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This is a clinician-written, evidence-based summary aligned to the USMLE Step 2 CK Content Outline. It is intended for medical students preparing for USMLE Step 2 CK. Management reflects current ACC/AHA, USPSTF, and APA guidelines. Always cross-reference with UpToDate, institutional protocols, and clinical judgment.
The Bottom Line
- Status epilepticus begins operationally at 5 minutes
- First priorities are ABCs, glucose, IV access, and benzodiazepine
- IV lorazepam is first-line; IM midazolam if no IV access
- Second-line therapy includes levetiracetam, fosphenytoin, or valproate
- Refractory status requires ICU, intubation, continuous EEG, and anesthetic infusion
Overview
Status epilepticus is a time-dependent emergency because prolonged seizures become self-sustaining and can cause neuronal injury. Convulsive status is treated clinically without waiting for EEG. Persistent coma after motor activity stops should raise concern for nonconvulsive status.
Epidemiology
Common causes include epilepsy medication nonadherence, alcohol withdrawal, hypoglycemia, hyponatremia, CNS infection, stroke, tumor, traumatic brain injury, eclampsia, and toxic ingestion. Mortality rises with age, prolonged duration, refractory seizures, and acute structural or infectious causes.
Clinical Features
Symptoms
Generalized tonic-clonic activity lasting >=5 minutes
Repeated seizures without recovery of consciousness
Persistent coma or confusion after convulsions stop
Fever, headache, or meningismus suggesting CNS infection
Pregnancy/postpartum hypertension suggesting eclampsia
Signs
Airway compromise, cyanosis, aspiration, or hypoxia
Tachycardia, hypertension, hyperthermia, lactic acidosis
Subtle eyelid twitching or gaze deviation in coma
Focal deficit after seizure may be Todd paralysis or stroke
Signs of trauma or intoxication may be present
Investigations
First-line
Bedside glucoseTreat hypoglycemia immediately; give thiamine first if malnourished when feasible
BMP, calcium, magnesium, CBCIdentify metabolic triggers and complications
Medication levels/toxicologyWhen nonadherence, toxicity, or ingestion suspected
Second-line
CT headAfter stabilization if first seizure, trauma, anticoagulation, focal deficit, cancer, or persistent coma
Lumbar punctureIf meningitis/encephalitis suspected after safe imaging; do not delay antimicrobials
Continuous EEGRefractory status, neuromuscular blockade, persistent altered mental status
Specialist
ICU monitoringFor refractory seizures, ventilation, continuous EEG, and hemodynamic support
MRI brainAfter stabilization if structural or inflammatory cause suspected
1
0-5 minutes
- Call for help, protect airway, oxygen/suction as needed
- Check glucose immediately
- Establish IV access and monitoring
- Treat hyperthermia and trauma supportively
2
5-20 minutes
- IV lorazepam 0.1 mg/kg, repeat once if needed
- IM midazolam if no IV access
- Do not underdose benzodiazepines
- Prepare airway support
3
20-40 minutes
- Load levetiracetam, fosphenytoin, or valproate
- Avoid valproate in pregnancy or severe liver disease
- Avoid phenytoin/fosphenytoin in major heart block if possible
- Treat the precipitating cause
4
Refractory status
- ICU, intubation, continuous EEG
- Midazolam, propofol, or pentobarbital infusion
- Consider autoimmune, infectious, toxic, and structural etiologies
Complications
- Hypoxic brain injury: From prolonged seizure and airway compromise
- Aspiration pneumonia: Common during convulsions
- Rhabdomyolysis: May cause AKI
- Nonconvulsive status: Persistent altered mental status after convulsions
USMLE Step 2 CK Exam Tips
- 1Seizure >=5 minutes = status epilepticus
- 2First antiseizure drug is a benzodiazepine
- 3No IV access = IM midazolam
- 4Second-line: levetiracetam, fosphenytoin, or valproate
- 5Persistent coma after seizure = continuous EEG
- 6Eclampsia seizure = magnesium sulfate
- 7Isoniazid seizure = pyridoxine
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