The "critical" neonate with diaphragmatic hernia: a 21-year perspective.

We have seen a modest improvement in the survival of a homogeneous group of critically ill newborns with congenital diaphragmatic hernia since 1979. Twenty-seven "critical" infants have been treated who developed respiratory distress shortly after birth, required urgent resuscitation, and could not be stabilized before operation. Two died with other anomalies that appeared incompatible with prolonged survival. Ten of the 27 lived. This survival contrasts with that of only two of 17 similarly affected babies treated from 1962 to 1978. In addition, there has been no operative mortality outside of this "critical" group since 1979; whereas six noncritical babies died between 1967 to 1978. Our current therapeutic plan includes the early establishment of a respiratory alkalosis and vasodilator therapy before or during transport. Postoperatively we have attempted to maintain the baby's arterial pH greater than 7.5, Pco2 less than 25 to 30 and the PO2 approximately 150 torr. The most effective ventilatory parameters have been a rate of 130, PEEP of 5 and an inspiratory:expiratory ratio of 1:1. Peak airway pressures are kept as low as possible. Pharmacologic and ventilator therapy are weaned slowly, and intensive support has been required for at least 48 hours in each baby. Retained secretions and atelectasis of the hypoplastic lung persisted for two to several weeks postoperatively. Two babies that are one year or older still appear to have severely hypoplastic lungs on chest x-ray. M-mode echocardiography has been used to measure ventricular ejection periods. The right ventricular systolic time interval correlates with the degree of pulmonary hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)