What is the management for a patient with preeclampsia at 22 weeks of gestation?

Management of Preeclampsia at 22 Weeks Gestation

At 22 weeks gestation with preeclampsia, expectant management with intensive maternal and fetal monitoring is the primary approach, as immediate delivery at this gestational age results in extremely poor neonatal outcomes, but you must be prepared for urgent delivery if maternal or fetal deterioration occurs. 1, 2

Initial Assessment and Severity Classification

• Confirm the diagnosis by documenting blood pressure ≥140/90 mmHg on repeat measurements and assess for proteinuria using urine protein/creatinine ratio (≥30 mg/mmol is abnormal). 1

• Immediately evaluate for severe features including:

  • Severe hypertension (≥160/110 mmHg) 1, 3
  • Thrombocytopenia (<100,000/μL) 3
  • Liver transaminases >2x normal 3
  • Renal dysfunction (elevated creatinine) 1, 3
  • Pulmonary edema 1
  • Severe persistent headache, visual disturbances, or epigastric/right upper quadrant pain 1, 3

• Obtain baseline laboratory tests at least twice weekly: complete blood count with hemoglobin and platelets, liver enzymes, creatinine, and uric acid. 1

Blood Pressure Management

• For severe hypertension (≥160/110 mmHg), initiate urgent antihypertensive therapy within 15 minutes to prevent maternal stroke, targeting systolic BP 110-140 mmHg and diastolic BP 85 mmHg. 1, 4

• First-line medications include:

  • Oral nifedipine 4
  • IV labetalol (100 mg twice daily up to 2400 mg/day) 1, 4
  • IV hydralazine 1, 4

• Avoid ACE inhibitors, ARBs, and direct renin inhibitors—these are absolutely contraindicated due to severe fetotoxicity causing renal dysgenesis. 1, 4

• Avoid diuretics as they further reduce plasma volume, which is already compromised in preeclampsia and can worsen uteroplacental perfusion. 1

Magnesium Sulfate for Seizure Prophylaxis

• Administer magnesium sulfate if severe features are present (severe hypertension with proteinuria or any hypertension with neurological symptoms) to prevent eclamptic seizures. 4, 5

• Dosing: 4-5g IV loading dose over 5 minutes, followed by 1-2g/hour continuous IV infusion. 4, 6

• Monitor for magnesium toxicity by checking:

  • Patellar reflexes (knee jerk) before each dose—if absent, hold magnesium 6
  • Respiratory rate (maintain ≥16 breaths/minute) 6
  • Urine output (maintain ≥100 mL/4 hours) 6
  • Therapeutic serum magnesium levels are 3-6 mg/100 mL (2.5-5 mEq/L) 6

• Keep IV calcium gluconate immediately available to reverse magnesium toxicity if respiratory depression or loss of reflexes occurs. 6

Maternal Monitoring Protocol

• Monitor blood pressure continuously or every 4 hours while awake. 1

• Perform clinical assessments including deep tendon reflexes and clonus evaluation. 1

• Repeat laboratory tests (hemoglobin, platelets, liver enzymes, creatinine, uric acid) at least twice weekly or more frequently if clinical deterioration occurs. 1

• Assess daily for symptoms of disease progression: severe headache, visual disturbances, epigastric or right upper quadrant pain, and shortness of breath. 1, 3

Fetal Surveillance

• Initiate serial ultrasound assessments for fetal biometry, amniotic fluid volume, and umbilical artery Doppler to monitor for intrauterine growth restriction. 1

• Perform electronic fetal heart rate monitoring to assess fetal well-being. 1

• Repeat fetal surveillance at intervals determined by severity of maternal condition and presence of fetal growth restriction. 1

Expectant Management Strategy at 22 Weeks

• At 22 weeks gestation, expectant management is appropriate only if maternal condition is stable and fetal status is reassuring, as delivery at this gestational age is associated with extremely high neonatal mortality and morbidity. 2

• This approach aims to prolong pregnancy to improve neonatal outcomes, with most studies showing 7-10 days of prolongation with expectant management. 2

• Expectant management at 24 0/7 weeks or earlier is associated with high maternal morbidity and limited perinatal benefit, making the risk-benefit calculation particularly challenging. 2

Corticosteroids for Fetal Lung Maturity

• Administer antenatal corticosteroids immediately to accelerate fetal lung maturation, as delivery may become necessary at any time. 1, 3

• This is critical for pregnancies <34 weeks gestation to reduce neonatal respiratory distress syndrome and mortality. 3

Indications for Immediate Delivery (Regardless of Gestational Age)

• Deliver immediately if any of the following develop:
  • Repeated episodes of severe hypertension despite treatment with 3 antihypertensive drug classes 1
  • Progressive thrombocytopenia 1
  • Progressively abnormal liver or renal function tests 1
  • Pulmonary edema 1
  • Severe intractable headache, repeated visual scotomata, or eclamptic seizures 1
  • Non-reassuring fetal status 1
  • Placental abruption 3
  • HELLP syndrome with maternal end-organ dysfunction 3

Critical Pitfalls to Avoid

• Do not use blood pressure level alone to determine disease severity—serious organ dysfunction can develop at relatively mild blood pressure elevations. 7

• Do not use serum uric acid level or degree of proteinuria as indications for delivery; these do not reliably predict outcomes. 7

• Do not administer NSAIDs for analgesia if delivery occurs, as they can worsen renal function in preeclampsia. 1

• Do not use low molecular weight heparin for prevention, as it is not indicated even with prior early-onset preeclampsia. 1

• Recognize that preeclampsia at 22 weeks can progress rapidly and unpredictably—maintain a low threshold for delivery if maternal or fetal deterioration occurs, as maternal safety is the absolute priority. 2, 8

Hospital Setting Requirements

• Management must occur in a hospital with appropriate obstetrical care facilities, maternal intensive care capabilities, and neonatal intensive care unit for extremely premature infants. 6

• Coordinate care with maternal-fetal medicine specialists, neonatology, and anesthesiology teams given the high-risk nature of preeclampsia at this early gestational age. 4