The Value of the Oxygenation Index in the Prediction of Postnatal Outcome in Neonates with Congenital Diaphragmatic Hernia. Preliminary Report.

UNLABELLED The predicitive values of fetal ultrasonography and magnetic resonance imaging are well established as antenatal outcome predictors in neonates with congenital diaphragmatic hernia (CHD). Postnatal outcome predictors remain elusive. THE AIM To evaluate the value of the oxygenation index (OI) as a predictor of postnatal survival. MATERIAL AND METHODS 58 newborns with congenital diaphragmatic hernia, treated in the same centre (a university hospital) between February 2006 and March 2014 were involved in the retrospective study. Standardized preoperative stabilization involved: sedation without muscle paralysis, high frequency oscillation ventilation (HFOV) and inhaled nitric oxide (iNO, used as required). Oxygenation index OI = FiO2 x 100 x M AP/PaO2, where FiO2 is the fraction of inspired oxygen, MAP is the mean airway pressure, and PaO2 is the partial pressure of oxygen in arterial blood, calculated at the end of the first day of standardized preoperative stabilization, and evaluated as a predictor of survival. RESULTS The overall survival rate on the hospital discharge was 74.1%. As far as the oxygenation index (OI) at the end of the first day of the preoperative stabilisation is concerned, in 40/43 survivors it was below or equal to 12, in one infant it equalled 12.7, and in two remaining survivors OI was much higher (18 and 56, respectively). The prognostic value of the oxygenation index was high, with the area under the curve (AUC) 0.943, sensitivity 0.930, and specificity 0.876. CONCLUSIONS The oxygenation index (OI) calculated at the end of the first day of standardized preoperative stabilization with high frequency oscillation ventilation (HFOV) and nitric oxide (iNO) is a simple and sensitive predictor of the survival of neonates with a congenital diaphragmatic hernia. It may be a valuable tool to select high-risk neonates who might require more invasive therapeutic modalities, i.e. extracorporeal membrane oxygenation (ECMO).