What is the management of eclampsia?

Management of Eclampsia

Immediately administer intravenous magnesium sulfate as the first-line anticonvulsant for seizure control, followed by antihypertensive therapy to maintain blood pressure below 160/105 mmHg, and proceed with delivery after maternal stabilization. 1, 2

Immediate Seizure Control with Magnesium Sulfate

Loading Dose

• Administer 4-5g IV magnesium sulfate over 5 minutes as the loading dose 1, 2
• Alternatively, give 4g IV combined with 10g IM (5g in each buttock) for a total loading dose of 14g 3, 2
• The IV route provides therapeutic levels almost immediately, while IM administration achieves therapeutic levels within 60 minutes 2

Maintenance Dose

• Continue with 1-2g/hour as continuous IV infusion for 24 hours after the last seizure 1, 2
• Alternatively, administer 5g IM every 4 hours in alternating buttocks 3, 2
• The 1g/hour maintenance dose is as effective as 2g/hour with fewer side effects 4
• Target therapeutic serum magnesium level of 3-6 mg/100 mL (2.5-5 mEq/L) for seizure control 5

Critical Monitoring During Magnesium Therapy

• Check patellar (knee jerk) reflexes before each dose—if absent, hold magnesium until reflexes return 2
• Monitor respiratory rate continuously; must be ≥16 breaths/minute 1, 2
• Maintain urine output >100 mL over 4 hours preceding each dose 1, 2
• Have injectable calcium salt immediately available to counteract magnesium toxicity 1, 2

Recognizing Magnesium Toxicity

• Loss of patellar reflexes occurs at 3.5-5 mmol/L (first warning sign) 5
• Respiratory depression/paralysis occurs at 5-6.5 mmol/L 5
• Cardiac conduction abnormalities occur at >7.5 mmol/L 5
• Cardiac arrest expected at >12.5 mmol/L 5

Blood Pressure Management

Target Blood Pressure

• Maintain BP <160/105 mmHg to prevent maternal complications including stroke 1
• Aim for systolic BP 140-150 mmHg and diastolic BP 90-100 mmHg 6

First-Line Antihypertensive Agents

• Labetalol IV: Give 20mg IV bolus, then 40mg after 10 minutes, followed by 80mg every 10 minutes to maximum cumulative dose of 220mg 1
• Nicardipine IV: Start at 5mg/h, increase by 2.5mg/h every 5-15 minutes to maximum 15mg/h 1
• Nifedipine oral: 10-20mg orally if IV access unavailable, but use extreme caution when combined with magnesium sulfate due to risk of profound hypotension 6

Antihypertensives to Avoid

• Sodium nitroprusside: Risk of fetal cyanide toxicity 1, 6
• Hydralazine: Associated with adverse perinatal outcomes 6
• Diuretics: Contraindicated as plasma volume is already reduced in preeclampsia 1

Delivery Planning

Timing of Delivery

• Deliver after maternal stabilization (seizures controlled, BP stabilized) 1
• Immediate delivery indications include: 1
  • Inability to control blood pressure despite multiple agents
  • Progressive deterioration in liver function, creatinine, or platelet count
  • Ongoing neurological features or recurrent seizures
  • Placental abruption
  • Abnormal fetal status
  • Gestational age ≥37 weeks

Mode of Delivery

• Vaginal delivery is preferred unless cesarean section is indicated for obstetric reasons 1
• Cesarean section should be performed primarily for obstetric indications, not eclampsia alone 7

Corticosteroids for Fetal Lung Maturation

• Administer antenatal corticosteroids if gestational age is ≤34 weeks 1
• May be given up to 38 weeks for elective cesarean section 3
• Multiple steroid courses are not recommended 3

Continuous Monitoring Requirements

Maternal Monitoring

• Continuous blood pressure monitoring throughout treatment 1
• Deep tendon reflexes before each magnesium dose 1, 2
• Respiratory rate (must be ≥16/minute) 1
• Urine output (>100 mL/4 hours) 1, 2
• Laboratory tests twice weekly: hemoglobin, platelet count, liver enzymes, creatinine, uric acid 1

Fetal Monitoring

• Continuous fetal heart rate monitoring 1
• Ultrasound assessment of fetal biometry, amniotic fluid volume, and umbilical artery Doppler 1

Post-Delivery Management

• Continue magnesium sulfate for 24 hours after delivery or last seizure 1
• Continue antihypertensive therapy during labor and postpartum period 1
• Check blood pressure and urine at 6 weeks postpartum 1
• Assess for secondary causes of hypertension in women under 40 with persistent hypertension 1

Critical Precautions and Drug Interactions

• Never exceed 5-7 days of continuous magnesium sulfate administration in pregnancy—causes fetal skeletal demineralization, osteopenia, and fractures 2
• Avoid combining magnesium sulfate with calcium channel blockers due to risk of severe hypotension 1
• Reduce dosage of barbiturates, narcotics, or anesthetics when given with magnesium due to additive CNS depression 2
• In severe renal insufficiency, maximum dose is 20g/48 hours with frequent serum magnesium monitoring 2
• Magnesium sulfate should be administered with extreme caution in digitalized patients due to risk of heart block 2

Special Considerations for Resource-Limited Settings

• If IV access unavailable, give IM loading dose of 5g magnesium sulfate in each buttock (10g total) and refer 3
• Methyldopa and nifedipine are acceptable oral antihypertensives when IV agents unavailable 3
• The Pritchard regimen (IM administration) can be used when IV infusion pumps are not available 3
• Task-shifting allows lower-level providers to initiate loading dose and refer 3