Non-Invasive Hemodynamic Assessment in Term Preeclamptic Women Using Bio-reactance
Abstract Number: 8
Abstract Type: Original Research
Background: Bio-reactance technology represents a new advance in non-invasive hemodynamic assessment, but has not yet been evaluated in pregnant women. This pilot study was designed to assess the feasibility of a new non-invasive cardiac output monitor (NICOM) based on bio-reactance, and to compare the hemodynamic profiles of healthy and mildly preeclamptic pregnant women at term, as well as those of non-pregnant controls.
Methods: With REB approval and written informed consent, this prospective study included healthy non-laboring term pregnant women at term (Preg, n=10), mildly preeclamptic non-laboring pregnant women at term (PregPE, n=10), and healthy non-pregnant female controls (NonPreg, n=10). With the subjects in the semi left lateral position, 4 electrodes of the NICOM device were applied to their chest wall, followed by a 15-minute rest period. Hemodynamic variables, including the systolic (SBP), diastolic (DPB) and mean arterial (MAP) pressures, as well as the heart rate (HR), stroke volume (SV), total peripheral resistance (TPR), cardiac output (CO), cardiac power output (CPO), and ventricular ejection time (VET), were monitored for 15 minutes; subsequently a passive leg raising (PLR) test was performed, and the hemodynamic variables were measured again..
Results: The Preg and NonPreg groups showed similar hemodynamic profiles, except for a shorter VET in the Preg group. The SBP, DBP and MAP, as well the CPO, were significantly higher in the PregPE group when compared to both the Preg and NonPreg groups. The HR, CO, and TPR were significantly higher, and the VET was significantly shorter, in the PregPE group when compared to the NonPreg group. The PLR test did not change the baseline hemodynamic variables in any of the groups.
Conclusion: The NICOM device was simple to use, and provided clear and consistent monitoring signals. The output identified distinct hemodymamic profiles in the three groups studied that are consistent with the findings of more invasive existing methods. Further evaluation is warranted to define the role of the NICOM in more severe preeclampsia and in other high risk obstetric situations.