Research Highlights
Understanding Antenatal Corticosteroids
Physicians have a better understanding of how antenatal corticosteroids should be used in the treatment of prematurity, thanks to leading-edge research by Alan Jobe, MD, PhD, in the Cincinnati Children's Division of Pulmonary Biology.
Subclinical chorioamnionitis is frequently associated with preterm deliveries before 30 weeks' gestation. Current guidelines recommend maternal glucocorticoid treatment to help the lungs to mature. Fetal exposure to proinflammation can cause acute and chronic injury – but paradoxically, the inflammation can also stimulate fetal lung maturation. Both glucocorticoids given after birth and inflammation affect lung development in the same way: by inducing the surfactant system and structural maturation, and inhibiting the development of the lung's alveoli. Cincinnati Children's researchers continue to study these mechanisms and their implications for premature infants.
Dr. Jobe and his colleagues focus on lung maturation and function, learning how lung development goes awry and how to minimize lung injury, with the goal of improving care for preterm infants. They are modeling lung inflammation and maturation in fetal animals which, when delivered preterm, are put on ventilators to test how the lung performs. Dr. Jobe's laboratory collaborates with colleagues in Australia to assess the interactions among chorioamnionitis, respiratory distress and bronchopulmonary dysplasia.
Their work is expanding the model of infection and inflammation in pregnancy, particularly how infection reaches the fetus. At the molecular level, they also are studying the effects of maturation and injury on fetal lungs.
To minimize lung injury in preemies, continuous positive airway pressure (CPAP) is being used clinically to avoid mechanical ventilation. However, little experimental information exists on its effectiveness. Dr. Jobe and his colleagues are among the first to explore the mechanisms of CPAP in preterm animals. Initial findings in the animal model show that CPAP results in lower indicators of acute lung injury than mechanical ventilation during the first two hours of life.
