23. Seizure Flashcards
History taking seizure
PC:
HoPC:
- before: where were you? dizziness? light-headed? tunneled vision? nausea?, strange feeling? epigastric rising? deja vu? visual or smell disturbance?
- during: memory of during? toung biting? incontinence? duration? movements?
- after: recovery quick or slow? drowsy? weakness afterwards?
MHx:
syncope- Heart disease (arrhythmias) Peripheral neuropathy Drugs (that cause postural hypotension - e.g. diuretics, antipsychotics, antidepressants, antihypertensives)
seizure: recent infections?
space occupying: ever had cancer diagnosis (?mets)
DHx:
adherence if on anti-convulsants
FHx:
SHx:
syncope - Pain, heat, exertion, prolonged standing, emotion
seizure - Alcohol, sleep deprivation, bright lights, infections
Could you be pregnant?sexually active?
COLLATERAL HISTORY
causes of seizures?
Vascular: haemorrhagic stroke
Infectious: meningitis, encephalitis, systemic infection lowering seizure threshold, febrile seizures paeds
Trauma: head injury
Metabolic: Electrolyte disturbances: hyponatraemia, hypernatraemia, hypoglycaemia, hypocalcaemia, hypokalaemia, ammonia (hepatic encephalopathy)
Iatrogenic: tricyclic overdose, alcohol and benzodiazepine withdrawal
Neoplastic: space occupying lesion,
Environment: alcohol, stress, sleep deprivation
Functional: non-epileptic seizure
Pregnancy: eclampsia
what are breakthrough seizures
seizures that occur in known epileptics. These can be caused by poor medication compliance or precipitating factors such as sleep deprivation, alcohol and stress.
complications of prolonged seizures?
Airway:
Hypoxic brain injury due to airway occlusion and aspiration
Develop epilepsy after a prolonged seizure w hypoxic brain injury
Aspiration pneumonia
Injury:
Anterior dislocation of shoulder
Trauma and injury eg falling down stairs
Muscles contracting:
Electrolyte complications- lactic acidosis -
Creatinine kinase as a result of muscle breakdown - raised - rhabdomyolysis - kidney failure
Potassium intracellular so as muscles breakdown it is released - hyperkalaemia
Heart:
Arrhythmias
when should you treat a seizure?
Emergency treatment should be sought or given once a seizure has persisted, or there are serial seizures, for five minutes or more.
what is status epilepticus?
a single seizure lasting >5 minutes, or
>= 2 seizures within a 5-minute period without the person returning to normal between them
what should you consider as the cause for seizures first?
Rule out hypoxia and hypoglycemia before considering other causes
Assessment of prolonged seizure
ABCDE
Airway
Nasopharyngeal airway works well
Suction if anything visible
Recovery position if at risk of aspiration
Breathing
Oxygen
ABG may show metabolic acidosis (lactic acid from muscle contraction)
Circulation
At risk of
ECG monitor as at risk of CA and because of drugs you will use
Disability
GCS
Blood glucose!!
Exposure
Check for head trauma
PPting factors: acute illness, possible toxic exposure, trauma, recent heavy alcohol intake or cessation of chronic drinking, change in antiseizure medications
invetsigations
ABG (For acute prolonged seizures looking for hypoxia and hypercapnia)
Blood tests: FBC, U&Es (including serum calcium, magnesium and phosphate) LFTs, glucose
Urine test: urine toxicology screen
Imaging: CT Head
who should undergo RSI - rapid sequence endotracheal intubation and mechanical ventilation?
●Unprotected or unmaintainable airway
●Apnea or inadequate ventilation
●Hypoxemia
●Status epilepticus lasting ≥30 minutes
●Need to protect airway for urgent brain imaging (eg, in a patient with preceding trauma or signs of basilar territory stroke)
prolonged seizure treatment algorithim
- Benzodiazepine dose 1
- If still fitting after 10 mins, benzodiazepine dose
- Phenytoin or levetiracetam (keppra)or valproate
- If beyond 30 mins - Refractory status epilepticus (RSE) is defined as status epilepticus that continues despite treatment with benzodiazepines and one antiepileptic drug. - rapid sequence endotracheal intubation and mechanical ventilation - thiopentone in fitting pt (has anti-seizure properties)
what benzodiazepine should you use in prolonged seizure algorithim in diff settings?
Pre-hospital buccal midazolam 10mg may be given by carers etc
Hospital setting w/o IV access - give rectal diazepam 10mg
Hospital setting w IV access - give 4mg IV lorazepam
benzodiazepine SE/risks
CNS depressive affects
resp depression
antidote benzodiazepines? works well for?
Flumazenil is antidote (selective competitive antagonist of the gamma-aminobutyric acid (GABA) receptor)
- Flumazenil may be effective in reversing the sedation that occurs in a benzodiazepine overdose, but its effects on reversal of depressed breathing is less predictable.
Phenytoin considerations and dosing
20mg/kg loading dose
then 100mg every 6-8 hrs
DO NOT GIVE LOADING DOSE IF ALREADY ON PHENYTOIN - THEORETICAL RISK
It is Contraindicated in:
Second- and third-degree heart block; sino-atrial block; sinus bradycardia; Stokes-Adams syndrome, pregnancy
Ask if pregnant
Ask about medications and risk of CA
ECG monitor
What alternative drugs could you use if phenytoin is contraindicated?
Sodium valproate
levetiracetam (NICE says consider this 1st as less SE etc.)
what induction agent RSI fitting
thiopentone in fitting pt (has anti-seizure properties)
what is hypoglycaemia
Hypoglycemia occurs when glucose concentration falls below the normal fasting glucose level. Generally, this is defined as blood glucose levels below 3.3 mmol/L.
why are episodes of hypoglycaemia common in diabetic patients?
due to the variable response of blood glucose levels to their medications
symptoms of hypoglycaemia at different BG levels?
Blood glucose concentrations <3.3 mmol/L cause autonomic symptoms due to the release of glucagon and adrenaline (average frequency in brackets):
Sweating (66%)
Shaking (55%)
Hunger (44%)
Anxiety (27%)
Nausea (13%)
Blood glucose concentrations below <2.8 mmol/L cause neuroglycopenic symptoms due to inadequate glucose supply to the brain:
Weakness (50%)
Vision changes (42%)
Confusion (33%)
Dizziness (26%)
Severe and uncommon features of hypoglycaemia include:
Convulsion
Coma
management of hypoglycaemia
If the patient is alert, a quick-acting carbohydrate may be given (GlucoGel or Dextrogel).
If the patient is unconscious or unable to swallow, subcutaneous or intramuscular injection glucagon may be given.
Alternatively, intravenous 20% glucose solution may be given through a large vein
Presentation of acute alcohol withdrawal
symptoms start at 6-12 hours: tremor, sweating, tachycardia, anxiety
peak incidence of seizures at 36 hours
peak incidence of delirium tremens is at 48-72 hours: coarse tremor, confusion, delusions, auditory and visual hallucinations, fever, tachycardia
delirium tremens is characterised by?
agitation, confusion, paranoia, and visual and auditory hallucinations.
management delirium trmemens/alcohol withdrawal and seizures
alcohol withdrawal:
1. Chlordiazepoxide or diazepam in reducing regimen (long acting benzo)
2. Lorazepam if hepatic failure in reducing regimen
3. Carbamazepine
seizures
1. Lorazepam
delirium tremens
1. Lorazepam oral (fast acting benzo)
2. Lorazepam non-oral or haloperidol
Also give pabrinex if req (thiamine - vitamin b1)
what vitamin is thaimine
B1
typical presentation febrile seizures
typically occur in children between the ages of 6 months and 5 years
around 3% of children will have at least one febrile convulsion
usually occur early in a viral infection as the temperature rises rapidly
seizures are typically brief and generalised tonic/tonic-clonic in nature
management of eclampsia
IV magnesium sulphate
call obs, anaestheist, emergency theatres, neonatal intensivist etc.
typcial history generalised tonic-clonic seizure
There is loss of consciousness and tonic (muscle tensing) and clonic (muscle jerking) movements. Typically the tonic phase comes before the clonic phase. There may be associated tongue biting, incontinence, groaning and irregular breathing.
After the seizure there is a prolonged post-ictal period where the person is confused, drowsy and feels irritable or low.
what is a focal seizure
start in a specific area of the brain
may be impaired awareness or aware
presentation focal seizure
motor or non-motor aura
motor- jacksonian march - spreads from the distal part of the limb toward the ipsilateral face. They involve a progression of the location of the seizure in the brain, which leads to a “march” of the motor presentation of symptoms.
non-motor: déjà vu, jamais vu
another name for focal seizure?
partial seizure
focal seizure temporal lobe features
HEAD
Hallucinations (auditory/gustatory/olfactory), Epigastric rising/Emotional, Automatisms (lip smacking/grabbing/plucking), Deja vu/Dysphasia post-ictal)
focal seizures - frontal lobe features
motor
Head/leg movements, posturing, post-ictal weakness, Jacksonian march
focal seizures - parietal lobe features
sensory
paraesthesia
focal seizures - occipital lobe features
visual
floaters/flashes
Presentation absence seizure
Absence seizures typically happen in children. The patient becomes blank, stares into space and then abruptly returns to normal. During the episode they are unaware of their surroundings and won’t respond. These typically only lasts 10 to 20 seconds. Most patients (more than 90%) stop having absence seizures as they get older.
quick recovery; often many per day
presentation atonic seizures
They are characterised by brief lapses in muscle tone. These don’t usually last more than 3 minutes. They typically begin in childhood. They may be indicative of Lennox-Gastaut syndrome.
presentation myoclonic seizures
sudden brief muscle contractions, like a sudden “jump”. The patient usually remains awake during the episode. They occur in various forms of epilepsy but typically happen in children as part of juvenile myoclonic epilepsy.
presentation non-epileptic seizure
Long duration > 10 minutes
Affective vocalisation
Ictal crying
Ictal eye closure
Side to side movement of head or body
Pelvic thrusting
Fluctuating course
Memory recall
history of trauma and/or mental health problems
EEG absence seizure
3 Hz generalised, symmetrical
presentation infantile spasms
Brief spasms beginning in first few months of life
1. Flexion of head, trunk, limbs → extension of arms (Salaam attack); last 1-2 secs, repeat up to 50 times
2. Progressive mental handicap
usually 2nd to serious neurological abnormality (e.g. TS, encephalitis, birth asphyxia) or may be cryptogenic
poor prognosis
presentation lennox-gestaut syndrome
May be extension of infantile spasms (50% have hx)
onset 1-5 yrs
atypical absences, falls, jerks
90% moderate-severe mental handicap
diet for lennox-gestaut
ketogenic
EEG infantile spasms
hypsarrythmia
EEG lennox-gestaut syndorme
slow spike
presentation benign rolandic epilepsy
paraesthesia (e.g. unilateral face), usually on waking up
presentation juvenile myoclonic epilepsy
Typical onset in the teens, more common in girls
1. Infrequent generalized seizures, often in morning
2. Daytime absences
3. Sudden, shock like myoclonic seizure
Investigation ?post first epileptic seizure
MRI can be used to identify any serious disorder that may have provoked the seizure, such as a brain tumour or arteriovenous malformation (a blood vessel abnormality).
electroencephalogram (EEG)
When do you start treatment for epilepsy
Most neurologists now start antiepileptics following a second epileptic seizure.
unless:
the patient has a neurological deficit
brain imaging shows a structural abnormality
the EEG shows unequivocal epileptic activity
the patient or their family or carers consider the risk of having a further seizure unacceptable
what to consdier when choosing anti-epleptic
- other medications antiepileptics can induce/inhibit the P450 system resulting in varied metabolism of other medications, for example warfarin
- contraception both the effect of the contraceptive on the effectiveness of the anti-epileptic medication and the effect of the anti-epileptic on the effectiveness of the contraceptive need to be considered
- pregnancy or wanting to get pregnant
- breastfeeding
Management generalised tonic-clonic seizures
men, girls under 10 unlikely to need in future, women unable to have children
1. sodium valproate
women and girls
1. lamotrigine or levetiracetam
Management focal seizures
- lamotrigine or levetiracetam
- carbamazepine, oxocarbazepine, zonisamide
- lacosamide
management absence seizures
- ethosuximide
- sodium valproate
sodium valproate particularly effective if co-existent tonic-clonic seizures in primary generalised epilepsy
management myoclonic seizures
boys and men, girls under 10 unlikley need in future, women unable to have children
1. sodium valproate
women and girls
1. levetiracetam
management tonic/atonic seizures
boys and men, girls under 10 unlikley need in future, women unable to have children
1. sodium valproate
women and girls
1. lamotrigine
what seizures may carbamazepine exacerbate
absence and myoclonic
risk benefit epilepsy management in pregnancy
The risks of uncontrolled epilepsy during pregnancy generally outweigh the risks of medication to the fetus.
All women thinking about becoming pregnant should be advised to take folic acid 5mg per day well before pregnancy to minimise the risk of neural tube defects. Around 1-2% of newborns born to non-epileptic mothers have congenital defects. This rises to 3-4% if the mother takes antiepileptic medication.
management of epilepsy in pregnancy
folic acid 5mg per day well before pregnancy
monotherpay - lamotrigine
sodium valproate pregnancy associations
associated with neural tube defects
most common defect - hypospadias
significant risk of neurodevelopmental delay in children following maternal use of sodium valproate.
phenytoin pregnancy associations
cleft palate
breastfeeding anti-epileptics
Breast feeding is generally considered safe for mothers taking antiepileptics with the possible exception of the barbiturates
EEG benign ronldanic epilepsy
centro-temporal spikes
management infantile spasms (wests)
prednisolone or vigabatrin
indicators epilepsy > non-epileptic
Tongue biting and raised serum prolactin
DVLA first unprovoked/isolated seizure
6 months off if there are no relevant structural abnormalities on brain imaging and no definite epileptiform activity on EEG.
DVLA established epilepsy or multiple seizures unprovoked
may qualify for a driving licence if they have been free from any seizure for 12 months
if there have been no seizures for 5 years (with medication if necessary) a ’til 70 licence is usually restored
DVLA withdrawal of epilepsy medication
should not drive whilst anti-epilepsy medication is being withdrawn and for 6 months after the last dose
DVLA syncope
simple faint: no restriction
single episode, explained and treated: 4 weeks off
single episode, unexplained: 6 months off
two or more episodes: 12 months off
