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

From the Guidelines

Pre-eclampsia should be managed with urgent treatment in a monitored setting when severe (>160/110 mm Hg), and antihypertensive medications like labetalol, nifedipine, or methyldopa should be used to control blood pressure, aiming to keep it below 140/90 mmHg, as recommended by the ISSHP guidelines 1. The diagnosis of pre-eclampsia is based on the presence of high blood pressure and organ damage, typically affecting the liver and kidneys, after 20 weeks of pregnancy.

• Key features of pre-eclampsia include:
  • High blood pressure
  • Proteinuria
  • Organ damage (e.g., liver and kidneys)
• Management of pre-eclampsia depends on the severity of the condition and gestational age.
• For mild pre-eclampsia, close monitoring with regular blood pressure checks, urine tests for protein, and blood tests to assess organ function may be sufficient.
• Antihypertensive medications like labetalol (starting at 100-200mg twice daily), nifedipine (10-20mg three times daily), or methyldopa (250-500mg three times daily) are commonly used to control blood pressure, aiming to keep it below 140/90 mmHg, as recommended by the ISSHP guidelines 1.
• For severe pre-eclampsia, especially with features of impending eclampsia, magnesium sulfate is administered intravenously (4-6g loading dose over 15-20 minutes, followed by 1-2g/hour maintenance) to prevent seizures, as recommended by the ISSHP guidelines 1.
• Corticosteroids (betamethasone 12mg intramuscularly, two doses 24 hours apart) may be given to accelerate fetal lung maturity if preterm delivery is anticipated.
• Women with pre-eclampsia require close postpartum monitoring as complications can still occur after delivery, and they face increased risk of cardiovascular disease later in life, as noted in the ISSHP guidelines 1. The ISSHP guidelines recommend that 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.

From the Research

Diagnosis of Pre-eclampsia

• Pre-eclampsia is characterized by blood pressure greater than 140/90 mmHg in the second half of pregnancy 2
• The disease is often presenting as new-onset hypertension and proteinuria during the third trimester 3
• Hypertensive disorders of pregnancy, including pre-eclampsia, are associated with a spectrum of severity, ranging from mild pregnancy-induced hypertension to eclampsia 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
• The current clinical management of pre-eclampsia includes hydralazine with labetalol and magnesium sulfate to slow disease progression and prevent maternal seizure, and hopefully prolong the pregnancy 2
• 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 should be considered 4
• Expectant or outpatient management of pre-eclampsia before 34 weeks may be associated with increased stillbirth risk, but it can prolong the pregnancy by over 11 days 6

Complications and Risks

• Severe pre-eclampsia is a life-threatening multisystem disease associated with eclampsia, HELLP syndrome, acute kidney injury, pulmonary oedema, placental abruption, and intrauterine fetal death 4
• The main cause of death in pre-eclampsia is now pulmonary oedema, with renal failure a rare complication 5
• Pre-eclampsia is a major contributor to preterm and low birth weight babies, and it is the leading cause for preterm labor and infant mortality and morbidity 2
• There are substantial long-term cardiovascular and metabolic risks to mothers and children associated with gestational hypertensive disorders, in particular, preterm pre-eclampsia 3