Blood protein concentrations in the first two postnatal weeks associated with early postnatal blood gas derangements among infants born before the 28th week of gestation. The ELGAN Study

► Two or more days of early acidemia in preterm newborns were followed by systemic inflammation. ► Two or more days of early hypercapnia were followed by less prominent systemic inflammation. ► Two days of early hypoxemia, hyperoxemia, or hypocapnia were not followed by systemic inflammation.