Answer 67

riluzole, edavaone spasmolytics analgesics

Question 68

als anesthesia

Answer 68

avoid sux nmdr prolonged ans dysfunction no spinal anesthesia