Amyotrophic Lateral Sclerosis Flashcards
Describe the ALS Functional Rating Scale (ALSFRS-R)
- Minimum detectable change = 6.74 points
- Minimum clinically important differences = a 20% decline in ALSFRS-R is generally considered clinically significant
Epidemiology of ALS
- Most physically devastating of the neurodegenerative diseases
- Cause unknown
- Slightly more common in men than women
- Average age of onset is mid 50s
How does Jean Martin Charcot describe ALS
- Disorder of muscle wasting and gliotic hardening sclerosis of the anterior & lateral corticospinal tracts involving both upper and lower motor neurons
Describe motor neuron diseases
- Only upper motor neurons damaged = primary lateral sclerosis
- Only lower motor neurons damaged = spinal muscular atrophy or progressive muscular atrophy
- Both upper and lower motor neurons damaged = amyotrophic lateral sclerosis (ALS)
Decisions regarding care across the continuum are influenced by
- Stage of disease
- Availability of disease modifying agents
- Time of disease onset
- Patient factors: goals, psychosocial factors, social and financial resources
- Nature & course of the disease
- Individual variability through course of disease
Different signs for suspected, probable, and definite ALS
- Suspected ALS: LMN only in one region or UMN only in one region
- Probable ALS: LMN + UMN in one region (identify gene defect); LMN + UMN in 2 regions; LMN + UMN in 1 region or UMN only in 1 region
- Definite ALS: LMN + UMN in 3 regions
Describe ALS
- Affects both UMN and LMN
- Generally accepted that sensory nerves are normal
- Distal motor latencies & slowing of conduction velocity worsened as the severity of muscle weakness increased
- Will not show up on imaging
Diagnosis of ALS requires the presence of
- Signs of LMN degeneration: electrophysiological or neuropatholgic exam
- Signs of UMN degeneration: clinical exam
- Progressive spread of signs within a region or to other regions with absence of electrophysiological evidence of other disease processes and absence of neuroimaging evidence of other disease processes
- Overall diagnosis is a combination of clinical presentation & EMG
EMG criteria for diagnosis of ALS
- Fibrillations
- Positive waveforms
- Fasciculations
- Motor unit potential changes in multiple nerve root distributions in at least 3 limbs & the paraspinal muscles
- These changes occur without change in sensory response
Time to diagnosis of ALS differs according to 1st presenting symptoms
- UE onset: 15 mo
- LE onset: 21 mo
- Bulbar onset (UMN/speech, breathing, swallowing functions impacted): 17 mo
Steps in the Dx of ALS
- Hx, physical & appropriate neurological exams to ascertain clinical finding
- Electrophysiological exams to ascertain findings which confirm LMN degeneration
- Neuroimaging exams to ascertain findings which may exclude other disease processes
- Clinical laboratory exams determined by clinical judgement
- Neuropathologic exams
- Repetition of clinical & electrophysiological exams at least 6 mo apart to certain evidence of progression
Risk factors for ALS
- Family Hx: heritability is estimated 61%
- Genetic risk factors: C9ORF72 gene, SOD1 gene, & TARDBP gene
- Viruses
- Occupational/environmental risk factors: military service & environmental exposure
- Lifestyle: smoking, lower risk with higher intake of antioxidants & polyunsaturated fatty acids, lower BMI & increased physical fitness, professional athletes
Describe the inflammation.infection theory of development of ALS
- Whether inflammatory mechanisms are one of the primary causes of ALS or secondary to other pathological mechanisms is unclear.
- Inflammation can be triggered by invading microbes such as viruses or bacteria; injurious chemicals, or by physical injury.
- The trigger may come from within the organism such as a disease affecting the immune system or nervous system
Describe the excess glutamate theory of development of ALS
- You need a certain amount of glutamate for motor nerves to communicate, but too much can be toxic to nerve cell bodies.
- People with ALS have too much glutamate in their spine and the excess glutamate damages the motor neurons.
- A major area of ALS research has been aimed at finding drugs that will reduce the amount of glutamate in the synaptic area between neurons
Slides 23-26
Clinical presentation fo ALS
- Most frequent initial symptom is focal weakness beginning in the leg, arm, or bulbar muscles
- Absence of sensory symptoms and findings
- Cognition, extra ocular eye movements, & autonomic, bowel, bladder, & sexual functions usually remain intact
- Muscle weakness progresses over time
- Pts must cope with continual, multiple functional losses f speech, swallowing, ability, ADLs
Death from ALS usually result from _______________ with 50% of patients surviving only _________ after onset of symptoms unless mechanical ventilation is used to sustain breathing
- Respiratory failure; 3-4 years
Patients with Bulbar Palsy generally have a ________ rapidly progressive clinical course
- More
Describe the pathogenesis of ALS
- Speculates overstimulation of nerve cells by excessive amounts of glutamate could lead to cell death
- Immune system may be involved
- Pathogenesis is complex & remains unknown
- No cure exists but medications have beneficial effects: Riluzol (Rilutec) provides modest survival benefit and Myotrophin (insulin like growth factor-I) moderately lessens noter dysfunction
UMN signs
- Spasticity: clonus
- Hyperreflexia
- Pathologic reflexes: Hoffman and Babinski
LMN signs
- Muscle weakness
- Muscle atrophy
- Fasciculations
- Hyporeflexia
- Hypotonicity
- Muscle cramps
Bulbar signs
- Dysphagia
- Dysarthria
- Pseudobulbar affect: uncontrolled crying/laughing in inappropriate times
- Pseudobulbar palsy: difficulty chewing/swallowing and inability to control facial movements
- Sialorrhea: excessive production of saliva
Respiratory signs and symptoms of ALS
- Nocturnal respiratory difficulty
- Exertion dyspnea
- Accessory muscle use
- Paradoxical breathing
Other signs and symptoms of ALS
- Fatigue
- Weight loss
- Cachexia: weakness/wasting of the body
- Tendon shortening
- Joint contractures
Disorders that can mimic ALS
- Myasthenia Gravis
- Cervical Myelopathy
- Multifocal Motor Neuropathy
- Hypoparathyroidism
- Inclusion Body Myositis
- Bulbospinal neuronopathy
- Lymphoma
- Radiation-induced effects
Define rehabilitation
- The process of assisting people to reach their fullest potential despite the presence of a disability
Describe the interdisciplinary team approach for ALS
- Diagnosis: breaking the bad news
- Psychological and spiritual support
- Treatment of symptoms
- Complex symptom management (gastrostomy, ventilation)
- End of life decision making
- End of life care
- Bereavement support
Slide 37
Describe the problem oriented approach
- Goal is to focus on what the pt needs most at any particular time in the course of the disease to maintain max function & QOL
- Critical to frequently reassess rehab strategies & modify them according to changes in disease status
- Best to address specific problems as they arise
How to answer can exercise make me stronger
- Mod intensity is safe for ALS pts
- Overexertion should be avoided
- Exercise is unlikely to make muscles significantly stronger in ALS & high intensity weight training should be discouraged
- Gentle restorative exercise can be used as a tool to avoid further reconditioning & as a means to improve sleep & mood
Slide 40
Describe the Steve Gleason Enduring Voices Act
- The Act will permanently fix the current Centers for Medicare & Medicaid Services (CMS) policy limiting access to Speech Generating Devices (SGD_ for people with degenerative disease
Describe stage 1 of ALS
- Early stages of disease
- Patient is independent in mobility & ADLs
- Muscles are mildly weak
- Therapy includes: pt & caregiver edu, energy conservation training, modification of the home/workplace, & psychological support
- Pt is advised to continue normal physical activities
- AROM/stretching of affected joints
- Resistive strengthening exercises of unaffected muscles w/ low to mod weights
- aerobic activities at sub max levels may be prescribed
What are the stages of grief
- Denial
- Anger
- Depression
- Bargaining
- Acceptance
Slide 47
Describe stage 2 of ALS
- Mod muscle weakness
- Assess need for appropriate equipment/AD
- Pt is encouraged to continue stretching/AROM, strengthening exercises of unaffected muscles, & aerobic activities
- AAROM and PROM exercises of affected joints to prevent contractures
- Consider prevention of overuse fatigue & disuse atrophy
- Highly repetitive/heavy resistance exercise can cause permanent loss of force in weakened/denervated muscle
- Marked reduction in activity level 2ndy to ALS can lead to CV deconditioning & disuse weakness beyond the amount caused by the disease
- Prevent excessive fatigue
- Exercise programs may be physiologically & psychologically beneficial for pts with ALS
- Advise to exercise for several brief periods throughout the day with rest b/w
- 30-45 min of total daily exercise (divided into 2-3 sessions)
- Cramping or fasciculations bc of ALS may indicate overuse
Slide 49
Describe stage 3 of ALS
- Pt is ambulatory but has severe weakness that may result in severe foot drop or marked hand weakness
- May be unable to stand from chair w/o help
- Pt exhibits mild to mod limitation of function
- Goal is to keep pt physically independent
- Adaptive equipment may be needed
- Pt may begin to report heaviness/fatigue while holding their head up
- Wheelchair may become necessary to avoid exhaustion
Slide 53-55
Describe stage 4 of ALS
- Pt uses a wheelchair due to severe weakness of arms & legs
- PROM/AAROM recommended to prevent contractures
- Continue strengthening/AROM of noninvolved muscles
- Decreased general mobility
- Need to inspect the skin for pressure areas increases
Describe stage 5 of ALS
- Progressive weakness & deterioration of mobility & endurance
- Pt uses wheelchair when out of bed
- Mod to severe arm muscle weakness
- Transferring the pt to & from a wheelchair becomes a major effort & a lift may be necessary
- Pts become unable to move themselves in bed thus frequent repositioning & skin care by caregiver is necessary
- Pain may become a major problem in immobilized joints
- Pain can be due to spasticity, muscle cramping, contractures, joint hypo mobility, and/or joint instability
- Pts may be unable to hold their head up for extended periods
- By maintaining the head in a neutral position, breathing, eating, & seeing may be facilitated
Slide 58-60
Progression of assistive devices
- Single point cane or walking stick
- Quad cane
- Rolling walker with or without a seat
- Manual wheelchair
- Power wheelchair
Slide 62
Slide 64
Diaphragm weakness first manifests as nocturnal hypoventilation leading to
- Interrupted sleep
- Increased anxiety
- Early morning headaches
- Excessive daytime fatigue
Most patients with ALS remain asymptomatic until their vital capacity (VC) is less than ____ of predicted
- 50%
ALS patients cannot lie flat because as the disease progresses
- Orthopnea with inability to lie flat due to difficulty breathing
- Dyspnea on exertion & eventually shortness of breath when sitting
- Weak cough & difficulty clearing secretions are associated symptoms
- Hypophonia: a soft voice as sufficient respiratory support is needed to speak loudly
Describe stage 6 of ALS
- Pt must remain in bed & requires max assistance with ADLs
- Pain management continues to be important
- Frequent repositioning to prevent uneven pressure & venous stasis in the legs
- “Head drop” from weak neck extensor muscles may become a major problem
- Progressive respiratory distress
- Cardiopulmonary PT techniques may be required
- Goals are similar to those of hospice/palliative care: address the pt’s & caregivers’ needs & to max the quality of each day
Benefits of non-invasive ventilation in ALS patients
- Should be considered to treat respiratory insufficiency to lengthen survival & slow the decline of forced vital capacity
- Improves QOL
- Early initiation of non-invasive ventilation may improve compliance
- Insufflation/Exsufflation may be considered to help clear secretions