What is the best course of action for a 29.6 weeks gestation pregnant patient with a history of anemia (low red blood cell count) in a previous pregnancy, presenting with headache, blurred vision, and elevated blood pressure (hypertension), but with currently normal blood pressure readings, and a hemoglobin level of 9.4 indicating anemia?

Immediate Evaluation for Preeclampsia with Close Observation and Workup

This patient requires urgent evaluation for preeclampsia given her symptoms of headache and blurred vision at 29.6 weeks gestation, even though her blood pressure readings are currently at the threshold (130/75 mmHg). The combination of neurological symptoms with borderline elevated BP mandates immediate assessment for preeclampsia with severe features, as preeclampsia can progress unpredictably and represents a major threat to both mother and baby at any stage. 1

Classification and Risk Assessment

This patient presents with transient gestational hypertension - hypertension that arises after 20 weeks gestation but settles with repeated BP readings over several hours. 1 However, the critical concern is that:

• Transient gestational hypertension carries a 40% risk of developing true gestational hypertension or preeclampsia in the remainder of pregnancy, requiring careful follow-up. 1
• Her symptoms of headache and visual disturbance are severe features of preeclampsia due to cerebral edema, even when BP is not severely elevated. 1
• Preeclampsia is defined by hypertension (≥140/90 mmHg) with either proteinuria OR end-organ dysfunction including cerebral or visual symptoms - proteinuria is not required for diagnosis. 2

Immediate Diagnostic Workup Required

Perform the following tests immediately to assess for preeclampsia with severe features:

• Urine protein assessment: 24-hour urine collection for protein (≥0.3 g/24h indicates preeclampsia) or spot urine protein-to-creatinine ratio (≥30 mg/mmol). 1
• Complete blood count: Platelet count <100,000/µL indicates severe features. 2
• Liver function tests: Transaminases >2x upper limit of normal indicate severe features. 2
• Serum creatinine: Level >1.1 mg/dL or doubling from baseline indicates severe features. 2
• Continuous BP monitoring: Repeat BP measurements every 15 minutes initially, then hourly for several hours in a day assessment unit to confirm true hypertension versus transient elevation. 1, 3

Management Algorithm Based on Findings

If Preeclampsia WITHOUT Severe Features is Confirmed:

• Initiate antihypertensive therapy immediately at BP ≥140/90 mmHg given her gestational hypertension presentation. 1, 3, 4
• First-line medication: Oral methyldopa (gold standard with extensive long-term pediatric safety data) OR oral long-acting nifedipine OR oral labetalol. 3, 4
• Target BP: Systolic 110-140 mmHg and diastolic 85 mmHg to balance maternal protection with uteroplacental perfusion. 3, 4
• Twice-weekly BP monitoring initially, then weekly once stable, with proteinuria assessment at each visit. 4, 2
• Antenatal testing for fetal well-being and disease progression monitoring. 2
• Plan delivery at 37 weeks gestation if stable. 4

If Preeclampsia WITH Severe Features is Confirmed:

This becomes a hypertensive emergency requiring immediate hospitalization if any of the following are present: 1, 4, 2

• Persistent headache/visual disturbances (already present in this patient)
• BP ≥160/110 mmHg on repeat measurement
• Platelet count <100,000/µL
• Liver transaminases >2x normal
• Serum creatinine >1.1 mg/dL
• Pulmonary edema

Immediate management includes:

• Hospitalization with continuous monitoring. 1, 4
• Magnesium sulfate for seizure prophylaxis: Start immediately to prevent eclamptic seizures. 2, 5, 6
• Antihypertensive therapy: If BP reaches ≥160/110 mmHg, treat within 15 minutes with IV labetalol (20 mg bolus, then 40-80 mg every 10 minutes, max 300 mg) OR oral nifedipine OR oral methyldopa. 1, 4
• Corticosteroids for fetal lung maturity at 29.6 weeks gestation (betamethasone or dexamethasone). 2, 6
• Delivery planning: Consider expectant management only in select cases before 32 weeks with close monitoring; otherwise plan prompt delivery. 4, 6

Critical Safety Considerations

• NEVER use nifedipine concomitantly with IV magnesium sulfate due to risk of severe hypotension from synergism. If magnesium is needed, use methyldopa or labetalol instead. 3
• Never reduce diastolic BP below 80 mmHg as this compromises uteroplacental perfusion and fetal development. 3, 4
• Avoid ACE inhibitors, ARBs, and direct renin inhibitors - absolutely contraindicated in pregnancy due to severe fetotoxicity. 3, 4
• Avoid atenolol - associated with fetal growth retardation. 1, 3

Management of Concurrent Anemia

• Hemoglobin of 9.4 g/dL represents mild anemia in pregnancy (normal pregnancy Hb >11 g/dL in first/third trimester, >10.5 g/dL in second trimester).
• Address anemia with oral iron supplementation while managing hypertensive disorder.
• Monitor hemoglobin closely as severe preeclampsia can cause HELLP syndrome (hemolysis, elevated liver enzymes, low platelets), which would worsen anemia. 1, 5

Common Pitfalls to Avoid

• Do not dismiss borderline BP readings (130/75 mmHg) in the presence of severe symptoms - preeclampsia can threaten mother and baby at any BP level when severe features are present. 1
• Do not wait for proteinuria to diagnose preeclampsia - cerebral or visual symptoms alone with hypertension constitute preeclampsia with severe features. 2
• Do not assume this is benign transient hypertension - the 40% progression risk and presence of neurological symptoms mandate aggressive evaluation. 1
• Do not discharge without extended BP monitoring - BP should be observed for several hours to distinguish transient from true gestational hypertension. 1