What is the current protocol for managing pre-eclampsia?

Current Pre-eclampsia Management Protocol

All women with newly diagnosed pre-eclampsia should be hospitalized initially for assessment, followed by urgent blood pressure control if severe (>160/110 mmHg), magnesium sulfate for seizure prophylaxis in severe cases, and delivery planning based on gestational age and severity. 1, 2

Diagnosis and Initial Assessment

• Pre-eclampsia is diagnosed by new-onset hypertension (≥140/90 mmHg) after 20 weeks of gestation with either proteinuria or evidence of end-organ damage 1
• Hospitalize all women initially to confirm diagnosis, assess severity, and establish baseline maternal and fetal status 1, 3
• Blood pressure should be measured every 4 hours (more frequently if severe hypertension present) 1
• Obtain baseline laboratory tests at least twice weekly: complete blood count focusing on hemoglobin and platelet count, liver transaminases, creatinine, and uric acid 4, 1
• Perform clinical assessment including evaluation for clonus and neurological symptoms 1
• Initial fetal assessment with ultrasound to evaluate fetal biometry, amniotic fluid volume, and umbilical artery Doppler 1, 2

Blood Pressure Management

Severe Hypertension (>160/110 mmHg)

Requires urgent treatment in a monitored setting: 4, 1

• First-line: Oral nifedipine 10 mg, repeat every 20 minutes to maximum 30 mg 1, 3
• Alternative: IV labetalol 20 mg bolus, then 40 mg after 10 minutes if needed, followed by 80 mg every 10 minutes to maximum 220 mg 1
• Alternative: IV hydralazine 4, 2

Non-Severe Hypertension (≥140/90 mmHg)

• Initiate oral antihypertensive therapy targeting diastolic BP of 85 mmHg and systolic BP between 110-140 mmHg 4, 1
• Acceptable first-line agents: oral methyldopa, labetalol, oxprenolol, or nifedipine 4
• Second or third-line agents: hydralazine or prazosin 4
• Reduce or cease antihypertensives if diastolic BP falls below 80 mmHg 4

Seizure Prophylaxis with Magnesium Sulfate

Administer magnesium sulfate for convulsion prophylaxis in women with: 4, 1

• Pre-eclampsia with severe hypertension (≥160/110 mmHg), OR
• Any hypertension with neurological signs or symptoms 4, 1

Dosing Protocol 5

• Loading dose: 4-5 g IV in 250 mL of 5% dextrose or 0.9% saline infused over 3-4 minutes 5
• Maintenance: 1-2 g/hour by continuous IV infusion 1
• Alternative regimen: 4 g IV loading dose, then 4-5 g IM into alternate buttocks every 4 hours 5
• Continue for 24 hours postpartum 1
• Target serum magnesium level: 6 mg/100 mL (optimal for seizure control) 5
• Maximum total daily dose: 30-40 g (20 g/48 hours in severe renal insufficiency) 5

Critical Monitoring During Magnesium Sulfate

• Check patellar reflexes and respiratory function before each dose 5
• Deep tendon reflexes disappear at plasma levels approaching 10 mEq/L 5
• Respiratory paralysis may occur at 10 mEq/L 5
• Do not exceed 5-7 days of continuous administration due to risk of fetal bone abnormalities 5

Fluid Management

• Strictly limit total fluid intake to 60-80 mL/hour to prevent pulmonary edema 1, 3
• Aim for euvolemia; avoid "running dry" as this increases acute kidney injury risk 1

Fetal Monitoring

• Initial assessment to confirm fetal well-being 4, 1
• Serial ultrasound surveillance including fetal biometry, amniotic fluid assessment, and umbilical artery Doppler 1
• In presence of fetal growth restriction, follow recommended schedule for serial fetal surveillance 4

Timing of Delivery

Delivery is the definitive treatment for pre-eclampsia 1

Immediate Delivery Indications (Regardless of Gestational Age) 1, 2, 3

• Repeated episodes of severe hypertension despite treatment with 3 classes of antihypertensives
• Progressive thrombocytopenia
• Progressively abnormal liver or renal function tests
• Neurological complications (severe intractable headache, repeated visual scotomata, eclamptic seizures)
• Pulmonary edema
• Placental abruption
• Non-reassuring fetal status
• Oxygen saturation <90%

Gestational Age-Based Delivery Timing

• ≥37 weeks: Deliver immediately 1, 2
• 34-37 weeks: Expectant management with close monitoring acceptable in absence of severe features 2
• <34 weeks: Expectant management at perinatal center with aggressive monitoring 3
• <24 weeks: Transfer to tertiary perinatal center; discuss termination 3

Postpartum Management

• Continue close monitoring for at least 3 days postpartum as eclampsia can still develop 1, 3
• Monitor BP at least every 4 hours while awake 1
• Continue antihypertensives and taper slowly only after days 3-6 postpartum 1, 3

Prevention for High-Risk Women

• Low-dose aspirin (75-162 mg/day, typically 81 mg) starting before 16 weeks' gestation (definitely before 20 weeks) for women with strong clinical risk factors 4, 1
• Supplemental calcium (1.2-2.5 g/day) if dietary intake is likely low (<600 mg/day) 1

Important Caveats

• All cases of pre-eclampsia should be considered potentially severe as they can rapidly progress to emergencies 2
• Blood pressure alone is not a reliable indicator of disease severity; serious organ dysfunction can develop at relatively mild levels of hypertension 2
• Neither serum uric acid nor the level of proteinuria should be used as an indication for delivery 2
• Plasma volume expansion is not recommended routinely 2
• Counsel all women about increased lifetime cardiovascular risk including stroke, diabetes, venous thromboembolism, and chronic kidney disease 1, 3