Nervous System Flashcards
What is cerebral palsy?
A group of disorders in which there is developmental delay and disorder of posture and movement resulting from a non-progressive, permanent, fixed cerebral lesion in developing/immature brain
May or may not also present with other neurological symptoms eg learning difficulties / epilepsy
How common is cerebral palsy?
Most common motor impairment in children
1/500
What proportion of cerebral palsy are caused by damage to the immature brain antenatally, perinatally and postnatally?
Antenatal = 80% Perinatal = 10% Postnatal = 10%
What are some antenatal causes of cerebral palsy?
1) Maternal infection = TORCH
2) Radiation exposure
3) Intraventricular haemorrhage (IVH)
4) Chorioamnionitis
5) Multiple births eg twins
6) Maternal resp or genitourinary infection
What is TORCH?
Toxoplasmosis Other infections eg syphilis, VZV, parvovirus B19, Listerosis and Coxsackie virus Rubella CMV Herpes simplex
What are some perinatal causes of cerebral palsy?
1) Hypoxic-ischaemic encephalopathy (HIE)
2) Intrapartum trauma
What are some postnatal causes of cerebral palsy in the neonate?
IVH Hyperbilirubinaemia - Kernicterus Hypoglycaemia Cerebral infarct Meconium aspiration Meningitis Encephalitis
What are some postnatal causes of cerebral palsy in the infant?
Hydrocephalus
Hypoglycaemia
CNS infection
What are some postnatal causes of cerebral palsy in the child?
Hypoxic event eg drowning
Head trauma
Lead poisoning
CNS infection
What is the disease progress of cerebral palsy?
Lesion is fixed and non-progressive but the symptoms become worse over time
= “circle on an inflating balloon” as child’s brain grows
What are the three classifications of cerebral palsy based on type of movement disorder?
1) Spastic (80%)
2) Dyskinetic
3) Ataxic
Describe the spastic movement of cerebral palsy
It is caused by damage to what?
Intermittently increased tone and pathological reflexes = stiff and tight muscles
Damage of UMN
What are the varying degrees of spastic movement disorder in cerebral palsy?
Hemiplegia
Diplegia
Quadriplegia
Describe hemiplegic spastic movement in cerebral palsy
Hemiplegia:
- Unilateral arm and leg affected (arm>leg)
- Arm = flexed and pronated
- Leg = cricumducted gate, tiptoe walking, delayed walking
- Moderate developmental delay and seizure risk
Describe diplegic spastic movement in cerebral palsy
Diplegia:
- Mostly lower limbs affected (less arms)
- Commando crawl = dragging legs scissored
- Often normal intellectual development and minimal seizure risk
Describe quadriplegic spastic movement in cerebral palsy
Quadriplegia:
- All four limbs affected
- Increased tone
- Swallowing difficulties
- Significant intellectual delay
Describe the two types of dyskinetic movement of cerebral palsy
It is caused by damage to what?
1) Athetoid = writhing movement
- Often normal intellectual development
2) Dytonic = involuntary movements
- Worse on movement
- Unusual posture
Damage to basal ganglia
Describe the ataxic movement of cerebral palsy
It is caused by damage to what?
Shaky movements, poor balance and sense of positioning
Ataxic gait = wide base, unsteady trunk, jerky movements
Damage to cerebellum
When can the lesion occur in cerebral palsy?
At any point from conception - 3yrs
After 3 yrs = acquired brain injury
How may cerebral palsy present?
1) Delayed milestones
2) Abnormalities of tone eg hypotonia, spaces or dystonia
3) Abnormal motor development eg late head control, rolling, crawling
4) Feeding difficulties
What are the most common delayed milestones in children with cerebral palsy?
1) Not sitting by 8 months
2) Not walking by 18 months
3) Early hand preference before 1 year (should be ambidextrous until 18 months)
Correct for gestational age
What are complications of CP?
Physical
- Muscle spasms and contractions
- Feeding difficulties and nutritional problems
- incontinence
Social
- Problems dressing, ADLs
- Developmental delay
- Hearing / language impairment
MSK
- Scoliosis
- Hip dislocation
- Inc risk of low bone mineral density = inc risk of osteomalacia / osteoporosis
Neuro
- Epilepsy
Other body systems
- Recurrent respiratory infections
- GORD
- Constipation
- UTI
NB many children with CP have preserved cognitive function
What investigations are done for CP?
Diagnosis made clinically
Exclude other causes eg:
- Thyroid studies
- Chromosomal analysis
- CSF etc
What may be given to improve movement in CP?
Mobility aids eg orthotic devices, wheelchairs
Splinting improve ROM eg ankle joints
What may be given to help manage spacisity in CP?
Oral diazepam = useful if rapid effect needed eg pain crisis
Baclofen = sustained long term effect eg continuous discomfort
Baclofen can be given via continuous pump-administered intrathecal Baclofen
What may be given to help manage dystonia eg problems with posture, function or pain?
Trihexyphenidyl
Levodopa
Baclofen
When may botulinum toxin type A be given in CP?
Focal spasticity eg impeding fine motor function / disturbing sleep
Rapid onset spacisity
What professionals involved in MDT approach of CP?
Paeds OT SALT Nutrition Education
What are febrile seizures?
aka febrile fit/convulsion
= Seizures occurring in children aged 6 months - 5 years, associated with fever, without an underlying cause such as a CNS infection or electrolyte imbalance
What two features must be present in order for a classification of a febrile convulsion?
1) Axillary temperature above 37.8 degrees c
2) Clinical hx / examination indicative of febrile seizures
What is the emergency treatment of febrile seizures?
If child is still convulsing or not fully altert:
- Recovery position + ABCDE
- Check blood glucose
- If still seizing >5min = rectal diazepam OR single dose buccal midazolam OR IV lorazepam
Meningococcal disease suspected:
- benpen or cefotaxime
What is a simple febrile seizure?
Generalised tonic-clonic seizures
Last <15mins
Do not recur within 24hrs or within the same febrile illness
= most febrile seizures
What is a complex febrile seizure?
Must have one/more of:
1) Focal features at onset or during seizure
2) Duration >15mins
3) Recurrence within the same febrile illness
= 20% febrile convulsions
What is a febrile status epileptics?
Febrile seizure lasting more than 30 minutes
= 5% febrile convulsions
What are other types of seizures related to acute illness in children?
1) Febrile myoclonic seizures
2) Afebrile convulsions in young children with mild gastroenteritis - clusters of seizures with/without fever over several days in those with gastroenteritis = good prognosis
How common are febrile convulsions?
Common - 2-5% children
What are the most common causes of fever in febrile convulsions? (5)
Most:
1) Viral infections eg URTI
2) OM
3) Tonsillitis
Others:
4) Gastroenteritis
5) Post-immunisation
What are some serious illnesses which need excluding in a febrile child with a seizure?
1) Meningitis and septicaemia
2) UTI
3) LFTI
4) Cerebral malaria
What features of a seizure are important in a seizure hx?
1) Conscious level prior to seizure
2) Duration
3) Focal or generalised
4) Time taken to recover
5) State of child after
CHECK for signs of meningitis or sepsis
What investigations are performed for a febrile convulsion?
Investigate febrile illness rather than seizure, eg:
Bloods: FBC, ESR, glucose, U&Es, coagulation, culture
Urine microscopy/culture
LP
Ddx for febrile convulsion?
Rigors Syncope Breath-holding spells Reflex anoxic seizures Apneoa Postictal fever Epilepsy Hypoglycaemia Encephalitis Afebrile seizures with gastroenteritis
What are reflex anoxic seizures?
A precipitant eg minor bump causes vaguely mediated cardiac asystole lasting many seconds
Child may be pale, floppy and lose consciousness, followed my tonic and clonic movements
What makes a posticltal fever more likely?
Temp >38
Seizure lasts >10min
What is the management of a febrile convulsion?
Monitor for a few hours
Send home if child looks well, parents understand how to treat febrile illness and further seizures and can access medical services easily
Arrange review
What advice should be given to a parent of a child with febrile convulsions?
Give leaflet
Explain what febrile seizures are
How to treat fever at home - remove excess clothing, give fluids, give antipyretics if child uncomfortable
Tepid sponging or cooling not recommended
Check for non-blanching rash, change of alertness, dehydration, fever >5 min - seek medical assistance
Stay with child at night
First aid if child has a fit - position child and do not put anything in their mouth
Call 999 if seizure lasts more than 5 minutes
What is the prognosis of febrile convulsions?
Good
By definition do not recur beyond 5 yrs (30% do)
Intellect not affected, nor is there an inc risk of death
What are some risk factors of recurrence of febrile convulsions? (4)
1) FH
2) Onset <18 months
3) Lower temperatures
4) Shorter duration of fever at onset
What % of children with febrile seizures go on to develop epilepsy?
2-7%
Higher with complicated febrile convulsions
In which age group do breath holding spells mainly occur? How common are they?
Babies and toddlers (<3yr)
Common - approx 2%
What two categories can breath holding spells be split into?
Cyanotic
Pallid
What is a cyanotic breath holding spell?
Event it always precipitated by crying because of pain or temper
Child takes a deep breath, stops breathing, becomes deeply cyanotic and the limbs extend
Prolonged attacks can lead to transient LOC and occasionally jerks of extremities
Absent of postictal phase is key
What is the management of cyanotic breath holding spells?
Reassurance of parents
Parents ignoring is ideal (but cold water on forehead may be helpful)
What is the prognosis of cyanotic breath holding spells?
The attacks are always benign and disappear before the child reaches school age
However, children with this hx have a higher incidence of vasovagal attacks later in life
What is a pallid breath holding spell?
= Reflex atonic seizures
Classically follows a bump on the head or other minor injury which triggers vagal reflex overactivity, causing transient bradycardia and circulatory impairment
How do pallid breath holding spells present?
Child may or may not start to cry, but then turns pale and collapses
There is transient apnoea and limpness, followed by rapid recovery
How can pallid breath holding spells be differentiated from epilepsy?
Typical history and absence of postictal drowsiness
Normal electroencephalogram (EEG)
How are pallid breath holding spells managed?
Reassurance
Disappear spontaneously prior to school age
What is a seizure / convulsion / fit?
Impairment or loss of consciousness, abnormal motor activity, sensory disturbances or autonomic dysfunction
What is epilepsy?
Condition of recurrent fits resulting from paroxysmal involuntary disturbances of brain function, which are unrelated to a fever or an acute cerebral insult
How is epilepsy categorised?
1) Generalised from onset
2) Focal - beginning in a localised or focal area of the brain, but may become generalised resulting in a tonic-clonic fever
Give 5 types of generalised seizure
1) Generalised tonic-clonic seizure - Grand mal
2) Tonic seizure
3) Absence seizures = petit mal
4) Myoclonic seizures
5) Atonic seizures
Give 2 types of focal seizure
1) Focal motor seizure
2) Focal sensory seizure
Give 4 examples of locations of focal seizures
1) Frontal lobe seizures
2) Temporal lobe seizures
3) Parietal lobe seizures
4) Occipital lobe seizures
List some causes of epilepsy in children
1) Idiopathic = majority
2) Lesion disrupting electrical activity in brain (esp those with LD)
3) Cerebral insult eg trauma / infection
Describe a generalised tonic clonic seizure (GTCS)
Tonic stage:
- Start with sudden LOC when child falls to the ground, limbs extend, back arches and breathing stops
- Teeth are tightly clenched and tongue may be bitten
Clonic stage:
- Intermittent jerking movements of limbs and face
- Onset of irregular breathing and often micturition and salivation
- Usually lasts only a few minutes
Followed by postictal depression:
- Child may remain sleepy and disorientated for some time
Describe an absence seizure
Fleeting (5-20s) impairment of consciousness, unassociated with falling or involuntary movements
Child often thought to be daydreaming, seen to stop what they are doing an look vacant before continuing as before
Can affect academic progress if occur frequently
How can an absence seizure be confirmed?
EEG showing characteristic bursts of 3-per-second spike and wave activity
Describe a myoclonic seizure
Shock like jerks resulting in sudden falls
Myoclonic seizures tend to be seen in children with what background?
Children who have evidence of a structural neurological disorder and esp cerebral degenerative disorders
What is west syndrome?
Infantile spasms
What are infantile spasms?
Form of myoclonic epilepsy but considered separately as they have a particularly poor prognosis
What is the age of onset of infantile spasms?
3-8 months
Describe what happens in infantile spasms
Typical flexion spasms (‘jack-knife’ or ‘salaam spasms’) lasting a few seconds and occurring in clusters lasting up to half an hour
Often occur from waking from sleep
What may be in the history of a child with infantile spasms?
Potentially a hx of perinatal complications eg asphyxia or meningitis
Development prior may be normal or delayed, but following onset there generally is a regression of developmental skills and prognosis is poor
What do investigations reveal in infantile spasms?
EEG shows characteristic ‘hypsarrhythmic’ (chaotic) pattern
Describe a focal seizure
Usually consists of twitching or jerking of one side of the face, an arm or a leg = focal motor seizures
Sometimes can manifest as a strange sensation eg tingling in one part of the body = focal sensory seizures
Consciousness is usually retained or only slightly impaired
Child may experience temporary weakness of involved part of body after an attack
What is a Jacksonian march?
Sometimes occurs in focal seizures - jerking can start in one part of the body and spread
What is a secondarily generalised seizure?
A focal seizure that progresses into a full blown tonic-clonic attack
Describe a temporal lobe seizure
HEADD Hallucinations Epigastric rising + emotional Automatisms = lip smacking / grabbing / plucking Deja vu + dysphasia post ictal
Postictal phase present
How is a temporal lobe seizure diagnosed?
Careful description of attack
EEG showing discharges arising from the temporal lobe
What % of children with epilepsy have LD?
70%
How is epilepsy diagnosed?
Clinical based on history >1 attack Physical examination for neurogical signs EEG MRI
When is EEG helpful in epilepsy?
Characteristic patterns for absence seizures and infantile spasms
Otherwise only diagnostic if EEG obtained during an attack (unlikely)
Use with caution:
- 5% normal children have abnormal EEG
- 40-50% children with epilepsy have normal EEGs
24hrly EEG can be helpful if daily / nightly episodes
When is an MRI helpful in epilepsy?
Indicated in children with:
- Focal neurological deficits
- Focal EEG changes
- Focal or intractable seizures
To exclude focal lesions eg brain tumour or evidence of encephalitis
(CT if acute brain breed suspected)
What is the drug of first choice for GTCS?
Carbamazepine
Valproate
Lamotrigine
What is the drug of first choice for absence seizures?
Ethosuxamide
Lamotrigine
Valproate
What is the drug of first choice for myoclonic seizures?
Valproate
What is the drug of first choice for focal seizures?
Carbamazepine
Lamotrigine
What is the drug of first choice for infantile spasms?
Vigabatrin
Which anti-epileptic drug has these side effects:
- Vomiting
- Anorexia
- Lethargy
- Hair loss
- Hepatotoxicity?
Valproate
Which anti-epileptic drug has these side effects:
- Abdo discomfort
- Skin rash
- Liver dysfunction
- Leucopenia?
Ethosuximide
Which anti-epileptic drug has these side effects:
- Drowsiness
- Irritability
- Behavioural abnormalities
- Excessive salivation?
Clonazepam
Which anti-epileptic drug has these side effects:
- Dizziness
- Drowsiness
- Diplopia
- Liver dysfunction
- Anaemia
- Leucopenia?
Carbamazepine
Which antiepileptic is teratogenic?
Valproate
What are some important rules for prescribing anti-epileptics?
- Start at lowest dose of therapeutic range
- Gradually increase dose once drug has reached a steady-state of plasma level (about 5 times the drug half life)
- 2nd drug added if 1st drug ineffective at max therapeutic plasma level
- 1st drug should be gradually decreased unless it was partially effective, in which case it can be continued
- Drugs should be given at intervals no longer than one half life
- Drugs with sedative effects given at bedtime, or coincide with seizure pattern if there is one
What advice should be given to a child with epilepsy?
Restriction of physical activity is unnecessary, except child should be attended by a responsible adult while bathing and swimming
Avoid cycling in traffic and climbing high gymnastic equipment
Can only drive if fit free for 1 year
What is the management of an acute fit?
Acute GTCS = put in recovery positioned
- Terminated by giving buccal midazolam or rectal diazepam (parents instructed on how to do this)
- Only give IV drugs in hospital where there are facilities in case child has respiratory arrested
Other types of fit do not require emergency treatment
What is status epilepticus?
Prolonged convulsion lasting >30 mins, or a series of shorter convulsions with failure to regain consciousness between them
What is the management of status epilepticus?
Maintain airway
Give oxygen
Check blood glucose
If PR diazepam has been given, IV lorazepam should be given
PR paraldehyde or IV phenytoin can be tried
If all these have failed, anaethetist should be called and child should undergo rapid sequence induction of anaesthesia with thiopental
Any child with prolonged seizures - monitor carefully in ICU
What instructions should be given to a parent on how to give rectal diazepam?
Rectal diazepam comes in dispenser that is easily dispensed into a child’s rectum
- Put child in knee-chest position lying on side
- Remove cap from rectal diazepam dispenser
- Insert nozzle gently through anus up to the hilt of its spout
- Squeeze contents slowly (2-3mins) into anus
- Remove applicator, lie child in recovery position and stay with them
- May make child sleepy for several hours
What instructions should be given to a parent on how to give buccal midazolam?
More acceptable to parents / public places
- Given as a liquid into the side of the mouth between gums and cheeks
- Absorbed quickly into bloodstream
- Given slowly using a plastic syringe or else the child may choke
- If possible half the dose and give one to each cheek
- Watch carefully for signs of reduced breathing
What is the prognosis of idiopathic generalised seizures?
Good - more than 70% grow out of the condition during childhood
Therapy discontinued if fit free for 2 years
What are some provocative factors for seizures? (3)
Sleep deprivation
Flashing lights
Alcohol withdrawal
What is a prodrome?
Uncommon - may occur hours/days before seizure
Change in mood / behaviour noted by others
What is a partial seizure?
Same as focal - limited to one area of brain
“simple” = consciousness not impaired
“complex” = consciousness impaired
What is an aura?
Part of seizure that precedes other manifestations eg smell, visual, deja vu. Seen in focal seizures
Esp in temporal lobe seizure
What is an atonic seizure?
= akinetic
Brief, sudden hypotonia associated with falls without LOC
Describe the postictal phase
Headache Confusion Tiredness Drowsiness Amnesia Myalgia Todd's palsy = after focal seizure in motor cortex Dysphagia = after focal seizure in temporal lobe
