Key points

• A seizure is a transient episode of abnormal, excessive, or synchronous neuronal activity in the brain; epilepsy is the underlying disorder characterized by a tendency to have recurrent unprovoked seizures.
• Most epileptic seizures are self-limiting and stop within 1-2 minutes; prehospital care focuses on protecting the patient from injury, supporting airway, breathing and circulation, and treating prolonged or recurrent seizures.
• Status epilepticus is defined operationally as a seizure lasting ≥5 minutes, or two or more seizures without return to baseline between them, and is a time-critical emergency.
• Always check a blood glucose in any seizing or postictal patient; hypoglycemia is a common, easily reversible mimic or cause of seizure-like activity.
• Never restrain a seizing patient or place anything in their mouth; this increases risk of injury and aspiration and does not prevent tongue biting.

Seizure phases

Seizures are often described in four phases, but not every patient experiences all of them and durations vary widely.

1. Prodromal phase

A vague premonitory period that may precede the seizure by hours to days. The patient (or family) may notice:

• Mood changes, irritability, anxiety
• Headache or fatigue
• Difficulty concentrating

The prodrome is not part of the seizure itself; it reflects subclinical changes in cortical excitability, and patients with established epilepsy often recognize their own prodromal pattern.

2. Aural phase

The aura is a focal aware seizure and represents the earliest ictal activity, usually lasting seconds to a couple of minutes, during which consciousness is preserved. Features depend on the cortical region involved:

• Temporal lobe: déjà vu, jamais vu, rising epigastric sensation, fear, olfactory or gustatory hallucinations
• Occipital: visual disturbances, flashing lights, scotoma
• Frontal/motor: focal twitching, posturing
• Parietal: paresthesias (tingling, numbness), distorted body image

Not all generalized seizures have an aura, but when present it can provide a brief warning and allow the patient to move to a safer position.

3. Ictal phase

The ictal phase is the seizure itself, typically 30 seconds to 2 minutes for most generalized convulsive seizures. Presentation varies by seizure type:

4. Postictal phase

The postictal phase is the recovery period after the ictal event ends and may last from minutes to several hours, especially in elderly patients or after prolonged seizures. Expect:

• Decreased level of consciousness, confusion, disorientation
• Headache, myalgias, fatigue
• Amnesia for the event
• Todd's paresis - transient focal weakness, often hemiparesis, lasting up to ~24 hours and easily mistaken for stroke.
• Gradual improvement in GCS; failure to improve should prompt suspicion for ongoing non-convulsive seizure activity or alternative pathology.

Recognition and assessment

Witnessed seizure

Gather a focused history from bystanders while managing ABCs; this information is often lost once the seizure stops.

• Onset: sudden vs gradual, aura, any focal onset (head/eye deviation, unilateral jerking)
• Duration: time the seizure if active; ask for actual observed duration, recognizing that lay estimates are often exaggerated.
• Pattern: tonic-clonic, focal, repeated episodes, or clusters
• Trauma: fall, head strike, tongue bite, other injuries
• History: known epilepsy, last seizure, medication adherence, recent illness, drug or alcohol use, head injury, pregnancy, recent medication changes or missed doses

Differential diagnosis

Many conditions mimic epileptic seizures; consider:

• Syncope with convulsive movements (convulsive syncope) - brief myoclonic jerks during transient cerebral hypoperfusion, typically <15 seconds, rapid orientation, and minimal postictal confusion.
• Psychogenic non-epileptic seizures (PNES) - often prolonged with fluctuating course, asynchronous limb movements, side-to-side head shaking, closed eyes with resistance to opening, and preserved awareness despite bilateral motor activity; treat supportively and avoid unnecessary medications when safely distinguishable.
• Stroke/TIA - persistent focal deficits without clear generalized tonic-clonic activity, or postictal Todd’s paresis mimicking stroke.
• Metabolic/toxic causes - hypoglycemia, hyponatremia, intoxications, and withdrawal states may present with seizure-like events.
• Other mimics - migraine with aura, syncope, vertigo, movement disorders, and rigors.

Interventions

Protect the patient

• Move hazards away from the patient; only move the patient if they are in immediate danger (e.g., roadway, water, stairs).
• Pad under the head with something soft (folded jacket, towel); do not forcibly restrain limbs.
• Loosen tight clothing around the neck.
• Never put anything in the mouth; patients do not swallow their tongue, and bite blocks or objects can cause dental injury, vomiting, and airway obstruction.
• As soon as convulsions stop and it is safe, place the patient in the lateral recovery position to protect the airway from secretions and vomit.

Airway and breathing

During the tonic-clonic phase, brief apnea and cyanosis are common and usually self-limited; attempts to force a BVM mask mid-seizure are often ineffective and may cause harm. Focus on preparation and postictal airway support.

Once convulsions stop:

• Suction oral and nasal secretions as needed.
• Position laterally if tolerated.
• Apply supplemental oxygen, titrated to maintain SpO₂ ≥ 94%.
• Insert NPA if tolerated; consider OPA only if the patient is deeply unresponsive with no gag reflex.
• Assist ventilations with BVM if there is hypoventilation or hypoxia.
• Use capnography where available; persistently low ETCO₂ may reflect sustained hyperventilation, while rising ETCO₂ may signal hypoventilation or fatigue, and trending can help identify occult ongoing seizure activity.

Circulation and glucose

• Obtain a blood glucose on every patient with seizure or postictal altered level of consciousness; treat hypoglycemia if found.
• If within scope, acquire a 3-lead ECG once the patient is stable, as arrhythmogenic conditions (e.g., long QT, Brugada) can present with seizure-like collapse.

Status epilepticus

Status epilepticus (SE) is defined for operational purposes as a seizure lasting ≥5 minutes, or recurrent seizures without recovery to baseline between them. Mortality and neurologic injury increase with duration, so treat early rather than waiting for older 30-minute definitions.

Information on treatment of SE using specific medications is to be added here.

Pediatric considerations

• Febrile seizures (6 months-5 years) are usually brief, generalized, and benign; antipyretics treat the fever but do not abort the seizure.
• A complex febrile seizure (>15 minutes, focal features, or recurrent within 24 hours) warrants closer evaluation and often emergency department assessment.

Transport and disposition

• Transport all patients with a first-time seizure, status epilepticus, persistent altered mental status, suspected eclampsia, seizure associated with significant trauma, or concerning underlying cause (e.g., CNS infection, intracranial hemorrhage).
• Known epileptics with a brief, typical seizure who fully return to baseline and have reliable supports may decline transport, but document assessment thoroughly and provide clear return precautions and follow-up advice.
• Continuously monitor airway, breathing, circulation, and mental status during transport; postictal patients can re-seize and may develop delayed hypoventilation after benzodiazepines.

References

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