[Severity and prognosis of congenital diaphragmatic hernia from the viewpoint of perioperative respiratory function]

We studied severity and prognosis of congenital diaphragmatic hernia (CDH) by using preductal arterial blood gas analysis (BGA) and pulmonary function tests (PFTs) in 29 newborn infants. CDH was diagnosed within 24 hours of life, and surgical repair was performed through an abdominal approach after a period of stabilization. The infants were classified into the following three groups based on the highest preoperative alveolar-arterial oxygen tension difference (A - aDO2) and the lowest arterial carbon dioxide pressure (PaCO2) values; Group A (n = 15) : A - aDO2 < 500 mmHg, PaCO2 < 40 mmHg, Group B (n = 7) : A - aDO2 > or = 500 mmHg, PaCO2 < 40 mmHg, Group C (n = 7) : A - aDO2 > or = 500 mmHg, PaCO2 > or = 40 mmHg. Furthermore, the patients were classified into the following three groups based on the preoperative respiratory system compliance (Crs) and forced vital capacity (FVC) values; Group D (n = 8) : Crs < 0.5 ml.cmH2O-1.kg-1, FVC < 10 ml.kg-1, Group E (n = 4) : Crs < 0.5 ml.cmH2O-1.kg-1, FVC > or = 10 ml.kg-1, Group F (n = 17) : Crs > or = 0.5 ml.cmH2O-1.kg-1, FVC > or = 10 ml.kg-1. The mortality in the Group C was significantly higher than in the Group A and B, and the preoperative Crs and FVC values in the Group C were significantly lower than the other groups. The mortality in the Group D and E were significantly higher than the Group F. In conclusion, it is suggested that the preoperative Crs value less than 0.5 ml.cmH2O-1.kg-1 indicates severe pulmonary hypoplasia and is critical for survival.