Premature newborn infants may have impaired lung function as a result of their prematurity. When this occurs, the newborns show poor oxygen and carbon dioxide exchange and difficulty in breathing. The reason for these symptoms is due in part to the lack of special chemicals in the lungs, called phospholipids or surfactant. The lack of these special chemicals causes the babies lung to be difficult to ventilate. Treatment of this condition can require placing an artificial airway (endotracheal tube) into the babies windpipe (intubation) and use of a breathing machine (ventilator). In addition, physicians frequently give these special chemicals (phospholipid) through the childs airway. There are several different types of phospholipids available for this treatment in newborns but very limited amount of studies have been done to examine differences in the ability to ventilate between the various types of surfactant. The investigators propose to examine immediate changes in ability to ventilate (dynamic compliance) at specific time intervals after administration of either type of surfactant; Curosurf or Survanta.