Seizures
Seizures, also known as epileptic seizures or convulsions, are sudden, uncontrolled electrical disturbances in the brain that can cause changes in behavior, sensation, and awareness. They result from abnormal electrical activity in the brain's neurons. Seizures can vary widely in their presentation and severity, and they may be a symptom of an underlying neurological condition.
Type of Seizure
There are different types of seizures, and they are broadly classified into two main categories:
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Focal (Partial) Seizures:
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Simple Partial Seizures: These seizures do not cause loss of consciousness. The person may experience altered emotions, sensations, or movements.
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Complex Partial Seizures: These seizures can lead to a loss of consciousness or awareness. The person may exhibit unusual behaviors, movements, or automatisms (repetitive, purposeless actions).
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Generalized Seizures:
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Absence Seizures: Formerly known as petit mal seizures, these often occur in children and cause a brief loss of awareness or consciousness. The person may stare blankly for a few seconds.
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Tonic-Clonic Seizures: Formerly known as grand mal seizures, these are characterized by a sudden loss of consciousness, muscle stiffness (tonic phase), and rhythmic jerking movements (clonic phase). These seizures are often associated with a postictal state, where the person may be confused or fatigued after the seizure.
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Atonic Seizures: These seizures involve a sudden loss of muscle tone, leading to a person dropping or collapsing.
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Myoclonic Seizures: These seizures cause rapid, brief muscle jerks.
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Causes of Seizures
Seizures can be caused by various factors, including:
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Epilepsy: A chronic neurological disorder characterized by recurrent seizures.
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Brain Injury: Traumatic brain injuries, strokes, and other structural brain abnormalities can lead to seizures.
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Infections: Infections such as meningitis or encephalitis can trigger seizures.
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Metabolic Disorders: Imbalances in electrolytes, blood sugar, or other metabolic factors.
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Genetic Factors: Some individuals may have a genetic predisposition to seizures.
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Alcohol withdrawal seizures:
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Refer to seizures that can occur when individuals abruptly stop or significantly reduce their alcohol consumption.
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These seizures are part of a condition known as alcohol withdrawal syndrome, which can manifest with various symptoms, including tremors, anxiety, nausea, and, in severe cases, seizures.
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The abrupt cessation of alcohol can lead to hyperexcitability of the nervous system, triggering these seizures.
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The risk of alcohol withdrawal seizures is higher in individuals with a history of heavy and prolonged alcohol use. Seeking medical assistance is crucial for managing alcohol withdrawal and preventing complications such as seizures.
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Treatment for seizures often involves antiepileptic medications, lifestyle modifications, and in some cases, surgical interventions. It is crucial for individuals experiencing seizures to consult with a neurologist for a thorough evaluation and appropriate management.
Management of Status Epilepticus
Status epilepticus is defined as continuous or recurrent seizures lasting ≥5 minutes without recovery of consciousness between seizures.
The Canadian Neurological Sciences Federation and international guidelines provide a structured, stepwise approach to treatment:
General Principles
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Time is critical: Immediate action is required to prevent neuronal injury.
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ABC approach:
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Airway: Ensure the airway is clear and secure if compromised.
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Breathing: Administer oxygen and monitor respiratory function.
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Circulation: Establish IV access, check vital signs, and draw blood for investigations (e.g., glucose, electrolytes, AED levels, CBC, toxicology).
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Treatment Stages
Stage 1: Initial Therapy (0-5 minutes)
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Priority: Terminate seizures and correct any metabolic disturbances.
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Drug of Choice: Benzodiazepines (first-line).
Preferred Agents:
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IV Lorazepam: 0.1 mg/kg (max 4 mg/dose); may repeat after 10-15 minutes.
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IM Midazolam: 10 mg if no IV access (rapid onset and ease of use).
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IV Diazepam: 0.15-0.2 mg/kg (max 10 mg/dose); has a shorter duration of action.
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Check blood glucose: If hypoglycemic, administer 50 mL of Dextrose 50% (D50W).
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Thiamine: Give 100 mg IV/IM if alcohol misuse or malnutrition is suspected.
Stage 2: Established Status Epilepticus (5-20 minutes)
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If seizures persist despite benzodiazepines, administer a second-line antiseizure medication.
Second-line Options:
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IV Fosphenytoin: 20 mg PE/kg at a rate ≤150 mg PE/min.
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IV Phenytoin: 20 mg/kg at a rate ≤50 mg/min (cardiac monitoring required).
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IV Valproic Acid: 20-40 mg/kg (max 3,000 mg) infused over 10 minutes.
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IV Levetiracetam: 40-60 mg/kg (max 4,500 mg); may be preferred for fewer drug interactions.
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IV Phenobarbital: 15-20 mg/kg (used in refractory or specific cases).
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Monitor for side effects such as hypotension, bradycardia, or respiratory depression.
Stage 3: Refractory Status Epilepticus (20-40 minutes)
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If seizures continue after initial benzodiazepines and second-line agents:
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Initiate continuous IV anesthetic therapy under ICU care with EEG monitoring.
Third-line Options:
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IV Midazolam infusion: Loading dose: 0.2 mg/kg, then infusion at 0.05-2 mg/kg/hr.
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IV Propofol infusion: Loading dose: 1-2 mg/kg, then infusion at 2-5 mg/kg/hr.
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IV Phenobarbital infusion: 10-20 mg/kg loading dose followed by maintenance.
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Intubation and ICU monitoring: Continuous EEG is required to assess seizure activity.
Stage 4: Super-Refractory Status Epilepticus (>24 hours)
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If seizures persist despite continuous anesthetic infusions:
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Immunotherapy: Consider steroids, IVIG, or plasmapheresis (e.g., autoimmune encephalitis).
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Ketogenic Diet: In selected cases, especially in pediatric populations.
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Other Agents: Topiramate, lacosamide, or perioperative surgical interventions in extreme cases.
Investigations and Management of Underlying Causes
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Conduct parallel investigations while treating SE:
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Electrolytes, glucose, calcium, magnesium, renal/hepatic function, and toxicology screen.
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Infections: Consider lumbar puncture if encephalitis/meningitis is suspected.
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Imaging: Brain CT/MRI to evaluate for structural lesions (e.g., stroke, tumor).
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AED Levels: For patients with known epilepsy.
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Special Considerations
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Pregnancy: Benzodiazepines and levetiracetam are preferred; consult obstetrics.
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Alcohol-Related Seizures: Thiamine and benzodiazepines are key.
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Pediatric SE: Dosing is weight-based; midazolam and fosphenytoin are preferred.
Summary of Treatment Algorithm
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0-5 min: Benzodiazepine (IV lorazepam, IM midazolam).
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5-20 min: Second-line AED (fosphenytoin, valproic acid, levetiracetam).
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20-40 min: Continuous IV anesthetic therapy (midazolam, propofol, phenobarbital).
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>24 hours: Super-refractory measures (immunotherapy, ketogenic diet, advanced interventions).
Key Monitoring
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EEG: Continuous EEG for refractory cases to assess ongoing non-convulsive SE.
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Vitals: Monitor for respiratory depression, hypotension, and cardiac arrhythmias.
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Lab Work: Ongoing assessment for metabolic derangements and AED toxicity.
Prompt treatment with appropriate medications and escalation is critical to prevent neuronal injury, morbidity, and mortality.
Choric Seizure Management
The guidelines for chronic seizure treatment are based on recommendations from organizations like the Canadian Epilepsy Guidelines, the International League Against Epilepsy (ILAE), and the American Academy of Neurology (AAN).
1. Diagnosis and Classification
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Accurate Diagnosis: Determine seizure type (focal, generalized, or unknown) and epilepsy syndrome.
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Use EEG, MRI, and clinical history to guide diagnosis.
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Diagnosis must differentiate epilepsy from non-epileptic events (e.g., syncope, psychogenic seizures).
2. Pharmacological Therapy
First-Line Treatment
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Initiate antiseizure medication (ASM) based on seizure type and patient factors (age, comorbidities, pregnancy, etc.).
Medication Selection by Seizure Type
Seizure Type First-Line Medications
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Focal (Partial): SeizuresLevetiracetam, carbamazepine, lamotrigine, oxcarbazepine, lacosamide
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Generalized Tonic-Clonic: Valproic acid, lamotrigine, levetiracetam, topiramate
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Absence Seizures: Ethosuximide, valproic acid, lamotrigine
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Myoclonic Seizures: Valproic acid, levetiracetam, topiramate
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Monotherapy: Start with one ASM at a low dose and titrate up to therapeutic levels.
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Polytherapy: Add a second drug if seizures remain uncontrolled after two appropriate monotherapies. Choose drugs with complementary mechanisms and minimal interactions.
3. Considerations for Medication Choice
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Age: Tailor medications for elderly or pediatric populations (e.g., levetiracetam is preferred in older adults due to fewer side effects).
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Comorbidities: Address psychiatric disorders, liver/kidney dysfunction, and cognitive decline.
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Women of Childbearing Age:
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Avoid valproic acid due to teratogenicity.
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Lamotrigine or levetiracetam is preferred.
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Use folic acid supplementation (≥1 mg/day).
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Cost/Availability: Consider generic medications if appropriate.
4. Non-Pharmacological Management
Lifestyle Modifications
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Sleep: Ensure sufficient, consistent sleep. Sleep deprivation can trigger seizures.
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Avoid Triggers: Minimize alcohol, drugs, stress, and flashing lights (photosensitivity).
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Diet: For refractory epilepsy, consider the Ketogenic Diet or modified Atkins diet.
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Exercise: Regular physical activity can improve overall well-being.
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Driving Restrictions: Adhere to local driving regulations (e.g., seizure-free period required for driving).
5. Treatment for Drug-Resistant Epilepsy
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Definition: Failure of adequate trials of two appropriately chosen antiseizure medications.
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Evaluation: Refer to a comprehensive epilepsy center for advanced evaluation.
Surgical Options
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Resective Surgery: For focal epilepsy where the seizure focus can be identified (e.g., temporal lobe epilepsy).
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Laser Interstitial Thermal Therapy (LITT): Minimally invasive option for focal lesions.
Neuromodulation
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Vagus Nerve Stimulation (VNS): Implantable device to reduce seizure frequency in drug-resistant epilepsy.
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Responsive Neurostimulation (RNS): Targets seizure foci with electrical stimulation.
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Deep Brain Stimulation (DBS): For selected patients with generalized or focal seizures.
6. Monitoring and Follow-Up
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Regular follow-up to assess seizure frequency, medication side effects, and adherence.
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Therapeutic Drug Monitoring (TDM):
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Indicated for medications like valproic acid, phenytoin, carbamazepine, and phenobarbital.
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Bone Health: Long-term use of ASMs (e.g., valproic acid, phenytoin) can affect bone density. Screen for osteoporosis and supplement with calcium/vitamin D as needed.
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Cognitive and Mental Health: Monitor for depression, anxiety, and cognitive changes.
7. Special Populations
Women
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Preconception planning and pregnancy care: Optimize medication safety (e.g., avoid valproic acid).
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Monitor ASM levels during pregnancy, as metabolism may increase.
Elderly
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Start low and go slow; prioritize ASMs with fewer side effects (e.g., lamotrigine, levetiracetam).
Children
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Manage based on specific pediatric epilepsy syndromes.
Summary: Chronic Seizure Management
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Diagnosis: Identify seizure type and cause.
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First-Line Therapy: Start with appropriate monotherapy based on seizure type.
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Optimize Therapy: Address medication adherence and adverse effects.
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Drug-Resistant Cases: Refer for epilepsy surgery or neuromodulation.
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Lifestyle: Sleep hygiene, ketogenic diet, and avoidance of triggers.
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Monitoring: Follow up regularly, assess mental health, and monitor drug levels when needed.
By following these guidelines, the majority of patients with chronic seizures can achieve good seizure control, significantly improving their quality of life.