 While the baby is on CPAP, we will start monitoring oxygen saturation by applying NIRS sensors to the forehead and the abdomen. After 3 hours we will do echocardiography ultrasound of the heartto see any changes that might happen to the heart and blood vessels while the baby is on CPAP. Then, using the same machine, we will change the mode of respiratory support to TrPA. After another three hours, we will do another echocardiography ultrasound of the heart, then we will stop NIRS monitoring and change the mode of respiratory support back to CPAP. 