Impact of delayed repair and elective high-frequency oscillatory ventilation on survival of antenatally diagnosed congenital diaphragmatic hernia: first application of these strategies in the more "severe" subgroup of antenatally diagnosed newborns

Abstract

Objective: a) To analyze the influence of a new management strategy on the outcome of neonates with antenatally diagnosed congenital diaphragmatic hernia (CDH); b) to determine early prognosis respiratory factors with the new strategy.

Design: Retrospective study.

Setting: Level III perinatal center.

Patients and method: Between 1985 and 1997, 51 consecutive neonates with antenatally diagnosed CDH were admitted to our level III neonatal intensive care unit. Before 1992 (period 1; n = 19), we used conventional mechanical ventilation and early surgery requiring transfer. Since 1992 (period 2; n = 32), we prospectively tested a new approach including (a) systematically use of high-frequency oscillatory ventilation (HFOV) regardless of the initial clinical severity, (b) delayed surgery following stabilization requiring transfer to a different surgical unit, but (c) no transfer of unstable patients with surgery under HFOV in our neonatal intensive care unit (n = 10). The two cohorts were comparable in terms of potential ante and postnatal prognostic indicators.

Results: Survival was improved with the new strategy: 21/32 (66%) vs. 5/19 (26%); P < 0.02. This improvement between periods 1 and 2 was due to a decrease in both preoperative and postoperative deaths in the later period. The better survival during period 2 was associated with the appearance of very late deaths, frequent pleural effusions, and the survival of more severe forms having evolved to a chronic respiratory insufficiency. Survivors were ventilated for longer time with longer duration of oxygen supplementation. The best oxygenation index (OI), alveolar arterial difference and oscillation amplitude (P/P) during the first 24 h, but not the best PaCO2, were the most reliable prognostic indicators during period 2. An OI < or = 10 with a P/P < or = 55 cmH2O was associated with a very good prognosis (94% survival).

Conclusions: The prognosis of antenatally diagnosed CDH was improved by systematic HFOV on admission, no systematic transfer, and delayed surgery. This improvement is associated with modification of postnatal outcome.