Cardiac Output, High

The purpose of the research is to characterize the effect of labetalol, atenolol, and nifedipine on maternal hemodynamics early in pregnancy. Patients will be given medication based on their hemodynamics and asked to return for a repeat measurement.

This is an observational study in newborn term and preterm infants. The study will validate if non-invasive continuous cardiac output monitoring is feasible in newborn infants, if normative values can be constructed and what is the effect of fluid boluses and inotropes on cardiac output and peripheral vascular resistance.