neurology Flashcards
seizure definition
a hypersynchronous activation of a group of neurons within the brain
isolated seizure definition
seizure lasting less than 5 mins
cluster seizure definition
2 or more seizures within 24hrs, with complete recovery in-between
status epilepticus definition
- seizures lasting longer than 5 mins
or - 2 seizures without complete recovery in-between
partial/focal seizure definition
asymmetric, one part of brain affected
partial/focal seizure clinical signs
- facial twitching
- hypersalivation
- behavioural changes
- consciousness maintained
simple-partial/focal seizure definition
no change in mentation
complex-partial/focal seizure definition
change in mentation
generalised (tonic/clonic) seizure definition
bilateral cerebral hemisphere involvement
generalised (tonic/clonic) seizure definition
bilateral cerebral hemisphere involvement
generalised (tonic/clonic) seizure clinical signs
- autonomic signs (urination/defecation)
- loss of consciousness
- pre-ictal, ictal and post ictal phases
pre-ictal phase of seizure (minutes)
- stage before seizure
- behaviour changes, altered mentation, attention seeking behaviour
ictal phase of seizure (<5 mins)
- loss of consciousness
- muscle contraction
- urination/defecation
post-ictal phase of seizure (mins-days)
- abnormal neurological signs
- wobbly, quiet, varies
extracranial causes of seizures
toxins
- slug bait, antifreeze, permethrin (cats), pesticides, ivermectin (collies), human drugs
metabolic
- portosystemic shunts, hypoglycaemia, hypercalcaemia
intracranial causes of seizures
structural
- brain tumour, inflammation, hydrocephalus
functional
- idiopathic epilepsy
idiopathic epilepsy
- most common causes of seizures
- animals diagnosed >6 months-6 years
- recurrent seizures
- normal inter-ictal neuro exam
- normal MRI, metabolic, CSF exam
diagnostics for seizures
- history
- bloods
- MRI with contrast
- CSF analysis
seizure mimic disorders
- narcolepsy/cataplexy
- fly-catching
- movement disorder
- syncope
- 3rd degree AV block
narcolepsy/cataplexy
- sleep-wake disorder
- inherited
- loss of muscle tone
- no autonomic signs
fly catching
- unknown cause
- minutes to hours
- normal mentation
- no autonomic signs
movement disorder
- episodic
- patient remains conscious
- spontaneous, involuntary movements
syncope
- fainting
- temp loss of consciousness
- due to reduced oxygen to brain
- cardiac/neuro/hypoglycaemia related
3rd degree AV block
- prolonged hypoxic event
- partial seizure like episodes
canine epileptoid cramping syndrome
- movement disorder common in border terriers
- conscious and responsive
- no autonomic signs
emergency management of seizures
- provide oxygen therapy
- place IV catheter
- diazepam 0.5-1mg/kg IV bolus, 2mg/kg rectally, 0.5mg/kg intranasally
- assess circulation and temp
- give mannitol IV if seizure lasts >15mins or cerebral oedema
- collect bloods
phone triage questions for seizures
- history of seizures
- exposed to any toxins
- head trauma?
- how long is the patient seizing for?
- how many seizures?
- is patient conscious and responsive
- autonomic signs? (urine, defecation)
- only transport patient when stable
nursing of seizure patients
- quiet ward
- lights dimmed
- bottom kennel (easy access when seizing)
- seizure plan on kennel with doses calculated
- seizure pack with medication drawn up
if patient seizures…
- note time
- call vet
- remove any dangers
- dim lights, reduce noise
- limit handling (just make them safe)
- monitor vitals
- don’t put hands in mouth
phenobarbital as medical management of seizures
- (epiphen)
- first line treatment, acts on GABA receptors in brain
- increases synaptic inhibition
- 2 weeks to become stable
side effects of phenobarbital for seizures
- hepatotoxicity (with high doses)
- sedation
- polydipsia/uria
- polyphagia
potassium bromide as medical management of seizures
- (libromide)
- first line anti-epileptic or in conjunction
- reduces neuronal excitability
- 4 months to become stable
side effects of potassium bromide as medical management of seizures
- gastric irritation
- nausea
- polydipsia/uria
- sedation
- pancreatitis
- can cause serious lung issues in cats
levetiracetam as medical management of seizures
- unknown method of action
- used as adjunct to other anti-epileptic drugs
- excreted unchanged in kidneys (fine with renal patients)
- orally bioavailable
- can cause ataxia, vomiting
imepitoin as medical management of seizures
- (pexion)
- only licensed for idiopathic epilepsy
- acts on GABA receptors reducing electrical activity
- can be used for noise phobias
- do not use in dogs with impaired hepatic, renal or CVS function
advice for clients
- nurse consult after initial diagnosis
- follow up calls to check in
- written communication
- support groups
- what does the owner need to know to care for pet at home
polyradiculoneuritis
- immune mediated disease
- affects myelin and/or axons (axonopathy)
- most common peripheral neuropathy in dogs
presentation of polyradiculoneuritis
- short-strided gate progressing to tetraparesis (weak limbs)
- dysphonia (change in voice)
diagnosis of polyradiculoneuritis
- accurate patient history
- physical and neuro exam
- EMG (electromyeligram)
- NCV (nerve conduction velocity)
- muscle and nerve biopsies
treatment of polyradiculoneuritis
intensive nursing care and physiotherapy
myasthenia gravis
- disease of neuromuscular transmission affecting NMJ (junctionopathy)
- congenital or required
- autoantibodies act on Ach receptor and alter function
- reduces number of functional receptors so muscles cant contract normally
- 3 types of the disease
presentation of myasthenia gravis
- muscle weakness and fatigue
- more obvious when exercising
- regurgitation due to oesophageal weakness
focal myasthenia gravis
- targets one muscle group
generalised myasthenia gravis
- targets all muscle groups
diagnosis of myasthenia gravis
- presumptive based on history and presentation
- thoracic radiographs- megaoesophagus
- edrophonium/tensilon test- patient can walk normally after
treatment of myasthenia gravis
- anticholinesterase therapy (bromides)
side effects: GI signs, hypersalivation
polymyositis
- immune mediated inflammatory myopathy
- infiltration of inflammatory cells into skeletal muscle
- idiopathic but can be associated with systemic disease
- focal (one muscle) or diffuse
presentation of polymyositis
- exercise intolerance and stiffened gate
- muscle atrophy, dysphonia, regurgitation (effects oesophagus)
- signs often wax and wane initially
diagnosis of polymyositis
- diagnosis of exclusion
- clinical history, biochemistry (increase in creatinine kinase), electrodiagnostic testing, muscle biopsy
treatment of polymyositis
- corticosteroids at immunosuppressive doses
- azothrioprine can be used along side steroids if patients cant handle their side effects
treatment of aspiration pneumonia
- early admin of antibiotics
- oxygen therapy, iv fluids
- walking, turning patients
- raised eating balls of food (wet food)
- mechanical ventilation if necessary
aspiration pneumonia
- inhalation of GI contents into lungs
- pulmonary damage and inflammation
- coughing, tachypnoea, crackles on auscultation
pressure sores
- common complication for recumbent patients
- increased pressure over bony prominences
- leads to ischaemia and necrosis
prevention of pressure sores
- thick padded bedding
- turning every 2-4hrs
- donut bandage
- porous bedding
- incontinence pads
- non slippery floors
- physiotherapy
treatment of pressure sores
- bandages and commercial boots useful
- debride if necessary
- antibiotics if infected
muscle contracture
recumbancy and immobilisation leads to:
- adaptive shortening of muscles and soft tissues
- inelasticity of soft tissues
considerations for neurological diseases
- temperament
- client expectations, limits
- disease process
- other diseases
spinal cord definition
extracranial part of CNS
spinal column definition
encases and protects spinal cord and nerves
patient workup steps
- history
- physical exam
- neuro exam
- differential diagnosis
- diagnostic tests
- diagnosis/prognosis
- treatment
when is a neuro exam indicated?
- seizures
- behavioural changes
- gait abnormalities
- change in posture, positioning
why is a neuro exam performed?
- identify if nervous system involvement
- identify specific location
- aid diagnosis and prognosis
- continuous assessment of conditions
upper motor neurons
- located between cerebral cortex and spinal cord
- send signals to lower motor neurons
lower motor neurons
- connect the CNS to effector muscle
- send signal to make muscle contract
ataxia definition
uncoordinated gait
paresis/paretic definition
weakness, decreased voluntary movement
paralysis/plegic definition
no voluntary movement
hemi- definition
both limbs on one side affected
para- definition
both pelvic limbs affected
quadra-/tetra- definition
all 4 limbs affected
head tilt definition
one ear is below the other
head turn definition
nose turned towards body
ventroflexion of neck
low head carriage
scoliosis definition
spine bends laterally
lordosis definition
spine deviates ventrally
kyphotic definition
spine arched dorsally
decerebrate rigidity definition
extension of all limbs, head and neck
decerebellate rigidity definition
extension of thoracic limbs, head and neck
proprioceptive positioning test
if you put the top of a patients paw on the ground, they should move it back to its natural position
hopping test
pick one leg off ground and make patient move from side to side
visual placing test
hold patient towards a table and place their paw on it
- patients should reach out for the table before their paw touches it
tactile placing test
cover patients eyes, gently brush their feet towards edge of table
- they should replace paw in natural position
hemi-walking test
front and back limbs on one side are lifted and supported whilst patient hemi walks to the side
spinal reflexes of thoracic limb
- withdrawal
- extensor carpi radialis reflex
- biceps brachii and triceps reflex
spinal reflexes of pelvic limb
- patella reflex
- cranial tibial and gastrocnemius
perineal reflex
perineum is pinched causing constricture
panniculus reflex
pinching either side of the spinal column (on skin) causing a twitch down the spine
deep pain
when patient doesn’t feel noxious stimuli due to damage or compression of spinal cord
deep pain evaluation
- pinch digit or nail bed on each limb
- looking for patient to react
- if no reaction (not including withdrawal reflex) they are deep pain negative
acute causes of spinal injury
- intervertebral disc disease (IVDD)
- trauma (fracture, luxation)
- infarction (fibrocartilaginous embolism)
chronic causes of spinal injury
- degenerative disk disease
- degenerative myelopathy
- cervical stenotic myelopathy (wobblers)
diagnostics for spinal patients
imaging
- radiographs (not ideal to move patients to put plate under)
- CT (3D, can’t see spinal cord damage)
- MRI (gold standard)
CSF tap (possibly)
conservative treatment of spinal patients
- 6 weeks strict rest
- physio
- anti-inflamms
- analgesia
surgical treatment of spinal patients
- hemilaminectomy
- ventral slot
- dorsal laminectomy
- spinal stabilisation
upper motor neuron bladder
- increased urethral resistance
- detrusor and urethral sphincter can contract at same time
- can cause urinary retention
- difficult to manually express
lower motor neuron bladder
- flaccid bladder
- doesn’t contract spontaneously
- bladder continues to fill causing leaking of urine
- bladder muscle is overstretched
- easy to manually express
nursing considerations of spinal patients
- long term patients
- enrichment
- nutrition
- temp control
- padded bedded, turning
- excretion management
- grooming
what does the skull vault contain?
- 80% parenchymal tissue (brain)
- 10% blood
- 10% CSF
intracranial pressure (ICP)
exerted between skull and intracranial tissues
- 5-10mmHg
central perfusion pressure (CPP) equation
CPP= MAP-ICP
cushings reflex
- triggered by severe, acute increase in
ICP
signs: - rise in MAP and reflex bradycardia
- life threatening sign
causes of intracranial disease
- trauma
- inflammatory (menigoencephalitis)
- infectious
- neoplastic
- toxins
- seizures
- anomalous (hydrocephalus)
obtunded mentation
awake but less responsive, will sleep if left
stuporous mentation
only responds to noxious/painful stimuli
circling definition
tight circles, one way
menace response
- move hand towards patients face
- they should blink and retract from the hand
palpebral reflex
- medial canthus, patient should blink
cranial nerve reflex tests
- menace response
- palpebral
- PLR- pupillary light reflex
- gag reflex
- oculocephalic reflex
oculocephalic reflex
- phsyiological nystagmus
- patients eyes are covered and they are moved quickly, eyes should follow
- absence of reflex indicates severe brainstem damage
miosis/miotic pupil definition
constricted
mydriasis/mydriatic pupil definition
dilated
anisocoria pupil definition
asymmetric
pupil clinical signs of deterioration
- pupils go from miotic to mydriatic
- mid-size fixed pupils unresponsive to light
clinical signs of intracranial disease
- altered mentation
- loss of cranial reflexes
- altered respirations
- loss of consciousness
- seizures
- altered posture
what 3 domains does glasgow coma score assess?
- motor activity
- brainstem reflexes
- level of consciousness
lower the score, more severe the deficits
treatment of raised intracranial pressure
- mannitol infusion
- hypertonic saline infusion
mannitol infusion as treatment of raised ICP
- hyperosmolar
- reduces cerebral oedema
- increases CPP and cerebral blood flow
- rapid onset
- duration of action= 1.5-6hrs
- boluses of 0.5-1.5g/kg
- diuretic (isotonic fluids after to maintain vascular vol)
- crystallises at room temp (warm)
hypertonic saline therapy as treatment for raised ICP
- similar osmolarity to mannitol
- improves haemodynamic status
nursing management of raised ICP patients
- recumbancy considerations
- elevate cranial part of body (not just head)
- 30-40 degrees
- no jugular sampling
- ocular care (eye drops)
- mouth checks of intubated patients (4-6hrs)
- nutritional support (4-6hrs if conscious)
hydrocephalus
excessive accumulation of CSF in ventricular system
causes of hydrocephalus
- obstruction to CSF outflow
- decreased absorption of CSF
- increased production of
CSF
clinical signs of hydrocephalus
- enlarged, dome shaped skull
- behavioural changes
- slowness in learning
- loss of coordination
- visual deficits
- seizures
- depressed mentation
management and treatment of hydrocephalus
- medical= prednisolone, omepromazole
- surgical= diverting CSF to another location (ventriculoperitoneal shunt)
meningoencephalitis of unknown origin (MUO)
non infectious inflammatory disorder of CNS
- unable to tell which type in live patient
3 types of meningoencephalitis of unknown origin
- granulomatous ME (GME)
- necrotising (NME)
- necrotising leukoencephalitis (NLE)
clinical signs of meningoencephalitis
- more commonly small dogs, female, older than 6 months
- seizures, tremors, blindness, altered balance, head tilt, typical neurological signs
diagnosing meningoencephalitis
- clinical exam
- blood tests
- MRI of brain
- CSF analysis (inflammatory signs)
management of meningoencephalitis
immunosuppressive drugs:
- steroids
- cyclosporine
- azathioprine
- cytarabine
antiepileptics (if necessary)
nursing care
prognosis of meningoencephalitis
- variable
- patients that show improvement within 3 months have good prognosis
- focal lesions have better prognosis than multifocal lesions
general considerations for nursing neurological patients
- ambulatory vs non ambulatory
- surgical vs non-surgical
- continent vs incontinent
- temperament
- recumbancy
- normal routine
kennel set up for neuro patient
- thick bedding (duvet, mattress)
- incontinence sheets
- use vet bed as top layer to wick away any urine
- pad out sides of kennel with pillows for extra comfort (not for seizure, head trauma patients)
ways to void a bladder
- manual expression
- intermittent catheterisation (twice a day, easier in males)
- in-dwelling catheterisation
risks of overflow incontinence
- urine scalds due to leakage
- risk of UTI’s
bladder expressing
- express every 6-8hrs
- BID initially for indwelling catheter as can cause iatrogenic trauma
- empty indwelling catheter bag 3-4 times daily
decubital ulcer definition
- open skin wound caused by continued pressure of skin on firm surface
- will eventually cause tissue ischemia
- occurs at bony prominences
4 stages of decubital ulcer
- pigmented area
- small lesion
- deeper lesion towards muscle
- intrudes into muscle down to bone
skin care and sore prevention
- chlorexyderm (treats mild urine scalds)
- talcum powder (soaks up moisture)
- cavilon (no sting barrier cream)
- POM-V flamazine (surface thickness sores, under direction of vet)
exercise for neurology patients
- important even if non-ambulatory (sniffing)
- mobilises joints and muscles aiding recovery
- use proper equipment (sling, rear harness, paw covers)
wound management of spinal patients
- cold therapy (15 mins 4X a day for 48-72hrs)
- wrap in towel, not directly on skin
faecal incontinence management
- check skin daily for sores
- nappies shouldn’t be left on for long periods of time to avoid continued contact of faeces and skin
role of physiotherapy in neuro patients
- promote recovery
- prevent further complications
- preserves neuromuscular function in chronic spinal cord damage
- increases survival times for degenerative myelopathy
benefits of physiotherapy
- pain management
- improve range of motion
- reduce muscle contraction
- stimulate nervous system
- improves blood perfusion
- encourages relearning of motor patterns
considerations for physiotherapy
- patient factors (size, temperament, degree of disability)
- client factors (financial, household, expectations)
types of physiotherapy
- massage
- passive range of motion
- assisted exercises
- active exercises
- proprioceptive exercises (placing feet in correct position)
- neuromuscular electrical stimulation
- hot/cold therapy
- hydrotherapy
massage techniques/routine
- effleurage= gentle contact with palm
- petrissage= roll, squeeze, kneads skin and muscle
- percussion= tapping of skin
- vibration= limbs are gently shaken
coupage definition
- respiratory physiotherapy
- important in recumbent, pulmonary disease patients
- loosens secretions, clears airway
- contraindicated with thoracic trauma, fractured ribs, no gag reflex
passive range of motion (PROM) definition
- flexes and extends joints natural range of motion
- monitor for pain
- 3-4 times a day for 10 mins
assisted exercises
- standing, walking, sit-stand, 3 legged standing, weight shifting
proprioceptive exercises
- standing, weaving
- wobble board, uneven surface, over poles
active exercises
- improves strength, promote independence
- lead exercise on steps, ramps
E-stim
- neuromuscular electrical nerve stimulation
- stimulates muscle contraction
- increases tissue perfusion
- slows neurogenic muscle atrophy
benefits of E-stim
- increases muscle strength, range of motion
- enhances function
- reduces pain, oedema, muscle spasm
how E-stim works
- 1 electrode near motor point of muscle, 1 electrode along muscle body
- check for muscle contraction
- adjust pulse intensity
- 10-20 mins a day
