Congenital diaphragmatic hernia is a rare entity in childhood carrying a high mortality rate of 30% to 50%. Ipsilateral pulmonary hypoplasia, increased pulmonary vascular resistance, and potential cardiac failure complicate early postnatal life. Surgical correction can either be performed on the first day of life or be deferred to a time after stabilization of the infant. Our patient presented with a left-sided Bochdalek's hernia containing large and small bowel. She required intubation and resuscitation on day 1 of life, and surgical repair had to be postponed. Further respiratory deterioration required commencement of inhaled nitric oxide and high-frequency ventilation. Pulmonary artery pressure rose to suprasystemic level. Closure of the ductus arteriosus on day 8 resulted in imminent right-sided heart failure. Commencement of alprostadil (prostaglandin E1) reopened the ductus and stabilized the patient. Surgical repair was successful 3 days later. Alprostadil should be considered as an important component of therapy in severe cases of congenital diaphragmatic hernia, where deterioration of right-sided heart function occurs.