What is the diagnosis and management of pre-eclampsia (Pregnancy-induced hypertension)?

From the Guidelines

Pre-eclampsia is a serious pregnancy complication that requires prompt medical attention, and its management depends on the severity of the condition and gestational age, with the definitive treatment being delivery of the baby and placenta, as recommended by the ISSHP guidelines 1.

Diagnosis and Management

The diagnosis of pre-eclampsia involves assessing blood pressure, proteinuria, and other maternal and fetal factors. According to the ISSHP guidelines, blood pressure requires urgent treatment in a monitored setting when severe (>160/110 mm Hg), and acceptable agents for this include oral nifedipine or intravenous labetalol or hydralazine 1.

• Blood pressure control is crucial, with a target diastolic blood pressure of 85 mm Hg, and acceptable agents include oral methyldopa, labetalol, oxprenolol, and nifedipine, with second or third line agents hydralazine and prazosin 1.
• Women with pre-eclampsia should be assessed in hospital when first diagnosed, and thereafter, some may be managed as outpatients once it is established that their condition is stable and they can be relied on to report problems and monitor their blood pressure 1.
• Magnesium sulfate should be administered for convulsion prophylaxis in women with pre-eclampsia who have proteinuria and severe hypertension, or hypertension with neurological signs or symptoms 1.

Monitoring and Delivery

• Fetal monitoring in pre-eclampsia should include an initial assessment to confirm fetal well-being, and serial fetal surveillance with ultrasound should be performed in the presence of fetal growth restriction 1.
• Maternal monitoring in pre-eclampsia should include blood pressure monitoring, repeated assessments for proteinuria, clinical assessment including clonus, and twice weekly blood tests for hemoglobin, platelet count, liver and renal function, including uric acid 1.
• Women with pre-eclampsia should be delivered if they have reached 37 weeks’ gestation or if they develop any of the following: repeated episodes of severe hypertension, progressive thrombocytopenia, progressively abnormal renal or liver enzyme tests, pulmonary edema, abnormal neurological features, or nonreassuring fetal status 1.

Key Recommendations

• The ISSHP guidelines recommend that women with pre-eclampsia should be managed based on the severity of the condition and gestational age, with the goal of reducing maternal and fetal morbidity and mortality 1.
• Close monitoring of maternal blood pressure, urine protein, liver and kidney function, and fetal well-being is essential in the management of pre-eclampsia 1.
• Women with a history of pre-eclampsia have an increased risk in future pregnancies and should receive preventive low-dose aspirin (81-150mg daily) starting at 12-16 weeks gestation in subsequent pregnancies 1.

From the Research

Diagnosis of Pre-eclampsia

• Pre-eclampsia is defined as the association of pregnancy-induced hypertension and proteinuria of 300 mg/24h or more after 20 weeks gestation 2
• Hypertensive disorders of pregnancy are one of the leading causes of peripartum morbidity and mortality globally 3
• Pre-eclampsia is characterized by blood pressure greater than 140/90 mmHg in the second half of pregnancy 4

Management of Pre-eclampsia

• The mainstay of the management of severe pre-eclampsia is early referral, stabilization of the mother with antihypertensive therapy and anticonvulsants if required, full assessment of the mother and the baby, and delivery on the best day in the best way 5
• Management of severe pre-eclampsia includes identification of high-risk patients, optimisation of antenatal care, early intervention and the identification and early management of complications 3
• Oral anti-hypertensive agents, including labetalol, nifedipine and methyldopa, should be tried first, and if they fail to adequately control blood pressure, intravenous anti-hypertensives such as labetalol, hydralazine and glyceryl trinitrate should be considered 3
• Magnesium sulphate should be considered early to prevent seizures 3, 2
• Delivery of the baby is the definitive management of severe pre-eclampsia 3, 5

Expectant Management of Pre-eclampsia

• Expectant management of early onset, severe pre-eclampsia can diminish and limit the impact of serious maternal complications, and valuable time to prolong the pregnancy and improve neonatal outcome can be gained 6
• Careful noninvasive management of early onset, severe pre-eclampsia in a tertiary centre can prolong pregnancies by a mean of 11 days before delivery 6

Prevention of Pre-eclampsia

• Preventive treatment of preeclampsia consists essentially of low dose aspirin, which decreases the risk of recurrence of preeclampsia by 10 to 15%, of prematurity by 8% and of perinatal mortality by 14% 2