What is the recommended treatment for hypertension in antepartum preeclampsia with severe features?

From the Guidelines

For antepartum preeclampsia with severe features, blood pressure should be treated promptly with antihypertensive medications when systolic blood pressure reaches or exceeds 160 mmHg or when diastolic blood pressure reaches or exceeds 110 mmHg, with the goal of maintaining blood pressure below 160/110 mmHg but above 120/80 mmHg to preserve uteroplacental perfusion, as recommended by the most recent guidelines 1.

Key Management Points

• First-line intravenous options for severe hypertension include labetalol or hydralazine, with oral nifedipine as an alternative 1.
• For mild range hypertension (140-159/90-109 mmHg), oral medications like labetalol, nifedipine, or methyldopa are appropriate 1.
• Prompt treatment of severe hypertension is crucial to prevent maternal complications like stroke, while maintaining adequate blood pressure ensures sufficient blood flow to the placenta.
• ACE inhibitors and angiotensin receptor blockers should be avoided during pregnancy due to fetal risks.

Monitoring and Delivery

• Women with preeclampsia 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 BP 1.
• Women with preeclampsia who have proteinuria and severe hypertension, or hypertension with neurological signs or symptoms, should receive magnesium sulfate for convulsion prophylaxis 1.
• Delivery should be considered if the patient has reached 37 weeks’ gestation or develops 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 FDA Drug Label

The capacity of labetalol to block alpha-receptors in man has been demonstrated by attenuation of the pressor effect of phenylephrine and by a significant reduction of the pressor response caused by immersing the hand in ice-cold water ("cold-pressor test") Labetalol beta1-receptor blockade in man was demonstrated by a small decrease in the resting heart rate, attenuation of tachycardia produced by isoproterenol or exercise, and by attenuation of the reflex tachycardia to the hypotension produced by amyl nitrite. Beta2-receptor blockade was demonstrated by inhibition of the isoproterenol-induced fall in diastolic blood pressure Both the alpha- and beta-blocking actions of orally administered labetalol HCl contribute to a decrease in blood pressure in hypertensive patients. In a clinical pharmacologic study in severe hypertensives, an initial 0. 25 mg/kg injection of labetalol HCl, administered to patients in the supine position, decreased blood pressure by an average of 11/7 mmHg.

The recommended treatment for hypertension in antepartum preeclampsia with severe features is labetalol (IV), with an initial dose of 0.25 mg/kg administered to patients in the supine position, which can be increased as needed to achieve the desired effect 2.

From the Research

Recommended Treatment for Hypertension in Antepartum Preeclampsia with Severe Features

The recommended treatment for hypertension in antepartum preeclampsia with severe features includes:

• Oral anti-hypertensive agents, such as labetalol, nifedipine, and methyldopa, as the first line of treatment 3
• Intravenous anti-hypertensives, including labetalol, hydralazine, and glyceryl trinitrate, if oral agents fail to control blood pressure 3
• Magnesium sulphate to prevent seizures 3

Comparison of Anti-Hypertensive Agents

Studies have compared the efficacy of different anti-hypertensive agents in managing severe preeclampsia, including:

• Labetalol and hydralazine, with labetalol showing greater efficacy in reducing systolic and diastolic blood pressure 4
• Nifedipine, labetalol, and methyldopa, with nifedipine achieving treatment success in most women, similar to hydralazine and labetalol 5
• Nifedipine and hydralazine, with nifedipine showing effective control of blood pressure in 95.8% of subjects, compared to 68% with hydralazine 6

Antihypertensive Therapy in the Postpartum Period

In the postpartum period, various antihypertensive drug therapies are used to manage pre-eclampsia with severe features, including:

• Nifedipine as the commonest rapid-acting agent used for severe hypertension 7
• Alpha-methyldopa as the commonest single long-acting agent used prepartum and postpartum 7
• Combination therapies, such as alpha-methyldopa and amlodipine, which are commonly used in the postpartum period 7