Drugs for rapid treatment of very high blood pressure during pregnancy

Abstract

Background: Very high blood pressure during pregnancy poses a serious threat to women and their fetuses. The use of drugs to lower blood pressure may reduce this risk.

Objectives: The objective of this review was to compare different antihypertensive drugs used for rapid treatment of severe hypertension during pregnancy.

Search strategy: We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register.

Studies: All randomised trials. Quasi random designs were excluded.

Participants: Women with severe hypertension during pregnancy. Women postpartum at trial entry were excluded.

Interventions: Comparisons of one antihypertensive agent with another.

Outcomes: For the women: blood pressure control, eclampsia, serious maternal morbidity (such as kidney failure and liver failure), Caesarean section, and use of health service resources (such as admission to hospital or intensive care unit). For the baby: death, serious neonatal morbidity, infant and child development, and use of health service resources (such as admission to a special care nursery).

Data collection and analysis: Data were extracted independently by two reviewers to assess eligibility and describe the trial characteristics, and by one reviewer for the meta-analyses. Discrepancies were resolved by discussion. There was no blinding of authorship or results. Whenever possible, unpublished data were sought from investigators.

Main results: Thirteen of the 14 trials included in this review were small (range 19-627 women). Of the eight comparisons, five included hydralazine. Diazoxide given as 75mg bolus injections appears to be associated with profound hypotension requiring treatment, and ketanserin is less effective than hydralazine at reducing blood pressure. There is no other evidence that any one of the other antihypertensive agents is better than another for women with severe hypertension during pregnancy.

Reviewer's conclusions: Until better evidence is available, the choice of antihypertensive should depend on the experience and familiarity of an individual clinician with a particular drug, and on what is known about adverse maternal and fetal side-effects. Exceptions are diazoxide and ketanserin, which are probably not good choices.