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| STATUS EPILEPTICUS
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Dr Swati Joshi
B J Wadia Hospital for Children,
Mumbai.
Status epilepticus (SE) is a neurologic emergency associated with significant mortality and morbidity.
Definition : Conventionally defined as " prolonged seizure activity lasting longer than 30 min or series of seizures without recovery of consciousness in the interim".
The term refractory SE is used when there is failure to respond to first line drugs and seizures persist for more than 60 minutes.
Early recognition of SEis of utmost importance because longer the SE, the more difficult the control and more the risk of neurologic sequelae. Therefore, SE should be considered and treatment initiated when patient presents in emergency with continuous seizures or series of seizures without recovery of consciousness lasting 10 or even 5 min.
Incidence : SE is more common in children (more often in less than 3 yr olds) than adults with frequency of around 3.7% .
Classification : Any seizure type can present as SE.Generalised tonic clonic is the most common form and also the one with highest mortality and morbidity.
International classification is as follows ;
Convulsive (generalized) SE ;
- Tonic clonic
- Tonic
- Clonic
- Myoclonic
Nonconvulsive
-Absence status
Partial SE
- -Simple partial SE ; epilepsia partialis continua/ other types
- -complex partial status
Unilateral SE – hemiclonic status, hemiconvulsion hemiplegia syndrome.
Etiology of SE :
There are three main situations in which SE can present :
- Acute situation related :
CNS infections – meningitis, encephalitis
Acute anoxic insult
Metabolic- hypoglycemia, inborn errors of metabolism (IEM), Reye syndrome
Electrolyte imbalance
CNS trauma/ haemorrhage/tumors
Drugs, intoxications, poisoning
Hypoxic ischemic encephalopathy and IEM in newborn period
- First unprovoked seizure presenting as SE – most commonly febrile status
- SE in patients with epilepsies – epileptics on irregular treatment, sleep deprivation, intercurrent infections and symptomatic epilepsies are more prone to developing SE.
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Investigations :
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Basic investigations to be carried out in all cases of SE irrespective of etiology include blood sugar,
serum electrolytes
blood gases , blood urea
complete blood count
serum Ca and Mg in neonates.
Certain other investigations may be required depending on individual situation:
Lumbar puncture
CT/MRI
EEG
Serum anticonvulsant levels
Liver function tests, serum ammonia
Blood cultures
Toxicology screen.
Role of EEG : EEG is useful to recognise SE in paralyzed patients, nonconvulsive SE and in neonates. It is also of use in refractory SE which requires to be treated with midazolam infusion or general anaesthetics.
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MANAGEMENT :
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Goals of treatment ;
- To stop seizures
- Treatment of complications
- Treatment of underlying etiology
Seizure control should be achieved rapidly and effectively since duration of SE is a vital determinant in the response to treatment, mortality and neurologic sequelae. Thus, SE is divided into early stage (0-30 min), established (30-60 min) and late stages (more than 60 min).
Team approach (pediatric neurologist, anaesthetist and critical care staff) along with predetermined protocol management gives best results.
There are no standard internationally/nationally accepted protocols but the following flow chart gives the practical approach to managing a child with SE.
On admission in emergency :
- Diagnose SE (continuous seizure s for more than 5- 10min )
- Assess Airway/Breathing/Circulation, start O2 by nasal catheter
- Position, suction, oral airway without force
- IV/IO access – dextrostix/ s. electrolytes/ ABG
- Rapid evaluation for etiology
- Monitors – pulse oximeter, ECG.
- If dextrostix low or unavailable – Inj 10% dextrose 4ml/kg followed by
- Inj Lorazepam – 0.1mg/kg at 2mg/min
OR
Inj Diazepam - 0.2mg/kg (max 10mg) at 5 mg/min
(can be repeated twice if sz do not stop after 5 min of inj )
- Sz continue – Inj Phenytoin 20 mg/kg (or fosphenytoin, newer derivative, less adverse effects) at 1 mg/kg/min with monitoring of BP, HR , RR ( use normal saline flush, no glucose/Ca )
- Szs continue – consider intubation , inj Phenobarbitone 20mg/kg at not more than 100mg/min
- Sz continue – Repeat inj phenobarb 10mg/kg
- Most seizures stop with above treatment.
- No control with above measures, treat as refractory SE
- Consider intubation and artificial ventilation & EEG monitoring
- Treatment of complications-acidosis, shock, hyperthermia.
- IV Midazolam – Bolus 0.2 mg/kg over 10 min followed by continuous infusion at 0.1 to 2 mg/kg/hour. End point of treatment is suppression of ictal discharges or burst suppression pattern on EEG if available or cessation of clinical seizures activity. Continue infusion for atleast 12 hours and then taper. Watch for Hypotension, if present treat with IV fluids & low dose dopamine.
OR
IV Diazepam infusion
- pentobarbital coma – load with 20-30 mg/kg & then 0.2-0.5 mg/kg/min infusion. Hypotension and respiratory depression more with this than midazolam, therefore latter is preferred.
- Other options -- Lidocaine, isofluorane etc.
Other options if IV access not available,
IO (intraosseous)- all drugs that are given IV can be given in the same doses,
IM (intramuscular)– Fosphenytoin, midazolam
PR(per-rectal)- diazepam(0.5-1mg/kg), lorezepam(0.1-0.4mg/kg),valproate (20mg/kg).
Prognosis : Prognosis is better in children than adults especially in the absence of acute CNS insult or chronic neuroprogressive disease. Mortality and morbidity have improved greatly with optimal seizure management.
Febrile and idiopathic SE have the least morbidity.
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Last created on 6-11-2000
Last updated on 01-07-2006
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