Paeds: Epilepsy (DrClarke) Management Flashcards
Seizure
- Clear surrounding area
- Put into recovery position once it is over
- Pbserve for signs of breathing, aspiration, injury
Seizure
- if not confused or injured, no immediate action required Seek medical attention -> Investigation
- If confused/injured: wait with them and reassure them; do not attempt to give fluids/food/drug
- Call ambulance
Seizure
- If they recover from seizures: wait with them until fully recovered, may be worth noting any triggers, patterns etc, ? Consider meds review
- If they don’t: Medical emergency
Seizure >5-10 minutes: Immediate treatment
Treat and investigate source.
MEDICAL EMERGENCY:
-Immediate ->resuscitate measures ABC: airway maintained, oxygen given
- Control of seizure-anticonvulsant medication given.
- Identification of underlying cause - ?hypoglycaemia, electrolyte/cardiac/biochemical monitoring
Medical management 4 stages
- Premonitory phase
- Early status
- Established status
- Refractory status
Premonitory phase
Diazepam (10-20mg iv or rectally) - can be repeated once 15 mins later if status still dangerous OR iv bolus clonazepam (1-2mg)
Early status
- Lorazepam bolus (4mg iv) - repeat once if necessary, after 10 mins
Established status
Phenobarbitone bolus (10mg/kg 100mg/min) and/or phenytoin infusion (15mg/kg 50mg/min-ECG monitoring) - small risk of respiratory depression but can help obtain control
Refractory status
- If seizures continue or >30 mins despite Rx then general anaesthesia is given (thiopentone iv bolus then infusion) - artificial ventilation is likely to be necessary - the anaesthetic dose shouldn’t be tapered until >12 hrs after last seizure - EEG monitoring must be done as ventilated pt will be paralysed with muscle relaxants so may not have observable seizures
Long term management
Anti-epileptic drugs (AEDs) - generally after 2ndry seizure
- Monotherapy where possible
- review medication: aim to use minimum dose to maintain control and ideally seizure-free
- It may be possible for patients to come off medication (epilepsy remits in 70%) - obviously they need to have been well-controlled and seizure free for some time
- Important to consider the implications for the patient - depends on individual, their lifestyle, needs etc. i.e. someone who relies on driving may not wish to risk losing their license etc.
3 basic mechanisms for the action of anti-epileptic drugs:
- Suppression of sodium influx
- Suppression of calcium influx
- Potentiation of gamma-aminobutyric Acid (GABA)
Suppression of sodium influx process
The AED binds to sodium channels when they are in the inactive state, thus prolonging the inactive state ↓ ability of neurons to fire at high frequency. Seizures that depend on high frequency discharge are therefore suppressed.
Examples of drugs that suppresses of sodium influx and which seizures they are used in
Carbamazepine, phenytoin & lamotrigine exert their main action in this way & are effective in limiting the spread of a discharge from a focusRx of partial & 2o generalised seizures.
SUPPRESSION OF CALCIUM INFLUX.
The AED acts by inhibiting influx of calcium ions through T-type Ca channels. These calcium channels generate T-currents which usually play a minimal role in action potential generation, but in some neurons in the hypothalamus, T-currents cause action potentials. Absence seizures are caused by ↑ firing of hypothalamic neurons
examples of drugs that suppress calcium infux
this mechanism are preferred for absence seizures. Sodium valproate & ethosuximide act in this way.
POTENTIATION OF GAMMA-AMINOBUTYRIC ACID (GABA).
GABA is an inhibitory neurotransmitter that is widely distributed in the brain & causes a general ↓ in neuronal excitation drug examples: - Barbiturates e.g. phenobarbital - gabapentin - vigabatrin - Benzodiazepines e.g. diazepam
