Hypertension, also known as high blood pressure, is a condition in which the blood vessels have persistently raised pressure. The higher the blood pressure the more work the heart must do in order to pump blood to the rest of the body.
Hypertension is the most common medical disorder in pregnancy, and this condition complicates one in ten pregnancies. Hypertensive disorders of pregnancy include chronic hypertension (i.e., hypertension diagnosed before 20 weeks of gestation), pre-eclampsia, eclampsia, and chronic hypertension with superimposed preeclampsia.
Treatment of severely increased blood pressure is widely recommended to reduce the risk of maternal complications.
This article described a study that was conducted on 2307 pregnant women with hypertension in India. Pregnant women eligible for the study had to be 18 years and above, at least 28 weeks pregnant, required pharmacological blood pressure control for severe hypertension (systolic blood pressure ≥160 mm Hg or diastolic blood pressure ≥110 mm Hg) and were able to swallow oral medications. The selected women were randomly assigned to receive oral nifedipine retard, labetalol, or methyldopa
The primary goal was to achieve blood pressure control, defined as 120–150 mm Hg systolic blood pressure and 70–100 mm Hg diastolic blood pressure within 6 h with no adverse outcomes.
The adverse outcomes they watched out for included; hypotension (systolic blood pressure <120 mm Hg, diastolic blood pressure <70 mm Hg, or both), fetal distress, caesarean section for fetal distress up to 2 hours after the end of the study period, severe headache, severe headache requiring discontinuation of the drug, or eclampsia. The study showed that women assigned to receive nifedipine retard more frequently showed tachycardia than women receiving either labetalol or methyldopa.
The frequency of neonatal admission to an intensive care unit was also significantly higher in babies born to women given nifedipine versus those on labetalol and methyldopa. Without use of additional hypertensive drugs, more women in the nifedipine and labetalol group achieved the primary blood pressure goal than women in the methyldopa group. Women assigned to receive nifedipine were more likely to achieve the blood pressure target at 6 h than those assigned to receive labetalol or methyldopa.
The study suggested the need to increase access to, and use of, oral antihypertensive medications for the treatment of severe hypertension in pregnancy.
Take home points: All three medications; nifedipine retard, labetalol, and methyldopa are effective for the initial treatment of severe hypertension in pregnancy in low-resource clinical settings. In this study, Nifedipine retard achieved blood pressure control in more pregnant women than labetalol or methyldopa.
Written by: Iboro Udoete, MD.
T. Easterling, S. Mundle, H. Bracken, S. Parvekar, S. Mool, L. Magee, P. von Dadelszen, T. Shochet, B. Winikoff: Oral antihypertensive regimens nifedipine retard, labetalol, and methyldopa for management of severe hypertension in pregnancy: an open-label, randomized controlled trial: 2019: 10.1016.https://pubmed.ncbi.nlm.nih.gov/31378394/
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