What are the management guidelines for a pregnant woman with hypertension, preeclampsia, or eclampsia?

Management of Hypertension, Preeclampsia, and Eclampsia in Pregnancy

All pregnant women with severe hypertension (≥160/110 mmHg) require immediate treatment in a monitored setting with IV labetalol, IV hydralazine, or oral nifedipine, and those with severe preeclampsia must receive magnesium sulfate for seizure prophylaxis followed by expedited delivery after maternal stabilization. 1, 2

Immediate Management of Severe Hypertension (≥160/110 mmHg)

Severe hypertension requires urgent treatment within 15 minutes to prevent maternal cerebral hemorrhage. 1, 3

First-Line Antihypertensive Agents:

• IV labetalol: 20 mg IV bolus, then 40 mg after 10 minutes, then 80 mg every 10 minutes (maximum cumulative dose 220 mg) 2, 3
• IV hydralazine: 5-10 mg IV every 20 minutes as needed 3, 4
• Oral nifedipine: Acceptable alternative if IV agents unavailable 1

Blood Pressure Targets:

• Target diastolic BP: 85 mmHg 1
• Target systolic BP: 110-140 mmHg 1, 2
• Minimum acceptable: <160/105 mmHg 2, 3
• Goal: Decrease mean BP by 15-25% to maintain uteroplacental perfusion while preventing maternal complications 2

Critical Medication Warnings:

• Avoid short-acting oral nifedipine when combined with magnesium sulfate due to risk of uncontrolled hypotension and fetal compromise 2
• Sodium nitroprusside only as last resort due to risk of fetal cyanide poisoning 2, 4
• ACE inhibitors, ARBs, and direct renin inhibitors are absolutely contraindicated due to severe fetotoxicity 2
• Diuretics are contraindicated as they further reduce plasma volume which is already contracted in preeclampsia 2, 3

Management of Non-Severe Hypertension (140-159/90-109 mmHg)

Blood pressures consistently ≥140/90 mmHg in clinic (or ≥135/85 mmHg at home) should be treated to reduce the likelihood of developing severe hypertension and complications. 1

Acceptable Oral Agents:

• First-line: Methyldopa, labetalol, oxprenolol, nifedipine 1
• Second/third-line: Hydralazine, prazosin 1
• Reduce or cease antihypertensives if diastolic BP falls <80 mmHg 1

Preeclampsia-Specific Management

Initial Assessment and Hospitalization:

All women with newly diagnosed preeclampsia must be assessed in hospital initially; stable patients may transition to outpatient management only if they can reliably report problems and monitor BP. 1

Magnesium Sulfate for Seizure Prophylaxis:

Administer magnesium sulfate immediately to all patients with:

• Preeclampsia with proteinuria AND severe hypertension 1
• Any hypertension with neurological signs or symptoms (severe headache, visual disturbances) 1, 2
• All cases of severe preeclampsia 2, 5

Dosing regimen: 2, 3

• Loading dose: 4-5 g IV over 5 minutes (diluted in 250 mL of 5% dextrose or 0.9% normal saline)
• Maintenance: 1-2 g/hour continuous IV infusion
• Continue until delivery and for at least 24 hours postpartum 1

In low-resource settings: 4 g IV or 10 g IM loading dose, followed by 5 g IM every 4 hours 1

Monitoring Requirements for Magnesium Sulfate:

• Hourly urine output via Foley catheter: target ≥100 mL/4 hours (or >35 mL/hour) 2, 3
• Deep tendon reflexes before each dose to monitor for toxicity 2
• Respiratory rate monitoring (magnesium toxicity causes respiratory depression) 2
• Oxygen saturation on room air (maternal early warning if <95%) 2

Comprehensive Maternal Monitoring in Preeclampsia

Laboratory Assessment:

Obtain at least twice weekly (more frequently with clinical deterioration): 1

• Complete blood count (hemoglobin, platelet count)
• Liver transaminases (AST/ALT)
• Creatinine
• Uric acid (associated with worse maternal and fetal outcomes) 1

Clinical Monitoring:

• Continuous BP monitoring 1, 5
• Repeated assessments for proteinuria if not already present 1
• Clinical assessment including clonus 1
• Assessment for maternal agitation, confusion, or unresponsiveness 2
• Monitor for non-remitting headache and shortness of breath 2

Proteinuria Assessment:

Screen with automated dipstick urinalysis; if positive, quantify with urine protein/creatinine ratio. 1

• Abnormal ratio: ≥30 mg/mmol (0.3 mg/mg) 1, 3
• Alternative: ≥300 mg/24 hours or ≥1+ on dipstick 3

Fetal Monitoring in Preeclampsia

Initial Assessment:

Perform ultrasound at diagnosis to assess: 1

• Fetal biometry
• Amniotic fluid volume
• Umbilical artery Doppler

Serial Surveillance:

• Repeat ultrasound every 2 weeks if initial assessment normal 1, 2
• More frequent monitoring (amniotic fluid and Doppler) if fetal growth restriction present 1, 2
• Continuous fetal heart rate monitoring 2, 5

Delivery Timing: Gestational Age-Based Algorithm

≥37 Weeks:

Deliver immediately after maternal stabilization, regardless of severity. 1, 3

• Induction of labor is associated with improved maternal outcome 2
• Do not delay delivery based on non-reactive NST 3

34-37 Weeks:

• Without severe features: Expectant management with close monitoring is appropriate 5, 3
• With severe features: Deliver after maternal stabilization 3

<34 Weeks:

Conservative expectant management at a center with Maternal-Fetal Medicine expertise, unless maternal or fetal deterioration occurs. 2, 3

<24 Weeks:

Expectant management is associated with high maternal morbidity with limited perinatal benefit—counsel regarding pregnancy termination. 2

Absolute Indications for Immediate Delivery (Any Gestational Age)

Deliver immediately regardless of gestational age if any of the following develop: 1, 2

• Inability to control BP despite ≥3 classes of antihypertensives in appropriate doses 1, 2
• Progressive thrombocytopenia 1, 2
• Progressively abnormal renal or liver enzyme tests 1, 2
• Pulmonary edema 1, 2
• Severe intractable headache, repeated visual scotomata, or convulsions 1, 2
• Non-reassuring fetal status 1, 2
• Maternal oxygen saturation deterioration (<90%) 2, 3
• Placental abruption 2, 3

HELLP Syndrome Recognition and Management

HELLP syndrome is defined by hemolysis, elevated liver enzymes, and low platelets, with a maternal mortality rate of 3.4%. 2, 3

Hallmark Symptoms:

• Epigastric or right upper quadrant pain (suggests hepatic capsule distension) 2, 3
• Renal dysfunction with oliguria and elevated creatinine 2
• Thrombocytopenia and elevated liver enzymes 2

Critical Considerations:

• Monitor glucose intraoperatively as severe hypoglycemia can occur 2, 3
• Immediate delivery is indicated after maternal stabilization 3

Management of Pulmonary Edema

Drug of choice: IV nitroglycerin (glycerol trinitrate) 2, 3

• Starting dose: 5 mcg/min
• Gradually increase every 3-5 minutes to maximum 100 mcg/min 2, 3
• Plasma volume expansion is NOT recommended routinely 1, 2, 3

Eclampsia Management

Eclampsia (seizures in the setting of preeclampsia) requires immediate magnesium sulfate administration and expedited delivery after maternal stabilization. 2, 5

• Magnesium sulfate is the definitive treatment for eclamptic seizures 6
• Administer loading dose immediately, followed by maintenance infusion 2
• Deliver after maternal stabilization regardless of gestational age 2

Gestational Hypertension Considerations

At least 25% of gestational hypertension cases will progress to preeclampsia; therefore, it is not a benign disorder. 1

Management:

• Hospital assessment required if severe hypertension (≥160/110 mmHg) or preeclampsia develops 1
• No specific test can predict which cases will progress to preeclampsia at time of diagnosis 1
• Risk is highest among those presenting <34 weeks 1
• Optimal delivery timing: 38-39 weeks for gestational hypertension without preeclampsia features (based on retrospective data, awaiting randomized trial confirmation) 1

Prevention Strategies

Low-dose aspirin (75-162 mg/day) starting in the first trimester until labor or 36-37 weeks reduces risk of preterm preeclampsia in high-risk women. 1, 6

• Screening with maternal risk factors, BP, placental growth factor (PlGF), and uterine artery Doppler can identify candidates 1
• Calcium supplementation recommended for prevention 6

Critical Pitfalls to Avoid

Do not underestimate disease severity—all preeclampsia cases should be treated as potentially severe, as rapid progression to life-threatening complications can occur even with initially mild presentations. 1, 3

• Blood pressure alone is not a reliable indicator of disease severity—serious organ dysfunction can develop at relatively mild levels of hypertension 5, 3
• Do not use serum uric acid or level of proteinuria as indication for delivery 2, 3
• Do not attempt to diagnose "mild versus severe" preeclampsia clinically—all cases may become emergencies rapidly 1, 2
• Do not reduce antihypertensives if diastolic BP falls <80 mmHg 2, 3
• Home BP monitoring is mandatory in white-coat hypertension management 1

Transfer and Coordination

Medicalized transport to a specialized obstetric center should be systematically considered for all patients with severe preeclampsia. 2

Before Transfer:

• Coordinate with obstetric and anesthetic-intensivist teams at receiving facility 2
• Initiate magnesium sulfate and blood pressure control prior to transport 2
• Involve emergency medical assistance service regulating doctor 2