Severe Preeclampsia: Is Vasodilation Therapy with Hydralazine Dangerous for the Preterm Fetus?

ABSTRACT

Increasing experimental and clinical evidence points to a subset of severe pre-eclamptic women who are hypoyalemic with a low cardiac index and a high systemic vascular resistance, and in whom vasodilatory therapy may cause precipitate falls in maternal perfusion pressure, unless anticipated by prior correction of the hypovolemia. Since there is a paucity of adequately controlled clinical trials with appropriate definitions of hypotension or perinatal outcome, the consequences of such episodes for the preterm fetus are unknown. Epidemiologic evidence, using a logistic regression analysis model, is reviewed, which points to an association between a hypotensive episode following a commonly used drug, hydralazine, and a worse perinatal outcome in a study of severely hypertensive women delivered less than 32 weeks. An estimate of this risk, using the odds ratio, is 5.97 (95% confidence interval 1.84 to 19.35).