What is the treatment for a 7-month pregnant woman experiencing convulsions?

Management of Convulsions in a 7-Month Pregnant Woman

Immediate administration of intravenous magnesium sulfate is the first-line treatment for convulsions in a 7-month pregnant woman, as it is superior to other anticonvulsants for preventing and treating eclamptic seizures. 1

Initial Assessment and Stabilization

• Convulsions in a 7-month pregnant woman should be treated as eclampsia until proven otherwise, requiring immediate intervention 2
• Urgent blood pressure measurement is essential, as severe hypertension (>160/110 mmHg) often accompanies eclampsia and requires immediate treatment 2
• Position the patient in left lateral decubitus position to improve venous return and prevent aortocaval compression 2
• Ensure airway patency and administer oxygen if needed 2

First-Line Treatment: Magnesium Sulfate

• Administer magnesium sulfate as the drug of choice for prevention and treatment of eclamptic seizures 2
• Use one of these regimens:
  • Intravenous protocol: 4g IV loading dose followed by maintenance infusion of 1-2g/hour 2, 3
  • Combined protocol (MAGPIE trial): 4g IV loading dose with 5g IM in each buttock (14g total loading), followed by 5g IM every 4 hours as maintenance 2
• Monitor for magnesium toxicity by checking:
  • Respiratory rate (should remain >16 breaths/min)
  • Patellar reflexes (should be present)
  • Urine output (should be >100 mL in 4 hours)
  • Serum magnesium levels if available (therapeutic range: 2.5-7.5 mEq/L) 3
• Have calcium gluconate immediately available as an antidote for magnesium toxicity 3

Management of Severe Hypertension

• Treat severe hypertension (BP ≥160/110 mmHg) immediately to prevent stroke and other complications 2
• First-line antihypertensive options include:
  • Intravenous labetalol: 10-20 mg IV initially, then 20-80 mg every 30 minutes to maximum 300 mg 2
  • Oral nifedipine: 10-20 mg, repeat in 30 minutes if needed 2
  • Intravenous hydralazine: 5 mg IV initially, then 5-10 mg every 30 minutes to maximum 30 mg 2
• Target blood pressure should be 140-150/85-100 mmHg; avoid rapid or excessive lowering which can compromise uteroplacental perfusion 2, 4

Ongoing Management

• Continue magnesium sulfate for at least 24 hours after the last seizure or delivery, whichever comes last 2
• Monitor maternal vital signs, urine output, and neurological status frequently 2
• Perform laboratory tests including complete blood count, liver enzymes, renal function, coagulation profile, and urine protein 2
• Assess fetal well-being with continuous electronic fetal monitoring 2

Delivery Considerations

• After maternal stabilization, delivery planning should be initiated, as delivery is the definitive treatment for eclampsia 2
• At 7 months (approximately 28-32 weeks), administer corticosteroids for fetal lung maturation if not previously given 2
• Mode of delivery should be based on obstetric indications; vaginal delivery is preferred when feasible 2
• Timing of delivery depends on:
  • Maternal condition stability
  • Fetal status
  • Gestational age
  • Response to initial treatment 2

Important Cautions

• Avoid sodium nitroprusside except as a last resort for the shortest possible time due to risk of fetal cyanide poisoning 2
• Do not administer calcium channel blockers (like nifedipine) simultaneously with magnesium sulfate due to risk of severe hypotension 2
• Phenytoin is inferior to magnesium sulfate for prevention of eclamptic seizures and should not be used as first-line therapy 1, 5
• Continuous administration of magnesium sulfate beyond 5-7 days can cause fetal bone abnormalities 3

Post-Seizure Care

• After seizure control, maintain close monitoring for recurrent seizures, as eclampsia can recur 2
• Continue antihypertensive therapy as needed to maintain blood pressure <150/100 mmHg 2
• Monitor for complications such as pulmonary edema, renal failure, and HELLP syndrome 2, 4