Contributor: Sharon Keiser, MD
Date: January 2021
Definitions, classification and diagnostic criteria:
Chronic hypertension (CHTN)- SBP>140 or DBP>90 on 2 separate occasions at least 4 hours apart, diagnosed prior to pregnancy or before 20 weeks gestation or persisting longer than 12 weeks postpartum.
Gestational hypertension (GHTN)- SBP>140 or DBP>90 on two separate occasions at least 4 hours apart after 20 weeks gestation in women with previously normal blood pressure.
Severe GHTN/Preeclampsia with severe features– (SBP>160 or DBP>110) on two separate occasions at least 4 hours (unless antihypertensive therapy is initiated before this time).
Preeclampsia- GHTN plus new onset proteinuria, defined as either >300 mg protein on 24 hour urine or P:C ratio > 0.3 or 2+ protein on dipstick (only if other quantitative methods not available). The diagnosis of preeclampsia is not dependent on proteinuria. Without proteinuria, the diagnosis is considered with new-onset HTN and the onset of any of the following severe features:
- Persistent cerebral or visual disturbances (HA, scotomata, hyperreflexia, seizure)
- Pulmonary edema
- Severe RUQ pain or epigastric pain (without other diagnosis)
- Thrombocytopenia (platelets <100k/uL)
- Elevated LFTs (2x upper limits of normal)
- Serum creatinine >1.1mg/dL or doubling of creatinine without renal disease
Preeclampsia with severe features– Preeclampsia with SBP>160 or DBP>110 on two occasions at least 4 hours apart (unless hypertensive therapy is initiated before this time) or any severe features listed above are present.
CHTN with superimposed preeclampsia– Preeclampsia in a woman with a diagnosis of hypertension prior to pregnancy of diagnosed before 20 weeks.
Eclampsia– New-onset tonic-clonic, focal or multifocal seizures in the absence of other causative conditions such as epilepsy or drug use.
Risk factors for preeclampsia
- Preeclampsia in previous pregnancy
- Gestational or pregestational diabetes
- Prepregnancy BMI >30
- Pregnancy resulting from ART
- Multifetal gestations
- Antiphospholipid syndrome
- Renal disease
- Obstructive sleep apnea
See guideline for low dose ASA use in these high risk conditions to decrease the risk for preeclampsia.
Preeclampsia without severe features & GHTN:
Antepartum Management <37 weeks
- Outpatient management if complaint OR inpatient management if adherence to follow up visit is concern
- Preeclampsia labs weekly- CBC, CMP,LDH
- Twice weekly antenatal testing and serial growth scans
- Consider BMS unless contraindicated
- The addition of antihypertensive medication are not recommended. No improvement in perinatal outcome is noted and severe disease may be masked.
- Delivery at 37 weeks if not indicated sooner
Antepartum > 37 weeks gestation– DELIVER
- Continuous FHR monitoring
- HELLP labs every 12 hours
- Use of MgSO4 for seizure prophylaxis is recommended if severe features develop; consideration for use in GHTN and preeclampsia without severe features can be individualized
- Monitor for development of severe features
- Mode of delivery determined by routine obstetric indications
- Closely monitor BP, UOP and symptoms.
- Antihypertensive medications to keep SBP <150; DBP <100
- All patients with these diagnoses should be given discharge instructions for s/s of worsening hypertensive disease and seen in 3-7 days postpartum in outpatient setting for BP check.
- Contraception- estrogen containing contraception should not be given to any patient with a hypertensive disorder of pregnancy until hypertension is controlled/resolved. Consider LARC, depo-provera or progesterone only pills.
- Counsel about low-dose ASA as prevention in subsequent pregnancies.
Preeclampsia with Severe Features
Antepartum Management <23 weeks gestation (or EFW <400 grams or umbilical cord Doppler with persistent REDF)- DELIVER
Antepartum Management 23-34 weeks gestation
- Inpatient hospitalization until delivery
- BMZ if appropriate; do not delay delivery for BMZ maturity if maternal or fetal status is deteriorating
- Initiate MgSO4 during initial assessment period if severe features are present; may discontinue at steroid maturity if managing conservatively
- Serial preeclampsia labs and blood pressure monitoring
- Daily NST with weekly BPP; growth ultrasound every 3 weeks until delivery
- Daily weights
- Consider conservative management if:
- Maternal and fetal status are reassuring AND patient agrees/understands risk
- Diagnosis is made by BP criteria only AND antihypertensive medication keeps SBP<160 and DBP<110. Medications include nifedipine XL p.o. (max 120 mg/day), labetalol p.o. every 6 to 8 hours (max 2400 mg/day), hydralazine p.o. (max 300 mg/day).
- Conservative management contraindicated with any of the following:
- Maternal desire for delivery
- Oliguria (UOP less than 30 cc/hour x4 hours) or renal failure (Cr > 1.1 mg/dL or twice baseline)
- Neurologic symptoms
- Nonreassuring fetal assessment or fetal death
- Vaginal bleeding or other signs of abruption
- Uncontrolled severe range BPs
- Development of HELLP syndrome
- Pulmonary edema or myocardial infarction
- IUGR (relative contraindication)
Antepartum Management >34 weeks gestation- Deliver giving BMZ during induction (do not delay delivery for BMZ)
- Continuous fetal monitoring
- Preeclampsia labs every 12 hours or more frequent if indicated (CBC, CMP, LDH, +/- uric acid)
- Initiate magnesium sulfate (see table) with induction of labor or cesarean
- Strict I/Os
- Monitor respirations, DTRs, maternal mental status every 2 hours
- IOL may be considered for pregnancies greater than 30 weeks or earlier, if favorable cervix; cesarean delivery may be considered with nonreassuring fetal status or unfavorable cervix prior to 30 weeks
- Antihypertensives should be utilized to keep SBP<160 and DBP<110. Oral medications as mentioned previously nifedipine, labetalol, hydralazine. See table for IV administration of antihypertensive medications.
- Regional anesthesia is preferred. General anesthesia carries higher risk of aspiration, failed induction, or stroke. Neuraxial anesthesia is contraindicated in the presence of a coagulopathy. No consensus on lower limit for platelet count and neuro axial anesthesia (risk of hematoma is low in patients with platelet count greater than 70K). Continue MgSO4 during cesarean.
- Continue MgSO4 for 24 hours (or 24 hours from last seizure activity if applicable)
- Strict I/Os and daily weights for entire postpartum hospital course
- Maintain BPs < 150 systolic and <100 diastolic. Utilize–nifedipine XL p.o. (max 120 mg/day), labetalol p.o. every 8-12 hours (max 2400 mg/day), HCTZ 12.5 to 50 mg/day (may reduce milk volume)
- All patients must be evaluated within 1 week after hospital discharge for a blood pressure check
- Contraception–estrogen-containing contraception should not be given to any patient with a hypertensive disorder of pregnancy until hypertension has resolved; consider progesterone only pills, Depo-Provera, or LARC
- Counsel regarding low-dose aspirin as a preventative and subsequent pregnancies
- Call for help in alert anesthesia
- Prevent maternal injury and aspiration
- Place in lateral decubitus position
- Monitor vital signs
- Administer oxygen
- Initiate magnesium sulfate for seizure prophylaxis after seizure activity has stopped (See table)
- Reduce blood pressure (range for SBP 140 to <160 and DBP 90 to <110)
- Initiate a course of betamethasone if appropriate
- Fetal monitoring (after seizure activity has stopped). During/immediately after eclamptic seizures, FHRT may show prolonged decelerations and/or bradycardia which usually resolve after 10 minutes or correction of maternal hypoxemia
- Move towards delivery (eclampsia is not an indication for cesarean section)
- Continue MgSO4 for 24 hours after the resolution of seizure activity
- Additional seizure activity (occurs in approximately 10% of patients). Give an additional 2 to 4 g of MgSO4 IV over 5 min. In cases refractory to magnesium (still having seizures 20 minutes after bolus or greater than 2 recurrences), give sodium amobarbital (250 mg IV), thiopental or phenytoin. Consider head CT/MRI.
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