Cardiac Output Changes With Uterine Displacement

There is currently little information regarding the hemodynamic differences in uterine displacement techniques. Previous studies examining the hemodynamic effects of uterine displacement maneuvers have focused on incidence of hypotension and use of ephedrine. Noninvasive cardiac output monitoring (NICOM) and transthoracic echocardiography (TTE) are becoming popular techniques in anesthesiology because they can provide noninvasive, valid, and precise hemodynamic data.There has been no study specifically examining the hemodynamic differences between the uterine displacement techniques using NICOM or TTE. While all three uterine displacement techniques are recommended, whether one technique may maximize maternal cardiac output is currently unknown.

Inclusion Criteria: 1. Healthy ASA physical status I-II 2. Term parturient Exclusion Criteria: 1. Woman in labor 2. Presence of maternal medical conditions affecting the cardiovascular system (including preeclampsia, gestational hypertension) 3. Fetal anomaly or intrauterine growth restriction (\< 25th percentile) 4. Maternal renal or endocrine disease