Lowest PaCO2 on the first day of life predicts mortality and morbidity among infants with congenital diaphragmatic hernia

To evaluate the association between hypercarbia in the first 24 h of life and clinical outcomes in infants with congenital diaphragmatic hernia (CDH). Retrospective review of patients entered into the CDHSG registry between 2007–2014. Half of the identified patients were analyzed to identify the PaCO2 value most predictive of mortality. Prediction models for outcomes of death, ECMO, and respiratory support at 30 days of life (DOL) were developed using PaCO2. Remaining half of data was used for validation of study findings. 1878 and 1875 patients were analyzed in the testing and validation groups. Lowest PaCO2≥60 mmHg in the first DOL is highly predictive of death prior to discharge. Prediction models including this variable demonstrate good discrimination for outcomes of death, ECMO, and respiratory support (AUC 0.8808, 0.8279, 0.8065). Lowest PaCO2 in the first DOL is an independent risk factor of mortality and morbidity in CDH.