Outcomes of Pregnancies at Risk for Hypertensive Complications Managed Using Impedance Cardiography

Abstract

We assessed the effect of antihypertensive therapy guided by impedance cardiography on maternal and fetal outcomes in pregnancies at risk for hypertensive complications. We performed a retrospective review of the outcomes of 318 singleton pregnancies with chronic hypertension or prior preterm delivery due to preeclampsia whose antihypertensive therapy was guided by impedance cardiography. Hemodynamic subsets were compared using analysis of variance. Impedance cardiography was used to evaluate cardiac output and total peripheral resistance starting at less than 24 weeks. All patients received atenolol; 24% required additional therapy with a vasodilator. The mean gestational age at delivery was 37 +/- 2 weeks. Preeclampsia developed in 14%. The incidence of birth weight less than the 10th percentile was 10%. There were no perinatal deaths, and 75% of the infants spent <3 days in the hospital. Hyperdynamic patients had less preeclampsia, less severe preeclampsia, fewer deliveries <34 weeks, and fewer neonatal intensive care unit days compared with those requiring a vasodilator. Antihypertensive therapy guided by hemodynamic information results in pregnancies delivering at or near term, little preeclampsia, and no increase in growth restriction. Hyperdynamic patients have better outcomes than patients with increased total peripheral resistance.