What are the recent guidelines for managing preeclampsia?

Recent Guidelines on Preeclampsia Management

The definitive management of preeclampsia involves antihypertensive treatment for severe hypertension, magnesium sulfate for seizure prophylaxis in severe cases, and delivery timing based on disease severity and gestational age. 1

Diagnosis and Definition

• Preeclampsia is defined as gestational hypertension (after 20 weeks) accompanied by ≥1 of the following new-onset conditions:

  • Proteinuria (present in ~75% of cases but not required for diagnosis)
  • Thrombocytopenia (<100,000/μL)
  • Renal insufficiency
  • Impaired liver function
  • Pulmonary edema
  • Cerebral or visual symptoms 1

• Severe features of preeclampsia include:

  • Systolic BP ≥160 mmHg or diastolic BP ≥110 mmHg
  • Platelet count <100,000/μL
  • Liver transaminases >2× upper limit of normal
  • Serum creatinine >1.1 mg/dL or doubling of baseline
  • Pulmonary edema
  • New-onset cerebral or visual disturbances
  • Severe persistent right upper quadrant pain 1, 2

Risk Assessment and Screening

• All pregnant women should be screened for preeclampsia with blood pressure measurements at each prenatal visit 3

• High-risk factors include:

  • History of preeclampsia (particularly early-onset)
  • Previous adverse pregnancy outcome
  • Pre-existing conditions (type 1/2 diabetes, chronic hypertension, renal disease, autoimmune diseases)
  • Multifetal gestation
  • Nulliparity, obesity, African American race, low socioeconomic status, advanced maternal age 3

• Proper BP measurement technique:

  • Patient should be relaxed, seated for 5 minutes
  • Sitting position with legs uncrossed and back supported
  • Arm at heart level
  • Use large BP cuff if upper arm circumference ≥33 cm
  • Avoid left lateral position (falsely lowers readings) 3

Prevention Strategies

• Low-dose aspirin (81 mg/day) should be initiated between 12-16 weeks of gestation and continued until delivery for high-risk women, reducing preeclampsia risk by 24% 1
• Calcium supplementation (1.2-2.5 g/day) is recommended for women with low calcium intake (<600 mg/day) 3, 1
• Regular exercise following ACOG guidelines (at least 3 days/week for 50 minutes using aerobic exercise, strength, and flexibility training) is recommended 3, 1
• Vitamin C and E supplements are NOT recommended and may worsen pregnancy outcomes 3, 1

Management of Preeclampsia

Preeclampsia without Severe Features

• Twice-weekly BP monitoring
• Antenatal testing for fetal well-being and disease progression
• Delivery by 37 weeks' gestation 2

Preeclampsia with Severe Features

• Immediate stabilization and inpatient treatment with:
  1. Magnesium sulfate for seizure prophylaxis
  2. Antihypertensive drugs for severe hypertension
  3. Corticosteroids for fetal lung maturity if <34 weeks' gestation
  4. Delivery planning 2

Antihypertensive Management

• Severe hypertension (SBP ≥160 mmHg and/or DBP ≥110 mmHg) requires immediate treatment
• First-line IV medications include:
  • Labetalol
  • Hydralazine
  • Oral nifedipine
• Target BP: diastolic 85 mmHg, systolic 110-140 mmHg 1

Magnesium Sulfate Administration

• For severe preeclampsia or eclampsia, the total initial dose is 10-14 g
• IV loading dose: 4-5 g in 250 mL of 5% Dextrose or 0.9% Sodium Chloride over 15-20 minutes
• Maintenance: 1-2 g/hour by continuous IV infusion
• Continue for at least 24 hours postpartum
• Target serum magnesium level: 6 mg/100 mL
• Maximum daily dose: 30-40 g/24 hours
• Reduce dose in renal insufficiency (maximum 20 g/48 hours) 4, 1

Delivery Timing

• Preeclampsia without severe features: delivery at 37 weeks' gestation
• Severe preeclampsia: delivery after 34 weeks' gestation
• Between 24-34 weeks with severe features: consider conservative management in selected patients with close monitoring
• Administer antenatal corticosteroids for fetal lung maturity if <34 weeks
• Consider termination of pregnancy if severe preeclampsia occurs before 24 weeks
• Immediate delivery is indicated for maternal end-organ dysfunction or non-reassuring fetal testing at any gestational age 1, 2

Fetal Monitoring

• Perform fetal biometry, amniotic fluid volume assessment, and fetal Doppler waveform analysis at first diagnosis
• Serial evaluation of fetal growth, amniotic fluid volume, and umbilical artery Doppler recommended from 24 weeks until birth
• Evaluate fetal growth no more frequently than every 2 weeks
• More frequent ultrasound measurements needed with high umbilical artery resistance or absent/reversed end-diastolic flow 3, 1

Postpartum Monitoring

• Continue blood pressure monitoring every 4-6 hours for at least 72 hours postpartum
• Taper antihypertensive medications slowly after days 3-6
• Follow-up within 1 week if still on antihypertensives at discharge 1
• Preeclampsia can worsen or initially present after delivery, requiring close monitoring 2

HELLP Syndrome Management

• HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets) occurs in 0.2%-0.6% of pregnancies
• Immediate delivery is the definitive treatment regardless of gestational age
• Platelet transfusion recommended if count <50,000/mm³, especially prior to Caesarean section
• Abdominal imaging should be performed to rule out hepatic complications 1

Long-term Considerations

• Preeclampsia is a risk factor for developing cardiovascular disease later in life
• Long-term follow-up is recommended for women with history of preeclampsia 5