Seizure at 37 Weeks Gestation
A 29-year-old woman at 37 weeks gestation is found seizing on her living room floor. Her husband says the generalized seizure lasted about 90 seconds and she has had a severe headache and blurred vision since this morning. She has no prenatal care and no history of epilepsy. Vital signs after the seizure: BP 176/110, HR 118, RR 26, SpO2 93% on room air, temperature 37.0°C. She is postictal, moaning, and does not follow commands. Her face and hands are edematous. Fingerstick glucose is 112 mg/dL. Fetal heart tones are 150 by Doppler. The nearest hospital is 15 minutes away and has no obstetrics; the OB center with high-risk services is 35 minutes away.
1. What is the most likely cause of the seizure, and what is your first-line medication? Defend the choice.
Read the worked answer
This is eclampsia until proven otherwise: seizure in late pregnancy with BP 176/110, headache, visual changes, and edema. Hypoglycemia is excluded by glucose 112. First-line is magnesium sulfate, 4-6 g IV over 15-20 minutes, then 1-2 g/hr, because it prevents recurrent seizures and treats the underlying eclamptic process better than a benzodiazepine alone. Check deep tendon reflexes, respiratory rate, and urine output before and during infusion; loss of reflexes, respiratory depression, or oliguria signals toxicity and you would stop and consider calcium gluconate. Give oxygen, position left lateral, and protect her from injury. Do not give nitroglycerin as first-line for the BP.
2. She seizes again en route. What is your sequence, and what do you avoid?
Read the worked answer
Protect the airway, suction if needed, give oxygen, and position her left lateral to reduce vena cava compression. Give an additional magnesium bolus (e.g., 2 g over 5 minutes) per protocol for recurrent seizure; if seizures continue, a benzodiazepine may be used cautiously, but magnesium is the eclampsia-specific treatment. Check glucose again. Do not attempt delivery on scene unless delivery is imminent; prepare for delivery en route if needed. Monitor fetal heart tones if possible, but maternal stabilization comes first. Avoid supine positioning and avoid unnecessary stimulation.
3. Destination decision: the 15-minute hospital without obstetrics or the 35-minute OB center? Explain.
Read the worked answer
Transport to the OB center with high-risk services, 35 minutes away, if she is stable enough. She needs magnesium infusion, blood pressure control, fetal monitoring, and possible delivery; the 15-minute hospital has no obstetrics and would likely transfer her, adding delay. Notify the OB center early and monitor for recurrent seizure, respiratory depression, and hypotension. If she has a second seizure, airway compromise, or imminent delivery, divert to the closest facility for stabilization and delivery. The decision hinges on maternal stability, not solely on distance.