What is the immediate treatment for a patient with eclampsia?

Immediate Treatment for Eclampsia

Administer intravenous magnesium sulfate immediately as first-line anticonvulsant therapy, with a loading dose of 4-5g IV over 5 minutes followed by 1-2g/hour continuous infusion, while simultaneously controlling blood pressure below 160/105 mmHg using IV labetalol or nicardipine. 1, 2, 3

Seizure Control with Magnesium Sulfate

Magnesium sulfate is the definitive anticonvulsant for eclampsia and must be started immediately upon diagnosis. 1, 2

Loading Dose Options:

• IV route (preferred): 4-5g magnesium sulfate diluted in 250mL of 5% dextrose or 0.9% saline, infused over 5 minutes 1, 2, 3
• Combined IV/IM route: 4g IV over 5 minutes PLUS 10g IM (5g in each buttock) for total loading dose of 14g 2, 3
• IM only (if IV access unavailable): 10g IM total (5g in each buttock), then refer immediately 2

Maintenance Dosing:

• Continuous IV infusion: 1-2g/hour for 24 hours after the last seizure 1, 2, 3
• Intermittent IM: 5g IM every 4 hours in alternating buttocks (if IV infusion pump unavailable) 2, 3

Critical Monitoring During Magnesium Administration:

• Patellar reflexes before each dose - absence indicates magnesium toxicity and requires withholding further doses 3
• Respiratory rate >16 breaths/minute - respiratory depression occurs at serum levels 5-6.5 mmol/L 3, 4
• Urine output >100mL over 4 hours preceding each dose 2, 3
• Serum magnesium levels: therapeutic range 1.8-3.0 mmol/L (4-6 mg/dL); toxicity begins >3.5 mmol/L 4

Magnesium Toxicity Management:

• Have injectable calcium gluconate or calcium chloride immediately available at bedside to counteract toxicity 1, 3
• Loss of patellar reflexes occurs at 3.5-5 mmol/L 3, 4
• Respiratory paralysis at 5-6.5 mmol/L 3, 4
• Cardiac arrest risk >12.5 mmol/L 4

Blood Pressure Management

Target blood pressure <160/105 mmHg to prevent maternal cerebrovascular complications, which are the leading cause of maternal death in eclampsia. 1, 2, 5

First-Line IV Antihypertensives:

Labetalol (preferred):

• Initial bolus: 20mg IV 1, 2
• If inadequate response after 10 minutes: 40mg IV 1, 2
• Then 80mg IV every 10 minutes to maximum cumulative dose of 220mg 1, 2

Nicardipine (alternative):

• Start at 5mg/hour IV infusion 1, 2
• Increase by 2.5mg/hour every 5-15 minutes 1, 2
• Maximum 15mg/hour 1, 2

Critical Precautions:

• Avoid combining magnesium sulfate with calcium channel blockers (nifedipine, nicardipine) due to severe hypotension risk 1, 2
• Never use sodium nitroprusside - causes fetal cyanide toxicity 2
• Avoid diuretics - plasma volume is already reduced in eclampsia 1, 2
• If blood pressure control not achieved within 360 minutes despite two medications, transfer to ICU 1

Alternative Antihypertensives:

• Oral nifedipine or oral methyldopa when IV agents unavailable 2
• IV hydralazine as second-line option, but administer cautiously to avoid precipitous blood pressure drops that reduce uteroplacental perfusion 1, 6

Airway and Acute Seizure Management

During active seizure, prioritize airway protection, positioning patient in left lateral decubitus position, and ensuring safety during convulsions. 7

• Maintain airway patency and adequate oxygenation 7
• Position patient to prevent aspiration 7
• Protect from physical injury during convulsions 7
• Administer supplemental oxygen as needed 7

Delivery Planning

Delivery is the definitive treatment for eclampsia and should occur after maternal stabilization. 1, 2, 7

Immediate Delivery Indications:

• Inability to control blood pressure despite two antihypertensives 2
• Progressive deterioration in liver function, creatinine, hemolysis, or platelet count 2
• Ongoing neurological features despite treatment 2
• Placental abruption 2
• Abnormal fetal status 2
• Gestational age ≥37 weeks 2

Delivery Mode:

• Vaginal delivery preferred unless cesarean indicated for obstetric reasons 2
• Neuraxial anesthesia is preferred for cesarean section in seizure-free, stable patients 7

Corticosteroids:

• Administer antenatal corticosteroids if gestational age ≤34 weeks to accelerate fetal lung maturation 2
• May be given up to 38 weeks for elective cesarean 2
• Multiple courses not recommended 2

Continuous Monitoring Requirements

Implement intensive maternal and fetal monitoring throughout treatment. 2

Maternal Monitoring:

• Continuous blood pressure monitoring 2
• Deep tendon reflexes before each magnesium dose 2, 3
• Respiratory rate continuously 2, 3
• Urine output hourly 2, 3
• Laboratory tests: hemoglobin, platelet count, liver enzymes, creatinine, uric acid 2

Fetal Monitoring:

• Continuous fetal heart rate monitoring 2
• Ultrasound assessment of fetal biometry, amniotic fluid, and umbilical artery Doppler 2

Postpartum Management

Continue magnesium sulfate for 24 hours after delivery or last seizure, whichever is later. 2

• Continue antihypertensive therapy during labor and postpartum period 2
• Monitor blood pressure hourly for first 12 hours postpartum 6
• Check blood pressure and urine at 6 weeks postpartum 2
• Assess for secondary causes of hypertension in women <40 years with persistent hypertension 2

Common Pitfalls to Avoid

• Never administer magnesium sulfate for >5-7 days - causes fetal hypocalcemia, skeletal demineralization, osteopenia, and neonatal fractures 3
• Do not lower blood pressure too rapidly - can cause fetal bradycardia from reduced uteroplacental perfusion 6
• Avoid fluid overload - eclamptic patients have hemoconcentration and are at high risk for pulmonary edema 6
• Do not use phenytoin - magnesium sulfate is superior for eclampsia prevention (0% vs 0.9% seizure rate) 8
• Magnesium sulfate 50% solution must be diluted to ≤20% concentration before IV infusion 3
• Maximum IV injection rate should not exceed 150mg/minute except during active seizures 3