Neuromuscular disorder Flashcards
(32 cards)
Anatomy - Neurons
Nervous system - CNS (brain, spinal cord, cranial nerve 1-2), PNS (cranial nerve 3-12, spinal nerves, ANS)
Neurons = primary functional unit of nervous system that can excite, conduct and influence other neurons
Myelinated for rapid propagation and protection
Transmits nt across synapse
- GABA = inhibitory
- Glutamate/ACTH = excitatory
- Dopamine, NE, serotonin = both
Brain
1) Motor cortex - goal orientated movement/tasks
2) Basal ganglia - in cerebrum for movement
3) Cerebellum - motor control, coordination and balance
Spinal cord
Ascending pathway - sends sensory info to brain
Descending pathway - sends motor info to nerves
Spinal/peripheral nerves
i) Sensory/Afferent - ascending tract
ii) Motor/Efferent = descending tract
- Pyramidal neurons = voluntary movement
- Extrapyramidal neurons = involuntary movement (dysfunctional in parkinsons)
1) Upper motor neurons - between brain and spinal cord
2) Lower motor neurons - spinal cord to muscle
SAME DAVE
Sensory/afferent/dorsal
Motor/efferent/ventral
Multiple sclerosis
Autoimmune disorder that damages myelin sheath
- chronic inflammation and scarring of CNS that slows/blocks signals and impulses
- Periods of remission and exacerbations
Risk factors
- Female
- Vit d deficiency/cold climates
- Age onset of 30
- Genetic
Precipating factors
- Infection, poor health
- trauma, surgery
- Pregnancy
- Stress, fatigue
Clinical manifestations of MS
- Tinnitus
- Emotional lability - rapid exaggerated changes in mood
- Apathy - impassiveness
- Scanning speech/Spasmodic dysphonia
- Diplopia
- Nystagmus
- Dysarthria = weak speaking muscles
- Dysphagia
- Atrophy
Parkinsons disease
Neurogenerative disease caused by lack of dopamine producing neurons that is required for extrapyramidal motor system
Risk factors
- Age of 60
- Male
- Antipsychotic meds
- Illicit drug use
- Dementia
- Exposure to chemicals
Clinical manifestations of Parkinsons
i) Tremors - pill rolling motion
ii) Rigidity
iii) Bradykinesia - lack of posture, deadpan, shuffling gait, drooling
Stages vary from initial, mild, moderate, severe and complete ADL dependency
Complications
- Aspiration/pneumonia
- UTI
- Pressure sores
- Malnourishment
- Falls
Spinal nerves (dermatomes/myotomes)
Motor+sensory
- Grey matter - voluntary and autonomic motor neurons
- White matter - sensory/motor (ascending/descending tracts)
Dermatomes = area of skin
Myotomes = muscle groups
Spinal cord injury (SCI)
Disruption in neuronal tissue within spinal canal as result of trauma, disease or degeneration (eg. disease, tumors, decreased blood supply, infection, etc.)
Classified by
i) Mechanism of injury
ii) Level of injury
iii) Completeness of degree of injury
Level of injury
1) Skeletal level of injury
2) Neurological level of injury
i) Tetraplegia = paralysis of arms, legs, trunk
- Damage of C8 and above
- C4 and above is total loss of respiratory muscle = ventilation required
ii) Paraplegia = paralysis of legs and trunk
- Damage between T1-T6
- Above T6 - Cardiovascular changes - bradycardia/hypotension
Clinical manifestations of SCI
- DVT (from immobility)
- Respiratory changes and cardiovascular changes
- Urinary system, GI system like ulcer from steriods, paralytic ileus
- Skin breakdown
- Poikilothermia - temp regulation matches room tempP
Peripheral neuropathy
Neuropathic pain from destruction or inflammation
i) Mononeuropathy
-Postherpatic neuralgia - pain after blisters are healed eg. shingles
ii) Polyneuropathy
- Viral infection
- Botulism - neurotoxin exposure (Ragid)
- Tetanus - neurotoxin exposure (spasm)
Causes
- Diabetes : ischemia, inflammation
- Hypothyroidism
- Vitamin deficiency (Vit B12)
- Lyme disease
- Multiple sclerosis
- Mononeuropathy = impingement of nerve such as carpal tunnel
= clinical manifestation depends on what dermatome/myotome is effected
Clinical manifestations of SCI
Sensory and motor dysfunction
- Poorly localized
- Shooting, burning, fiery
- Shock-like tingling painful
- Numbness
- Sensitive to touch
- Weakness, paresthesia
Autonomic dysfunction
- Bowel, bladder, digestive dysfunction
- Heat intolerance
- HypotensionL
Levodopa/Carbidopa
Parkinsons
- Levodopa = Coverted to dopamine (but does not cure disease, only delays progression), effectiveness decreases over time
- Carbidopa = Decarboxylase inhibitor
AE
- N/V = direct stimulation of CTZ w dopamine
- Dyskinesia = can cause movement disorders, usually in long-term therapy (5-10 yrs)
- Postural hypotension
- Psychosis
-CNS effects - anxiety, agitation, memory loss, cognitive impairment,
- Darken sweat and urine
NC
- Avoid protein = competes with amino acids in absorption of the small intestines
- Assess extrapyramidal
- Monitor BP
- Fall risk - educate to stand up slowly
Acute loss of effect in Levodopa/Carbidopa
1) On/off phenomenon
- Abrupt return of PD symptoms
- Not dose dependent
Minimize by
- Dopamine agonist/MAO-b inhibitor
- Minimize protein
2) Wearing off phenomenon
- Gradual return = is dose-dependent
Minimize by
- Increase dose frequencies (shorter intervals)
- MAO-B inhibitor (prolong half life), dopamine agonist
Pramipexole (Mirapex)
Dopamine receptor agonist
MOA - Stimulate dopamine receptors, usually first line drug as not broken down before BBB, does not compete with amino acid, lower dyskinesia
- Take several weeks to develop however
AE
- Dopamine receptors - naursea, dizzy, nausea, sleepy
- Othostatic hypotension, hallucination and dyskinesia risk increases when taken with levodopa
- Sleep attacks!!!!! = drug must be stopped immediately
- Impulse control disorders - hypersecuality, gambling, binge eating
NC
- PO
- Risk of drowsiness - avoid dangerous activities and CNS depressants
- Monitor BP regualrly
Selegiline (Deprenyl)
MAO-B inhibitor
MOA - stops the enzyme MAO-B that breaks down dopamine
- Benefits with levodopa only works for 1-2 yrs
AE
- Insomnia
- Hypertensive crisis, esp in young people and high disease
- Worsen orthostatic hypotension, psychiatric and dyskinesia with levodopa
NC
- PO
- DO NOT take with meperidine or SSRI or opioids = serotonin syndome
Anticholinergics
MOA - blocks ACTH, improves tremors but NOT bradykinesia
AE
- Blurred vision, dry mouth, constipation, urinary retention (SNS)
NC -
- Elder develop dementia (not prescribed if older than 70)
Methylprednisolone (Solu-medrol)
Multiple sclerosis exacerbation
MOA - mimic cortisol for antiinflammation
- Prednisone in IV form
NC - monitor signs of acute infection as masks it, adrenal suppression, hyperglycemia, hypertension
Interferon (Betaseron)
Immunomodulator (better)
MOA - glycoprotein that prevents leukocytes crossing BBB and suppress T-helper cell
AE
- Flu-like symptoms (HA, fever, chills, malaise etc) = decreases over time, give Tylenol
- Hepatoxic
- Myelosuppression
- Depression/suicidal ideation
CI - liver disease, alcoholism, depression
NC
- IM/Subcut
- Avoid hepaptoxic drugs, monitor CBC/LFT before, 1/3/6 months
Mitoxantrone (Novantrone)
Immunosuppressant
MOA - CYTOTOXIC
- binds to DNA and kills rapidly dividing cells
plz don’t confuse with methotrexate they arent the sameeeeee
AE
- Myelosuppression
- Hepatoxic
- Cardiotoxic!!!
- Hair loss, N/V, mouth sores (pretty similar to cancer drugs)
NC
- Clinic - dose every 3 months for 2-3 yrs only cause so toxic
- Monitor GI - Antiemetic prophylactically
- Fluid/electrolytes, intake, output, all that fancy stuff
- EKG, chest cray, echo for EF before, during therapy
- IV administration - PPE required
- Immediately stop is pain, swelling, redness = extraversion
Baclofen (Lioresal)
MS and SCI - Skeletal muscle relaxant
MOA - Replicate inhibitory GABA to suppress hyperactive reflexes
AE
- CNS depressant (improves over time)
- DO NOT STOP ABRUPTLY - Withdrawal symptoms like hallucination, seizures, paranoid ideation, taper over 1-2 weeks
- N/V
- Constipation, urinary retention
- Orthostatic hypotension
NC
- Oral or inthecal (into spinal fluid but higher risk of severe symptoms like fever, muscle rigidity, rebound spactiy, MOF, death)
- Caution with other CNS depressenat = Respiratory depression
Gabapentin
Antiseizure med for neuropathic pain
MOA - Analog of gaba
AE - Well tolerated
- fatigue, ataxia, nystagmus, edema, dizzy = wears off usually
- Suicidal ideation
- Slow taper as risk of seizure if abruptly stopped
NC - Monitor for signs of CNS depresson, suicide etc
