4. - A seizure is any event involving an abnormal
fi
ring of neurons that causes a sudden
change in behavior characterized by changes in sensory perception or motor activity. It
can sometimes occur in the presence of precipitating factors (provoked seizure).
- The recognition and appropriate management of seizures are critically important,
because prolonged, excessive electrical activity in the brain directly causes neuronal
destruction, especially in the hippocampus.
- Epilepsy is described as the tendency to have unprovoked recurring seizures.
Operationally, an individual who has had two or more unprovoked seizures is said to have
epilepsy.
- If you have one seizure and a 60% chance of a second (such as would be present in a
patient with a single seizure and a stroke), or if you have an epilepsy syndrome, you are
operationally said to have epilepsy.
INTRODUCTION
5. - Seizures can be divided into two major classi
fi
cations based on their origin: Neurogenic seizures & Psychogenic,
or nonepileptic, seizures.
- Neurogenic seizures represent the majority of seizures seen in the ED and result from excessive discharge of
cortical neurons. Neurogenic seizures can be broken down into 2 main subgroups depending on their
manifestation.
- Generalized seizures involve abnormal neuronal activity in both hemispheres of the brain and are accompanied
by a loss of consciousness. They can be further characterized based on the pattern of motor activity, such as
- Tonic: rigid trunk and extremities
- Clonic: symmetrical rhythmic jerking of the trunk and extremities
- Tonic-clonic (grand mal seizure): tonic phase followed by clonic phase
- Atonic: sudden loss of postural tone
- Myoclonic: brief, shock-like muscular contractions
- Absence (petit mal): sudden staring with impaired consciousness.
- Partial (focal) seizures involve neuronal discharge in a localized area of one cerebral hemisphere and are sub-
classi
fi
ed into simple (consciousness is maintained) and complex (impaired level of consciousness).
TYPESOFSEIZURES
6. - Psychogenic, or non-epileptic, seizures (NES) are increasingly common and may be extremely
di
ffi
cult to distinguish from true seizures. Unlike neurogenic seizures, these pseudo-seizures
are not the result of abnormal cortical discharge, and are often associated with major stress or
emotional trauma.
- Status epilepticus (SE) is present when patients have more than 30 minutes of continuous
seizure activity or have 2 or more sequential seizures without full recovery of consciousness in
between.
- SE is the initial presentation of a seizure disorder in approximately one-third of cases. The
most common cause of SE is discontinuation of anticonvulsant medications.
- The catecholamine surge that accompanies SE can cause tachycardia, hypertension,
hypotension, cardiac arrhythmias, respiratory failure, hyperglycemia, acidosis, and
rhabdomyolysis.
- Nonconvulsive SE can also occur and must be ruled out in any patient who does not regain
consciousness within 20 to 30 minutes of cessation of a single generalized seizure and should
be considered in any patient with unexplained confusion or coma.
TYPESOFSEIZURES
7. - For patients with known seizure
disorder, the most likely cause is
sub-therapeutic levels of anti-
epileptic medications, which usually
occur for 1 of the following reasons:
- Medical noncompliance
- Systemic derangement that may
disrupt absorption, distribution,
and metabolism of medication
(infection)
- For patients presenting with new-
onset seizure disorder, the list of
possible causes is long and can be
summarized using VITAMINS
mnemonic.
ETIOLOGY
10. - History is essential in the evaluation of a seizure patient, especially in a
fi
rst-time seizure.
- The goals of the history are to characterize the event as a seizure and rule out alternative
diagnoses, determine whether similar events have happened in the past, and evaluate for
underlying risk factors for seizures in the past medical history, family history, and medications.
- Description of the event — An accurate description of the seizure may be di
ffi
cult to obtain
from the patient and witnesses; it is usually necessary to ask pointed questions about the
circumstances leading up to the seizure, the ictal behaviors, and the postictal state.
- A key element in the history is whether a particular environmental or physiologic precipitant
or trigger immediately preceded the seizure. Triggers include (but are not limited to) strong
emotions, intense exercise, loud music, and
fl
ashing lights.
- Associated symptoms with the seizure should also be addressed to help direct work-up and
management. For example, a headache prior to the seizure is concerning for intracranial
hemorrhage, while a fever and/or general malaise in a patient who presents with a seizure is
worrisome for infectious causes.
HISTORY
11. - Patients presenting to the ED with seizure require a thorough physical examination.
- Neurologic examination (most important) can revel focal neurologic
fi
ndings which may
indicate a focal cerebral lesion (e.g., tumor, abscess, or cerebral contusion) or focal paresis
after seizure (Todd paralysis). Evaluation of the cranial nerves and the fundi can reveal
increased intracranial pressure.
- Hyperre
fl
exia and extensor plantar responses are indicative of a recent seizure but should
resolve during the postictal period.
- Examine for secondary injuries. A complete head-to-toe examination may reveal trauma from
the seizure. Physical
fi
ndings associated with seizures include tongue biting, bowel or
bladder incontinence, and a postictal state of confusion or somnolence.
- Cardiopulmonary examination should include auscultation for heart murmurs or an irregular
rhythm suggesting an embolic or syncopal event.
- Although rare, extremity fractures or dislocations are commonly missed when they do occur
and should be ruled out by a thorough musculoskeletal examination.
PHYSICALEXAMINATION
12. - Laboratory studies in patients with
fi
rst-time seizures include glucose, serum electrolytes such
as sodium, calcium, and magnesium, assessment of renal function, hematology studies such as a
complete blood cell count, and drug or toxicology screen. Women of childbearing age also
require a pregnancy test.
- Serum lactate can be helpful in patients with unwitnessed transient loss of consciousness or
impaired consciousness, as an elevated lactate level within the
fi
rst two hours after onset of
the event suggests the cause was a generalized seizure rather than syncope or a
psychogenic nonepileptic seizure.
- Elevated serum prolactin may be useful in di
ff
erentiating generalized tonic-clonic and focal
seizures from psychogenic nonepileptic seizures in adults and older children. However, it has
limited utility as a diagnostic test for epileptic seizures and is not recommended as part of the
routine evaluation
- Electrocardiogram (ECG) should be performed in all patients with loss of consciousness, as
cardiogenic syncope can manifest as a secondary hypoxic seizure. The purpose of the ECG is to
identify features that may suggest cardiac arrhythmia as a cause of syncope, such as acquired or
congenital long QT syndromes.
DIAGNOSTICWORKUP
13. - Additional testing in patients with a
fi
rst seizure includes neuroimaging in all patients and
electroencephalogram (EEG) and lumbar puncture in selected patients. The urgency with which to obtain
testing depends on the clinical history, examination, and suspicion for an underlying structural cause for
seizure.
- Lumbar puncture is an essential part of the workup if clinical presentation is suggestive of an infectious
process.
- Neuroimaging studies should be performed when a clear etiology to the seizure is not identi
fi
ed or
whenever an acute intracranial process is suspected. American College of Emergency Physicians
(ACEP) guidelines recommend a head CT be performed in patients with a history of recent head trauma,
persistent altered mental status or headache, fever, malignancy, immunocompromised status,
anticoagulation, or in patients who have a new focal de
fi
cit, are over 40, or have a partial-onset seizure.
- Use of the EEG is uncommon in the ED evaluation of
fi
rst-time seizure except in the assessment of
nonconvulsive status epilepticus, or to establish status epilepticus in a patient who has been given long-
acting paralytic agents.
- In patients who have returned to baseline, outpatient EEG is appropriate and may be more
representative of a patient’s underlying risk for seizure recurrence than EEG performed immediately,
which may be confounded by medication e
ff
ects and acute postictal changes.
ADDITIONALTESTING
15. - (a) ABCs (Intubation, oxygenation, ventilation, IVF)
- Aggressive airway protection is critical as seizure patients have decreased gag re
fl
exes
and are at risk for aspiration. Positioning the patient on their side with frequent
suctioning, if necessary, will lower the risk for aspiration.
- Patients who continue to seize despite therapy or those unable to protect their airway
with conservative measures require intubation.
- (b) bedside glucose analysis
- (c) pulse oximetry
- (d) cardiac monitoring
- (d) anticonvulsant therapy if seizure activity continues at time of evaluation.
- Most seizures remit spontaneously within two minutes and rapid administration of a
benzodiazepine or anti-seizure medication is not required.
INITIALSTABILIZATION
16. - First-line therapy for active seizures (including SE) are parenteral benzodiazepines which
are e
ff
ective in terminating seizures in 75% to 90% of patients. They suppress seizure
activity by directly enhancing GABA (gamma-aminobutyric acid)-related neuronal inhibition.
- Lorazepam (0.1 mg/kg given at 2 mg/min) and diazepam (0.2 mg/kg IV given at 5 mg/
min) are equally e
ff
ective at terminating the initial seizure, while lorazepam is superior
for preventing recurrence of the seizure.
- Options for patients without IV access include IM midazolam or lorazepam (midazolam
is probably the best option) in addition to rectal diazepam.
- Patients in SE who require intubation are ideally induced with a benzodiazepine,
serving to both sedate and to abate the seizure. If the patient requires paralysis for
management purposes, it cannot be assumed that the patient’s seizure has been
terminated. In this situation, anticonvulsant therapy should be continued and EEG
monitoring of the patient should be arranged.
PHARMACOLOGICTHERAPY-ABORTIVE
17. - Second-line agents for abortive therapy include phenytoin or fosphenytoin. Phenytoin
does not directly suppress electrical activity at the seizure focus but rather slows recovery
of voltage-activated sodium channels and thus suppresses neuronal recruitment.
- The total oral dose of phenytoin is about 20 mg/kg with a maximum of 400 mg every 2
hours. It can also be given via slow IV administration up to 18 mg/ kg. The rate can be
no greater than 50 mg/min to avoid hypotension and cardiac dysrhythmias associated
with its propylene glycol diluent.
- Cerebellar
fi
ndings, such as nystagmus and ataxia, are the most common neurological
side e
ff
ects.
- Phenobarbital,CNS depressant, directly suppresses cortical electrical activity and is often
used after benzodiazepines and phenytoin have failed.
- Additional agents to be considered for abortive seizure therapy include propofol,
barbiturates (other than phenobarbital), and inhaled anesthetics such as iso
fl
urane.
PHARMACOLOGICTHERAPY-ABORTIVE
18.
19. - Cocaine is one of the most frequent causes of drug-induced seizures. Approximately 15% of cocaine
users will experience a drug-induced seizure. Seizures caused by cocaine are a result of a
combination of a lowered seizure threshold and hyper-sympathetic state.
- They are often associated with hyperthermia and high lactate levels. These seizures are usually
self-limited, but in cases of status epilepticus, should be treated with high doses of
benzodiazepines.
- Tricyclic antidepressants cause seizures as a consequence of their anti-cholinergic properties. In
addition to standard seizure therapy, patients with status epilepticus secondary to tricyclic overdose
should be treated with sodium bicarbonate in an e
ff
ort to obtain a blood pH of approximately 7.5.
- This will decrease the free form of the drug in the patient’s CNS as well as mitigate the drug’s
sodium channel–blocking e
ff
ect on the heart.
- Isoniazid-induced seizures are associated with a high mortality rate and typically occur within 120
minutes of an acute overdose.
- Treatment of seizures secondary to isoniazid toxicity is Pyridoxine (vitamin B6) 5 g IV given over
10 minutes, or 1 g for each gram of INH ingested.
SPECIALCASES-DRUG-INDUCEDSEIZURES
20. - A febrile seizure is an event in
infancy or childhood usually
occurring between 6 months and 5
years of age, associated with fever,
but without evidence of intracranial
infection or de
fi
ned cause. Seizures
with fever in children who have
su
ff
ered a previous afebrile seizure
are excluded.
- Treatment is directed at identifying
the underlying cause of the fever
and at its symptomatic
management. It is important to
ensure adequate hydration by
encouraging the child to drink, and
paracetamol or ibuprofen can be
administered to relieve the
temperature.
SPECIALCASES-FEBRILE
SEIZURES
21. - Alcohol withdrawal seizures (AWS) are a leading cause of seizures in adults. These
seizures often occur as part of a constellation of early withdrawal symptoms typically
within 6 to 48 hours after the last drink.
- Other withdrawal symptoms including sweating, anxiety, tremor, auditory/visual
hallucinations, agitation, nausea/vomiting, headache, and disorientation often occur
prior to the onset of seizures.
- The more serious withdrawal syndrome of delirium tremens can be associated with
seizures that may occur as long as 7 days post alcohol cessation.
- Alcoholism is also a common cause of hypoglycemia and other metabolic abnormalities,
thus electrolytes should be checked.
- IV
fl
uid hydration with a glucose-containing solution in addition to thiamine, magnesium,
potassium, and multivitamins is also indicated.
- Use of benzodiazepines reduces the incidence of seizures and delirium.
SPECIALCASES-ALCOHOLWITHDRAWALSEIZURES
22. - Patients with psychogenic seizures tend to have multiple seizure patterns, which are
usually not followed by a postictal period. Urinary incontinence and injury such as tongue
biting has been reported in up to 20% of patients with psychogenic seizure.
- Unlike in physiologic seizures, noxious stimuli such as ammonia capsules may elicit
responses from patients having psychogenic seizures. The observation of purposeful
movement during a psychogenic seizure also is typical.
- Management of pseudoseizures involves reassurance and patient education with
psychiatric consultation often recommended.
SPECIALCASES-PSEUDOSEIZURES
23. - Eclampsia
- Magnesium sulfate 6 g IV over 15 minutes, then 2 g/h or 10 mg IM split in 2 separate
doses.
- Consider this etiology in women between 20 weeks’ gestation and 6 weeks’
postpartum.
- Hypoglycemia
- Dextrose 0.5–1 g/kg IV
- Hyponatremia
- 3% hypertonic saline 100–200 mL over 1 hour
SPECIALCASES
24. - In patients with known epilepsy who present with a single seizure, it is acceptable to send
laboratory test results for anticonvulsant levels, give a loading dose of the appropriate
anticonvulsant, and then discharge them with the appropriate follow-up.
- Patients without a history of epilepsy who present with a single unprovoked seizure, a more
thorough workup is indicated. If this initial workup is unremarkable, it is acceptable to
discharge the patient home with follow up neuroimaging and an appointment with a
neurologist.
- They will not necessarily need to be discharged on new antiepileptic medications but they
will need education about restrictions in patients with seizures.
- Patients without a history of seizure who do not return to baseline and remain postictal should
be admitted to the hospital until they return to their baseline mental status and the underlying
etiology of their seizures is determined
- Other indications include status epilepticus, the presence of a neurologic or systemic
illness or insult requiring additional evaluation and treatment, or questions regarding
compliance.
PATIENTDISPOSITION
25. - Patient education — Newly diagnosed patients with seizure and epilepsy may su
ff
er a
number of losses, including loss of independence, employment, insurance, ability to drive,
and self-esteem. As the treatment plan is formulated, these psychosocial issues should be
explored with patients so that appropriate referrals for additional help and counseling can
be initiated.
- All patients need to be provided detailed seizure precautions to limit activities where
sudden loss of consciousness would be especially dangerous such as operating heavy
equipment, swimming alone, cooking with hot water or even bathing.
PATIENTDISPOSITION
27. REFERENCES
- Bobak Zonnoor, M. D. (2022, July 5). Seizure assessment in the emergency
department. Overview, Pathophysiology, Etiology. Retrieved September 30,
2022, from https://emedicine.medscape.com/article/1609294-overview#a1
- MCGRAW-HILL EDUCATION. (2022). Case files emergency medicine.
- Steven C Schachter, MD. (n.d.). UpToDate. Retrieved September 30, 2022, from
https://www.uptodate.com/contents/evaluation-and-management-of-the-first-
seizure-in-adults?
search=seizures+&source=search_result&selectedTitle=1~150&usage_type=defa
ult&display_rank=1#H1057053825
