Prior to discharge, your baby's blood oxygen (or "oxygen saturation") will be measured with a pulse oximeter. This non-invasive procedure is being done on every baby to check for heart disease in otherwise well-appearing newborns. This is done by attaching a tiny red light to the baby's hand, foot, or wrist by a piece of adhesive elastic. A cord travels from the light to a machine that shows the amount of oxygen being carried by red blood cells in the baby's body. This may be a part of the cardiorespiratory monitor or a separate monitor. If the oxygen saturation level becomes less than normal, then an alarm will sound telling the nursing staff. If the cord becomes loose for any reason or the baby is moving around a lot, then this will set off the alarm. The test will be repeated two more times. If the number is still low (below or equal to 94%), then the pediatrician will order blood pressures, an EKG, CXR, and an echocardiogram for your baby. A pediatric cardiologist will then need to see your baby, too, before discharge to determine further evaluation outpatient.