What is the management of a seizure in a pregnant patient?

Management of Seizures in Pregnant Patients

Activate emergency medical services immediately for any seizure in a pregnant patient, as this represents a critical medical emergency requiring urgent evaluation and intervention. 1, 2

Immediate First Aid Management

Position the patient on their side in the recovery position to minimize aspiration risk, help them safely to the ground if still seizing, and clear the surrounding area of hazards. 1

• Stay with the patient throughout the seizure and postictal period 1
• Do not restrain the patient or place anything in their mouth 1
• Do not give oral medications, food, or liquids during the seizure or if consciousness is impaired 1
• Monitor seizure duration carefully, as seizures lasting >5 minutes require immediate emergency intervention with anticonvulsant medications 1

Emergency Department Evaluation

For new-onset seizures in pregnancy, perform the same comprehensive workup as non-pregnant patients, including head CT with appropriate abdominal shielding. 3

Essential Initial Testing

• Serum glucose and sodium levels 4
• Pregnancy test confirmation (if status unknown) 4
• Consider lumbar puncture if meningitis or encephalitis suspected 1
• Toxicology screening if drug exposure suspected 1, 4
• Complete neurological examination with attention to focal deficits 4

Risk Stratification

• Document whether this is a first-time seizure or recurrent epilepsy 1, 2
• Assess for return to neurological baseline within 5-10 minutes after seizure cessation 1
• Evaluate for seizure-related injuries, respiratory compromise, or trauma 1

Status Epilepticus Management

For seizures lasting >5 minutes or multiple seizures without return to baseline, treat aggressively with IV benzodiazepines followed by phenytoin or phenobarbital, as rapid seizure control is essential for good fetal outcome. 3

• The risk to the fetus from uncontrolled seizures substantially exceeds the risk from anticonvulsant exposure 3, 5
• Fetal deaths after generalized seizures, though rare, have been documented, with marked declines in fetal heart rate observed during maternal seizures 5

Eclampsia Considerations

If eclampsia is suspected (seizure with hypertension/proteinuria), magnesium sulfate remains the standard initial treatment despite limited evidence of direct anticonvulsant properties. 6, 3

• Initial IV dose: 4-5 g magnesium sulfate in 250 mL fluid infused over 3-4 minutes, followed by 1-2 g/hour continuous infusion 6
• Alternative: 4 g IV plus 10 g IM (5 g in each buttock), then 4-5 g IM every 4 hours as needed 6
• Target serum magnesium level: 6 mg/100 mL (optimal for seizure control) 6
• Monitor patellar reflexes before each dose; absent reflexes indicate magnesium toxicity 6
• Monitor respiratory rate (should be ≥16 breaths/minute) 6
• Do not continue magnesium sulfate beyond 5-7 days, as prolonged use causes fetal abnormalities including hypocalcemia, skeletal demineralization, and osteopenia 6

Antiepileptic Drug Management in Known Epilepsy

For women with known epilepsy on treatment, maintain current antiepileptic medications during acute seizure management, as the risks of uncontrolled seizures outweigh medication risks. 2, 3, 7

Key Principles

• Approximately one-third of women with epilepsy experience increased seizure frequency during pregnancy 8, 2
• Antiepileptic drug levels decline progressively during pregnancy even with constant dosing, requiring frequent monitoring and dose adjustments 2, 5
• Never abruptly discontinue antiepileptic medications during pregnancy, as breakthrough seizures pose catastrophic risks 2

Medication Safety Considerations

• Valproate must be avoided or discontinued due to high teratogenic risk, particularly at doses >800 mg/day 2, 7
• Lamotrigine and levetiracetam have favorable safety profiles and should be encouraged for breastfeeding 8, 2
• Oxcarbazepine presents a favorable teratogenic profile with serum level monitoring recommended 8
• Aim for monotherapy at the lowest effective dose, as polytherapy increases teratogenic risk 8, 2

Disposition and Follow-up

Admit all pregnant patients with seizures for observation, coordinated obstetrical and neurological care, and fetal monitoring. 2, 3

• Early seizure recurrence is highest within the first 6 hours (mean 121 minutes), with >85% occurring within 360 minutes 1
• Arrange consultation with maternal-fetal medicine and neurology 2
• Ensure high-dose folic acid supplementation (4 mg daily) is initiated or continued 8, 2
• Schedule frequent prenatal visits for ongoing seizure and pregnancy monitoring 2

Common Pitfalls to Avoid

• Failing to activate EMS for any seizure in pregnancy 1, 2
• Delaying treatment of status epilepticus due to concerns about medication effects 3
• Discontinuing antiepileptic medications abruptly due to pregnancy concerns 2
• Continuing magnesium sulfate beyond 5-7 days in eclampsia management 6
• Inadequate monitoring of antiepileptic drug levels during pregnancy 2, 5