Diagnosis:
Clinical supported by EEG
Clinical features:
This is an emergency & should be treated as soon as recognised, before EEG or tests
A seizure or multiple seizures without regaining consciousness in between lasting >10 min
Findings on Investigations:
EEG: there is a sequence of EEG findings.
1 discrete seizures
2 merging seizures with waxing and waning amplitude and frequency of EEG rhythms
3 continuous ictal activity
4 continuous ictal activity punctuated by low voltage ‘flat periods’
5 periodic epileptiform discharges PED on a ‘flat’ background
Emergency Treatment:
ABC:
- Secure airway as necessary
- Oxygen
Anticonvulsants: if > 10 minutes
- Lorazepam 0.1mg/kg IV X1 dose favoured over diazepam to interrupt seizures. [VA Cooperative study]
- Followed by:
- Fosphenytoin Or Phenytoin PHT 18-20mg/kg IV, aim for level= 20
- If contraindications or partial status epilepticus, consider: sodium Valproate VPA 25-40mg/Kg IV.
If seizures persist:
- Propofol 2 mg/kg bolus, followed by infusion
- Midazolam 0.2 mg/kg bolus IV, 0.1-0.4 mg/kg/hr infusion.(0.75 -11 mcg/kg/min)
- Some physicians consider Phenobarbital PB 20mg/kg IV X 1 dose, aim for level= 40-60.
For refractory status epilepticus in spite of above measures, consider risk vs. benefit of:
- Pentobarbital 20 mg/kg bolus, 1-3 mg/kg/hr infusion
- Thiopentone/thiopental 2-3 mg/kg mg bolus, 3-5 mg/kg/hr infusion
Monitor EEG continuously: aim for burst suppression
Monitor vitals & O2 saturation, alertness
Set up intravenous access
Hyperthermia:
- Cooling blanket
Treat hypoglycemia +/-thiamine
Further investigations to consider:
Venous blood:
Blood glucose, U&E, Ca++ +PO3–, FBC, ESR, LFTs, antiepileptics levels
toxicology
ABG
ECG
Calculate serum osmolality
CXR: aspiration
Urine toxicology
Consider induction of motor paralysis
Lactic acidosis should not be treated, exclude infection
If >5 minutes intubate & ventilate
EEG monitoring if refractory status i.e. 30-90 minutes
ECG
Calculate serum osmolality
CT head
EEG monitoring
LP
MRI & repeated MRI
Consider:
- Blood Mitochondrial DNA analysis: Common deletion, POLG mutations
- Muscle biopsy: mitochondrial disease
- Brain biopsy
- CT thorax, abdomen, pelvis: paraneoplastic syndrome
- Paraneoplastic antibodies