GBS Flashcards
Axonopathy: definition, chronic examples
Wallerian degeneration of the axon
Acute- regrowth = 3-4mm/day
Cronic- no regrowth: DM, toxins, hereditary (CMT)
Myelinopathy: definition, examples
degeneration of myelin producing cells (Schwann- peripheral, oligodendrocytes- central)
example = GBS
Neuronopathy: definition, examples
damage to the cell bodies (no regrowth possible)
examples = ALS, SMA, Polio
Neuropathic Weakness
weaker distal > proximal
example = polyneuropathy (GBS)
Myopathic Weakness
weaker proximal > distal
Cause of Mortality in GBS
inability to breath; complications from respiratory or autonomic issues
Etiology/Pathology of GBS
Autoimmune illness
inflammatory process –> T cells create antibodies that target myelin and the axons –> macrophages destroy schwann cell or axon
Clinical symptoms of GBS used in diagnosis
Flaccid paralysis, symmetrically ascending (no spasticity) Respiratory failure and ANS dysfunction diminished or absent DTRs slowed nerve conduction velocity CSF with elevated proteins nonspecific lab tests
3 clinical subtypes of GBS
AIDP- acute inflammatory demyelinating polyneuropathy
AMAN- acute motor axonal neuropathy
AMSN- acute motor-sensory axonal neuropathy
AIDP
only myelin affected (demyelination) Motor neurons > sensory (but could be reversed) most often in western hemisphere (80%) EMG = prolonged motor response *best prognosis
AMAN
20% (2nd most common type in western hem) axonal damage (degeneration) EMG = decreased conduction velocity, + spike waves
AMSAN
Rare! Axon affected (degeneration) EMG = decreased conduction velocity, + spike waves
Miller-Fisher Syndrome
Allied with GBS
more brainstem involvement- cranial nerves > axial muscles
issues with eye movements, swallowing, facial movements
Only way to know type of GBS
EMG analysis!
AIDP- increased motor latencies
AMAN/AMSAN- decreased conduction velocity, (+) spike waves
Recovery period for GBS
up to 2 years
Poorer outcomes associated with:
- Quadriplegia
- respiratory dependency > 1m
- failure to show improvement within 3 weeks of plateau
- AMAN/AMSAN v AIDP
3 temporal phases of GBS
Acute/Before stabilization –> deterioration
Nadir/Plateau phase –> stabilization
Recovery phase –> acute care - rehab/homecare/OP
Acute/Before stabilization stage
- location/what’s happening
- pattern of weakness
- peak weakness
deterioration- in ICU
symmetrical, ascending weakness
Peak of weakness: 3-21 days
Nadir/Plateau Phase
- location/what’s happening
- peak weakness
stabilization/quiet period- in ICU (ventilation) or ward (no ventilation)
lowest the pt will get (functionally)
Recovery Phase
- location/what’s happening
- duration
- pattern of return
location depends on severity (could be in the ICU if weaning off ventilator)
up to 2 yrs
Return in reverse order: proximal before distal
5 phases of Pt’s Perspective of Recovery
- Experiencing dependency (unable to do anything)
- Encountering helplessness
- Wanting to know more about GBS (most at rehab level)
- Discovering inner strength
- Regaining independence
Hughe’s Disability Scale:
Purpose
Study that followed pts in the UK findings
Grades GBS based on functionality/presence of temporal summation
UK study found that:
1. more acutely, more impaired, many on ventilator
2. by 2 years, no one on ventilation, some in w/c, all becoming less impaired
Hughe’s Disability scale: Ordinal scale
0 = healthy, all functional activities as before 1 = minor signs or symptoms, able to run 2 = able to walk > 10m without symptoms, unable to run 3 = able to walk more than 10m with assistance 4 = requires wheel chair 5 = requiring assisted ventilation for at least part of the day 6 = dead due to GBS
Why is running a good criteria for ability to recruit more and have temporal summation
Running requires speed, which requires at least 1 of 2 things:
- increase firing rate: temporal summation (rate coding)
- requires myelin to send down AP - increase # of muscles firing: engaging more alpha motor neurons (recruitment)
Plasmaphoresis: how long is it administered, what is done?
administered for 5 days to eliminate items in plasma causing inflammation
- all blood withdrawn
- replace plasma with saline and electrolytes
Intravenous Immunoglobulin: how long is it administered, why?
3-5 days, to prevent immune system from attacking
Standard of acute care in GBS (medically)
Plasmaphoresis and Intravenous immunoglobulin
Is neuropathic pain a potential issue for GBS pts?
yes! inflammatory process is occurring along the nerves
What is the distribution of pain?
Stocking glove distribution
Which types of muscles are particularly painful to stretch?
2 joint muscles (HS)
Specific areas of interest in integumentary system
EARS
heels
no ER of feet - fibular head
Autonomic dysfunction: symptoms to be aware of
decreased temperature regulation
impaired HR response (may be racing)
Orthostasis (unstable BP)
3 settings where pt might enter respiratory distress when exercising on the ventilator
- routine exercises when weaning off ventilator
- new exercise or activity performed at usual setting
- progressing difficulty at same setting
Rehab goals: Compensation or restoration?
Both! ideally you want restoration, but if you want them to be functional they may need to compensate for muscles that haven’t returned yet
Strengthening issues
- Core is critical for all movements (limbs overworked)
- Train fast-twitch fibers for force production (speed and force training)
- No Eccentric work until anti-gravity strength! (avoid DOMS- results in dec. strength)
- submaximal exercise with small reps + sets
Definition of submaximal exercise:
in LE and UE
appropriate reps and sets
LE: 30% or 40% max
UE: 10%, 15%, or 20% max
Reps: 4, 6, 8 with small sets
When to begin training in anti-gravity positions:
Muscle must be at least a 3/5 - needs to handle resistance of the limb
3 residual syndroms in patients without full recovery
- severe parathesias, dyesthesias
- sensory ataxia
- foot drop + intrinsic hand weakness
Long term studies: what does recovery look like?
Full recovery with subclinical signs:
- speed/force issues
- “full”, but activities not as enjoyable/performed at same level
- recovery highly related to fast twitch fibers
Long term studies: what do pts with good recovery still report?
- Fatigue: can do everything, but get tired
2. Pain: residual
Chronic Inflammatory Demyelinating Polyradiculopathy (CIDP)
Recurrent form of GBS, acute and insidious
Looks like GBS at first, progression is much slower
steady decline in functioning: small recovery followed by another episode
CIDP PT intervention
requires more compensatory strategies
HEP of daily strengthening+ cycle/walking for 6 weeks –> shown to increase strength and diminish disabilty
