The purpose of this study is to conduct a prospective study of all congenital diaphragmatic hernia (CDH) neonates managed at the University of Utah newborn intensive care unit (NICU) and Primary Children's Hospital NICU that required mechanical ventilation at birth. As both high frequency jet ventilation (HFJV) and high frequency oscillatory ventilation (HFOV) are standard approaches to ventilatory support of all neonates including CDH, CDH infants will be randomized at the time of birth or admission to either HFJV or HFOV as initial ventilator mode, stratified by position of the liver in the abdomen or thorax (if known) by 24 hours of age. Measures of oxygenation, ventilation and hemodynamics of the CDH cohort managed on HFOV compared to those on HFJV.