Convulsive status epilepticus — recognition, definition and staged management viva

Interpretation

The examiner describes a patient who has been convulsing continuously for 12 minutes in the ED and asks: "Is this status epilepticus, why does timing matter, and walk me through your management step by step."

• Definition (ILAE 2015): status epilepticus is a continuous seizure lasting longer than the time point t1, or recurrent seizures without recovery to baseline between them. For generalised convulsive SE, t1 = 5 minutes (treatment threshold) and t2 = 30 minutes (risk of long-term neuronal injury).^[1]
• Why treat at 5 minutes, not 30: seizure-terminating mechanisms fail progressively. With ongoing seizure, GABA-A receptors are internalised (loss of inhibition) and NMDA/AMPA glutamate receptors are recruited and upregulated (rising excitation) — a phenomenon called time-dependent pharmacoresistance. Benzodiazepines therefore lose efficacy the longer you wait.^[4]

Key points

The examiner will probe each of these; defend them at viva depth:

1. Definition and classification — t1/t2 for GCSE (5 and 30 min); also focal SE, absence SE, non-convulsive SE; refractory (ongoing after benzodiazepine + one adequate second-line agent) and super-refractory (over 24 h of anaesthesia).^[1][4]
2. Stage 1 (0–5 min) — stabilise: ABCDE, oxygen, IV access, bedside glucose, bloods (incl. AED levels), treat hypoglycaemia; give IV thiamine before glucose in alcohol misuse.^[2]
3. Stage 2 (5–20 min) — emergent benzodiazepine: IV lorazepam 4 mg (0.1 mg/kg), repeat once at 10 min; or IV diazepam 10 mg; or, if no IV, IM midazolam 10 mg (RAMPART: IM midazolam at least as effective and safe as IV lorazepam pre-hospital).^[2][3]
4. Stage 3 (20–40 min) — second-line: IV levetiracetam 60 mg/kg OR fosphenytoin 20 mg PE/kg (cardiac monitoring, max 150 mg PE/min) OR valproate 40 mg/kg. ESETT: all three equally effective (abort ~half of established SE); levetiracetam often preferred — no cardiac monitoring, no interactions.^[2]
5. Stage 4 (refractory) — ICU and anaesthesia: intubate; propofol / midazolam / thiopentone infusion titrated with continuous EEG to burst-suppression for 24–48 h before weaning.^[4]
6. Treat the precipitant — AED non-adherence (commonest), CNS infection, metabolic (Na⁺, Ca²⁺, glucose), stroke, tumour, alcohol withdrawal, hypoxia. Fever → cover empirically (ceftriaxone ± acyclovir), CT then LP once stable.^[4]
7. Don't be fooled by subtle/NCSE — a comatose patient after GCSE may still be seizing electrically: urgent EEG; do not assume the seizure is over when motor activity stops.

High-yield probe answers

• "Why does lorazepam lose effect if you wait?" — GABA-A receptor trafficking/internalisation reduces available receptors; NMDA/AMPA upregulation shifts the balance to excitation → pharmacoresistance.^[4]
• "Which second-line agent and why?" — Levetiracetam (ease, no monitoring, no interactions) — but ESETT found equivalence with fosphenytoin and valproate; in India phenytoin is more available than fosphenytoin.^[2]
• "When is EEG mandatory?" — suspected NCSE, refractory/super-refractory SE, titration of anaesthetic to burst-suppression, and any patient still comatose after GCSE.^[4]
• "Eclamptic seizure?" — IV magnesium sulphate (4 g loading then 1–2 g/h) is first-line, not a benzodiazepine-first approach; coordinate with obstetrics for delivery.
• "Prognosis?" — mortality over 20% overall, 30–40% in refractory SE; aetiology is the strongest determinant (anoxic worst; alcohol-withdrawal/non-adherence best).

References

1. Trinka E, et al. ILAE definition and classification of status epilepticus. Epilepsia 2015.^[1]
2. Glauser T, et al. AES evidence-based guideline: treatment of convulsive SE. Epilepsy Curr 2016.^[2]
3. Silbergleit R, et al. RAMPART — IM vs IV therapy for prehospital SE. N Engl J Med 2012.^[3]
4. Trinka E, Leitinger M. Management of SE, refractory and super-refractory SE. Continuum 2022.^[4]

References4ShowHide

1. [1]Trinka E, Cock H, Hesdorffer D, et al. A definition and classification of status epilepticus — Report of the ILAE Task Force on Classification of Status Epilepticus. Epilepsia, 2015.PMID 26336950
2. [2]Glauser T, Shinnar S, Gloss D, et al. Evidence-Based Guideline: Treatment of Convulsive Status Epilepticus in Children and Adults — American Epilepsy Society. Epilepsy Curr, 2016.PMID 26900382
3. [3]Silbergleit R, Durkalski V, Lowenstein D, et al. Intramuscular versus intravenous therapy for prehospital status epilepticus. N Engl J Med, 2012.PMID 22335736
4. [4]Trinka E, Leitinger M. Management of Status Epilepticus, Refractory Status Epilepticus, and Super-refractory Status Epilepticus. Continuum (Minneap Minn), 2022.PMID 35393970