Effects of Transitional Circulation in ELBW Infants

The study team will use monitoring methods normally used in the NICU (physical exams, echocardiograms, and ECG) and some new monitoring methods (Near-infrared spectroscopy or NIRS) to find out all the changes that a baby's heart and lungs go through during the first week after delivery. In addition, blood samples will be taken to assess lactate, troponin, and creatinine levels.